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At least 523 records · Page 29Linked to original sources
PubMed2001

What is achieved by mammographic surveillance after breast conservation treatment for breast cancer?

BACKGROUND: After breast conservation surgery for breast cancer, patients are followed up by regular clinical examination and mammography, at intervals which vary according to local practice. However, the optimum interval remains unclear with current guidelines suggesting mammography should be carried out every 1 to 2 years. This study has investigated this aspect and, in particular, whether mammography or clinical examination or both allowed an early detection of recurrence of the disease in the conserved breast. METHODS: A total of 695 patients who had undergone breast conservation surgery were identified from a database of prospectively recorded data during the period 1990 to 1995. Clinical examination and annual mammography were performed in accordance with local protocol. The results of clinical examination, mammography, and local recurrence rates were evaluated. RESULTS: A total of 2,181 mammograms were undertaken in the 695 patients studied. Local recurrence of disease in the conserved breast occurred in 21 patients (3%), at a mean follow-up of 3.5 years. The first identification of tumor recurrence was by clinical examination in 11 patients with local recurrence, and by the surveillance mammography in the other 10 patients with local recurrence. Overall, mammography detected the local recurrence in 13 of 20 (65%) patients who underwent this examination. In the other patients, the recurrence was detected on clinical examination only. In addition, in 52 patients, mammography was falsely positive, giving a false positive rate of 2.3%. Contralateral cancers in the opposite breast were detected in 2 patients. CONCLUSIONS: The detection of local disease after breast conservation surgery requires both clinical examination and mammography. In the context of our follow-up policy, in 52% of patients with local recurrence, this was first identified by clinical examination. Disease recurrence was identified in the other 48% of patients by mammographic surveillance. Overall, mammography will identify or confirm local recurrence in two thirds of women. However, in a small number of cases (2.3% in our series) mammography will give false positive results. New imaging modalities to assist in the diagnosis of local recurrence of disease after breast conservation surgery are required.

Adult↗
PubMed2001

Clinical outcomes and fertility after conservative treatment of ovarian borderline tumors.

OBJECTIVE: To assess clinical outcome and fertility in patients treated conservatively for a low malignant potential (LMP) ovarian tumor. DESIGN: Retrospective study. SETTING: Gynecologic oncology department of a cancer care center in France. PATIENT(S): Forty-four patients treated with conservative management for a stage I (n = 32) or stage II or III (n = 12) LMP tumor. INTERVENTION(S): Thirty-three patients had unilateral adnexectomy and 11 had cystectomy. Cystectomy was bilateral in 1 patient and was done in conjunction with contralateral adnexectomy in 5 patients. MAIN OUTCOME MEASURE(S): Tumor recurrence and pregnancy rates. RESULT(S): Tumor recurrence rates after radical surgery (hysterectomy with bilateral salpingo-oophorectomy), adnexectomy, and cystectomy were 5.7%, 15.1%, and 36.3%, respectively (P<.01). Among patients who initially received conservative treatment, tumors did not recur in the form of invasive carcinoma. Five patients who had recurrence underwent repeated conservative management; these patients are alive and free of disease. Seventeen pregnancies (of which 15 were spontaneous) occurred in 14 patients; 13 pregnancies occurred in patients with stage I disease and 4 occurred in patients with stage III disease. CONCLUSION(S): Conservative management of LMP tumor significantly increases the risk of recurrence but does not affect overall survival. Such management offers even patients with advanced disease the chance to have spontaneous pregnancy. Conservative management might be proposed in young patients who wish to preserve their fertility, but careful follow-up will be required to detect tumor recurrence.

Adolescent↗
PubMed1998

Conservative surgical management of bilateral Wilms tumor: results of the United Kingdom Children's Cancer Study Group.

