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991.
OBJECTIVE: In response to health concerns of military members about deployment and other service-related exposures, the Department of Defense (DoD) initiated the largest prospective study ever undertaken in the U.S. military. STUDY DESIGN AND SETTING: The Millennium Cohort uses a phased enrollment strategy to eventually include more than 100,000 U.S. service members who will be followed up through the year 2022, even after leaving military service. Subjects will be linked to DoD and Veterans Affairs databases and surveyed every 3 years to obtain objective and self-reported data on exposures and health outcomes. RESULTS: The first enrollment phase was completed in July 2003 and resulted in 77,047 consenting participants, well representative of both active-duty and Reserve/Guard forces. This report documents the baseline characteristics of these Cohort members, describes traditional, postal, and Web-based enrollment methods; and describes the unique challenges of enrolling, retaining, and following such a large Cohort. CONCLUSION: The Millennium Cohort was successfully launched and is becoming especially relevant, given current deployment and exposure concerns. The Cohort is representative of the U.S. military and promises to provide new insight into the long-term effects of military occupations on health for years to come.  相似文献   
992.
993.
OBJECTIVE: WHO's new Global Plan to Stop TB 2006-2015 advises countries with a high burden of tuberculosis (TB) to expand case-finding in the private sector as well as services for patients with HIV and multidrug-resistant TB (MDR-TB). The objective of this study was to evaluate these strategies in Thailand using data from the Thailand TB Active Surveillance Network, a demonstration project begun in 2004. METHODS: In October 2004, we began contacting public and private health-care facilities monthly to record data about people diagnosed with TB, assist with patient care, provide HIV counselling and testing, and obtain sputum samples for culture and susceptibility testing. The catchment area included 3.6 million people in four provinces. We compared results from October 2004-September 2005 (referred to as 2005) to baseline data from October 2002-September 2003 (referred to as 2003). FINDINGS: In 2005, we ascertained 5841 TB cases (164/100 000), including 2320 new smear-positive cases (65/100 000). Compared with routine passive surveillance in 2003, active surveillance increased reporting of all TB cases by 19% and of new smear-positive cases by 13%. Private facilities diagnosed 634 (11%) of all TB cases. In 2005, 1392 (24%) cases were known to be HIV positive. The proportion of cases with an unknown HIV status decreased from 66% (3226/4904) in 2003 to 23% (1329/5841) in 2005 (P< 0.01). Of 4656 pulmonary cases, mycobacterial culture was performed in 3024 (65%) and MDR-TB diagnosed in 60 (1%). CONCLUSION: In Thailand, piloting the new WHO strategy increased case-finding and collaboration with the private sector, and improved HIV services for TB patients and the diagnosis of MDR-TB. Further analysis of treatment outcomes and costs is needed to assess this programme's impact and cost effectiveness.  相似文献   
994.
Canada has a long tradition of leading practice-changing clinical trials in oncology. Here, we describe methodology, results, and interpretation of oncology RCTs with Canadian involvement compared to RCTs from other high-income countries (HICs). A literature search identified all RCTs evaluating anti-cancer therapies published 2014–2017. RCTs were classified based on the country affiliation of first authors. The study cohort included 636 HIC-led RCTs; 155 (24%) had Canadian authors. Three-quarters (112/155, 72%) of Canadian RCTs were conducted in the palliative setting, compared to two thirds (299/481, 62%) of RCTs from other HICs (p = 0.022). Canadian RCTs were more likely than those from other HICs to be supported by industry (85% vs. 69%, p < 0.001). The proportion of positive Canadian trials that met the ESMO-MCBS threshold for substantial clinical benefit was comparable to RCTs without Canadian authors (29% vs. 32%, p = 0.137). Thirteen percent (20/155) of all Canadian trials were affiliated with the Canadian Cancer Trials Group (CCTG). Canada plays a meaningful role in the global cancer research ecosystem but is overly reliant on industry support. The very low proportion of trials that identify a new treatment with substantial clinical benefit is worrisome. A renewed investment in cancer clinical trials is needed in Canada.  相似文献   
995.
This study utilizes data from clinical reports of 1441 youth and adults in the USA to examine the types of problematic Internet experiences mental health professionals report as clients' primary or secondary presenting problems. Overall, clients who present in treatment with an Internet problem are more likely to have problems related to overuse of the Internet; use of adult pornography; use of child pornography; sexual exploitation perpetration; and gaming, gambling, or role-playing. Other Internet-related problems, such as isolative-avoidant use, sexual exploitation victimization, harassment perpetration, and online infidelity were equally likely to present in treatment as a primary problem or secondary to other mental health concerns. Some differences between youth and adult clients were also identified. Findings suggest some initial support for the importance of including Internet use, experiences, and behavior as part of an initial clinical assessment.  相似文献   
996.
