Lyapunov partition functions for the dimensions of chaotic sets.
Explore the source record for details and available documents.
Journal Article↗
Biomedical subjects
T Sauer
Publications and source records attributed to T Sauer.
Cutaneous 10 MHz ultrasound B scan allows the quantitative assessment of burn depth.
Alterations in the epidermis and dermis after a scald burn (deep dermal wound) are sonographically displayed by different echo reflections. Histological slide preparations from various layers of healthy skin were studied to check the ultrasound analysis. Echo reflections of high and low density showed a close correlation to real anatomical structures in the histological slides. The 10-MHz B scan allows the differentiation of 0.1 mm. Heat causes an increase in dermal thickness of between 50 and 100 per cent for the period between 1 and 6 h after injury. Identifying the layers corresponding to the histological slides makes it is possible to measure the distance between the interfaces. This improves the quantitative assessment of both the depth and the area of thermal injury.
Animals↗
[Effect of etofenamate on early scald-induced edema. An experimental ultrasound study].
Explore the source record for details and available documents.
Animals↗
The recurrence rate of adenomas following polypectomy and complete colonoscopy.
Explore the source record for details and available documents.
Adult↗
Mucinous adenocarcinoma of the appendix presenting as an ovarian cystadenocarcinoma: case report and review of appendiceal neoplasms with ovarian metastases.
Primary adenocarcinoma of the vermiform appendix is a rare clinical entity that is virtually never diagnosed preoperatively. A case of mucin-producing adenocarcinoma of the appendix manifesting as a pelvic mass is presented. The ultrasonographic finding of a multilocular cystic lesion with thick septa and solid components was consistent with an ovarian cystadenocarcinoma. A review of primary appendiceal neoplasms with ovarian metastases is given.
Adenocarcinoma, Mucinous↗
[Neoplastic colonic polyps. Occurrence, therapeutic principles and control routines].
Explore the source record for details and available documents.
Age Factors↗
[Cytological endometrial diagnosis with Endoscan].
Explore the source record for details and available documents.
Adult↗
Radiotherapy of T4 bladder carcinoma.
A 16% 5-year crude survival was observed in 159 irradiated patients with T4NXMO bladder carcinoma. The presence of a T4a tumour and a good performance status were important prognostic parameters. The combination of radiotherapy and weekly injections of 5-FUra (12 mg/kg) resulted in a significant 2-year survival increase. New regimens of combined radiotherapy/chemotherapy should be developed for patients with T4NXMO bladder carcinoma. The palliation effect of radiotherapy should further be evaluated, preferably in prospective studies comparing radiotherapy with other types of palliation treatment.
Aged↗
Late changes following single dose roentgen irradiation of rat small intestine.
In female Wistar rats a 10 cm long exteriorized mid small intestinal segment was roentgen irradiated with 17, 19, 21 and 23 Gy as single exposures. Animals were killed in groups of 3 at intervals of 6 weeks from 2 to 50 weeks following irradiation. Irradiation injury was assessed using 8 macroscopic and histopathologic parameters, and an injury score for each animal was calculated. The parameters used were divided in 2 subgroups, early and late alterations, showing different types of development. The score for the early alterations decreased from 2 to 20 weeks following irradiation and then remained constant. The late alterations increased and seemed to stabilize about 8 weeks following irradiation. After the initial 20 weeks there was no progression of irradiation injury.
Animals↗
Effects of dose fractionation on late roentgen radiation damage of rat small intestine.
In female Wistar rats a 10 cm long exteriorized mid small intestinal segment was roentgen irradiated. Nominal standard radiation doses were 17 and 19 Gy, given as a single exposure and in 2 and 3 fractions with intervals of 48 hours. Animals were killed and examined in groups of 3 every 6 weeks from 8 to 44 weeks following irradiation. Macroscopic and histopathologic parameters of irradiation injury were used to calculate an injury score for each animal. In the 2 fractions group both mortality and irradiation injury score were higher than in the single exposure and 3 fractions groups. The difference was due in particular to persisting mucosal ulcerations and epithelial atypia. Adenocarcinoma of the irradiated intestine was found in 4 animals.
Adenocarcinoma↗
Morphology of the epididymis of the cock (Gallus domesticus) and its effect upon the steroid sex hormone synthesis. I. Ontogenesis, morphology and distribution of the epididymis.
