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PubMed2002

Thermal and pH changes, and dimensional stability in irreversible hydrocolloid impression material during setting.

Present study the relation between pH, thermal changes and dimensional stability during setting of irreversible hydrocolloid impression materials was investigated. Ten specimens of each product were prepared for different measurements: Thermal, pH changes and dimensional stability (mass and linear). Thermal and pH readings for 20 min and dimensional measurements for a 2 hr period were taken after mixing. It was observed that pH and thermal values changed in relation to different materials, while they did not change with the time according to variance analysis results. On the other hand, dimensional stability showed significant differences with time in all tested impression materials. A continuous pH change was observed with the time of gelation in all irreversible hydrocolloid impression materials tested. Dimensional stability also showed significant differences with time in all impression material and as a result hydrocolloids with a high pH showed better dimensional stability than those with a low pH.

Alginates↗
PubMed1984

Measurement of attenuation and scatterer spacing in human liver tissue: preliminary results.

A study measuring two quantitative parameters of human liver in vivo was performed to assess the reliability of measurement of the two parameters, and to evaluate their potential for diagnosing and grading diffuse fibrotic liver disease. The parameters measured were attenuation and "mean scatterer spacing," a measure of tissue structure. Components of variance analysis demonstrated that variation in the measured parameters was a function of the subject being examined, with significant variation noted between data acquisition sessions performed the same day. There was no significant additional variation of the measurements from week to week over a one-month period. A good correlation of the parameters with the severity of liver disease indicates that the technique may be useful in the clinical evaluation of diffuse liver disease.

Analysis of Variance↗
PubMed1999

[Evaluation of the effectiveness of radiotherapy in an Austrian-Hungarian collaboration].

To present an example of how to study and analyse the clinical practice and the quality of medical decision-making under daily routine working conditions in a radiotherapy department, with the aims of detecting deficiencies and improving the quality of patient care. Bimonthly audits (6 with a duration of 4-6 hours in each institution) were carried out by 3 auditors from the evaluating departments; they reviewed a total of 452 cases in Department A, and 265 cases in Department B. During the ongoing external audits, the qualifying parameters were (1) the sound foundation of the indication of radiotherapy, (2) the conformity to the institution protocol (3), the adequacy of the choice of radiation equipment, (4) the appropriateness of the treatment plan, and the correspondence of the latter with (5) the simulation and (6) verification films. Various degrees of deviation from the treatment principles were defined and scored on the basis of the concept of Horiot et al. (10), with some modifications. The action was regarded as adequate (score 1) in the event of no deviation or only a small deviation with presumably no alteration of the desired end-result of the treatment. A deviation adversely influencing the result of the therapy was considered a major deviation (score 3). Cases involving a minor deviation (score 2) were those only slightly affecting the therapeutic end-results, with effects between those of cases with scores 1 and 3. Non-performance of the necessary radiotherapeutic procedures was penalized by the highest score of 4. Statistical evaluation was performed with the BMDP software package, using variance analysis. Despite the comparable staffing and instrumental conditions, a markedly higher number (1.5 times) of new cases were treated in Department A, but with a lower quality of radiotherapy, as adequate values of qualifying parameters (1)-(6) were more frequent for the cases treated in Department B (85, 94%, 83%, 28%, 42% and 81%) than for those in Department A (67%, 83%, 88%, 26%, 33% and 18%). The responsible division (including staff and instrumentation), the responsible physician and the type of the disease each exerted a highly significant effect on the quality level of the treatment. Statistical analysis revealed a positive influence of the curative (relative to the palliative/symptomatic) intention of the treatment on the level of quality, but the effect of the first radiotherapy (relative to the second or further one) was statistically significant in only one department. The external audit related to the provision of radiotherapeutic care proved feasible with real valuation of the staff's activity.

Analysis of Variance↗
PubMed1999

[Analysis of decline in seminal fluid in the Italian population during the past 15 years].