997.
Professional practice programs are designed to attract, retain, and reward nurses. This three-part series will describe Vanderbilt's performance-based career advancement system, the Vanderbilt Professional Nursing Practice Program (VPNPP). Part 1 outlines the overall program's foundation, philosophical background, and basic structure. The VPNPP is built upon Benner's work, distinguishing among four levels of practice: novice, competent, proficient, and expert. Work by many in the organization identified the expected behaviors for nurses at each level, which were then used to develop clear process evaluation criteria. Part 2 will examine the performance measurement and evaluation system created to support the program. The process of advancing within the program will be described in part 3.  相似文献   
998.
OBJECTIVES: To define the minimum clinically important difference (MCID) for the visual analog scale (VAS) of pain severity by measuring the change in VAS associated with adequate pain control. METHODS: The authors conducted a prospective, observational study. Adult emergency department (ED) patients with acute pain (<72 hours) were eligible. Patients rated their pain severity on a 100-mm VAS on presentation and at discharge. Patients were asked if they would accept any analgesic, then if they would accept a parenteral analgesic before treatment. At discharge, they were asked whether they had received adequate pain control. RESULTS: The authors enrolled 143 patients (mean age, 36 years; 54% female). The mean decrease in VAS was -30.0 mm (95% confidence interval [CI] = -36.4 to -23.6) for the 116 of 143 (81%) patients with adequate pain control at discharge vs. -5.7 (95% CI = -11.2 to -0.3) for the 27 with inadequate pain control (p < 0.001). At discharge, the mean VAS was 31.3 mm for those with adequate pain control vs. 55.1 for those without. Mean VAS for the 114 of 143 patients who would accept any analgesics initially was 64.7 vs. 47.1 for the 29 reporting no analgesic need. Initially, 77 patients would accept parenteral analgesics (mean VAS = 72.5 mm). CONCLUSIONS: A mean reduction in VAS of 30.0 mm represents a clinically important difference in pain severity that corresponds to patients' perception of adequate pain control. Defining MCID based on adequate analgesic control rather than minimal detectable change may be more appropriate for future analgesic trials, when effective treatments for acute pain exist.  相似文献   
999.
The dependence of vascular relaxation on an intact endothelium and the relationship between relaxation and cyclic GMP accumulation were determined in coronary arteries isolated from cardiac transplantation patients with or without coronary atherosclerosis. In nonatherosclerotic arteries, the endothelium-dependent agent acetylcholine produced concentration-related relaxations. In atherosclerotic arteries, endothelium-dependent relaxations were abolished with acetylcholine, partly suppressed with substance P and histamine, and completely preserved with the ionophore A23187. In these arteries, the endothelium-independent agent nitroglycerin remained fully active. Accumulation of cyclic GMP in atherosclerotic strips was suppressed with acetylcholine but unattenuated with A23187 and nitroglycerin. In aortas from rabbits with diet-induced atherosclerosis, there was likewise an impaired cholinergic relaxation and cyclic GMP accumulation in the presence of preserved responses to A23187 and nitroglycerin. The results demonstrate that impaired cholinergic responses in atherosclerotic arteries reflect a muscarinic defect and not an inability of endothelium to release endothelial factor or smooth muscle to respond to it.  相似文献   
1000.
In patients with congestive heart failure (CHF), the poor relationship between systemic exercise performance and cardiac function, together with morphologic and metabolic abnormalities in skeletal muscle, raises the possibility that skeletal muscle function may be impaired and limit systemic exercise performance. We assessed strength and endurance of the knee extensors during static and dynamic exercise in 16 patients with Class I-IV CHF and eight age-matched sedentary controls and related these measurements to systemic exercise performance. To assess skeletal muscle function independent of peripheral blood flow, endurance was repeated under ischemic conditions. Strength was not significantly different in the two groups. Dynamic endurance, quantified as the decline in peak torque during 15 successive isokinetic knee extensions, was significantly reduced in the patients compared to controls during aerobic (peak torque 65 vs. 86% of initial for exercise at 90 deg/s and 60 vs. 85% for exercise at 180 deg/s; P less than 0.002 for both), and during ischemic exercise (56 vs. 76% of initial torque; P less than 0.01). Static endurance, defined as the time required for force during a sustained maximal voluntary contraction to decline to 60% of maximal, was reduced in the patients compared to controls (40 +/- 14 vs. 77 +/- 29 s; P less than 0.02). There were highly significant relationships between systemic exercise performance and skeletal muscle endurance at 90 and 180 deg/s in the patients with CHF (r = 0.90 and 0.66, respectively). These findings indicate that skeletal muscle endurance is impaired in patients with CHF, that this abnormality is in part independent of limb blood flow, and that these changes may be important determinants of systemic exercise performance.  相似文献   
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