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991.
Obesity has reached epidemic proportions in many countries and is an established risk factor in many chronic illnesses, but its role in acute illness is less clear. Pancreatologists have long recognized obesity as a risk factor for a poor outcome in severe acute pancreatitis. There are now several studies that have identified obesity as a primary risk factor for developing local complications (abscess, pseudocyst, necrosis), organ failure, and death. Indeed, meta-analysis of these studies gives a relative risk of 4.3 for local complications, 2.0 for systemic complications, and 2.1 for death. This has led to proposed modifications of acute pancreatitis scoring systems to include obesity as an independent primary predictive factor of severe disease. Obesity is associated with a low-grade inflammatory state, which may predispose obese patients to such complications. Furthermore, visceral obesity and visceral adipose tissue may be particularly important in underlying the pathophysiology of these observations.  相似文献   
992.
PURPOSE OF REVIEW: Overall survival remains the benchmark in phase III settings of novel agents in castration-resistant metastatic prostate cancer. This review highlights many of the current potential early measures of response and clinical benefit that are worthy of future study and validation in this disease. RECENT FINDINGS: The clinical evaluation of novel agents in advanced prostate cancer remains challenging for several reasons. Men with metastatic prostate cancer often have bone-only disease in which formal radiologic response and progression criteria may not apply. Declines in serum prostate-specific antigen levels may be modest surrogates of response to cytotoxic agents such as docetaxel, but have not been validated for agents with novel mechanisms of action, such as antiangiogenic, immunologic, or cytostatic drugs. Novel radiologic imaging techniques such as PET scans are not yet validated for use in monitoring or staging advanced prostate cancer. Measures of delay, control, and palliation of metastatic disease such as pain response, time to progression and progression-free survival, while appealing endpoints that may highlight the clinical benefit of novel agents, have been difficult to define rigorously and have not yet demonstrated adequate surrogacy for overall survival. SUMMARY: The measures of response highlighted in this review, if validated, may improve the current evaluation of novel agents in phase II settings and the potential accelerated approval of these agents.  相似文献   
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In 2007, drug development in castration-resistant metastatic prostate cancer (CRPC) remains challenging, due to the number of potentially viable molecular targets and clinical trials available, the lack of established surrogates for overall survival, and competing causes of mortality. This review will highlight the highest impact phase II and phase III trials of novel agents in the current CRPC landscape, and focus on both molecular targets and clinical trial designs that are more likely to demonstrate clinical benefit. The need for tissue correlative studies for target evaluation and drug mechanism is stressed to continue to advance the field and to define biomarkers that may identify patient populations that may derive a greater benefit from these molecular agents.  相似文献   
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997.
The vertebrate hosts of 672 blood-engorged Culex quinquefasciatus Say, collected in Harris County, Texas, during 2005, were identified by nucleotide sequencing PCR products of the cytochrome b gene. Analysis revealed that 39.1% had acquired blood from birds, 52.5% from mammals, and 8.3% were mixed avian and mammalian blood meals. Most frequent vertebrate hosts were dog (41.0%), mourning dove (18.3%), domestic cat (8.8%), white-winged dove (4.3%), house sparrow (3.2%), house finch (3.0%), gray catbird (3.0%), and American robin (2.5%). Results are interpreted in conjunction with concurrent avian and mosquito West Nile virus (WNV) surveillance activities in Harris County. We conclude that Cx. quinquefasciatus is an opportunistic feeder and principal mosquito vector of WNV in this metropolitan area; however, transmission by other mosquito species or by other modes of infection, such as ingestion, must account for the high WNV infection rates among local blue jays and American crows.  相似文献   
998.
