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51.
OBJECTIVE: To examine the association of elderly onset rheumatoid arthritis (RA) with health related quality of life in a population based cohort of older women. METHODS: A nested case-control study of elderly onset RA within the Iowa Women's Health Study (IWHS), a prospective cohort established in 1986 of 41,000 women aged 55 to 69 years. A supplemental questionnaire was mailed to 122 RA cases and 1132 frequency matched controls from the cohort. We used unconditional logistic regression and linear regression to examine the association of elderly onset RA with self-reported measures of functional disability and quality of life. RESULTS: Elderly onset RA was associated with a 6-fold risk (OR 6.0, 95% CI 3.6-10.1) of significant functional disability (Health Assessment Questionnaire score (3) 1). Similarly, elderly onset RA was significantly associated with lower physical component scores of the Medical Outcome Study Short Form-12 (37.2 +/- 10.9 vs 43.6 +/- 11.6; p < 0.001). CONCLUSION: Among a community based cohort, elderly onset RA was strongly associated with functional disability and reduced quality of life. These associations were independent of other age associated factors including depression, recent fracture, and multiple comorbidities.  相似文献   
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OBJECTIVE: Vitamin D is a potent regulator of calcium homeostasis and may have immunomodulatory effects. The influence of vitamin D on human autoimmune disease has not been well defined. The purpose of this study was to evaluate the association of dietary and supplemental vitamin D intake with rheumatoid arthritis (RA) incidence. METHODS: We analyzed data from a prospective cohort study of 29,368 women of ages 55-69 years without a history of RA at study baseline in 1986. Diet was ascertained using a self-administered, 127-item validated food frequency questionnaire that included supplemental vitamin D use. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards regression, adjusting for potential confounders. RESULTS: Through 11 years of followup, 152 cases of RA were validated against medical records. Greater intake (highest versus lowest tertile) of vitamin D was inversely associated with risk of RA (RR 0.67, 95% CI 0.44-1.00, P for trend = 0.05). Inverse associations were apparent for both dietary (RR 0.72, 95% CI 0.46-1.14, P for trend = 0.16) and supplemental (RR 0.66, 95% CI 0.43-1.00, P for trend = 0.03) vitamin D. No individual food item high in vitamin D content and/or calcium was strongly associated with RA risk, but a composite measure of milk products was suggestive of an inverse association with risk of RA (RR 0.66, 95% CI 0.42-1.01, P for trend = 0.06). CONCLUSION: Greater intake of vitamin D may be associated with a lower risk of RA in older women, although this finding is hypothesis generating.  相似文献   
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A new variant of congenital hemolyticanemia associated with stomatocytosis,reticulocytosis, decreased osmotic fragility, type I autohemolysis and shortened erythrocyte survival without specific splenic sequestration was discoveredin three siblings of Swiss-German ancestry. Increased intracellular sodium(two to three times normal) and slightlydecreased intracellular potassium weredetected. Total sodium efflux was eight-fold greater than normal but total potassium influx was normal and ouabain-sensitive potassium influx was decreased.The ouabain-sensitive sodium efflux:potassium influx ratio was 26:1 ratherthan the 3:2 ratio noted in normal cells.The consanguineous parents, four othersiblings, and 44 other family membershad mild stomatocytosis, reticulocytosis,and, when studied, decreased osmoticfragility, increased autohemolysis, intermediate abnormalities of cation content,cation flux, and moderate shortening oferythrocyte survival. Autosomal dominant inheritance was suggested. Noabnormalities of RBC enzymes, hemoglobin or lipids were observed. No abnormalities of membrane protein weredetected on acrylamide gel. Substratedepletion of these hypermetabolic cellsresulted in intracellular dehydrationwith potassium loss in excess of sodiumgain and decreased deformability. Although the exact nature of the defectresponsible for hemolysis is unknown,this syndrome differs from other hereditary hemolytic anemias associated withstomatocytosis.

Submitted on December 21, 1970 Revised on March 16, 1971 Accepted on March 29, 1971  相似文献   
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Platelet glycoproteins IIb and IIIa as a calcium channel in liposomes   总被引:3,自引:0,他引:3  
Rybak  ME; Renzulli  LA; Bruns  MJ; Cahaly  DP 《Blood》1988,72(2):714-720
Human platelet membrane glycoproteins IIb and IIIa (GPIIb and IIIa) were incorporated into phospholipid vesicles by the reverse-phase technique to assess the ability of GPIIb and IIIa to function as a Ca2+ channel. Movement of Ca2+ across the lipid bilayer was quantitated by injection of proteoliposomes with encapsulated Fura-2 into Ca2+ buffers and measurement of Fura-2 fluorescence as an indicator of Ca2+ influx. Reciprocally, to assess the function of proteins in an inside-out orientation, Ca2+-loaded vesicles were injected into Ca2+-free buffer and Ca2+ efflux monitored by a calcium electrode. Incorporation of the IIb-IIIa complex produced significant facilitation of Ca2+ movement across the lipid bilayer. No net transmembrane Ca2+ movement was seen with dissociated IIb and IIIa. Movement of Ca2+ was proportional to the transmembrane Ca2+ gradient. Ca2+ movement into the vesicles was inversely proportional to extravesicular NaCl from 25 to 150 mmol/L, analogous to several studies in the intact platelet. Adenosine triphosphate had no effect on Ca2+ movement into or out of the vesicles. Specific inhibition of a Ca2+ shift into the vesicles was seen with M148, a monoclonal antibody to IIb/IIIa, while no inhibition was observed with a panel of other anti-IIb/IIIa monoclonal antibodies. This suggests that a specific site on the complex or orientation of the complex is essential for calcium channel function. These data demonstrate that the GPIIb/IIIa complex can serve as a passive Ca2+ channel across a phospholipid bilayer and has the potential to play a role in Ca2+ flux across the platelet plasma membrane.  相似文献   
58.
目的 对比分析单纯后路内固定+一期经腰椎间孔病椎间病灶清除(TLIF)与经典的前后联合手术在布氏杆菌性脊柱炎患者中的临床疗效及安全性。 方法 对我院2015年1月至2017年12月收治的93例布病性脊柱炎患者的临床资料进行分析。按手术方式分为观察组(45例)和对照组(48例)。对两组患者的基础数据、临床指标、术前术后各项指标水平以及术后并发症、植骨治愈情况。 结果 观察组与对照组基础数据比较,差异无统计学意义(P>0.05)。观察组患者的手术时间、住院天数、术中出血量及术后下床时间均明显低于对照组(P<0.01)。两组患者术后3个月的ODI、VAS、CRP、ESR及Cobb角均明显低于术前(P<0.05);术后3个月,观察组患者的ODI、VAS、CRP、ESR及Cobb角均明显低于对照组(P<0.05)。观察组术后并发症发生率(4.4%)明显低于对照组(25.0%)(Χ2=7.674,P<0.01)。 结论 TLIF治疗布氏杆菌性脊柱炎患者的临床疗效突出,安全性较好,更有利于患者术后身体的恢复。  相似文献   
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Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material.  相似文献   
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