PURPOSE: Bilateral Wilms tumor presents the clinician with a treatment dilemma. Since 1980 most centers of the United Kingdom Children's Cancer Study Group have used a conservative surgical approach with initial biopsy followed by chemotherapy and delayed surgical resection. We assess the outcome of this treatment approach in terms of survival, and preservation of renal mass and function. MATERIALS AND METHODS: We retrospectively analyzed the records of 71 children with bilateral Wilms tumor diagnosed between 1980 to 1995 at 17 United Kingdom Children's Cancer Study Group centers. In 57 patients conservative surgical treatment with initial biopsy was followed by chemotherapy and delayed tumor resection, while 13 underwent initial surgical resection followed by chemotherapy. One patient was excluded from study because the lesion in 1 kidney proved to be a benign cyst. Mean followup was 6 years (range 1 to 15). The percentage of renal tissue involved with tumor and preserved was estimated, and renal function at the last followup was recorded. RESULTS: Overall survival was 69% with similar survival in the conservatively treated and initial surgical resection groups. At the last followup renal function was normal in 80% of the patients in each group. Mean preserved renal mass was 45 and 35% in the conservatively treated and initial resection groups, respectively, with a trend toward better preservation in those treated conservatively. Bilateral Wilms tumor with an unfavorable histology was associated with a poor prognosis. CONCLUSIONS: Conservative surgical treatment of favorable histology bilateral Wilms tumor may improve the preservation of renal mass and function without impairing patient survival.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Conservative elective treatment of upper urinary tract tumors: a multivariate analysis of prognostic factors for recurrence and progression.

PURPOSE: We evaluate the safety and efficacy of conservative elective treatment of upper urinary tract tumors, and determine predictive factors for recurrence and progression to optimize indications of this type of treatment. MATERIALS AND METHODS: Since 1984 we have performed a prospective study of conservative treatment of single, low grade and stage, less than 3 cm. upper tract tumors. The study includes 54 patients with a normal contralateral kidney who had been followed for more than 36 months. Open conservative surgery was performed in 31 cases and endourological surgery in 23. Minimum followup was 36 months, maximum 210 and mean 84.8. Univariate and multivariate analyses of recurrence and progression were performed in relation to age, sex, association with a bladder tumor, bladder tumor stage and grade, sequence of bladder tumor in relation to upper urinary tract tumor, number of previous bladder tumor recurrences, association with bladder carcinoma in situ, upper urinary tract tumor grade, stage, location, size and therapy, and upper urinary tract cytology. RESULTS: Of the 54 patients 19 (35%) had recurrence, which was bilateral recurrence in 4, and progression occurred in 9 (16%). At the end of analysis 44 (62.9%) patients were disease-free and alive at a mean time of 92.88 months, 13 (24%) died disease-free at a mean of 72.7 months and 7 (12.9%) died of disease at a mean of 97.85 months. Cause specific mortality occurred in 7 (12.9% cases). Among the 54 initially conservatively treated units 42 (77.7%) kidneys were ultimately preserved. On univariate and multivariate analysis tumor location in the renal pelvis and association with a previous multi-recurrent bladder tumor were variables significantly related to recurrence and progression, as well as bilateral recurrence. CONCLUSIONS: Conservative treatment is an optional approach for select upper urinary tract tumors. The strongest risk factors for recurrence and progression were association with a previous multi-recurrent bladder tumor and tumor location in the renal pelvis but these conditions were also the strongest risk factors for bilateral recurrence. Conservative treatment can also be recommended in these cases but only with compliant patients and close followup.

Adult↗
PubMed2002

Transurethral prostate resection, noncontact laser therapy or conservative management in men with symptoms of benign prostatic enlargement? An economic evaluation.

PURPOSE: We evaluated the cost-effectiveness of noncontact laser therapy compared with transurethral prostate resection and conservative treatment in men with symptoms associated with benign prostatic enlargement. MATERIALS AND METHODS: A total of 340 men with uncomplicated lower urinary tract symptoms participated in a large multicenter pragmatic randomized trial called the CLasP (Conservative management, Laser therapy, transurethral resection of the Prostate) study. Costs to the United Kingdom National Health Service and patients were determined from the time of randomization to the 7.5-month followup. Incremental cost-effectiveness ratios using conservative management as the base case were calculated for certain trial outcomes, including International Prostate Symptom Score (I-PSS), I-PSS quality of life score, maximum urinary flow, post-void residual urine volume, quality adjusted life-years and a composite measure of success based on I-PSS and maximum urinary flow. One-way sensitivity analysis of the basic costs and incremental cost-effectiveness ratios were done from the NHS viewpoint. RESULTS: Mean costs per patient were greatest for noncontact laser therapy and least for conservative management. The incremental cost-effectiveness ratios showed that transurethral prostate resection was more cost-effective than noncontact laser treatment for all primary trial outcomes. The incremental cost-effectiveness ratios of transurethral prostate resection compared with conservative management were pound 81 per unit decrease in the I-PSS score and pound 1,338 per additional successful case per 100 patients. Sensitivity analysis showed that the initial results were robust. CONCLUSIONS: Noncontact laser was the mostly costly treatment option. Transurethral prostate resection was more cost-effective than noncontact laser therapy in terms of symptomatic improvement. In men wishing to delay treatment conservative treatment appears to provide a cost-effective alternative in the short term.