BACKGROUND AND AIMS: The authors wished to study whether there has been a real decline in the quality of semen over the past years, as reported in the literature by a number of studies. This paper analyses the basic parameters of semen from 1068 males who have acted as donors during the past 15 years (1981-1995) for our semen bank. METHODS: Tables have been drawn up showing the number of cases examined every year, the mean concentration of spermatozoa, the mean percentage of mobile sperm and the mean percentage of non-conforming elements. RESULTS: An analysis of the data reported here shows that the mean concentration of spermatozoa in semen has shrunk from 88 x 10(6)/ml in 1981 to 61 x 10(6)/ml in 1995, a reduction of 30.7%; mean total motility has diminished from 74 to 66%, whereas the mean percentage with typical morphology has fallen from 76 to 63%. No statistical analysis was performed since variance analysis could not be performed on the sample in question to isolate the various sources of error. CONCLUSIONS: In conclusion, there has been a marked fall in the quality of semen over the past few years in individuals who regard themselves as fertile and are selected as semen donors. In the discussion the authors examine the various hypotheses regarding the possible causes of this deterioration in quality, opting for the argument based on the increased use of pollutants during the period in question in urban and rural areas.

Environmental Pollution↗
PubMedDate not supplied

[Evaluation of the diagnosis of pigmented tumors of the skin and factors leading to a decision to excise. Dermatologists of the Postgraduate Association of Haute-Normandie].

INTRODUCTION: The necessity of excising melanomas characterized by a slight thickness at an early stage, leads dermatologists to remove pigmented lesions which do not correspond to melanomas. The aims of this study were: a) to prospectively assess the accuracy of melanoma diagnosis, b) to quantify the number of excisions performed according to the degree of melanoma suspicion, c) to determine the specific clinical sign or signs of relevant diagnostic value. PATIENTS AND METHODS: This study was conducted prospectively from January 1996 to August 1997 by dermatologists in private practice and dermatologists from a University Hospital staff. When it was decided to excise a pigmented lesion, a form was filled out choosing the most appropriate clinical diagnosis, the degree of melanoma suspicion, and clinical signs which lead to surgery. Based on histological findings as the reference, the sensitivity, specificity, accuracy of melanoma diagnosis and the kappa test that evaluates the concordance between clinical and histological diagnosis, were performed. The diagnostic value of clinical signs was assessed by variance analysis. RESULTS: Of the 353 excised lesions, 38 (10.7 p. 100) were identified as melanoma on histologic examination. The sensitivity, the specificity and diagnostic accuracy were: 79 p. 100, 94 p. 100 and 53 p. 100 respectively. The kappa test concordance between clinical and histological diagnosis was 0.66. Two hundred and two lesions (57 p. 100) were excised even though the clinical suspicion of melanoma was poorly considered. Only one of these 202 lesions was identified histologically as a true melanoma. Thirty seven (24.5 p. 100) of the 151 remaining excised lesions with an "average" or "strong" suspicion were true melanomas. The clinical signs considered, alone or associated, had a poor predictive positive value (< 38 p. 100). An analytical approach performed with a logistic model permitted the identification of two associated signs suggesting a best diagnostic value. DISCUSSION: This is the only study, to our knowledge, reported in the literature which prospectively assesses the sensitivity, specificity and concordance between clinical and histological diagnosis of melanoma. Results were considered from average to good. The originality of this study was to assess the number of pigmented lesions excised according to the degree of melanoma suspicion, suggesting the possibility of reducing the number of nevi removed when the melanoma risk was considered clinically poor. Finally, this study emphasizes the limits of clinical semiology and the need for future diagnostic methods in the assessment of melanoma.

Adult↗
PubMed2000

Treatment of childhood acute immune thrombocytopenic purpura with high-dose methylprednisolone, intravenous immunoglobulin, or the combination of both.

OBJECTIVE: To compare the effectiveness of intravenous immunoglobulin (IVIG) alone, high dose methylprednisolone (HDMP) alone and the combination of IVIG and HDMP in the treatment of childhood immune thrombocytopenic purpura (ITP). BACKGROUND: Acute ITP in children is a self-limited disease with a benign course and low mortality rate. Patients with platelet count less than 20,000 x 10(9)/L are at increased risk of bleeding complications, making them candidates for treatment. METHOD: A 4 year retrospective study of 148 patients hospitalized with acute ITP was conducted to compare the effectiveness of HDMP vs IVIG vs the combination of IVIG/HDMP. Statistical methods used were descriptive statistics and variance analysis utilizing F distribution. RESULTS: The IVIG and the HDMP combination demonstrated to be superior to HDMP alone in raising the platelet count within the first 24 hours. The HDMP and IVIG combination was statistically a superior modality of treatment for patients with platelet count greater than 10,000 x 10(9)/L than was IVIG or HDMP alone. Intravenous immunoglobulin had the least effectiveness in patients with platelet count less then 10,000 x 10(9)/L within the first 24 hours. CONCLUSIONS: IVIG followed by the combination of HDMP and IVIG is the most effective therapeutic modality in rapidly increasing the platelet count to safe levels in children with acute ITP when compared to HDMP alone within the first 24 hours. For borderline low platelet count (> 10,000 x 10(9)/L) HDMP and IVIG was superior to IVIG alone.