The epididymis of the cock is divided into a main part and an appendix epididymidis. The main part of the epididymis is firmly connected to the testis. The sperm transporting tubes open into the ductus epididymidis along its entire length. The rete testis, as the most proximal part of the epididymis, develops from mesenchym cells. The rete testis connects the tubuli seminiferi with the ductuli efferentes proximales which develop from the Bowman's capsules of the mesonephros. The ductuli efferentes distales develop from the proximal tubules, conducting segments (loops of Henle), and the distal tubules of the mesonephros. The short ductuli conjugentes which open into the ductus epididymidis, originate from the connecting segments of the mesonephros. In the sexually mature cock the rete testis, the ductuli efferentes proximales, and the ductus epididymidis all show an enlargement in the lumen. In the ductuli efferentes proximales and in the ductus epididymidis one can observe a formation of globuli and cell protrusion which lead to a loss of the surface structure of the epithelial cells. The appendix epididymidis and the capsula fibrosa of the adrenal gland are joined by connective tissue. The appendix epididymidis consists of the blindly ending ductus aberrans (the crainal continuation of the ductus epididymidis) and the ductuli aberrantes which open into the ductus aberrans. The blind ends of the ductuli aberrantes end in the capsula fibrosa of the adrenal gland.
Animals↗
Morphology of the epididymis of the cock (Gallus domesticus) and its effect upon the steroid sex hormone synthesis. II. Steroid sex hormone synthesis in the tubuli epididymidis and the transformation of the ductuli aberrantes into hormone producing noduli epididymidis in the capsule of the adrenal gland of the capon.
Distinct histochemical and ultrastructural signs of a steroid hormone synthesis are found in the sexually mature cock, particularly in the ductuli efferentes proximales of the main part of the epididymis and in the blind ends of the ductuli aberrantes of the appendix epididymidis. These signs are more distinct in the appendix epididymidis of the capon since the blind ends of the ductuli aberrantes transform into steroid sex hormone producing noduli epididymidis after they sprout out intensively and branch inside or beneath the adrenal capsule. The signs of virility were lost immediately after castration. They become more distinct again due to the hormonal activity of the noduli. Due to the morphologic agreement the noduli epididymidis of the capon are homologous to the noduli epoophori of the hen.
Androgens↗
Discriminating deterministic versus stochastic dynamics in neuronal activity.
An approach to discriminating deterministic versus stochastic dynamics from neuronal data is presented. Direct tests for determinism are emphasized, as well as using time series with clear physical correlates measured from small ensembles of neurons. Surrogate data are used to provide null hypotheses that the dynamics in our data could be accounted for by linear stochastic systems. Algorithms are given in full, and the analysis of an experimental example is given.
Algorithms↗
ASCUS and AGUS criteria. International Academy of Cytology Task Force summary. Diagnostic Cytology Towards the 21st Century: An International Expert Conference and Tutorial.
ISSUES: The conference participants addressed the following issues: (1) reporting of equivocal diagnoses, (2) strategies to minimize the use of such diagnoses, (3) morphologic criteria, and (4) management of women with equivocal diagnoses. CONSENSUS POSITION: Equivocal diagnoses should be minimized, to the extent possible, by emphasizing cytologist education and training, improved specimen collection and quality assurance monitoring of individual and laboratory diagnosis rates. Cases fulfilling criteria for other diagnostic entities should not be included in the equivocal category. Regardless of the term utilized, an equivocal diagnosis should be qualified in some manner to indicate that the diagnosis defines a patient at increased risk of a lesion, particularly for those cases which raise concern about a possible high grade lesion. Qualification of an equivocal diagnosis can also be accomplished by appending laboratory statistics of the likelihood of various clinical outcomes or recommendations for patient follow-up. In contrast to favoring a reactive process versus squamous intraepithelial lesion (SIL), a more rationale approach to qualification of atypical squamous cells of undetermined significance may be to separate cases equivocal for low grade SIL from those suspicious for high grade SIL. With regard to glandular lesions, the conference participants expressed unanimous support for the separation of adenocarcinoma in situ (AIS) from atypical endocervical cells of undetermined significance when sufficient criteria are present. However, the diagnosis of a precursor lesion to AIS, endocervical glandular dysplasia, was controversial. The majority of conference participants discourage the use of such terms as mild glandular dysplasia and low grade glandular dysplasia for cytologic diagnoses. ONGOING ISSUES: Conference participants agreed that a term reflecting diagnostic uncertainty is necessary to communicate findings that are equivocal. However, participants could not agree on the wording of such a term. Opinions differed as to: (1) use of atypical, abnormal or morphologic changes to describe cell changes, (2) whether the diagnosis should indicate a squamous or glandular origin of the cells in question when this determination can be made, and (3) the value of defining morphologic criteria for such a diagnosis. The debate over terminology, as well as morphologic criteria, is ongoing, and the readership is invited to communicate opinions to Acta Cytologica. Management of women with equivocal diagnoses varies widely from locale to locale and may differ based on how the equivocal diagnosis is qualified. Findings insufficient for the diagnosis of a high grade lesion may warrant more aggressive follow-up than cases equivocal for a low grade lesion. Where sensitivity of detection of lesions is of paramount importance, follow-up will generally consist of more frequent cytology screening or colposcopy and biopsy. However, in some countries it is considered unethical to have a high percentage of false positive diagnoses, which result in overtreatment and an unnecessary burden for women participating in cervical screening. Future studies may provide a morphologic, or perhaps molecular, basis for distinguishing true precursors of neoplasia from minor lesions of no significant clinical import; this would allow a more coherent and rational approach to diagnosis and management of women with equivocal cytologic findings.