Adult↗
PubMed2002

Conservation of the segmented germband stage: robustness or pleiotropy?

Gene expression patterns of the segment polarity genes in the extended and segmented germband stage are remarkably conserved among insects. To explain the conservation of these stages, two hypotheses have been proposed. One hypothesis states that the conservation reflects a high interactivity between modules, so that mutations would have several pleiotropic effects in other parts of the body, resulting in stabilizing selection against mutational variation. The other hypothesis states that the conservation is caused by robustness of the segment polarity network against mutational changes. When evaluating the empirical evidence for these hypotheses, we found strong support for pleiotropy and little evidence supporting robustness of the segment polarity network. This points to a key role for stabilizing selection in the conservation of these stages. Finally, we discuss the implications for robustness of organizers and long-term conservation in general.

Animals↗
PubMed1998

Myocardial infarction among women with early-stage breast cancer treated with conservative surgery and breast irradiation.

PURPOSE: To assess the possible impact of the irradiation on the risk of acute myocardial infarction among breast cancer patients treated with conservative surgery and postoperative radiation therapy. METHODS AND MATERIALS: The incidence of and mortality from acute myocardial infarction was assessed in a group of 684 women with early-stage breast cancer diagnosed during 1976-1987 who had been treated with breast conserving surgery plus postoperative radiation therapy given with tangential photon fields. In 94% of the patients the total dose was between 48-52 Gy given with 2 Gy daily fractions 5 days per week for a total treatment period of about 4 1/2-5 1/2 weeks. In 88% of the patients the target volume included the breast parenchyma alone. In the remaining patients regional nodal areas were also irradiated. A concurrent group of 4,996 breast cancer patients treated with mastectomy without postoperative radiation therapy was used as a reference. RESULTS: After a median follow-up of 9 years (range: 5-16 years) 12 conservatively treated patients (1.8%) had developed an acute myocardial infarction and 5 (0.7%) had died due to this disease. The age-adjusted relative hazard of acute myocardial infarction for the conservative group vs. the mastectomy group was 0.6 (95% C.I.: 0.4-1.2) and for death due to this disease 0.4 (0.2-1.1). The incidence of acute myocardial infarction among the conservatively treated women was similar irrespective of tumor laterality. CONCLUSIONS: There was no indication of an increased risk of acute myocardial infarction with the radiation therapy among the women treated with conservative surgery. However, due to the small number of events the study could not exclude the possibility that cardiac problems may arise in some patients with left-sided cancers who have their heart located anteriorly in the mediastinum. Individual, three-dimensional dose planning represents one method to identify such patients and is basic to technical changes aimed at decreasing the cardiac radiation dose volume.

Adult↗
PubMed2003

Size of invasive breast cancer and risk of local recurrence after breast-conservation therapy.

Risk of local recurrence is one important factor that determines a woman's suitability for breast-conservation therapy. With the evolution of oncoplastic surgery, tumours of a size that traditionally require mastectomy may be treated by breast conservation and partial breast reconstruction. This article reviews the evidence relating to tumour size as a risk factor for local recurrence to assess whether this change in practice is appropriate. A literature review through Medline and Pubmed was performed. All pathological studies analysing tumour size as a predictor of multifocality and all randomised trials and large case series of breast conservation including tumours larger than 2 cm were reviewed and critically interpreted. Pathological studies report consistent evidence that tumour size is not predictive of multifocality. Randomised trials and clinical series of breast conservation report conflicting evidence relating to tumour size as a risk factor for local recurrence, although most studies report no association. Evidence relating to cancers over 3 cm is limited. There is little evidence to justify the use of tumour size alone as an exclusion criterion for breast-conservation therapy. A registration study of patients with cancers larger than 3 cm treated by breast conservation with or without partial breast reconstruction is proposed.

Breast Neoplasms↗
PubMed1996

Conservation within the myosin motor domain: implications for structure and function.

