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羁押人员HIV感染状况及行为学调查   总被引:2,自引:0,他引:2  
目的了解羁押人员HIV感染现状以及相关高危行为情况,为制定艾滋病防治措施和决策提供科学依据。方法使用描述性研究方法对2381名羁押人员的人群特征以及HIV感染的血清流行病学调查资料进行综合分析。结果共发现HIV抗体阳性3例,阳性率1.26‰;注射吸毒、性乱、有偿供血史的分别占2.18%、30.28%、0.59%。结论羁押人员高危行为发生率较高,应尽快采取健康教育、行为干预和相应监管措施。  相似文献   
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Summary HIT is a hamster-derived beta-cell line which in contrast to normal beta cells that only express the high Km GLUT-2 glucose transporter, also expresses the low Km glucose transporter GLUT 1. In HIT cells the abnormal glucose transport mechanism is associated with a marked shift to the left of the glucose-induced insulin release dose-response curve. We have used this cell model to investigate whether changes in glucose transport affect the glucose-induced insulin release. HIT cells were first incubated with a concentration of cytochalasin B (0.4 mol/l) that selectively inhibits the GLUT-1 but not the GLUT-2 transporter. The consequences of blocking glucose phosphorylation and insulin release were studied. Exposure to 0.4 mol/l cytochalasin B for 1 h caused a selective loss of the low Km transport: the calculated Vmax of GLUT 1 was reduced from 1726±98 to 184±14 pmol · mg protein–1 5 min–1 (mean±SEM, n=6, p<0.005), while no major difference in the high Km (GLUT-2) transport was observed. In cytochalasin B exposed HIT cells the glucose phosphorylating activity (due to hexokinase and glucokinase) was unaffected. In these cells, however, the dose-response curve of glucose-induced insulin release was significantly shifted to the right: the 50% of maximal response (increment over baseline) was reached at an average glucose concentration of 2.9±0.2 mmol/l (vs 0.6±0.01 mmol/l in control HIT cells mean±SE, n=5, p<0.05) and the maximal effect was reached at 11.0 mmol/l glucose (vs 2.8 mmol/l in control HIT cells p<0.005). These results are consistent with the hypothesis that the affinity of the glucose transport system may contribute to determination of the glucose threshold concentration that triggers insulin secretion.  相似文献   
4.
Single crystal silicon solar cells are still predominant in the market due to the abundance of silicon on earth and their acceptable efficiency. Different solar-cell structures of single crystalline Si have been investigated to boost efficiency; the heterojunction with intrinsic thin layer (HIT) structure is currently the leading technology. The record efficiency values of state-of-the art HIT solar cells have always been based on n-type single-crystalline Si wafers. Improving the efficiency of cells based on p-type single-crystalline Si wafers could provide broader options for the development of HIT solar cells. In this study, we varied the thickness of intrinsic hydrogenated amorphous Si layer to improve the efficiency of HIT solar cells on p-type Si wafers.  相似文献   
5.
Summary Glucose and insulin are generally considered to express opposite effects on insulin synthesis and secretion from pancreatic islets. For the most part this generalization has arisen from short-term experiments. Our studies focused on the chronic, long-term effects of variable insulin concentrations on insulin gene expression and secretion in cultures of HIT-T15 cells. From passage 70, HIT cells were split and passed weekly for 25 weeks in media containing either (A) 11.1 mmol/l glucose with no insulin added; (B) 11.1 mmol/l glucose with insulin added to maintain a level of approximately 4,000 U/ml; (C) 0.8 mmol/l glucose with no insulin added; (D) 0.8 mmol/l glucose with insulin added to maintain a level of approximately 4,000 U/ml; and (E) 0.8 mmol/l glucose with progressively less insulin added over time to mimic the gradual decrease in media insulin levels found in condition A. Our data indicate that during chronic passing of HIT cells, addition of exogenous insulin led to preserved levels of insulin mRNA, insulin content and insulin secretion in cells cultured in media containing 11.1 mmol/l glucose concentration. However, in media containing 0.8 mmol/l glucose concentration, addition of insulin diminished the levels of insulin mRNA, insulin content and insulin secretion. Nonetheless, in all cases exogenously added insulin sustained greater levels of insulin mRNA, insulin content and insulin secretion than the instance wherein media containing a high concentration of glucose only was used. These results indicate that short-term experiments assessing the effects of insulin on beta-cell function do not necessarily apply to chronic, more long-term experiments in which insulin can have variable time- and concentration-dependent effects on insulin gene expression and secretion.Abbreviations HIT Hamster insulin-secreting tumour  相似文献   
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Objective – To evaluate 12‐week changes from baseline of 2 disease‐specific patient‐reported outcome (PRO) measures in adults with migraine treated with galcanezumab, an investigational humanized antibody binding calcitonin gene‐related peptide (CGRP), or placebo. Background – Preventing headache‐related functional impairment is an important goal of migraine preventive treatment and a measurement target for PROs. Understanding which drugs have the potential to improve patient functioning in addition to preventing migraine headaches is vital to lessening patient burden. Design/Methods – This Phase 2b double‐blind, randomized, placebo‐controlled study enrolled adults with episodic migraine. Galcanezumab (120 mg subcutaneous injection; n = 60) or placebo (n = 127) was administered every 28 days for 12 weeks. Post hoc secondary analyses were conducted for those who completed 12 weeks of treatment on 2 PROs: The Migraine‐Specific Quality of Life Questionnaire (MSQ) v2.1 and the Headache Impact Test? (HIT‐6). Results – Analysis of covariance revealed significant differences in least square mean changes from baseline between galcanezumab and placebo for all MSQ domains including total mean change placebo of 18.63, galcanezumab of 27.36 (95% CI 2.449, 15.008; P‐value of .0067); Role Function‐Restrictive mean change placebo of 22.40, galcanezumab of 31.92 (95% CI 2.636, 16.518; P‐value of .0071); Role Function‐Preventive mean change placebo of 13.43, galcanezumab of 19.76 (95% CI 0.476, 12.185; P‐value of .0342); and Emotional Function mean change placebo of 16.88, galcanezumab of 26.61 (95% CI 2.789, 16.674; P‐value of .0063). At baseline, mean number of migraine headache days (MHDs) did not correlate with MSQ total scores or HIT‐6. At 12 weeks post‐treatment, MHD correlated with MSQ and HIT‐6 scores (all < .0001). Change in MHD was associated with change in MSQ domains and change in HIT‐6 scores (all < .0001). Conclusions – In comparison with placebo, treatment with galcanezumab was associated with significant functional improvements as reflected by changes in MSQ scores. Change in MHD was associated with improvements in MSQ and reductions in HIT‐6 scores, indicating the clinical importance of these changes in relation to PROs that measure function.  相似文献   
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Percutaneous transluminal coronary angioplasty is an accepted treatment for selected patients with single vessel disease but has not been rigorously evaluated in patients with double vessel disease. Among 769 patients undergoing transluminal coronary angioplasty between 1980 and 1984, 74 with double vessel stenosis of 50% or more underwent double vessel coronary angioplasty. Primary success was obtained for both lesions in 63 patients (85%), for one lesion in 11 patients (15%) and for 137 (93%) of 148 segments overall. Except for myocardial infarction in one patient, no serious complication occurred. Before coronary angioplasty, 15 patients had unstable angina, 14 had Canadian Cardiovascular Society class III and 32 class I to II effort angina and only 2 were asymptomatic. Six months after coronary angioplasty, 27 were asymptomatic, 27 had class I to II and 5 had class III effort angina and 2 had sustained an episode of unstable angina. During the follow-up study, two patients had an infarction and one had coronary artery bypass surgery. Coronary arteriography was performed at a mean of 5.5 +/- 2.1 months after coronary angioplasty in all but three patients. Restenosis was found in 30 (23%) of 132 segments with angiographic control. Restenosis was present in one vessel in 17 patients and in both vessels in 4; 40 patients (66%) had no restenosis. Of the 34 patients with definite or probable angina, 50% had restenosis and 19% of patients with restenosis were symptom free.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.