Adenocarcinoma↗
Cell preparation methods and criteria for sample adequacy. International Academy of Cytology Task Force summary. Diagnostic Cytology Towards the 21st Century: An International Expert Conference and Tutorial.
ISSUES: Cell Preparation Methods Standardized fixation and optimal staining Sampling of cervix, sampling error, homogenization of sample, subsampling Assessment of liquid-based preparations: efficacy and economic impact Training and transitional procedures before full implementation of new technologies Criteria for Sample Adequacy Clinician responsibility for collecting and providing representative sample to laboratory Collection instruments, number of slides Cellular content of samples: evidence of transformation zone (TZ) sampling, number of squamous cells present, obscuring factors Screening issues CONSENSUS POSITION The conventional cervical smear remains the standard method of cervical cancer screening but has limitations in individual test sensitivity and specificity. Sample takers should: (1) receive appropriate training in sample collection, (2) be held responsible for providing the laboratory with appropriate samples, and (3) have their performance monitored. The instruments used for sampling should collect cells from both the ectocervix and endocervix; optimally, TZ sampling, represented by the presence of endocervical or squamous metaplastic cells, should be identifiable in samples other than atrophic specimens. The adequacy of a specimen (as judged microscopically) does not guarantee that it is representative of the cervix. Each cytology report should include a comment on cellular content/adequacy of the specimen. Liquid-based preparations may overcome many of the inherent problems with the conventional cervical smear. ONGOING ISSUES: We need further data on the cost-effectiveness of making two slides from cervical specimens and/or using two samplers rather than a single one. Do we have enough information to make recommendations as to the appropriate type of sampler to be used in particular situations, such as routine screening? What is the best method of screening for/detecting endocervical glandular neoplasia? How are such terms as unsatisfactory and inadequate defined in cervical cytology classifications other than the Bethesda System? What number and types of epithelial cells should be present (visualized) in a cervical smear or liquid-based preparation for it to be considered adequate? Do we need to have evidence of TZ sampling in specimens taken during the follow-up period after treatment of squamous intraepithelial lesion or after detection of endocervical glandular neoplasia? What criteria for obscuring factors, such as blood and inflammation, should be used in assessing adequacy? Cost-benefit analyses of utilizing liquid-based preparations are needed. Should we inform women about the technical details of the test methods available or chosen by the laboratory? Are women in a position to decide which method is the most appropriate to assess their cervical scrape sample? We need to obtain more information about the properties of proprietary liquid fixative/transport media with respect to inactivation of viral pathogens, tuberculosis and other bacterial pathogens and suitability for immunobiologic and molecular tests, etc. We need to obtain more information on the use of stoichiometric stains and the limitations of Papanicolaou stain for image analysis systems. The use of liquid-based preparations for nongynecologic cytopathology and ancillary tests must be considered, including criteria for adequacy. We need to obtain more information on the time required for and best methods of training experienced cytotechnologists to become competent at assessing liquid-based cervical preparations.
Cell Biology↗
Computerized screening devices and performance assessment: development of a policy towards automation. International Academy of Cytology Task Force summary. Diagnostic Cytology Towards the 21st Century: An International Expert Conference and Tutorial.