BACKGROUND: Myosins are motors that use energy supplied by ATP to travel along actin filaments. The structure of myosin is known, but the actin-binding site is not well defined, and the mechanisms by which actin activates ATP hydrolysis by myosin, and myosin moves relative to the actin filament, developing force, are not fully understood. Previous phylogenetic analyses of the motor domain of myosins have identified up to twelve classes. We set out to analyse the positions of conserved residues within this domain in detail, and relate the conserved residues to the myosin structure. RESULTS: Our analysis indicates that there are at least thirteen myosin classes. Conserved residues in the motor domain have been positioned within the framework provided by the recent crystal structures, thus helping to define those residues involved in actin and ATP binding, in hydrolysis and in conformational change. This has revealed remarkably poor overall conservation at the site thought to be involved in actin binding, but several highly conserved residues have been identified that may be functionally important. CONCLUSIONS: Information from such a sequence analysis is a useful tool in the further interpretation of X-ray structures. It allows the position of crucial residues from other members of a superfamily to be determined within the framework provided by the known structures and the functional significance of conserved or mutated residues to be assessed.

Actins↗
PubMed1991

Deduced amino acid sequence of Escherichia coli adenosine deaminase reveals evolutionarily conserved amino acid residues: implications for catalytic function.

The goal of the research reported here is to identify evolutionarily conserved amino acid residues associated with enzymatic deamination of adenosine. To do this, we isolated molecular clones of the Escherichia coli adenosine deaminase gene by functional complementation of adenosine deaminase deficient bacteria and deduced the amino acid sequence of the enzyme from the nucleotide sequence of the gene. Nucleotide sequence analysis revealed the presence of a 996-nucleotide open reading frame encoding a protein of 332 amino acids having a molecular weight of 36,345. The deduced amino acid sequence of the E. coli enzyme has approximately 33% identity with those of the mammalian adenosine deaminases. With conservative amino acid substitutions the overall sequence homology approaches 50%, suggesting that the structures and functions of the mammalian and bacterial enzymes are similar. Additional amino acid sequence analysis revealed specific residues that are conserved among all three adenosine deaminases and four AMP deaminases for which sequence information is currently available. In view of previously published enzymological data and the conserved amino acid residues identified in this study, we propose a model to account for the enzyme-catalyzed hydrolytic deamination of adenosine. Potential catalytic roles are assigned to the conserved His 214, Cys 262, Asp 295, and Asp 296 residues of mammalian adenosine deaminases and the corresponding conserved amino acid residues in bacterial adenosine deaminase and the eukaryotic AMP deaminases.

Adenosine Deaminase↗
PubMed2004

[Conservative therapy adapted to findings of superficial chronic venous ulcers].

A successful treatment of venous ulcers represents a special clinical challenge. The following conservative wound management of a high-risk patient presents an alternative to primary surgical treatment. A patient of 79 years in reduced general state with multiple underlying concomitant diseases is hospitalized with superinfected, necrotic and painful ulcers. Due to the severe morbidity of the patient the regular therapy of the underlying venous insufficiency consisting of stripping of great saphenous vein and ligation of perforator veins, is contraindicated. After interdisciplinary discussion conservative therapy is carried on. The conservative therapy includes initial local debridement, moist wound-healing dressings, compression therapy, systemic antibiotic and analgesic therapy, completed by stabilization of patient's general state. In regular intervals a photographic documentation of the wound is carried out. The period of treatment and observation is 63 days. Due to conservative wound management a clear improvement of the wound condition and of the patient's general state is observed. The period needed for change of wound dressing can be reduced from 2 hours to 30 minutes. The painscore is reduced from 8/10 to 4/10 as well as the analgesic need. The photographic documentation shows a clear progress of healing within 9 weeks. Under antibiotic therapy and conservative wound management the increased inflammation parameters are declining. By choosing a conservative therapeutical regime adapted to clinical findings superinfected, chronic venous ulcers are turned into a stable condition.

Aged↗
PubMed1996

Liquid conservation in orangutans (Pongo pygmaeus) and humans (Homo sapiens): individual differences and perceptual strategies.