BACKGROUND: The validated Blatchford risk score (BRS) predicts outcomes in patients with nonvariceal upper gastrointestinal tract bleeding, before endoscopy; completion of the Rockall score requires endoscopy. The aims of this study were to predict whether the modified BRS (mBRS) can predict (1) endoscopic high-risk stigmata (HRS) and (2) rebleeding and mortality. METHODS: Clinical and demographic characteristics on 1869 patients from 6 Canadian provinces were prospectively entered into the Registry for Upper GI Bleeding and Endoscopy database, recording 30-day rebleeding and mortality. The Rockall score and mBRS (hemoglobin level, hemodynamic instability, and presence of melena, liver disease, or cardiac failure; urea and syncope were not recorded) were calculated. Logistic regression was used to assess the association between an mBRS of 1 or less with HRS and with rebleeding and mortality. RESULTS: The mean (SD) age of the patients was 66 (17) years, with 62% men and a mean of 2.5 comorbidities. Of the 1860 patients with 30-day rebleeding data, 334 (18.0%) rebled; 5.3% died. The mBRS was 0 in 3% and 1 or less in 9.8% of patients; HRS were seen in 31.0% of patients. An mBRS of 1 or less was associated with lower rebleeding (5% vs 19%; P<.001) and mortality (0.5% vs 5.8%; P=.003), and was significant in multivariate analysis for rebleeding (odds ratio, 0.24; 95% confidence interval, 0.12-0.48) and mortality (odds ratio, 0.12; 95% confidence interval, 0.02-0.90). The HRS were less frequent when the mBRS was 1 or less (16.9% vs 32.7%; odds ratio, 0.4; 95% confidence interval, 0.3-0.6). Patients with a low mBRS with HRS had a low rebleeding rate (3.3%) and a lower apparent benefit from endoscopic therapy. CONCLUSIONS: An mBRS of 1 or less identifies approximately 10% of patients with gastrointestinal tract bleeding with a low likelihood of having HRS and a low risk of adverse outcomes. A prospective randomized study is required to examine whether this subgroup of patients presenting after hours could be discharged safely from emergency departments with arrangements for (urgent) outpatient endoscopy.  相似文献   
999.
OBJECTIVE: To compare short-term and long-term effectiveness of the Arthritis Self-Help Course (ASHC) and the Chronic Disease Self-Management Program (CDSMP) for persons with arthritis concerning health care use, health-related quality of life, health behaviors, and arthritis self-efficacy. METHODS: Forty-eight workshops were randomized to the ASHC (n = 26) or CDSMP (n = 22). A total of 416 individuals, including 365 African Americans, participated. The mean age for each group was 64 years, mean years of education was 11.7, mean number of chronic conditions was 4, and 75-80% of participants in each group were female. Multivariate statistical tests were used to assess effectiveness within and between programs for all workshop participants and African Americans. RESULTS: At 4 months all ASHC participants including African Americans, had significant improvements (P 相似文献   
1000.

Purpose

To assess the effects of socioeconomic status on mortality in patients with acute myocardial infarction.

Material and Methods

We studied a retrospective cohort of 5622 patients who presented to a hospital emergency department with an initial episode of acute myocardial infarction between April 1998 and March 2002 in the Province of Alberta, Canada. Our main outcome measure was 1-year all-cause mortality following the index emergency department visit; we used socioeconomic status (measured by neighborhood median household income) as our main predictor after controlling for patient and hospital characteristics and revascularization.

Results

Socioeconomic status profoundly affected the rate of emergency department presentation and the process and outcome of acute myocardial infarction care. In patients belonging to the lowest versus the highest socioeconomic status quartile, the risk of presenting to the emergency department was 72% higher (P <.001); at 1 year, revascularization was lower (36% vs 48%, P <.001), and mortality higher (19.1% vs 9.1%, P <.001). Socioeconomic status was independently associated with 1-year mortality after adjustment for baseline characteristics and 1-year revascularization, and socioeconomic status was especially influential in non-revascularized patients.

Conclusions

Given the influence of socioeconomic status on mortality after acute myocardial infarction and the key role of revascularization in modulating this relationship, our study has important implications for access to and process of cardiac care.  相似文献   
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