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961.
962.
AIMS: To examine the efficacy and safety of coadministered ezetimibe (EZE) with fenofibrate (FENO) in patients with mixed hyperlipidaemia. METHODS AND RESULTS: This was a multicentre, randomized, double-blind, placebo-controlled, parallel arm trial in patients with mixed hyperlipidaemia [LDL-cholesterol (LDL-C), 3.4-5.7 mmol/L (2.6-4.7 mmol/L for patients with type 2 diabetes); triglycerides (TG), 2.3-5.7 mmol/L] and no history of coronary heart disease (CHD), CHD-equivalent disease (except for type 2 diabetes), or CHD risk score>20%. A total of 625 patients was randomized in a 1:3:3:3 ratio to one of four daily treatments for 12 weeks: placebo; EZE 10 mg; FENO 160 mg; FENO 160 mg plus EZE 10 mg (FENO+EZE). The primary endpoint compared the LDL-C lowering efficacy of FENO+EZE vs. FENO alone. LDL-C, non-HDL-cholesterol (non-HDL-C), and apolipoprotein B were significantly (P<0.001) reduced with FENO+EZE when compared with FENO or EZE alone. TG levels were significantly decreased and HDL-C was significantly increased with FENO+EZE and FENO treatments when compared with placebo (P<0.001). Coadministration therapy reduced LDL-C by 20.4%, non-HDL-C by 30.4%, TG by 44.0%, and increased HDL-C by 19.0%. At baseline, >70% of all patients exhibited the small, dense LDL pattern B profile. A greater proportion of patients on FENO+EZE and FENO alone treatments shifted from a more atherogenic LDL size pattern to a larger, more buoyant, and less atherogenic LDL size pattern at study endpoint than those on placebo or EZE. All three active therapies were well tolerated. CONCLUSION: Coadministration of EZE with FENO provided a complementary efficacy therapy that improves the atherogenic lipid profile of patients with mixed hyperlipidaemia.  相似文献   
963.
BACKGROUND: We investigated the impact that micronutrient supplementation has on the progression of simian acquired immunodeficiency syndrome (SAIDS). METHODS: Twenty-four simian immunodeficiency virus-infected juvenile male rhesus macaques were randomized into 2 groups. One group was given certified chow, and the other group was given chow and a supplement that contained 2-3 times the estimated nutritional requirement of micronutrients. Virological, immunological, and body composition measurements were taken every 4 weeks for 120 weeks. RESULTS: There was no difference between groups in weight gain, body mass index (BMI), crown-heel length, waist circumference, total tissue mass, lean mass, bone mineral content, or bone mineral density. The rhesus macaques on the supplemented diet had a higher death rate (hazard ratio, 2.39; P<.001) than those on the nonsupplemented diet; death in both groups was associated with a higher viral load set point during the early phase of infection. Additionally, higher body weight, BMI, crown-rump length, and lower viral load set point were protective from death in both groups. CONCLUSIONS: Micronutrient supplementation did not significantly alter the progression of SAIDS with respect to changes in body composition and immunological characteristics. A significantly higher rate of death was observed in rhesus macaques on the supplemented diet.  相似文献   
964.