Four orangutans (1 juvenile, 2 subadults, and 1 adult) and ten 6-8-year-old children were tested in 4 liquid conservation tasks of increasing levels of difficulty. Task difficulty depended on the type of transformation (continuous vs. discontinuous quantities) and the relative contrast between the shapes of the containers. Results indicate that orangutans did not display conservation in the strict sense; instead they showed "partial" conservation (intermediate reactions according to J. Piaget & B. Inhelder, 1941). In contrast, some of the children provided evidence of conservation in all 4 tasks, showing "true" or logically necessary conservation in the original sense proposed by J. Piaget and B. Inhelder (1941). Although orangutans did not show conservation in the strict sense, as J. Piaget (1955) and others have generally agreed it should be defined, orangutans behaved as individual and creative problem solvers, adopting different perceptual strategies depending on the task.

Aging↗
PubMed1994

Changes in use of breast-conserving therapy in years 1978-2000.

The treatment of breast cancer patients has changed rapidly in the past decade, but empirical data at local and national level are scarce. Predicting the consequences of screening for primary treatment is consequently difficult. The aim of this analysis of records on admissions to hospital of women with breast cancer and/or for breast surgery (1975-90) together with a survey of all Dutch radiotherapy departments (1986-88) is to show the change in breast-conserving therapy and other primary treatment before the start of breast cancer screening in The Netherlands. There was a modest increase in breast-conserving therapy after 1981, coinciding with the first publication on its trial, followed by a sharp increase between 1985 and 1990, after the second publication. At the end of that 5 year period, 36% of all women with newly diagnosed invasive breast cancer underwent this type of surgery. Breast-conserving surgery is always followed by radiotherapy, but there has been a clear reduction in post-operative radiation after mastectomy. The percentage of breast-conserving therapy is at present higher in The Netherlands than in the USA. Implementing the Dutch screening programme will result in a maximum increase in breast-conserving therapy at national level of 34%, which stabilises at +21%, or a 50% maximum increase at local level. The number of women treated by mastectomy will ultimately decrease by 9%. Given the rapidity of change towards the use of breast-conserving surgery, which is enhanced by screening, recent information will be needed in predicting capacity and assessing whether screen-detected women are treated adequately.

Breast Neoplasms↗
PubMed1979

Mechanism of renal potassium conservation in the rat.

The mechanisms responsible for renal potassium (K) conservation during dietary potassium deficiency are poorly understood. This study was undertaken to investigate the time course of potassium conservation as well as the roles of distal sodium (Na) delivery, the distal delivery or sodium plus a nonpermeable anion, mineralocorticoid hormone, renal tissue potassium content, and Na-K-ATPase activity in renal potassium conservation. After 72 hours of a low-potassium diet, basal potassium excretion was negligible. After 24 hours, and even more so after 72 hours of potassium restriction, the kaliuretic response to increasing distal delivery of sodium or sodium plus a nonpermeable anion was impaired. After 24 hours of a low-potassium diet, plasma aldosterone levels fell from 180 +/- 25 to 32 +/- 9 pg/ml (P less than 0.001). Mineralocorticoid hormone given in the first 24 hours of a low-potassium diet resulted in a greater potassium loss (1564 +/- 125 muEq) than it did in controls on the same diet not receiving mineralocorticoid hormone (1032 +/- 83 muEq, P less than 0.005). In contrast, after 72 hours of diet, large doses of mineralocorticoid hormone failed to cause a kaliuresis in either anesthetized or conscious rats. After both 24 and 72 hours, outer medullary Na-K-ATPase was increased. At 72 hours, cortical, medullary, and papillary tissue potassium concentrations were significantly depressed. Acute administration of potassium repleted tissue potassium levels and restored basal and saline-stimulated potassium excretion to normal. Although potassium excretion was markedly depressed after 24 hours of the low-potassium diet, 42K microinjection studies of the distal nephron did not suggest any increase in potassium reabsorption. Following 72 hours of diet, potassium reabsorption increased significantly from 26 +/- 2% to 41 +/- 2% (P less than 0.001). We conclude that renal potassium conservation is at first primarily related to a decrease in potassium secretion, which is most likely mediated by falling levels of mineralocorticoid hormone. After 72 hours of the potassium-deficient diet, however, potassium conservation becomes independent of mineralocorticoid hormone, distal delivery of sodium, and Na-K-ATPase. The decreased tissue potassium content appears to be the primary mediator of both the increase in potassium reabsorption by the distal nephron and of renal potassium conservation at this time.

Aldosterone↗
PubMed1992

Structural analysis of the regulatory elements of the type-II procollagen gene. Conservation of promoter and first intron sequences between human and mouse.