ISSUES: The extension of automation to the diagnostic assessment of clinical materials raises issues of professional responsibility, on the part of both the medical professional and designer of the device. The International Academy of Cytology (IAC) and other professional cytology societies should develop a policy towards automation in the diagnostic assessment of clinical cytologic materials. CONSENSUS POSITION: The following summarizes the discussion of the initial position statement at the International Expert Conference on Diagnostic Cytology Towards the 21st Century, Hawaii, June 1997. 1. The professional in charge of a clinical cytopathology laboratory continues to bear the ultimate medical responsibility for diagnostic decisions made at the facility, whether automated devices are involved or not. 2. The introduction of automated procedures into clinical cytology should under no circumstances lead to a lowering of standards of performance. A prime objective of any guidelines should be to ensure that an automated procedure, in principle, does not expose any patient to new risks, nor should it increase already-existing, inherent risks. 3. Automated devices should provide capabilities for the medical professional to conduct periodic tests of the appropriate performance of the device. 4. Supervisory personnel should continue visual quality control screening of a certain percentage of slides dismissed at primary screening as within normal limits (WNL), even when automated procedures are employed in the laboratory. 5. Specifications for the design of primary screening devices for the detection of cervical cancer issued by the IAC in 1984 were reaffirmed. 6. The setting of numeric performance criteria is the proper charge of regulatory agencies, which also have the power of enforcement. 7. Human expert verification of results represents the "gold standard" at this time. Performance characteristics of computerized cytology devices should be determined by adherence to defined and well-considered protocols. Manufacturers should not claim a new standard of care; this is the responsibility of the medical community and professional groups. 8. Cytology professionals should support the development of procedures that bring about an improvement in diagnostic decision making. Advances in technology should be adopted if they can help solve problems in clinical cytology. The introduction of automated procedures into diagnostic decision making should take place strictly under the supervision and with the active participation and critical evaluation by the professional cytology community. ONGOING ISSUES: Guidelines should be developed for the communication of technical information about the performance of automated screening devices by the IAC to governmental agencies and national societies. Also, guidelines are necessary for the official communication of IAC concerns to industry, medicolegal entities and the media. Procedures and guidelines for the evaluation of studies pertaining to the performance of automated devices, performance metrics and definitions for evaluation criteria should be established.
Automation↗
Quality assurance/control issues. International Academy of Cytology Task Force summary. Diagnostic Cytology Towards the 21st Century: An International Expert Conference and Tutorial.
ISSUES: General definitions of quality assurance and quality control (QA/C) have existed in many forms for decades, and a new discipline guides their application to diverse industrial and recently medical processes without much fanfare. However, in the field of cervical cytology screening, the range of QA/C options has recently broadened and become controversial. With the advent of new systems of terminology, larger-scale laboratories and new technologies--plus strong governmental and legal pressures in some nations--the range of extremely difficult and sometimes expensive QA/C choices our community faces is greater than ever. CONSENSUS POSITION: At our conference, the basic definitions of QA/C posed little difficulty. Presentation of the range of methods in use today and of those based on new technologies where use is proposed or has just begun also was achieved with little or no dispute. However, there was lack of consensus on exactly how QA/C methods are to be assessed. Indeed, there was little consistency in the use of different outcome measures with which we can judge success or failure of specific QA/C options. In addition, the tension between pressure to adopt sometimes uncertain or expensive method enhancements and pressure to maintain affordability and the widest possible access for populations that most need cervical cytology screening is greater than ever. ONGOING ISSUES: More data are required that would enable assessment of QA/C options with the clearest possible understanding of cost/benefits and current or new assumptions of risk. Other task forces, such as medicolegal, cost/benefit and those devoted to new technologies, are our essential partners in meeting the challenges described above.
Centers for Medicare and Medicaid Services, U.S.↗
Cytologic features of fibromatosis colli of infancy.
OBJECTIVE: To present the characteristic cytologic features of fibromatosis colli in infancy. STUDY DESIGN: A series of 14 children with the typical clinical presentation of fibromatosis colli of infancy on whom fine needle aspiration had been performed. RESULTS: The cytologic features were identical in all cases. All samples contained degenerated muscle cells in varying numbers, including multinucleated cells with abundant cytoplasm. Fibroblasts appeared mainly as single cells but with admixed clusters of varying sizes. The cells were slender, spindle shaped or somewhat rounded, with benign nuclear characteristics. CONCLUSION: In the typical clinical setting and with the cytologic findings above, surgical biopsy of the lesion may be avoided.
Biopsy, Needle↗