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91.
白介素与溃疡性结肠炎   总被引:17,自引:1,他引:17  
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关.  相似文献   
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CONTEXT: Bone density measurement with dual-energy x-ray absorptiometry is widely used for fracture risk assessment. It has not been established that published gradients of fracture risk from study populations can be directly applied to clinical populations. OBJECTIVE: The objective of the study was to assess osteoporotic fracture prediction with dual-energy x-ray absorptiometry in a large clinical cohort. DESIGN: This was a historical cohort study (mean observation period 3.2 +/- 1.5 yr). PATIENTS: The study population was drawn from the population-based database of the Manitoba Bone Density Program. Analyses were limited to women aged 50 yr or older at baseline (n = 16,505). MAIN OUTCOME MEASURE: Each subject's longitudinal health service record was assessed for the presence of nontrauma fracture codes (hip, spine, wrist, and humerus) after bone density testing. Age-adjusted hazard ratios for fracture were derived from Cox proportional hazards models. RESULTS: Site-specific and overall fracture rates were significantly associated with each site of bone density measurement (all P < 0.00001). The 95% confidence intervals overlapped those from a widely cited metaanalysis of fracture prediction from different sites. Although fracture prediction was not significantly different between the three hip measurement sites, each hip site was better than the lumbar spine for predicting overall fractures (nonoverlapping 95% confidence intervals). The manufacturer sd (equivalent to a unit change in T-score) resulted in a significantly smaller gradient of risk for the spine than when the population sd was used. CONCLUSIONS: Bone density measurements are effective for predicting fractures in clinical practice. However, hip measurements were superior to the spine in overall osteoporotic fracture prediction.  相似文献   
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Walsh NE, Brooks P, Hazes JM, Walsh RM, Dreinhöfer K, Woolf AD, Åkesson K, Lidgren L, for the Bone and Joint Decade Task Force for Standards of Care for Acute and Chronic Musculoskeletal Pain. Standards of care for acute and chronic musculoskeletal pain: the Bone and Joint Decade (2000−2010).Musculoskeletal conditions often manifest with the onset of pain and the resulting physical limitations. Musculoskeletal pain is almost inevitable in an individual's lifetime. It is one of the most common reasons for self-medication and entry into the health care system. Musculoskeletal pain affects 1 in 4 adults and is the most common source of serious long-term pain and physical disability. The monumental impact of musculoskeletal conditions is now recognized by the United Nations, the World Health Organization, World Bank, and numerous governments throughout the world through support of the Bone and Joint Decade 2000 to 2010 initiative. Individuals with musculoskeletal pain concerns are regularly ignored, their complaints often misunderstood by health care providers, and accordingly they do not receive timely or effective treatment. The standards of care in this document are designed to provide generic guidelines for appropriate care of people with acute or chronic musculoskeletal pain. This document was developed over a 4-year period using multiple international meetings and a Task Force of the Bone and Joint Decade for developing international standards for the care of acute and chronic musculoskeletal pain. The final document is a product of the World Health Organization Collaborating Centre for Evidence-Based Health Care in Musculoskeletal Disorders.  相似文献   
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BACKGROUND: Gastrointestinal (GI) symptoms and high dosing frequency have been cited as reasons for inadequate adherence to daily or weekly oral bisphosphonate therapy. Inadequate adherence may lead to poor therapeutic outcomes. OBJECTIVE: The PRIOR study evaluated adherence to and GI tolerability of monthly therapy with oral and quarterly intravenous ibandronate in postmenopausal women with osteoporosis or osteopenia. METHODS: This 12-month, multicenter, prospective, nonrandomized, open-label, noninferiority study included postmenopausal women with osteoporosis or osteopenia who had discontinued previous daily or weekly oral bisphosphonate therapy because of GI intolerance. Participants chose to receive either monthly oral ibandronate 150 mg or quarterly intravenous ibandronate 3 mg and were permitted to switch formulations once during the study. For oral treatment, adherence was assessed based on doses taken, as recorded on the case-report form; for intravenous treatment, adherence was assessed based on doses administered, as recorded by study site personnel. Participants who took >or=75% of protocol-specified doses were considered adherent. The rate of adherence to oral ibandronate was protocol defined as noninferior to that of intravenous ibandronate if the upper limit of the 2-sided 90% CI for the adjusted difference in adherence rates was >20%. At screening, participants assessed the tolerability of their previous bisphosphonate therapy using the GI Experience Survey; using the same instrument, they assessed the tolerability of ibandronate 1 month from baseline and at months 4, 7, and 10. RESULTS: Of 543 participants in the intent-to-treat population, 147 (27.1%) chose to receive oral treatment and 396 (72.9%) chose to receive intravenous treatment. The mean age of participants was approximately 66 years in both groups, and >90% of participants were white. A significantly greater proportion of participants who selected intravenous versus oral treatment had a primary diagnosis of osteoporosis (72.2% vs 57.1%, respectively; P<0.001) and a history of fracture as an adult (35.6% vs 22.4%; P >or= 0.004); significantly fewer recipients of intravenous versus oral ibandronate were currently working (29.0% vs 39.5%; P >or= 0.021). Overall, 82.9% of participants had previously received alendronate and 44.9% had previously received risedronate. Eleven participants switched from oral to intravenous therapy and 16 switched from intravenous to oral therapy during the study. In the perprotocol population, 69.7% of participants in the oral group (101/145) and 82.9% of participants in the intravenous group (325/392) were adherent to their originally selected therapy. Adherence to oral therapy fell within the prespecified boundary for noninferiority to intravenous therapy (adjusted difference: 12.4%; 90% CI, 5.1-19.7). Mean GI tolerance scores were significantly improved from screening at all subsequent assessment times in both treatment groups (P < 0.001); >75% of participants had a >or=10% increase in GI tolerability scores from screening. Both dosing regimens were generally well tolerated. CONCLUSION: Self-selected monthly oral or quarterly intravenous ibandronate therapy was associated with high adherence rates among these postmenopausal women with osteoporosis or osteopenia who had previously discontinued oral bisphosphonate treatment because of GI intolerance.  相似文献   
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