Risk factors for post-ERCP pancreatitis: a prospective, multicenter study   总被引:41,自引:0,他引:41  
BACKGROUND: Post-ERCP pancreatitis is poorly understood. The goal of this study was to comprehensively evaluate potential procedure- and patient-related risk factors for post-ERCP pancreatitis over a wide spectrum of centers. METHODS: Consecutive ERCP procedures were prospectively studied at 11 centers (6 private, 5 university). Complications were assessed at 30 days by using established consensus criteria. RESULTS: Pancreatitis occurred after 131 (6.7%) of 1963 consecutive ERCP procedures (mild 70, moderate 55, severe 6). By univariate analysis, 23 of 32 investigated variables were significant. Multivariate risk factors with adjusted odds ratios (OR) were prior ERCP-induced pancreatitis (OR 5.4), suspected sphincter of Oddi dysfunction (OR 2.6), female gender (OR 2.5), normal serum bilirubin (OR 1.9), absence of chronic pancreatitis (OR 1.9), biliary sphincter balloon dilation (OR 4.5), difficult cannulation (OR 3.4), pancreatic sphincterotomy (OR 3.1), and 1 or more injections of contrast into the pancreatic duct (OR 2.7). Small bile duct diameter, sphincter of Oddi manometry, biliary sphincterotomy, and lower ERCP case volume were not multivariate risk factors for pancreatitis, although endoscopists performing on average more than 2 ERCPs per week had significantly greater success at bile duct cannulation (96.5% versus 91.5%, p = 0.0001). Combinations of patient characteristics including female gender, normal serum bilirubin, recurrent abdominal pain, and previous post-ERCP pancreatitis placed patients at increasingly higher risk of pancreatitis, regardless of whether ERCP was diagnostic, manometric, or therapeutic. CONCLUSIONS: Patient-related factors are as important as procedure-related factors in determining risk for post-ERCP pancreatitis. These data emphasize the importance of careful patient selection as well as choice of technique in the avoidance of post-ERCP pancreatitis.  相似文献   
965.
BackgroundEstablishing medication effectiveness outside of a randomized trial requires careful study design to mitigate selection bias. Previous observational studies of β-blockers in patients with chronic kidney disease and heart failure have had methodologic limitations that may have introduced bias. We examined whether initiation of β-blocker therapy was associated with better outcomes among patients with chronic kidney disease and newly diagnosed heart failure with left ventricular systolic dysfunction.Methods and ResultsWe identified 668 adults in the Kaiser Permanente Northern California system from 2006 to 2008 with chronic kidney disease, incident heart failure, left ventricular systolic dysfunction, and no previous β-blocker use. We defined chronic kidney disease as estimated glomerular filtration rate <60 mL min?1 1.73 m?2 or proteinuria, and we excluded patients receiving dialysis. We used extended Cox regression to assess the association of treatment with death and the combined end point of death or heart failure hospitalization. Initiation of β-blocker therapy was associated with a significantly lower crude risk of death (hazard ratio [HR] 0.47, 95% confidence interval [CI] 0.35–0.63), but this association was attenuated and no longer significant after multivariable adjustment (HR 0.75, CI 0.51–1.12). β-Blocker therapy was significantly associated with a lower risk of death or heart failure hospitalization even after adjustment for potential confounders (HR 0.67, CI 0.51–0.88).Conclusionsβ-Blocker therapy is associated with lower risk of death or heart failure hospitalization among patients with chronic kidney disease, incident heart failure, and left ventricular systolic dysfunction.  相似文献   
966.
Water and its influence on plants likely exerted strong adaptive pressures in human evolution. Understanding relationships among water, plants, and early humans is limited both by incomplete terrestrial records of environmental change and by indirect proxy data for water availability. Here we present a continuous record of stable hydrogen-isotope compositions (expressed as δD values) for lipid biomarkers preserved in lake sediments from an early Pleistocene archaeological site in eastern Africa—Olduvai Gorge. We convert sedimentary leaf- and algal-lipid δD values into estimates for ancient source-water δD values by accounting for biochemical, physiological, and environmental influences on isotopic fractionation via published water–lipid enrichment factors for living plants, algae, and recent sediments. Reconstructed precipitation and lake-water δD values, respectively, are consistent with modern isotopic hydrology and reveal that dramatic fluctuations in water availability accompanied ecosystem changes. Drier conditions, indicated by less negative δD values, occur in association with stable carbon-isotopic evidence for open, C4-dominated grassland ecosystems. Wetter conditions, indicated by lower δD values, are associated with expanded woody cover across the ancient landscape. Estimates for ancient precipitation amounts, based on reconstructed precipitation δD values, range between approximately 250 and 700 mm·y−1 and are consistent with modern precipitation data for eastern Africa. We conclude that freshwater availability exerted a substantial influence on eastern African ecosystems and, by extension, was central to early human proliferation during periods of rapid climate change.  相似文献   
967.
