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151.
Diagnostic reliability of telepsychiatry in American Indian veterans   总被引:2,自引:0,他引:2  
OBJECTIVE: This study examined the reliability of the Structured Clinical Interview for DSM-III-R (SCID) in the administration of psychiatric assessments by real-time videoconferencing compared to face-to-face assessment within a rural American Indian community. METHOD: The SCID was administered to 53 male American Indian veterans who were randomly assigned over two separate occasions by different interviewers to face-to-face and real-time interactive videoconferencing within 2 weeks. Comparisons were made with prevalences, the McNemar test, and the kappa statistic. RESULTS: With the exception of past-year substance dependence and abuse/dependence combined, there were no significant differences between face-to-face and videoconference administration. The majority of kappas calculated (76%) indicated a good or fair level of agreement. Externalizing disorders tended to elicit greater concordance than internalizing disorders. CONCLUSIONS: Overall, SCID assessment by live interactive videoconferencing did not differ significantly from face-to-face assessment in this population. Videoconferencing is a viable vehicle for clinical and research purposes.  相似文献   
152.
Elevated circulating levels of soluble adhesion molecules as markers of endothelial dysfunction have been related to insulin resistance and its associated metabolic abnormalities. However, their associations with type 2 diabetes remain inconclusive. We conducted a prospective nested case-control study to examine the associations between plasma levels of E-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) and diabetes risk among 82,069 initially healthy women aged 50-79 years from the Women's Health Initiative Observational Study. During a median follow-up of 5.9 years, 1,584 incident diabetes case subjects were matched with 2,198 control subjects by age, ethnicity, clinical center, time of blood draw, and follow-up time. Baseline median levels of the biomarkers were each significantly higher among case subjects than among control subjects (E-selectin, 49 vs. 37 ng/ml; ICAM-1, 324 vs. 280 ng/ml; and VCAM-1, 765 vs. 696 ng/ml [all P values <0.001]). After adjustment for risk factors, the relative risks of diabetes among women in the highest quartile versus those in the lowest quartile were 3.46 for E-selectin (95% CI 2.56-4.68; P for trend <0.0001), 2.34 for ICAM-1 (1.75-3.13; P for trend <0.0001), and 1.48 for VCAM-1 (1.07-2.04; P for trend = 0.009). E-selectin and ICAM-1 remain significant in each ethnic group. In conclusion, higher levels of E-selectin and ICAM-1 were consistently associated with increased diabetes risk in a multiethnic cohort of U.S. postmenopausal women, implicating an etiological role of endothelial dysfunction in the pathogenesis of type 2 diabetes.  相似文献   
153.
The biological determinants of the phenotypic variation in sporadic Creutzfeldt-Jakob disease (sCJD) are unknown. To categorize sCJD cases, the prion protein (PrP) codon 129 genotype and the biochemical characteristics of the disease-associated form of PrP (PrPSc) can be combined to form six subgroups (MM1, MM2, MV1, MV2, VV1, and VV2). This classification largely correlates with the known variation in the clinical and pathological features of sCJD, with the MM1 and MV1 cases representing the “classic” phenotype of sCJD. To address how this classification relates to different strains of sCJD we have inoculated each subgroup of sCJD to a panel of mice expressing different forms of the human PRNP gene (129MM, 129VV, and 129MV). We have established that all subtypes are transmissible to at least one genotype of mouse, and both agent and host factors determine transmission efficiency and the form of PrPSc deposited in the brain. Moreover, we have identified four distinct strains of sCJD using our in vivo strain typing panel.  相似文献   
154.
BACKGROUND: The ideal technique for mesenteric division to create tension-free anastomoses has not been defined. For patients undergoing Roux-en-Y gastric bypass (RYGB), the mesenteric division technique was changed from stapler to bipolar sealing using LigaSure for cost reasons. This study aimed objectively to assess the impact of the mesenteric division method on mobilization length of the Roux limb in an animal model. Clinical complications related to Roux limb tension also were analyzed in the authors' population of RYGB patients. METHODS: Bowel and mesenteric divisions were performed in a porcine model. Four pigs received six to eight mesenteric divisions each. Steady force was applied for 1 min. The distances between the divided limbs of bowel were compared. To assess the clinical impact with RYGB patients, anastomotic complications were analyzed before and after incorporation of bipolar sealing in the authors' practice. RESULTS: In the porcine model, the length of mesenteric stretch averaged 93.7 mm with stapled division and 109 mm with bipolar sealing (p = 0.021). From a laparoscopic RYGB population, 160 patients with stapled division were included, all of whom were at least 1 year beyond their surgery. The study analyzed 792 patients with bipolar sealing for leak or bleeding and included 479 bipolar sealed patients more than 1 year beyond their surgery for analysis of their strictures. No difference in bleeding or leaks was found between these groups. The stricture rate was significantly different, with seven strictures after stapled division (4.37%) compared with one stricture after bipolar sealing (0.2%; p = 0.001). CONCLUSIONS: Bipolar sealing for mesenteric division is superior to stapling for optimization of enteric limb length at constant tension in a laboratory model. Clinical evidence supports this hypothesis with patients undergoing RYGB surgery by a decrease in the complications that can arise from Roux limb tension.  相似文献   
155.
