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21.
Background
To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS). 相似文献22.
Sparks DL Connor DJ Browne P Sabbagh MN;AD Cholesterol-Lowering Treatment Trial Team 《Journal of molecular neuroscience : MN》2002,19(1-2):209-212
Elevated circulating cholesterol can have profound effects on the health of an individual. Such excess cholesterol can promote
coronary artery disease, production and accumulation of β-amyloid in the brain, and possibly Alzheimer’s disease (AD). In
a clinical trial evaluating the benefit of a cholesterol-lowering drug in the treatment of AD, mean cholesterol levels at
baseline among individuals participating in the trial were found to be relatively high. Based on this observation we suggest
that cholesterol levels should be actively monitored in the elderly, as many individuals with AD are over 65 years of age
and therefore excluded by currently accepted guidelines. 相似文献
23.
SE Daley AD Pearson AW Craft J Kernahan RA Wyllie L Price C Brock C Hetherington D Halliday K Bartlett 《Archives of disease in childhood》1996,75(4):273-281
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover. 相似文献
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Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury. 相似文献
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28.
Differential effects of MK801 and lorazepam on heart rate variability in adolescent rhesus monkeys (macaca mulatta) 总被引:3,自引:0,他引:3
Previous research shows that ketamine significantly alters cardiac signal regulation in rhesus monkeys, however relatively little is known about the mechanism for this effect. In the study reported here the relative contributions of NMDA receptor activation on cardiac signal dynamics were determined by administering a specific NMDA antagonist, MK801, to rhesus monkeys. The general effects of sedation were assessed by measuring cardiac response to lorazepam, a sedative drug without direct NMDA receptor activity. Electrocardiographic signal dynamics were examined before and after I.V. administration of either MK801 (0.16 mg/kg) or lorazepam (0.48 mg/kg). Inter-beat interval time series data were analyzed in the frequency domain after Fourier transform, and a nonlinear measure of autocorrelation, the Hurst exponent (H), was derived. After MK801 administration, log [HF /Total power] increased post-infusion (M = 1.11, SD = 0.45) compared with pre-infusion values [M = -0.19, SD = 0.32, F(1,4) = 19.49, P = 0.01] while H decreased, mean pre versus post 0.52+/-S.D. 0.10 versus 0.01+/- 0.05, P = 0.0002. Lorazepam administration did not significantly alter heart rate variability measures obtained in the frequency or nonlinear domains. To our knowledge, this is the first study that has defined the effects of peripherally administered MK801 on cardiovascular dynamics in primates and establishes that peripheral administration of NMDA antagonists result in large increases the high-frequency components of cardiac rhythm and increased heart rate variability compatible with MK801-associated increases in parasympathetic outflow. 相似文献
29.
Histopathologic score predicts recurrence free survival after radical surgery in patients with stage IA2-IB1-2 cervical carcinoma 总被引:5,自引:0,他引:5
Grisaru DA Covens A Franssen E Chapman W Shaw P Colgan T Murphy J DePetrillo D Lickrish G Laframboise S Rosen B 《Cancer》2003,97(8):1904-1908
BACKGROUND: The authors evaluated clinical and pathologic factors that predicted for recurrence after patients underwent radical surgery for International Federation of Gynecology and Obstetrics (FIGO) Stage IA(2)-IB(1-2) cervical carcinoma and developed a simple method of scoring those predictive factors to quantify outcome. METHODS: An analysis was conducted of a prospective radical surgery cervical carcinoma data base. A Cox proportional hazards regression analysis was done for each of the individual factors to estimate individual risk ratios using all available data for each factor. Stepwise and best-model options were used to identify the best combinations as predictors and to calculate adjusted risk ratios. Based on the information obtained, each patient was assigned a categorical score to predict recurrence. The variables used for the score were dichotomized. The differences between the scores in time to recurrence were evaluated using the log-rank test to compare the time to recurrence curves that were generated with the Kaplan-Meier method. RESULTS: Eight hundred seventy-one patients were included in the study, and 66 patients who developed recurrent disease after a median follow-up of 49 months. Tumor size, maximum depth of invasion, pelvic lymph node status, tumor grade, and capillary lymphatic space (CLS) were single predictors for recurrence, and the score, which was based on combinations of these factors, predicted the disease free survival. Maximum depth of invasion, pelvic lymph node status, and CLS were the best combined predictors for recurrence, and they were used to form a second, precise scoring system to predict disease free survival (P < 0.0001; log-rank test). CONCLUSIONS: The scoring system based on maximal depth of invasion, CLS, and pelvic lymph node metastases identified four strata of patients with distinct recurrence free survival. The incremental presence of each factor decreased recurrence free survival after patients underwent radical surgery. Patients with the presence of all three factors had a 5-year recurrence free survival rate of 65%. These patients would be suitable for studies of postoperative adjuvant therapy to improve outcome. 相似文献
30.
Mammary intraepithelial neoplasia outgrowths (MINO): MINO and human ductal carcinoma <Emphasis Type="Italic">in situ</Emphasis> 总被引:1,自引:0,他引:1 下载免费PDF全文
Germ-line mutations in the BRCA1 tumour suppressor gene contribute to familial breast tumour formation, but there is no evidence for direct mutation of the BRCA1 gene in the sporadic form of the disease. In contrast, decreased expression of the BRCA1 gene has been shown to be common in sporadic tumours, and the magnitude of the decrease correlates with disease progression. BRCA1 expression is also tightly regulated during normal breast development. Determining how these developmental regulators of BRCA1 expression are co-opted during breast tumourigenesis could lead to a better understanding of sporadic breast cancer aetiology and the generation of novel therapeutic strategies aimed at preventing sporadic breast tumour progression. 相似文献