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461.
正一项针对全球195个国家的18亿10-24岁的青少年健康状况的调查研究显示,这些年轻人正面临比25年前更大的健康挑战。文章称,目前的10~24岁的人口是有史以来最多的,截至2016年达到18亿,印度和中国拥有全球三分之一的青少年(6.22亿)。印度青少年人口增长了40%,然而,中国青少年人口从1990年的3.52亿减少到2016年的2.53亿。2016年青少年的DALYs为2.53亿,非传染性疾病(NCD)占青少年疾病负担的56%(1.42亿),NCD是所有国家青年人健康状况每况愈下的主要  相似文献   
462.
We report an unusual occurrence of involuntary movement involving the tongue in a patient with confirmed Wilson''s disease (WD). She manifested with slow, hypophonic speech and dysphagia of 4 months duration, associated with pseudobulbar affect, apathy, drooling and dystonia of upper extremities of 1 month duration. Our patient had an uncommon tongue movement which was arrhythmic. There was no feature to suggest tremor, chorea or dystonia. It might be described as athetoid as there was a writhing quality, but of lesser amplitude. Thus, the phenomenology was uncommon in clinical practice and the surface of the tongue was seen to “ripple” like a liquid surface agitated by an object or breeze. Isolated lingual dyskinesias are rare in WD. It is important to evaluate them for WD, a potentially treatable disorder.  相似文献   
463.
A preponderance of evidence from systematic reviews supports the effectiveness of weight‐bearing exercises on bone mass accrual, especially during the growing years. However, only one systematic review (limited to randomized controlled trials) examined the role of physical activity (PA) on bone strength. Thus, our systematic review extended the scope of the previous review by including all PA intervention and observational studies, including organized sports participation studies, with child or adolescent bone strength as the main outcome. We also sought to discern the skeletal elements (eg, mass, structure, density) that accompanied significant bone strength changes. Our electronic‐database, forward, and reference searches yielded 14 intervention and 23 observational studies that met our inclusion criteria. We used the Effective Public Health Practice Project (EPHPP) tool to assess the quality of studies. Due to heterogeneity across studies, we adopted a narrative synthesis for our analysis and found that bone strength adaptations to PA were related to maturity level, sex, and study quality. Three (of five) weight‐bearing PA intervention studies with a strong rating reported significantly greater gains in bone strength for the intervention group (3% to 4%) compared with only three significant (of nine) moderate intervention studies. Changes in bone structure (eg, bone cross‐sectional area, cortical thickness, alone or in combination) rather than bone mass most often accompanied significant bone strength outcomes. Prepuberty and peripuberty may be the most opportune time for boys and girls to enhance bone strength through PA, although this finding is tempered by the few available studies in more mature groups. Despite the central role that muscle plays in bones' response to loading, few studies discerned the specific contribution of muscle function (or surrogates) to bone strength. Although not the focus of the current review, this seems an important consideration for future studies. © 2014 American Society for Bone and Mineral Research.  相似文献   
464.

Background

Pharmacoepidemiologic analysis can confirm whether drug efficacy in a randomized controlled trial (RCT) translates to effectiveness in real settings. We examined methods used to control for immortal time bias in an analysis of renin–angiotensin system (RAS) inhibitors as the reference cardioprotective drug.

Methods

We analyzed data from 3928 patients with type 2 diabetes who were recruited into the Hong Kong Diabetes Registry between 1996 and 2005 and followed up to July 30, 2005. Different Cox models were used to obtain hazard ratios (HRs) for cardiovascular disease (CVD) associated with RAS inhibitors. These HRs were then compared to the HR of 0.92 reported in a recent meta-analysis of RCTs.

Results

During a median follow-up period of 5.45 years, 7.23% (n = 284) patients developed CVD and 38.7% (n = 1519) were started on RAS inhibitors, with 39.1% of immortal time among the users. In multivariable analysis, time-dependent drug-exposure Cox models and Cox models that moved immortal time from users to nonusers both severely inflated the HR, and time-fixed models that included immortal time deflated the HR. Use of time-fixed Cox models that excluded immortal time resulted in a HR of only 0.89 (95% CI, 0.68–1.17) for CVD associated with RAS inhibitors, which is closer to the values reported in RCTs.

