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971.
W Naidong RH Pullen RF Arrendale JJ Brennan JD Hulse JW Lee 《Canadian Metallurgical Quarterly》1996,14(3):325-337
Fifty-one young diabetics responded to a questionnaire concerning compliance and were interviewed on two topics: the meaning of care to the subjects and the nature of their support system. Diabetes control was measured by glycosylated haemoglobin (GHB). Interview data were analysed by continuous comparative analyses. The categories obtained were quantified and the relationship between variables analysed by cross tabulation, chi-square test and discriminant analysis. Those who responded with a good compliance showed good control of diabetes as indicated by GHB values and reported sufficient energy and will-power to implement the health regimens. Those young people who reported that they had sufficient energy and will-power considered care important, received encouragement, felt that care brings well-being and had no fears of complications. 相似文献
972.
JG Johnson JB Williams RR Goetz JG Rabkin JD Lipsitz RH Remien 《Canadian Metallurgical Quarterly》1997,106(1):154-158
A longitudinal study was conducted to investigate the stability of personality disorders (PDs) over a 2-year interval, as well as the association between change in PD symptomatology and change in psychological distress. Structured clinical interviews and questionnaires assessing PDs and psychological distress were administered to a community sample of 118 gay men (80 HIV seropositive men and 38 HIV seronegative men) at a baseline session and readministered 2 years later. Results indicated that PD symptom levels tended to be moderately stable, that PD diagnoses had low stability and that changes in PD symptom levels were associated with changing levels of psychological distress but not with progression of HIV infection. 相似文献
973.
W Linz RH Becker BA Sch?lkens G Wiemer M Keil KH Langer 《Canadian Metallurgical Quarterly》1998,54(6):2037-2044
BACKGROUND: The effect of life-long treatment with the ACE inhibitor ramipril on hypertension-induced histological changes in the kidney was tested in stroke-prone spontaneously hypertensive rats (SHR-SP). METHODS: One-month-old pre-hypertensive SHR-SP were randomized into three groups of 45 animals each, and exposed via drinking water for their lifetime to a dose of: 1 mg.kg-1.d-1 ramipril (antihypertensive dose, HRA); 10 micrograms.kg-1.d-1 slight dose of ramipril (non-antihypertensive dose, LRA); or placebo. Histological and biochemical assessments were conducted after 15 months in ten rats each, when about 80% of the placebo group had died. RESULTS: Kidneys from placebo treated SHR-SP showed pronounced arterial wall hypertrophy and sclerosis, arterial fibrinoid necrosis, glomerulopathy and tubular interstitial injury that were, in concert with normalized blood pressure, completely prevented by HRA treatment. LRA treatment did not affect any blood pressure increase, and also attenuated the development of arterial wall hypertrophy, sclerosis and arterial fibrinoid necrosis, though to a minor extent only, but did not change glomerular and tubulointerstitial degeneration. These effects of ramipril were associated with a dose-dependent inhibition of plasma and renal tissue ACE activities as well as lower serum concentrations of creatinine, but there were no changes in serum potassium. CONCLUSIONS: Life-long HRA-induced ACE inhibition protects against hypertension-induced renal damages in SHR-SP. This is associated with a doubling of the lifespan in these animals. 相似文献
974.
RH Jacobson 《Canadian Metallurgical Quarterly》1998,17(2):469-526
Assay validation is a series of the following interrelated processes: an experimental process: reagents and protocols are optimised by experimentation to detect the analyte with accuracy and precision, and to ensure repeatability and reproducibility in the assay. a relative process: its diagnostic sensitivity and diagnostic specificity are calculated relative to test results obtained from reference animal populations of known infection/exposure status. a conditional process: classification of animals in the target population as infected or uninfected is conditional upon how well the reference animal population used to validate the assay represents the population to which the assay will be applied (accurate predictions of the infection status of animals from test results and predictive values of positive and negative test results are conditional upon the estimated prevalence of disease/infection in the target population) an incremental process: confidence in the validity of an assay increases over time when use confirms that it is robust as demonstrated by accurate and precise results (the assay may also achieve increasing levels of validity as it is upgraded and extended by adding reference populations of known infection status) a continuous process: the assay remains valid only insofar as the assay continues to provide accurate and precise results as proved through statistical verification. Therefore, validation of diagnostic assays for infectious diseases does not end with a time-limited series of experiments based on a few reference samples. Rather, it is a process that also requires constant vigilance and maintenance, along with reassessment of its performance characteristics for each population of animals to which it is applied. It is certain that the current movement to develop and implement accreditation criteria for veterinary diagnostic laboratories may be of little worth unless there is some assurance that the assays conducted in such laboratories are properly validated. Fully accredited laboratories may generate highly reproducible test results, but the results may still misclassify animals as to their infection status due to an improper assay validation process. Therefore, assay validation is foundational to the core product of veterinary diagnostic laboratories--test results and their interpretation. 相似文献
975.
976.
