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1.
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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The relaxant effects of electrical field stimulation (EFS) and exogenously applied acetylcholine (ACh) or acidified NaNO2 (a-NaNO2) were investigated in the isolated mouse corpus cavernosum precontracted with phenylephrine hydrochloride (PE). Tetrodotoxin (TTX) blocked the relaxant effects of EFS completely, whereas it had no effect on the responses to ACh or a-NaNO2. Guanethidine and indomethacin failed to affect the electrically or ACh-induced relaxations. Atropine completely blocked the effect of ACh; however, it caused a slight reduction in the relaxation evoked by EFS.N G- Nitro-l-arginine (l-NOARG) reduced the effects of EFS and ACh significantly, but it was ineffective on the relaxations induced by a-NaNO2. The inhibitory action ofl-NOARG was partly restored byl-arginine, but not byd-arginine. Methylene blue (MB) and hydroxocobalamin (HC) exhibited significant inhibition on the relaxations evoked by EFS, ACh and a-NaNO2. Hydroquinone (HQ) reduced relaxation due to a-NaNO2, but did not affect that of EFS and ACh. Our findings suggest that EFS-induced relaxations of mouse cavernosal tissue are mediated by a transmitter which probably resembles an organic nitrate.  相似文献   
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Radius, ulna, short bones (RUS), carpal (CARP) bone age (BA), tibial corticodiaphyseal (C/D) ratio and trabecular aspect were assessed in 19 children with steroid dependent nephrotic syndrome and 15 age matched healthy children. Both RUS and CARP BA were significantly lower than in the controls. Trabecular aspect and tibial C/D ratio did not show any statistical significance. There was a positive correlation between HSDS and RUS BA delay (r=−0.476, p<0.05); CARP BA delay and RUS BA delay (r=0.563, p<0.01) and RUS BA and CARP BA (r=0.891, p<0.001). In conclusion, RUS and CARP BA are both retarded and positively correlated in steroid dependent nephrotic children.  相似文献   
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Extracorporeal septoplasty is a radical solution for the severely deviated nose. The major problems associated with this procedure are fixation of the septal cartilage graft and dorsal irregularities. Extracorporeal septoplasty was performed in combination with open rhinoplasty in 17 patients with severe nasal deformities. In this technique septum was totally removed through the columellar incision of open rhinoplasty, corrected outside, and replaced as a free ``L' shaped cartilage graft. The cartilage graft was fixated to the upper lateral cartilages to restore the natural relations of the anatomical structures. Additional rhinoplastic manipulations were also performed. The follow-up period was up to 18 months. The overall result was successful in all patients. Nasal deviation did not recur and secondary revisions were not needed for any patient during follow-up.  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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It is reported that some types of insects have a remarkable ability to detect the direction of an incident sound even though its acoustic sensory organs are in very close proximity each other. Maybe the ears are jointed by a cuticular structure with which the separated motions can be coupled mechanically and thus be magnified. In this paper, a detailed model is setup to describe the principle of this type of localization using a mechanical coupled structure. The transfer functions and the responses of the model in terms of time and frequency are analyzed to describe the mechanism of its ability of directional hearing. This analytical model provides a method to design the experimental model for the predetermined incident sound pressure, and the analysis of this model shows that this structure have the ability to determine the direction of the incident stimulus.  相似文献   
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Several problems in the management of life-threatening mucormycosis remain unresolved, necessitating new methods of management. Four patients with histopathologically proven rhinocerebral mucormycosis were treated with high cumulative doses of granulocyte colony-stimulating factor (G-CSF). All had multiple predisposing factors for mucormycosis, particularly leukemia and neutropenia. Two patients refractory to fluconazole therapy were treated with liposomal amphotericin B. The improvement in clinical manifestations was closely related to neutrophil recovery, and all patients were alive at the end of therapy. In addition to surgical debridement and antifungal therapy, G-CSF seems to have played a role in their survival.  相似文献   
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