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91.
OBJECTIVE: This prospective study investigated the comparative responsiveness to change of 4 different elbow scoring instruments: 2 Hospital for Special Surgery elbow assessment scales, the Mayo Clinic Elbow Performance Index, and the Elbow Functional Assessment (EFA) Scale. METHODS: A group of patients with rheumatoid arthritis (RA) (median age 60 yrs) undergoing either elbow arthroplasty (22 elbows) or synovectomy with radial head excision (3 elbows) were evaluated both before and after surgery (median 7 mo postoperatively). Changes in the scores obtained using the scales under study were calculated and analyzed. The patient's opinion of global perceived effect of the intervention was used as an external criterion to classify them as "improved" or "non-changed." Responsiveness was evaluated with 3 different statistical approaches: using paired t statistics (pre and postsurgery scores), effect size statistics (standardized response mean, effect size, and responsiveness ratios), and receiver operator characteristic curves. Minimal clinically important difference was estimated using patient satisfaction as the external criterion. RESULTS: Each of the elbow rating measures under study proved to be responsive to change when evaluating patients with RA undergoing elbow arthroplasty or synovectomy. The EFA scale had the highest power to detect a clinically meaningful difference and had the best discriminative ability to distinguish improved from no-change patients, as shown by all responsiveness statistics applied. CONCLUSION: Using the EFA scale requires smaller sample sizes to achieve a fixed level of statistical power than the other scales we studied.  相似文献   
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During the last decades, the incidence of type 1 diabetes (T1D) has increased significantly, reaching percentages of 3% annually worldwide. This increase suggests that besides genetical factors environmental perturbations (including viral infections) are also involved in the pathogenesis of T1D. T1D has been associated with viral infections including enteroviruses, rubella, mumps, rotavirus, parvovirus and cytomegalovirus (CMV). Although correlations between clinical presentation with T1D and the occurrence of a viral infection that precedes the development of overt disease have been recognized, causalities between viruses and the diabetogenic process are still elusive and difficult to prove in humans. The use of experimental animal models is therefore indispensable, and indeed more insight in the mechanism by which viruses can modulate diabetogenesis has been provided by studies in rodent models for T1D such as the biobreeding (BB) rat, nonobese diabetic (NOD) mouse or specific transgenic mouse strains. Data from experimental animals as well as in vitro studies indicate that various viruses are clearly able to modulate the development of T1D via different mechanisms, including direct beta-cell lysis, bystander activation of autoreactive T cells, loss of regulatory T cells and molecular mimicry. Data obtained in rodents and in vitro systems have improved our insight in the possible role of viral infections in the pathogenesis of human T1D. Future studies will hopefully reveal which human viruses are causally involved in the induction of T1D and this knowledge may provide directions on how to deal with viral infections in diabetes-susceptible individuals in order to delay or even prevent the diabetogenic process.  相似文献   
95.
The functional outcome of shoulder replacement is related to the condition of the rotator cuff. Rotator cuff disease is a common problem in candidates for total shoulder arthroplasty; this study relates the functional status of the rotator cuff to the initial stability of a cementless glenoid implant. A 3D finite element model of a complete scapula was used to quantify the effect of a dysfunctional rotator cuff in terms of bone-implant interface micromotions when the implant is physiologically loaded shortly after surgery. Four rotator cuff conditions (from fully intact to progressively ruptured rotator cuff tendons) as well as two bone qualities were simulated in a model. Micromotions were significantly larger in the worst modeled cuff dysfunction (i.e. the supraspinatus and infraspinatus tendons were fully dysfunctional). Micromotions were also significantly different between conditions with healthy and poor bone quality. The implant’s initial stability was hardly influenced by a dysfunctional supraspinatus alone. However, when the infraspinatus was also affected, the glenohumeral joint force was displaced to the component’s rim resulting in larger micromotions and instability of the implant.  相似文献   
96.