RH Christenson SH Duh LK Newby EM Ohman RM Califf CB Granger S Peck KS Pieper PW Armstrong HA Katus EJ Topol 《Canadian Metallurgical Quarterly》1998,44(3):494-501
We compared cardiac troponins T (cTnT) and I (cTnI) collected within 3.5 h of ischemic symptoms for predicting clinical outcomes in 770 patients. cTnT (cutoff > 0.1 microgram/L) and cTnI (cutoff > 1.5 micrograms/L) were concordant (both positive or negative) in 90.4% of patients. Among discordant results, 66 were cTnT positive and cTnI negative vs 8 who showed the reverse (P < 0.001). Five cTnT-positive and cTnI-negative patients died within 30 days; none who were cTnT negative and cTnI positive died. cTnT showed a slightly greater association (chi 2 = 18.0, P < 0.001) with 30-day mortality than cTnI (chi 2 = 12.5, P = 0.002). The area of the ROC curve for predicting 30-day mortality was significantly larger (Z = 2.08; P = 0.0375) for cTnT, at 0.68 [95% confidence interval (CI) 0.60-0.75], compared with cTnI, at 0.64 (95% CI 0.56-0.72). When cTnI and the electrocardiogram (ECG) were put in a logistic multiple regression model, cTnT added significant information (chi 2 = 8.03, P = 0.045); however, cTnI did not add to a model containing cTnT and the ECG (chi 2 = 0.84, P = 0.657). cTnT provided more information than cTnI for predicting 30-day mortality early after presentation with acute coronary syndromes. 相似文献
977.
BACKGROUND: To evaluate the implementation of nuchal translucency measurement as an additional examination within the first trimester routine ultrasound in an unselected population of women. METHODS: A prospective study in which all pregnant women during 1994, referred for the first trimester routine ultrasound scan, were asked to participate. Of a total of 1852 women with a viable pregnancy, results from 1444 women were evaluated. When a nuchal translucency of 4 mm or more was found, the woman was offered both a genetic amniocentesis in gestational week 13-15 and an additional ultrasound examination in gestational week 18-19. RESULTS: Six fetuses had a nuchal translucency of 4 mm or more and none of these had any chromosomal abnormality. Neither had any of the fetuses in the study, karyotyped for other reasons, any chromosomal defect and nor was there any child born with aneuploidy in the study population. No strong relation between major malformations e.g. abnormalities of the heart and increased nuchal translucency was found. The fetus with the largest nuchal translucency (=6 mm) was born healthy. CONCLUSION: The efficacy of nuchal translucency measurement needs further evaluation before it can be introduced as a screening method in an unselected pregnant population. 相似文献
978.
EK George ML Mearin SM Kanhai HC Franken RH Houwen RA Hirasing JP Vandenbroucke 《Canadian Metallurgical Quarterly》1998,142(15):850-854
OBJECTIVE: To assess the incidence of childhood coeliac disease in the Netherlands and to study the clinical features. DESIGN: Prospective. SETTING: Leiden University Medical Centre, Leiden, the Netherlands. METHOD: Cases of childhood coeliac disease in the Netherlands in 1993-1995 were identified by means of the Dutch Paediatric Surveillance Unit. Inclusion criteria were: birth in the Netherlands, diagnosis with at least one small bowel biopsy in 1993-1995 and age at diagnosis 0-14 years. The data were cross checked with the Dutch Network and National Database of Pathology and compared with data from a previous study on childhood coeliac disease, 1975-1990. RESULTS: 297 Coeliac patients were identified by means of the Surveillance Unit, another 32 through the National Database of Pathology. The mean crude incidence rate of diagnosed childhood coeliac disease was 0.51/1000 live births, which was in the range of rates found in other West European countries and significantly higher than the mean crude incidence rate of 0.18/1000 live births found in the Netherlands in 1975-1990. The clinical presentation was classic up to 1990: chronic diarrhoea, abdominal distention and growth failure. From 1993 onward, however, the number of children with chronic diarrhoea and abdominal distention decreased significantly and the number with weight loss, anaemia and abdominal pain increased. Associated disorders were present in 13.7% of the cases. CONCLUSIONS: The incidence of diagnosed childhood coeliac disease in the Netherlands showed a tendency to increase significantly during the past decade. In a period of 20 years a significant trend toward change in the clinical presentation of coeliac disease in Dutch children was observed. 相似文献
979.
980.
Perry D. Haaland John C. Lusth Roger F. Liddle Joan W. Curry 《Annals of Mathematics and Artificial Intelligence》1990,2(1-4):179-195
As a means of increasing the quality and productivity of R&D efforts, we provide an integrated collection of experimental design tools for use by researchers at the Becton Dickinson Research Center. The bases for these tools are a set of well-accepted guidelines for experimental procedures and a tabulation of practical experimental designs. The designs themselves are provided to researchers in an easy-to-use personal computer (PC) spreadsheet format. The data can then be easily exported to a commercial PC statistics package. A PC based expert system, called Dexter, assists researchers in following the guidelines for selecting which of the tabulated designs should be used for a given experiment.Dexter incorporates the expertise of a consulting statistician in helping a user select a design from among 35 designs for industrial screening experiments. The designs considered include from three to eleven experimental factors with a maximum sample size of 32 runs. The evaluation is based on the calculation of design scores which model guidelines for selecting experimental designs. A graph isomorphism algorithm is used to match particular design characteristics such as estimable two-factor interactions. Smart search techniques and precomputing of graph representations minimize run times and make the PC platform practical. The window-oriented, menu-driven interface is intuitive and easy-to use. 相似文献