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AMPK在妊娠期糖尿病发病机制中的作用   总被引:1,自引:0,他引:1  
腺苷酸活化蛋白激酶是一种重要的蛋白激酶,主要作用是协调代谢和能量平衡.腺苷酸活化蛋白激酶被激活后,在增加骨骼肌对葡萄糖摄取、增强胰岛素敏感性、增加脂肪酸氧化以及调节基因转录等方面发挥重要作用.已经证实脂联素有调节糖脂代谢的作用,但其作用机制尚不十分清楚,很可能是通过腺苷酸活化蛋白激酶介导,对脂联素信号转导通路的研究将成为进一步理解脂联素作用的关键所在.而脂联素又是妊娠期糖尿病的预测因子,所以腺苷酸活化蛋白激酶逐渐成为对妊娠期糖尿病研究中的焦点.  相似文献   
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Ohne Zusammenfassung  相似文献   
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Four hundred and six patients presenting with shoulder pain underwent bilateral shoulder ultrasonography. Rotator cuff lesions were diagnosed in 197 patients. In 155 of the 308 patients who had additional arthrographic examinations, the arthrogram documented rotator cuff tears. Sixty-eight patients underwent surgery. There was good correlation between the ultrasonographic and arthrographic findings as well as the surgical results, with a sensitivity of 91% for each examination technique. Thirty-six postoperative patients were studied ultrasonographically; a minor to marked increase in rotator cuff echogenicity was demonstrated in them all. Its high predictive value makes ultrasonography the method of choice in diagnosing rotator cuff tears. Based on the evaluation of particular criteria, rotator cuff tears (greater than 1 cm) are commonly documented by ultrasonography. Only in patients with indeterminate or negative ultrasonograms in whom there is a high index of clinical suspicion, should arthrography be performed as a complementary imaging test. In postoperative follow-up the degree of scar formation at the reinsertion of the tendon is adequately documented by ultrasonography.  相似文献   
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Summary Since it has been suggested that gastric resections are followed by changes in bone metabolism, the aim of our study was to determine the biochemical parameters of bone metabolism and radial and lumbar bone density in 15 male ulcus patients treated by partial gastrectomy (Billroth II). Comparing the data with those of a corresponding control group, the lumbar bone density measured by quantitative computed tomography was statistically significantly lower (P < 0.04) in the patient group, whereas the peripheral bone mass of the distal part of the nondominant forearm measured by single-photon absorptiometry showed no statistically significant difference. In addition, a marked increase in alkaline phosphatase (P < 0.002) and urinary excretion of hydroxyproline (P < 0.003) was found in the gastrectomy group, whereas the 25-hydroxy-vitamin D levels were found to be significantly decreased (P < 0.04). Osteocalcin, a biochemical marker for osteoblast activity, and the carboxy-terminal propeptide of type I procollagen (PICP), a marker of collagen formation, were slightly but not significantly higher in gastrectomy-treated patients. The serum parathyroid hormone levels were similar in both groups. As none of the patients had any radiologic evidence of osteopenia, the changes in biochemical parameters of bone metabolism and bone mass in patients who had undergone partial gastrectomy could be a marker of latent bone loss.Abbreviations DPA/SPA dual/single-photon absorptiometry - BMD bone mineral density - QCT quantitative computed tomography - PICP carboxy-terminal propeptide of type I procollagen - 250HD3 25-hydroxy-vitamin D - iPTH parathyroid hormone - OC osteocalcin - BMC bone mineral content  相似文献   
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Treatment of idiopathic osteoporosis in the elderly presupposes exact radiological diagnosis, the exclusion of a primary illness as the cause of the pathological process and exact differential diagnosis from other metabolic osteopathies. We consider possible means of prevention of the immobilization of old people, and appropriate hormonal substitution in cases of previous illnesses which coincide with a disturbance of the gonadal function, as important prophylactic measures. In the case of manifest osteoporosis, if possible, an assignment of the disease to a manifestation with high or low bone turnover should be made, by means of biochemical adjuvants. In high bone turnover, the substitution of sex hormones or the administration of calcitonin is indicated, particularly if symptoms of pain are distinct. In osteoporosis with low bone turnover, fluoride in long-term therapy is the preferred medication. The latest studies show that a combination of fluoride and active vitamin D metabolites is preferable to monotherapy. All therapy for this disease, independent of the age of the patient, should be supported by isometric exercises, analgesics and appropriate dietary measures. Orthopaedic supporting measures should be applied only if conservative measures in acute vertebral fractures fail.  相似文献   
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目的研究臂丛神经损伤膈神经移位术对青壮年患者早期呼吸功能的影响.方法对16例接受膈神经移位治疗的患者,在术前、术后(10 d)进行肺功能指标的比较,同时定期进行门诊随访,观察呼吸系统自觉症状程度.结果13例术后出现了不同程度的供氧不足症状,16例全部出现一侧膈肌抬高,术后第10天肺活量(VC)、肺活量预计值百分数(VC%)分别比术前减少37.98%和26.88%,两者差异有统计学意义(tvc=11.532、tvc%=0,P<0.01).其它项目如残气量(RV)较术前轻度下降,肺总量(TLC)下降值达到术前肺总量的36.49%,残气量/肺总量比值(RV/TLC%)较术前上升了4.75%,上述各指标的差值均有统计学意义.1 s用力呼气量/用力肺活量比值(FEV1/FVC)和术前比基本无改变,但其差值有统计学意义.膈神经移位右侧(10例)与左侧(6例)术前、术后肺活量比较差异有统计学意义.术后随访8个月~2年,所有患者均无明显呼吸困难和胸闷等症状.结论膈神经移位术后对青壮年患者肺容量有较大的丧失,肺通气功能减弱和小气道阻力增加,但其丧失程度在机体自身代偿耐受范围内,不会导致急剧发生的严重呼吸功能障碍.建议对右侧臂丛神经根性损伤的患者,术前进行严格的肺、心功能检查,避免发生较为严重的并发症.  相似文献   
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