Acute Disease↗
PubMedDate not supplied

[Conventional electroencephalography and delirium].

OBJECTIVE: To review the electroencephalographic changes in conventional tracings made in patients with an acute attack of delirium described in the literature. PATIENTS AND METHODS: These alterations are considered in a sub-sample of 60 patients randomly selected from a sample of 223 persons admitted to hospital for different medical and surgical conditions and seen in psychiatric consultation for delirium during the years 1996 and 1997 in the Hospital General Yagüe in Burgos, Spain. The methods used included a conventional EEG tracing, following the usual clinical technique, in the context of a prospective, observational study. The changes were classified according to the trace seen and overall criterion of the neurophysiologist. The results were compared with simple statistical tests (frequency and percentage counts, chi squared and residual contingency tables, average comparisons and unidirectional Anova variance analysis and Bonferroni post hoc test). RESULTS: Marked alterations of tracings were seen in 83.3% of cases (78.7% 'slight', 'moderate' and 'excessive' slowing and 6.6% 'rapid' anomalies. Statistically, 'multi-factorial' and 'on dementia' types of delirium (characterized on the electroencephalogram by different degrees of slowing of the recording) could be clearly differentiated from delirium due to abstinence from alcohol which was mainly seen with 'fast' recordings. CONCLUSION: It was confirmed that there are two distinct types of delirium which are very different from the electroencephalographic point of view.

Acute Disease↗
PubMed1999

Tenorrhaphy and tendinous venous envelope (TVE). A morphofunctional study in 24 beagles dogs.

A morphofunctional study was undertaken in 24 Beagle dogs subjected to a a tenorrhaphy, in order to evaluate the results obtained with 3 different surgical procedures (16 hands each)--"traditional" (TRAD); the "tendinous venous envelope" (TVE), and the "simulated procedure" (SHAM). The surgical tissue (n = 48) was the extensor digitorum communis muscle of the hand (forepaw) bilaterally. For TRAD procedure, the Bunnell suture technique was applied. For the TVE procedure, the tenorrhaphy site was wrapped in a segment of autologous femoral vein and for the SHAM procedure, the tendon was exposed over 3 cm without sectioning it and the wound was closed. In each case, the limb was immobilised for 21 days in a cast. Functional data (288 X-rays) was obtained on angle variations of the radio-carpal joint in 2 different positions--passive (physiological), and forced (with an additional weight of 150 g). For each position, the angle variation obtained for each one of the surgical procedures were compared at 3 different times: day zero (surgical intervention), day 21 (cast removal), and day 35 (surgical tissue removal). Morphological data (144 sections) was obtained by analyzing the surgical tissue (tendinous fibrosis; fusion of the tendon clusters with the epimysium and the neighboring tissues; synovitis and the virtual space between the tendon and the neosheath). Tests of variance analysis by posts (critical H = 5.99), showed that the TVE procedure produced better results as compared to TRAD (SHAM approximately equal to TVE > TRAD) on day 21 (H = 22.58) as well as on day 35 (H = 8.08).

Analysis of Variance↗
PubMed2000

[Relationship between leptin and insulin blood levels in obese and lean Chilean women].

BACKGROUND: Leptin, a product of ob gene and insulin blood levels, are proportional to the amount of adipose tissue. Insulin could have an independent regulatory effect on leptin secretion. AIM: To assess the relationship between serum leptin and plasma insulin levels in obese and lean Chilean women. MATERIAL AND METHODS: One hundred forty five women, aged 20 to 60 years old, were studied. Weight, height, waist and hip circumference, fasting blood glucose, insulin and leptin levels were measured. Insulin resistance was assessed using the homeostasis model assessment. The relationship between different variables was determined using multiple linear regression, variance analysis and non parametric correlation. RESULTS: Leptin serum concentrations were positively correlated with body mass index, insulin plasma levels and degree of insulin resistance. The association of leptin with insulin was independent of body mass index and persisted after adjustments by body fat distribution and age. CONCLUSIONS: Insulin and insulin resistance are associated to high blood leptin levels and this association is independent of the degree of adiposity and body fat distribution.