Background

Patient portals provide patients with the tools to better manage and understand their health status. However, widespread adoption of patient portals faces resistance from patients and providers for a number of reasons, and there is limited evidence evaluating the characteristics of patient portals that received positive remarks from patients and providers.

Objective

The objectives of this systematic review are to identify the shared characteristics of portals that receive favorable responses from patients and providers and to identify the elements that patients and providers believe need improvement.

Methods

The authors conducted a systematic search of the CINAHL and PubMed databases to gather data about the use of patient portals in the management of chronic disease. Two reviewers analyzed the articles collected in the search process in order remove irrelevant articles. The authors selected 27 articles to use in the literature review.

Results

Results of this systematic review conclude that patient portals show significant improvements in patient self-management of chronic disease and improve the quality of care provided by providers. The most prevalent positive attribute was patient-provider communication, which appeared in 10 of 27 articles (37%). This was noted by both patients and providers. The most prevalent negative perceptions are security (concerns) and user-friendliness, both of which occurred in 11 of 27 articles (41%). The user-friendliness quality was a concern for patients and providers who are not familiar with advanced technology and therefore find it difficult to navigate the patient portal. The high cost of installation and maintenance of a portal system, not surprisingly, deters some providers from implementing such technology into their practice, but this was only mentioned in 3 of the 27 articles (11%). It is possible that the incentives for meaningful use assuage the barrier of cost.

Conclusions

This systematic review revealed mixed attitudes from patients and their providers regarding the use of patient portals to manage their chronic disease. The authors suggest that a standard patient portal design providing patients with the resources to understand and manage their chronic conditions will promote the adoption of patient portals in health care organizations.  相似文献   
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