Microarrays can be used to discover candidate genes associated with peripheral arterial disease (PAD) and develop models that predict patient clinical status. We hypothesize that multiple phenotypes of PAD with distinct patterns of gene expression exist. We histologically characterized and extracted ribonucleic acid from 31 arterial samples collected from the lower extremities of patients undergoing amputation or free fibular grafting. Analysis using the Affymetrix U133A microarray identified 335 genes with twofold or greater differences in expression between normal and diseased arteries (p< .01) and 104 genes with twofold or greater differences between diabetic and nondiabetic atherosclerotic arteries (p< .1). Many genes identified have known roles in inflammatory and lipid uptake pathways. Predictive models were developed that could predict PAD and the associated diabetic phenotype with an accuracy of 71 to 90%. Developing distinct genomic models of PAD will serve as the first step toward understanding the molecular and genetic basis of PAD and subsequent application of novel therapeutics to this condition.  相似文献   
156.
157.
Two unrelated cases of childhood peripheral neuroblastoma associated with infantile seizures and developmental problems (but without opsoclonus-myoclonus) are presented. The considerable body of evidence supporting the view that the opsoclonus-myoclonus syndrome associated with neuroblastoma has an immunologic basis is reviewed. Patients with neuroblastoma and opsoclonus-myoclonus syndrome commonly have subsequent developmental problems and, rarely, may have seizures. The authors postulate that the seizures and developmental problems in their two patients may result from an immunologic mechanism similar to that suggested for the opsoclonus-myoclonus syndrome of neuroblastoma. The only laboratory evidence to support an immunologic mechanism in these two patients was the presence of raised cerebrospinal fluid immunoglobulins in Patient 2. Specific antineuronal antibody tests in Patient 2 were negative. It is therefore possible that the association reported in these two unrelated cases is coincidental. However, reasonably extensive investigations did not uncover an alternative etiology for the presence of the seizures and developmental delay.  相似文献   
158.
A large number of heart transplants are performed annually in different transplant centers in the United States. This is partly because of the improved survival of patients who undergo cardiac transplantation, thus making it a more viable option in the management of end-stage heart failure. The survival benefit after heart transplantation is a result of newer immunosuppressive drug regimens and a better understanding of their effects and interactions. Several studies, mostly involving a small number of patients, describe use and comparison of the many distinct immunosuppressive drugs available to date. Interestingly, many transplant centers perform in-house typical induction treatment regimens because of their own experience and intra-institutional preference. This review summarizes current practices of immunosuppressive drug therapy in the first year post-heart transplant based on the available clinical evidence and discusses future options of heart transplant immunosuppressive drug therapies.  相似文献   
159.
Insulin-like growth factor (IGF)-I has growth-promoting effects on pancreatic cancer cells, and elevated fasting serum insulin has been linked to pancreatic cancer risk. IGF binding protein-1 (IGFBP-1) is a downstream target of insulin and inhibits IGF-I activity. To investigate whether prediagnostic plasma levels of IGFBP-1 are associated with pancreatic cancer risk, we did a prospective, case-control study nested within the Health Professionals Follow-up Study, the Nurses' Health Study, the Physicians' Health Study, and the Women's Health Initiative. We assayed circulating IGFBP-1 among 144 pancreatic cancer cases that occurred >or=4 years after plasma collection and in 429 controls, matched for date of birth, prospective cohort, smoking status, and fasting status. When compared with participants in the three highest quartiles of plasma IGFBP-1, those in the lowest quartile experienced a relative risk (RR) for pancreatic cancer of 2.07 [95% confidence intervals (95% CI), 1.26-3.39], after adjusting for other risk factors, including circulating IGF-I, IGF binding protein-3, and C-peptide. Only participants in the lowest quartile of plasma IGFBP-1 showed an elevated risk of pancreatic cancer. The influence of low plasma IGFBP-1 became progressively stronger with time; among cases diagnosed >or=8 years after blood collection, the adjusted RR was 3.47 (95% CI, 1.48-8.14), comparing the bottom versus the top three quartiles. The influence of plasma IGFBP-1 was most marked among participants who never smoked cigarettes (RR, 3.30; 95% CI, 1.48-7.35). Among participants in four U.S. prospective cohort studies, low plasma IGFBP-1 levels significantly predicted an increased risk of pancreatic cancer.  相似文献   
160.
Folate deficiency induces DNA breaks and may alter cellular capacity for mutation and epigenetic methylation. Few studies have examined the influence of one-carbon nutrients on pancreatic cancer risk, although recent studies suggest a potential protective effect for one-carbon nutrients from food sources, but not from supplements. We conducted a prospective nested case-control study to examine plasma concentrations of folate, vitamin B6 [whose main circulating form is pyridoxal-5'-phosphate (PLP)], vitamin B12, and homocysteine in relationship to pancreatic cancer, using four large prospective cohorts. Multivariable adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using conditional logistic regression. All statistical tests were two sided. Among 208 cases and 623 controls, we observed no association between folate, PLP, vitamin B12, or homocysteine and pancreatic cancer risk. Comparing the highest to lowest quartiles of plasma concentration, the ORs were 1.20 (95% CI, 0.76-1.91) for folate, 0.80 (95% CI, 0.51-1.25) for B6, 0.91 (95% CI, 0.57-1.46) for B12, and 1.43 (95% CI, 0.90-2.28) for homocysteine. In analyses restricted to nonusers of multivitamins, we observe a modest inverse trend between folate, PLP, and B12 and pancreatic cancer risk. In contrast, no such inverse associations were observed among study subjects who reported multivitamin supplement use. Among all participants, plasma levels of folate, B6, B12, and homocysteine were not associated with a significant reduction in the risk of pancreatic cancer. Among participants who obtain these factors exclusively through dietary sources, there may be an inverse relation between circulating folate, B6, and B12 and risk.  相似文献   
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