Photofrin® was first approved in the 1990s as a sensitizer for use in treating cancer via photodynamic therapy (PDT). Since then a wide variety of dye sensitizers have been developed and a few have been approved for PDT treatment of skin and organ cancers and skin diseases such as acne vulgaris. Porphyrinoid derivatives and precursors have been the most successful in producing requisite singlet oxygen, with Photofrin® still remaining the most efficient sensitizer (quantum yield = 0.89) and having broad food and drug administration (FDA) approval for treatment of multiple cancer types. Other porphyrinoid compounds that have received approval from US FDA and regulatory authorities in other countries include benzoporphyrin derivative monoacid ring A (BPD-MA), meta-tetra(hydroxyphenyl)chlorin (m-THPC), N-aspartyl chlorin e6 (NPe6), and precursors to endogenous protoporphyrin IX (PpIX): 1,5-aminolevulinic acid (ALA), methyl aminolevulinate (MAL), hexaminolevulinate (HAL). Although no non-porphyrin sensitizer has been approved for PDT applications, a small number of anthraquinone, phenothiazine, xanthene, cyanine, and curcuminoid sensitizers are under consideration and some are being evaluated in clinical trials. This review focuses on the nature of PDT, dye sensitizers that have been approved for use in PDT, and compounds that have entered or completed clinical trials as PDT sensitizers.  相似文献   
968.
AIM: To survey gastroenterologists and hepatologists regarding their current views on treating hepatitis C virus (HCV) infected alcoholic hepatitis (AH) patients. METHODS: A sixteen item questionnaire was electronically mailed to gastroenterologists and hepatologists. A reminder was sent after 2 mo to increase the response rate. Participation of respondents was confidential. Accessing secured web site to respond to the questionnaire was considered as informed consent. Responses received on the secured website were downloaded in an excel sheet for data analysis. RESULTS: Analyzing 416 responses to 1556 (27% response rate) emails, 57% respondents (56% gastroenterologists) reported HCV prevalence > 20% amongst AH patients. Sixty nine percent often treated AH and 46% preferred corticosteroids (CS). Proportion of respondents with consensus (75% or more respondents agreeing on question) on specific management of HCV infected AH were: routine HCV testing (94%), HCV not changing response to CS (80%) or pentoxifylline (91%), no change in approach to treating HCV infected AH (75%). None of respondent variables: age, specialty, annual number of patients seen, and HCV prevalence could predict respondent to be in consensus on any of or all 4 questions. Further, only 4% would choose CS for treating HCV infected AH as opposed to 47% while treating HCV negative AH. CONCLUSION: Gastroenterologists and hepatologists believe that AH patients be routinely checked for HCV. However, there is lack of consensus on choice of drug for treatment and outcome of HCV positive AH patients. Studies are needed to develop guidelines for management of HCV infected AH patients.  相似文献   
969.
Evidence has now accumulated that colonoscopy and removal of polyps,especially during screening and surveillance programs,is effective in overall risk reduction for colon cancer.After resection of malignant pedunculated colon polyps or early stage colon cancers,long-term repeated surveillance programs can also lead to detection and removal of asymptomatic high risk advanced adenomas and new early stage metachronous cancers.Early stage colon cancer can be defined as disease that appears to have been completely resected with no subsequent evidence of involvement of adjacent organs,lymph nodes or distant sites.This differs from the clinical setting of an apparent"curative"resection later pathologically upstaged following detection of malignant cells extending into adjacent organs,peritoneum,lymph nodes or other distant sites,including liver.This highly selected early stage colon cancer group remains at high risk for subsequent colon polyps and metachronous colon cancer.Precise staging is important,not only for assessing the need for adjuvant chemotherapy,but also for patient selection for continued surveillance.With advanced stages of colon cancer and a more guarded outlook,repeated surveillance should be limited.In future,novel imaging technologies(e.g.,confocal endomicroscopy),coupled with increased pathological recognition of high risk markers for lymph node involvement(e.g.,"tumor budding")should lead to improved staging and clinical care.  相似文献   
970.
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