Platelets have a central role in the development of arterial thrombosis and subsequent cardiovascular events. An appreciation of this complex process has made antiplatelet therapy the cornerstone of cardiovascular disease management. However, numerous patients will experience a recurrent atherothrombotic vascular event despite adequate antiplatelet therapy. Individual differences in the rate of platelet activation and reactivity markedly influence normal hemostasis and the pathological outcome of thrombosis. Such an individual variability is largely determined by environmental and genetic factors. These are known to either hamper platelets' response to agonists, and thereby mimic the pharmacological modulation of platelet function or mask therapy effect and sensitize platelets. In this article, we reviewed the antiplatelet mechanisms of aspirin and clopidogrel and the possible role of different polymorphisms, which may affect the efficacy of antiplatelet therapy. Heterogeneity in the way patients respond to aspirin and clopidogrel may in part reflect variation in cyclooxygenase (COX)-1, COX-2, glycoprotein (GP) Ib alpha, GP Ia/IIa, GP IIb/IIIa, UGT1A6*2, P2Y1, P2Y12, CYP2C9, CYP3A4 and CYP3A5 genotypes.  相似文献   
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OBJECTIVES: To explore measures of metabolic syndrome and glucose metabolism in families with exceptional longevity. DESIGN: Case–control study. SETTING: A university hospital in Leiden, the Netherlands. PARTICIPANTS: One hundred twenty‐one offspring of nonagenarian siblings, who were enriched for familial factors promoting longevity, and 113 of their partners. No subject had diabetes mellitus. MEASUREMENTS: Prevalence of metabolic syndrome was determined according to the criteria of the Third Report of the National Cholesterol Education Program. Glucose tolerance was assessed according to a 2‐hour oral glucose tolerance test. RESULTS: The offspring of nonagenarians siblings had a lower prevalence of metabolic syndrome (P=.03), similar body composition, lower mean fasting blood glucose levels (4.99 vs 5.16 mmol/L; P=.01), lower mean fasting insulin levels (5.81 vs 6.75 mU/L; P=.04), a higher mean homeostasis model assessment of insulin sensitivity (0.78 vs 0.65; P=.02), and a more‐favorable glucose tolerance (mean area under the receiver operating characteristic curve for glucose (13.2 vs 14.3; P=.007) than their partners. No significant differences were observed between the offspring and their partners in β‐cell function (insulogenic index 13.6 vs 12.5; P=.38). CONCLUSION: Despite similar body composition, the offspring of nonagenarian siblings showed a lower prevalence of metabolic syndrome and better glucose tolerance than their partners, centralizing the role of favorable glucose metabolism in familial longevity.  相似文献   
99.
Proximal migration is a complication in shoulder arthroplasty. Quantification of this phenomenon would help in identifying its cause. This study assessed the reliability of 4 methods of measuring proximal migration after shoulder arthroplasty on standard anteroposterior radiographs: the glenohumeral center-to-center measure, the glenohumeral arc measure, the acromiohumeral distance, and the scapular spine-humeral head center (spinohumeral) distance. Radiographs were taken of 12 embalmed shoulders, with matching metal humeral head replacements, in the neutral position and rotated both ways for 20 degrees along the vertical and horizontal axes. The measurements were tested for the reliability of the deviating projections against the neutral position, and an estimate of the interobserver and intraobserver reliability was made. Statistics included a paired t test and the interclass correlation coefficient. The acromiohumeral distance and spinohumeral center method proved most reliable. The spinohumeral center method was the least sensitive for projection errors, although only applicable as a relative measure. The coracoid process base can be used as a tell-tale sign for scapular projection.  相似文献   
100.
An approach for a better surgical exposure of the posterior part the glenoid and the rotator cuff is presented as an alternative for the long deltopectoral incision that might be considered in specially selected cases. In shoulder arthroplasty, it can be used for bone grafting to reorient the glenoid, revision of a glenoid component, or repair of a large rotator cuff tear. This posterosuperior approach consists of an osteotomy of the lateral rim and posterior corner of the acromion, with reflection of part of the medial and posterior insertion of the deltoid muscle. A special plate is used for stable fixation of the osteotomy. The method has been used since 1994 for shoulder prosthesis insertion in 79 patients. In 72 patients with a total shoulder or hemiarthroplasty, the cuff was attenuated or ruptured in 24 and could be repaired in 22. Twenty-two patients underwent a bony procedure to reorient the glenoid surface. The average correction of the superior tilt was 7 degrees . The external rotators are released from the bone and reattached, which might result in weakening of external rotation. This possible complication could not be confirmed at follow-up. The osteotomy healed in all but 1 patient. The fixation material had to be removed in 13.  相似文献   
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