Conclusions

In pharmacoepidemiologic analysis, time-dependent drug exposure models and models that move immortal time from users to nonusers may introduce substantial bias in investigations of the effects of RAS inhibitors on CVD in type 2 diabetes.Key words: cardiovascular disease, immortal time bias, renin–angiotensin system inhibitors, time-dependent Cox model, cancer, type 2 diabetes  相似文献   
465.
Background: To evaluate the cases of mandibular fractures treated by open reduction and rigid fixation at the Armed Forces Medical College, Pune.  相似文献   
466.
467.
Antiphospholipid antibodies and venous thromboembolism   总被引:14,自引:2,他引:14  
The clinical relevance of antiphospholipid antibodies (APLA) in patients without systemic lupus erythematosus who have venous thromboembolism (VTE) in unknown. Limited evidence suggests that there is an association between the presence of APLA and both initial and recurrent episodes of VTE and that patients with APLA and VTE are resistant to warfarin therapy. Unselected patients with a first episode of clinically suspected deep vein thrombosis or pulmonary embolism were evaluated with objective tests for VTE and with laboratory tests for APLA; the latter included tests for the lupus anticoagulant (LA) and anticardiolipin antibodies (ACLA). Patients with VTE were treated with anticoagulant therapy and observed during and after discontinuation of anticoagulants for symptomatic recurrence of VTE. There was a strong association between LA and VTE (odds ratio, 9.4; 95% confidence interval [CI], 2.1 to 46.2) and 9 to 65 (14%; 95% CI, 7% to 25%) patients with VTE had LA. There was no association between the presence of ACLA and VTE (odds ratio, 0.7; 95%CI, 0.3 to 1.7) because of the high frequency of positive ACLA assays in patients without VTE. None of the 16 patients with VTE and APLA developed recurrent VTE while receiving warfarin therapy. There was no difference in rates of recurrent VTE in patients with or without APLA after anticoagulant therapy was discontinued. The strong association between LA and VTE suggests that testing for LA in patients with VTE is useful. The measurement of ACLA in patients with VTE has no clinical usefulness because the results are abnormal in a high proportion of patients without VTE. Although the presence of APLA in patients with VTE was not associated with resistance to a conventional intensity of warfarin or an increased risk of recurrent VTE after discontinuation of warfarin, a larger study should address these issues in a subgroup of patients with VTE and LA.  相似文献   
468.
SUMMARY The aim of this pilot study was to evaluate the efficacy and safety of lansoprazole plus clarithromycin for eradication of Helicobacter pylori. A total of 26 patients with H. pylori infection were randomised to receive clarithromycin, 500 mg t.i.d. for 14 days, plus either lansoprazole, 30 mg o.m., (group L30, n=13) or lansoprazole, 30 mg b.i.d., (group L60, n=13). H. pylori status was determined pre-treatment and four to six weeks after completion of the study medication by histology and 13C-urea breath test. Two patients were unable to complete the course of medication. Of the remaining 24 patients, 14 (58%) successfully eradicated H. pylori — 8/12 (67%) patients in group L30 and 6/12 (50%) in group L60. Side-effects were experienced by 17/26 (65%) of patients, most commonly a taste disturbance. The results from this pilot study suggest that dual therapy with lansoprazole plus clarithromycin is only a moderately effective regimen for eradicating H. pylori.  相似文献   
469.
Twenty pituitary adenomas were studied using light microscopy, immunohistochemistry and electron microscopy. Based on clinical manifestations of hormonal hypersecretion they were divided into two groups, i.e. group-I (12 patients) with no endocrine dysfunction and group-II (8 patients) with endocrine dysfunction. Group-I could be further sub-divided into two groups based on IHC : group LA in which no hormone could be localised in the tissue (null cell adenomas) and group IB where hormones could be localised in the tissue (1). Tumours in group II, with light microscopy, were acidophil (n=5), basophil (n=1) or mixed (n=2) adenomas. Eight of these 20 cases were plurihormonal. Growth hormone, and prolactin were the commonest combination. This study has helped in the reclassification of the pituitary adenomas according to the hormone they produce.KEY WORDS: Pituitary neoplasms, Diagnosis, Immunohistochemistry, Electron microscopy  相似文献   
470.
Fifteen patients with lymphoma and hypercalcemia (greater than or equal to 11.0 mg/dL) were identified by screening the serum chemistry profile obtained from patients upon admission to the Los Angeles County/USC Medical Center. Seven of the 15 (47%) possessed a frankly elevated serum concentration of 1,25-dihydroxyvitamin D [1,25-(OH)2-D]. An additional patient with severe hypercalcemia (16.2 mg/dL) had a serum 1,25-(OH)2-D concentration in the midnormal range, not a suppressed value. To examine the potential existence of hypercalciuria in absence of overt hypercalcemia, prospective screening of 23 normocalcemic patients with lymphoma was undertaken. Four of the 23 patients (17%) had increased fractional urinary calcium excretion rates (0.35 +/- 0.3 mg calcium/100 mL glomerular filtrate [GF], mean +/- SE; normal, less than 0.16 mg/100 mL GF); two of the hypercalciuric patients had a frankly elevated serum 1,25-(OH)2-D concentration. Of the 19 hypercalcemic/hypercalciuric lymphoma patients identified, none had an elevated serum immunoreactive parathyroid hormone concentration. Fourteen of the 19 hypercalcemic/hypercalciuric patients (74%) suffered from B-cell neoplasms, three had Hodgkin's lymphoma, and two had adult T-cell leukemia/lymphoma. All hypercalcemic/hypercalciuric patients had widespread disease (stage III or IV). Six patients, four with hypercalcemia and two with hypercalciuria, had acquired immunodeficiency syndrome (AIDS). These data suggest that the deregulated synthesis of a 1,25-(OH)2-D-like metabolite is a common cause of hypercalcemia and hypercalciuria in patients with lymphoma including patients with AIDS-associated tumors.  相似文献   
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