Adult↗
PubMed1975

Effects of Demetrin on circulation.

In a double-blind study the influence of Demetrin on cardiovascular activity was investigated. Basic values before treatment were compared with values after 1 and 2 weeks' administration. The cardiovascular parameters "pulse rate" and "blood pressure" were studied in the orthostatic tolerance test (pivoting table) and in the bicycle ergometer test. Results were evaluated with variance analysis. Demetrin at dosage levels of 3 x 10 mg/day and 3 x 20 mg/day did not influence cardiovascular function. Occasionally mild sedation was observed.

Analysis of Variance↗
PubMed1975

[Psychological studies of a long-term treatment of the neurovascular syndrom with Trivastal (author's tranls)].

With Trivastal, a double blind study including placebo control was carried out with 66 patients at the age between 55 and 67. These persons were patients of several practioners and were treated because of different phenomena of the neurovascular psychosyndrome. They received 1 dragee daily at the beginning of the treatment, then additional dragees up to the amount of 3, 4 and 5 (or 6 according to the case) over a period of 14 weeks. The control of efficiency consisted in 13 psychometrical measurements: Measurement of reaction time, flicker fusion test, "fluency"-tests according to Guilford, self rating scale for the measurement of general psycho-physical condition, several tests for the control of memory functions, projective tests to determine emotional factors and a semi-standardized interview for the control of subjective symptoms of the neurovascular psychosyndrome. Data were evaluated by variance analysis and covariance analysis. Trivastal improved the cerebral metabolism, so that the treatment resulted in an improvement of vigilance and of psychomotor functions, in a better adaptation to demands of everyday affairs and in a higher efficiency of different memory functions. Finally, the patients returned to a normal level of psychic behaviour and managed their social integration more easily.

Aged↗
PubMed2000

[Physicochemical and microbiological evaluation of 3 commercial guava jams (Psidium guajava L.)].

Four different production batches were taken from each brand. Samples were purchased from retail markets in Maracay, Cagua and Turmero. (Venezuela). The average physical and chemical values were: vacuum = 38.81 cm Hg; pH = 3.28; titrable acidity (%citric acid) = 0.59%; degree Brix = 67.24; reducing sugars = 55.28%; total sugars = 62.28, and the color parameters a = +14.44, b = +8.77 and L = 17.09. Molds, yeast and aerobic plate counts were lower than 10 UFC/g; it reveals an excellent microbiological quality of the product. The studied jams degree Brix and acidity fulfil COVENIN (1) requirements for jam products, but not pH range. In agreement with variance analysis, there were highly significance differences between the samples and among the shares of each sample for all physical and chemical properties evaluated.

Analysis of Variance↗
PubMed2002

[Lung volume reduction surgery for emphysema. Long term results].

We prospectively analyzed 19 patients submitted to lung volume reduction surgery (LVRS). Mean age 54 years. Fourteen patients, with predominant emphysema of upper lobes, were approached through a median sternotomy. Five patients with predominant lower lobes lesions, were approached through a bilateral anterolateral thoracotomy. Surgery consisted in resection of 20 to 30% of lung volume corresponding to areas of severe parenchymal destruction by stapling suture additioned with bovine pericardium. Changes in lung function and physical performance were evaluated by FEV1, FVC and RV, 6 minutes walk test and dyspnea index according to Medical Research Council at 3, 12, 24, 36 and 48 months. Variance analysis with correction of Bonferroni was performed. One patient died of acute myocardial infarction. There was a significant average improvement in all parameters measured at 3, 12, 24 and 36 months with regard to preoperative values. Comparing the preoperative and 3 months values, there was an increment in FEV1 from 0.94 +/- 0.37 (31% of predicted) to 1.35 +/- 0.40 L (45%) (p < 0.05), in FVC from 2.24 +/- 0.69 (54%) to 3.05 +/- 0.80 L (75%) (p < 0.05) and in 6 minutes walk test from 395 +/- 66 to 517 +/- 50 mts (p < 0.001). There was also a decrease in the RV of 4.78 +/- 1.14 L (284%) to 3 +/- 0.68 L (180%) (p < 0.001) and in dyspnea index of 3.34 +/- 0.82 to 0.53 +/- 0.53 (p < 0.001). The percentage of average increment in FEV1 was 53% at 3 months (n = 18), 72% at 12 months (n = 13), 58% at 24 months (n = 10), 53% at 36 months (n = 6) and 60% at 48 months (n = 3). LVRS can be performed with acceptable morbidity and mortality in highly selected emphysematous patients. Decrease of dyspnea and improvement in physical performance reach a maximum between 3 and 12 months and may remain so after four years.

