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101.
Thyroid antibodies were determined by three different techniques in the sera of 125 children and adolescents with thyroid disorders and in the sera of 53 short, normal children without thyroid dysfunction. The incidence of antithyroglobulin antibodies in patients with thyroiditis was highest when measured by radioimmunoassay (85%), less than when measured by hemagglutination (24%), and least by antimicrosomal antibodies (7%). No patient who had initially negative serum for RATA subsequently had positive tests during follow-up of five to 24 months, whereas eight of 31 patients with initially negative serum for ATA later developed positive tests. Treatment appeared to have a suppressive effect on RATA, but not on ATA titers, in hypothroid patients with clinical thyroiditis. The incidence of hypothyroidism in the patients with clinical thyroiditis on initial presentation was significant (37%) and suggests that identification of children and adolescents with thyroiditis is important to ensure adequate medical follow-up.  相似文献   
102.
103.
Outdoor air was drawn by a vacuum system through a 0.8 μm molecular membrane filter and a back-up, refrigerated condenser from 8 A.M. to 5 P.M. daily during the 1982 ragweed-pollen season. Sample sets from each day were collected and stored separately. Condensate was collected in a freezing jacket, thawed, refiltered through a 0.45 μm filter, and lyophilized. Reconstituted condensates evoked wheal-and-flare skin reactions in a ragweed-sensitive individual and produced significant inhibition in an IgG-ELISA system by use of ragweed-pollen protein or ragweed antigen E conjugated to polystyrene microtiter plates, pooled serum of patients on ragweed immunotherapy, and alkaline phosphatase-labeled anti-human IgG. Earlier, in 1983 in this Journal, we reported the presence of airborne ragweed-pollen antigen in aerosol fractions below 5 μm. The present data demonstrate similar activity in filtrates well below the micronic range. Furthermore, these antigenic properties are substantially associated with atmospheric water vapor-either naturally or as a readily-induced result of the collection procedure. These results suggest that naturally occurring mists, although free of native particulates, may yet carry allergens of clinical significance.  相似文献   
104.
BackgroundThe objective of this study was to evaluate if not placing an indwelling urinary catheter leads to a higher potential for adverse genitourinary (GU) issues after total joint arthroplasty (TJA) under epidural anesthesia.MethodsThree hundred thirty-five consecutive patients who underwent primary TJA using epidural anesthesia were retrospectively reviewed. The initial 103 patients received a preoperative urinary catheter, which was maintained until the morning of postoperative day 1. The subsequent 232 patients did not receive a preoperative urinary catheter. Demographics, medical complications, GU complications, and length of stay were compared between groups.ResultsCompared between catheter and noncatheter groups, there were no differences in demographics including age, gender, or laterality of surgery. There was a difference in type of surgery (total knee arthroplasty vs total hip arthroplasty) (P = .008). There was no difference in American Society of Anesthesiologists score, but with a difference in body mass index (P = .01). There were no differences in GU complications among patients with benign prostatic hyperplasia or prostate cancer. However, among patients with a history of prostate disorders (benign prostatic hyperplasia or prostate cancer), urinary tract infection rate was higher in catheter group (P = .023). Postoperative GU complications were associated with increased median age in years and increased average length of stay in days.ConclusionPatients undergoing TJA under epidural anesthesia demonstrate no increased risk of postoperative urological complications without the placement of preoperative indwelling urinary catheter. The routine use of preoperative catheters can be reconsidered for this mode of anesthesia.Level of EvidenceLevel II, retrospective comparative study.  相似文献   
105.

Background

Concerns exist that women are underrepresented in trials of cardiovascular medications.

Objectives

The authors sought to examine women’s participation and the reported safety and efficacy by gender for pivotal cardiovascular disease (CVD) trials submitted to the U.S. Food and Drug Administration (FDA) supporting marketing applications.

Methods

On the basis of publicly available FDA reviews, the authors assessed enrollment of women in trials supporting 36 drug approvals from 2005 to 2015. Prevalence-corrected estimates for the participation of women were calculated as the percentage of women among trial participants divided by the percentage of women in the disease population (participation to prevalence ratio [PPR]), with a range between 0.8 and 1.2 reflecting similar representation of women in the trial and disease population. Sex differences in efficacy and safety were assessed.

Results

The proportion of women enrolled ranged from 22% to 81% (mean 46%). The calculated PPR by disease area was within or above the desirable range for atrial fibrillation (0.8 to 1.1), hypertension (0.9), and pulmonary arterial hypertension (1.4); PPR was <0.8 for heart failure (0.5 to 0.6), coronary artery disease (0.6), and acute coronary syndrome/myocardial infarction (0.6). The authors found little indication of clinically meaningful gender differences in efficacy or safety. Gender differences in efficacy or safety were described in labeling for 4 drugs.

Conclusions

Women were well represented in trials of drugs for hypertension and atrial fibrillation, and overrepresented for pulmonary arterial hypertension. Representation of women fell below a PPR of 0.8 for trials in heart failure, coronary artery disease, and acute coronary syndrome. Minimal gender differences in drug efficacy and safety profiles were observed.  相似文献   
106.

Objective

To determine the clinical significance of tachycardia in the postoperative period.