Transcription of the type-II procollagen gene (COL2A1) is very specifically restricted to a limited number of tissues, particularly cartilages. In order to identify transcription-control motifs we have sequenced the promoter region and the first intron of the human and mouse COL2A1 genes. With the assumption that these motifs should be well conserved during evolution, we have searched for potential elements important for the tissue-specific transcription of the COL2A1 gene by aligning the two sequences with each other and with the available rat type-II procollagen sequence for the promoter. With this approach we could identify specific evolutionarily well-conserved motifs in the promoter area. On the other hand, several suggested regulatory elements in the promoter region did not show evolutionary conservation. In the middle of the first intron we found a cluster of well-conserved transcription-control elements and we conclude that these conserved motifs most probably possess a significant function in the control of the tissue-specific transcription of the COL2A1 gene. We also describe locations of additional, highly conserved nucleotide stretches, which are good candidate regions in the search for binding sites of yet-uncharacterized cartilage-specific transcription regulators of the COL2A1 gene.

Amino Acid Sequence↗
PubMed1979

Verbal training to improve explanations of conservation with aphasic adults.

Recent research has indicated a need to study the relationship between the language of the adult aphasic and his attempts at cognitive processing. Nine aphasic adults who demonstrated a minimal ability to explain conservation (as defined by Piaget), a cognitive task which they understood, were given verbal model training to improve their explanations of weight and liquid conservation. Each subject was given a pretest, an experimental condition during which explanations for weight conservation only were trained, a control condition during which subjects named pictured common objects, and a posttest. Order of presentation of the experimental and control conditions was varied. As a result of training, a greater number of explanations (quantitative improvement) and a greater number of explanatory concepts (qualitative improvement) were expressed for both the trained and nontrained conservation tasks. It is suggested that the improvement in conservation explanations is the result of "response facilitation effects" as described by Bandura. Furthermore, the improvement in conservation explanations is supportive of Schuell's concept of impaired linguistic retrieval mechanisms in aphasia.

Adult↗
PubMed2000

The use of a blood conservation pressure transducer system in critically ill patients.

We tried to determine if a blood conservation pressure transducer system reduced blood transfusions, increased haemoglobin concentration or reduced line infections in critically ill patients. One hundred patients were randomly allocated to conventional or blood conserving systems attached to systemic and pulmonary arterial catheters. Intravascular lines were cultured after removal. There were no significant differences in transfusions or haemoglobin concentration. Blood conservation: median units transfused, 2 (range 0-19); mean haemoglobin at 7 days, 11.2 g.dl-1 (SD, 1.0). Conventional: median units, 2 (range 0-34); mean haemoglobin at 7 days, 11.1 g.dl-1 (SD 1.0). Thirty-seven of 99 arterial lines were colonised in the controls compared with 29 of 96 in the blood conservation group. Patients who required haemofiltration in both groups had significantly increased transfusion requirements. Haemofiltration: median 6 units (range 0-34) vs. non-haemofiltered: median 1 (range 0-14; p < 0.001). There were no significant differences in transfusions, haemoglobin concentration or line colonisation with the blood conservation system. There is considerable potential for blood conservation during haemofiltration.

Adult↗
PubMed2003

Conservation ethics and anaesthesia.

The current attitude of conservators towards restoration is to preserve objects and materials in the condition as they are but without attempting to restore them 'as new'. Museum objects have generally ceased to serve their original utilitarian function but have become objects for study, information and inspiration. Conservation and restoration are discussed in relation to anaesthetic exhibits. Conservation is the prevention, detection, containment, control and recovery but risk avoidance and monitoring hopefully will lessen the need for conservation. Some objects such as rubber and plastic items are, by their very nature, prone to ageing, accident and mistreatment. Cleaning and maintenance may lead to loss of original detail and is 'an act of critical interpretation'. Reshaping of distorted objects and repair of broken pieces can sometimes be justified but, in other work, the actual restoration may become part of the object's history that should not be lost in trying to restore something to a presumed earlier state. The mind interprets images by reference to earlier patterns and so imperfections, if not disguised, may be unduly distracting. Museums exist for information, evidence, enlightenment and even entertainment. Conservation must serve these purposes and is not an end in its own right. The professional actions of the conservator must be governed by a total respect for physical, historic, and aesthetic integrity but this must be interpreted widely.

Anesthesiology↗