Adult↗
PubMed2002

The mastectomy clinical pathway: what has it achieved?

INTRODUCTION: The mastectomy clinical pathway was developed to optimise the clinical care and cost management of breast cancer patients. The aim of this study was to prospectively assess the effect of the mastectomy pathway at the National University Hospital, Singapore over a 7-month period. MATERIALS AND METHODS: A prospective study was carried out on all breast cancer patients admitted for elective mastectomy between March and October 2001. As surrogates of optimised cost and care management, the length of stay and hospital costs, as well as the incidence of complications and unscheduled readmissions, were analysed. Non-pathway mastectomy patients treated from March to October 2000 were used as controls. A total of 83 patients who underwent mastectomy formed the pathway group, while 69 non-pathway patients acted as controls. RESULTS: Compared to controls, the mean length of hospital stay decreased significantly from 4.91 days to 4.10 days (P = 0.018) and the mean cost per case decreased significantly from $5,050 to $4,406 (P = 0.014) for those in the pathway group. There were no significant differences in the complications and unscheduled hospital readmission rates between the two groups (P > 0.05). CONCLUSION: The implementation of mastectomy clinical pathway has improved consistency in patient's treatment, the quality of patient outcome, and has reduced the costs of care and length of hospital stay. In addition, variance analysis of the mastectomy pathway has shown to be valuable for problem identification to improve patient care.

Adult↗
PubMed2002

Evaluation of apical leakage of root canals obturated with Nd: YAG laser-softened gutta-percha, System-B, and lateral condensation techniques.

In endodontics, a laser can be used as a heat source and gutta-percha can be softened by a laser and used in the root canals. The System-B endodontic heat source unit was designed for the obturation of the root canal system with a single continuous wave of thermoplasticized gutta-percha. The aim of this study was to compare the apical leakage of lateral condensation; Nd: YAG laser-softened gutta-percha and System-B techniques. Fifty-five extracted, single root human maxillary anterior and premolar teeth were used in this study. After working length determination, the "step-back technique" was used to prepare the root canals. The teeth were randomly divided into three experimental groups of 15 each and two control groups of 5 specimens each. The first group was obturated by lateral condensation, the second group by gutta-percha softened with an Nd: YAG laser, and the third group was obturated using the System-B technique. Apical leakage of the roots was evaluated by dye penetration using a stereomicroscope after sectioning the roots. The results of the first and third groups were similar, and the results of the second group showed differences when compared with the other groups. However, variance analysis revealed there was no statistically significant difference among the results.

Analysis of Variance↗
PubMedDate not supplied

[Acid hydrolysis of mandioca].

The influence of time of hydrolysis, pression of the process, ratio of mass of flour and volume and concentration of the acid solution was studied in the hydrolytic processes for Cassava flour. The aim was to obtain fermentable sugars, and the results were submitted to variance analysis.

Analysis of Variance↗
PubMed2002

Rice brown spot and susceptibility of some cultivars in north of Iran.

Rice brown spot is one of the important diseases in the world including Iran. 91 samples of the infected plants such as leaves and panicles were collected from different locations of Guilan province, North of Iran and the fungi isolated and studied for pathogenicity. Three species of Bipolaris (B. oryzae, Bipolaris sp. and B. cf. victoriae) were isolated more than other species with serious effects on the plants respectively. Reactions of 8 cultivars of rice, Neda, Nemat, Sepeed-rood, Bejar, Khazar, Domsephid, Hassan-saraee and Binam were studied in greenhouse to Bipolaris sp. and B. cf. victoriae in two stages of growth, on leaves and panicles, respectively. The results showed that in seedling stage on leaf there was no significant difference between these cultivars in case of infection rates. In heading stage, although there was no significant difference according to variance analysis, but according to Duncan test (5%) they could be divided into 3 groups. Neda, Sepeed-rood, Khazar and Binam, with the lowest infection rate, were in the first group Bejar, Domsephid and Hassan-saraee were classified into the second group and Nemat was in the third one. Curvularia sp., Nigrospora sp., Pyricularia grisea and Alternaria sp. were with minor prevalence in infection of the plants.

Analysis of Variance↗