Patients and Methods

Individuals 18 years or older undergoing hip and knee arthroplasty were included in the study. Two data sets were collected from different time periods: development data set from January 1, 2011, through December 31, 2011, and validation data set from December 1, 2012, through September 1, 2014. We used the development data set to identify the optimal definition of tachycardia with the strongest association with the vascular composite outcome (pulmonary embolism and myocardial necrosis and infarction). The predictive value of this definition was assessed in the validation data set for each outcome of interest, pulmonary embolism, myocardial necrosis and infarction, and infection using multiple logistic regression to control for known risk factors.

Results

In 1755 patients in the development data set, a maximum heart rate (HR) greater than 110 beats/min was found to be the best cutoff as a correlate of the composite vascular outcome. Of the 4621 patients who underwent arthroplasty in the validation data set, 40 (0.9%) had pulmonary embolism. The maximum HR greater than 110 beats/min had an odds ratio (OR) of 9.39 (95% CI, 4.67-18.87; sensitivity, 72.5%; specificity, 78.0%; positive predictive value, 2.8%; negative predictive value, 99.7%) for pulmonary embolism. Ninety-seven patients (2.1%) had myocardial necrosis (elevated troponin). The maximum HR greater than 110 beats/min had an OR of 4.71 (95% CI, 3.06-7.24; sensitivity, 47.4%; specificity, 78.1%; positive predictive value, 4.4%; negative predictive value, 98.6%) for this outcome. Thirteen (.3%) patients had myocardial infarction according to our predetermined definition, and the maximum HR greater than 110 beats/min had an OR of 1.72 (95% CI, 0.47-6.27).

Conclusion

Postoperative tachycardia within the first 4 days of surgery should not be dismissed as a postoperative variation in HR, but may precede clinically significant adverse outcomes.  相似文献   
107.
Congestive heart failure in patients surviving aortic valve replacement has been associated with a high late mortality. To determine whether myocardial dysfunction in these patients occurred preoperatively, perioperatively, or during the early postoperative period, 19 consecutive patients undergoing aortic valve replacement using cardioplegia and hypothermia were studied by multiple-gated cardiac blood pool imaging. The resting ejection fractions for 8 patients with aortic stenosis did not show significant changes following operation. The 11 patients with aortic insufficiency had resting preoperative values of 58 ± 15%, which fell to 38 ± 18% immediately postoperatively (p < 0.01), with the late values being 51 ± 16%. Eight of the 18 patients (44%) showed deterioration of regional wall motion immediately after operation, which persisted in 3 during the late evaluation. The occurrence of new perioperative regional wall motion abnormalities and persistent perioperative depression in left ventricular function in some patients suggest the need for further improvement in myocardial protection during cardiopulmonary bypass for aortic valve replacement.  相似文献   
108.
109.
目的 研究通心络对大鼠心肌梗死后心肌炎症反应及肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)表达的影响.方法 应用结扎冠脉前降支的方法制备大鼠心梗模型,将SD大鼠随机分为3组:假手术组、心梗组、通心络干预组[2.0g/(kg·d)],应用组织病理学的方法观察术后1、2及4周梗死区与非梗死区炎性细胞浸润的情况;以半定量RT-PCR及蛋白免疫印迹(Western blot)的方法检测炎性因子TNF-α的表达情况.结果 心肌梗死后1周及2周,在心梗组及通心络干预组,梗死区与非梗死区炎性细胞浸润明显,至心肌梗死后4周,炎症反应消退,但TNF-α表达持续增加.通心络干预后炎性细胞浸润减轻,TNF-α表达降低.结论 通心络能减轻心梗后心肌炎症反应,降低炎性因子TNF-α的表达,发挥抗炎作用.  相似文献   
110.
《Brain stimulation》2014,7(1):66-73
BackgroundSwallowing problems following stroke may result in increased risk of aspiration pneumonia, malnutrition, and dehydration.Objective/hypothesisOur hypothesis was that three neurostimulation techniques would produce beneficial effects on chronic dysphagia following stroke through a common brain mechanism that would predict behavioral response.MethodsIn 18 dysphagic stroke patients (mean age: 66 ± 3 years, 3 female, time-post-stroke: 63 ± 15 weeks [±SD]), pharyngeal electromyographic responses were recorded after single-pulse transcranial magnetic stimulation (TMS) over the pharyngeal motor cortex, to measure corticobulbar excitability before, immediately, and 30 min, after real and sham applications of neurostimulation. Patients were randomized to a single session of either: pharyngeal electrical stimulation (PES), paired associative stimulation (PAS) or repetitive TMS (rTMS). Penetration-aspiration scores and bolus transfer timings were assessed before and after both real and sham interventions using videofluoroscopy.ResultsCorticobulbar excitability of pharyngeal motor cortex was beneficially modulated by PES, PAS and to a lesser extent by rTMS, with functionally relevant changes in the unaffected hemisphere. Following combining the results of real neurostimulation, an overall increase in corticobulbar excitability in the unaffected hemisphere (P = .005, F1,17 = 10.6, ANOVA) with an associated 15% reduction in aspiration (P = .005, z = −2.79) was observed compared to sham.ConclusionsIn this mechanistic study, an increase in corticobulbar excitability the unaffected projection was correlated with the improvement in swallowing safety (P = .001, rho = −.732), but modality-specific differences were observed. Paradigms providing peripheral input favored change in neurophysiological and behavioral outcome measures in chronic dysphagia patients. Further larger cohort studies of neurostimulation in chronic dysphagic stroke are imperative.  相似文献   
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