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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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Antibody to a 145-kilodalton outer membrane protein has bactericidal activity and protective activity against experimental bacteremia caused by a Brazilian purpuric fever isolate of Haemophilus influenzae biogroup aegyptius. The Brazilian Purpuric Fever Study Group. 总被引:2,自引:2,他引:0
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The immunologic basis for protection against Brazilian purpuric fever, a septicemic infection associated with Haemophilus influenzae biogroup aegyptius bacteremia, is unknown. Passive immunization of infant rats with antiserum to whole bacterial cells of the homologous strain protects them from experimental bacteremia following bacterial challenge. In immunoblotting, antibody to a 145-kDa protein (P145) was present in protective antisera but not in nonprotective antisera. As judged by analysis of the antibodies eluted from whole bacterial cells and the agglutination of bacteria by antisera to P145, this protein is surface exposed. We prepared monospecific rat antisera to this protein by three methods: (i) immunization with whole bacterial cells and absorption with a Brazilian purpuric fever strain not expressing P145, (ii) immunization with gel-purified P145, and (iii) immunization with a P145-expressing transformant of a laboratory H. influenzae strain expressing this protein and absorption of the antiserum with the laboratory H. influenzae strain. These antisera had low antilipooligosaccharide antibody titers, were reactive only with P145, and had bactericidal activity in vitro. Following passive immunization, these antisera partially protected infant rats from bacteremia resulting from intraperitoneal challenge with bacteria. As assessed by immunoblotting, pooled adult human sera contained antibodies reactive with P145. Antibody to P145 may contribute to protection against Brazilian purpuric fever. 相似文献
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臂丛神经根性损伤膈神经移位术对青壮年患者早期呼吸功能的影响 总被引:1,自引:1,他引:0
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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J. N. Banks S. J. Cox B. J. Northway R. H. Rizvi 《Food and Agricultural Immunology》1994,6(3):321-327
Monoclonal antibodies (MAbs) were raised against Penicillium aurantiogriseum var. melanoconidium. Cross‐reactivity studies were carried out against 12 ‘field’ and 27 ‘storage’ fungi. Two MAbs (MAbs 32 and 37) reacted with all of the fungi tested and a third (MAb 38) with 38 out of the 39 fungi (although weakly with some). Monoclonal antibodies 32 and 37, but not MAb 38, were found to react to a degree with ‘clean’ barley. Enzyme‐linked immunosorbent assay (ELISA) using MAb 38 and extracts of barley inoculated with the homologous antigen showed a clear relationship between absorbance and amount of fungal growth. It is suggested that these MAbs could be used in a broad‐spectrum assay to detect fungi of significance to the quality of foods and feeds. 相似文献
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Qu CF Song EY Li Y Rizvi SM Raja C Smith R Morgenstern A Apostolidis C Allen BJ 《Clinical & experimental metastasis》2005,22(7):575-586
Purpose: The urokinase plasminogen activator (uPA) and its receptor (uPAR) are expressed by pancreatic cancer cells and can be targeted
by the plasminogen activator inhibitor type 2 (PAI2). We have labeled PAI2 with 213Bi to form the alpha conjugate (AC), and have studied its in vitro cytotoxicity and in vivo efficacy.
Methods and Materials: The expression of uPA/uPAR on pancreatic cell lines, human pancreatic cancer tissues, lymph node metastases, and mouse xenografts
were detected by immunohistochemistry, confocal microscopy, and flow cytometry. Cytotoxicity was assessed by the MTS and TUNEL
assay. At 2 days post-cancer cell subcutaneous inoculation, mice were injected with AC by local or systemic injection.
Results: uPA/uPAR is strongly expressed on pancreatic cancer cell lines and cancer tissues. The AC can target and kill cancer cells
in vitro in a concentration-dependent fashion. Some 90% of TUNEL positive cells were found after incubation with 1.2 MBq/ml of AC.
A single local injection of ~222 MBq/kg 2 days post-cell inoculation can completely inhibit tumor growth over 12 weeks, and
an intraperitoneal injection of 111 MBq/kg causes significant tumor growth delay.
Conclusions: 213Bi-PAI2 can specifically target pancreatic cancer cells in vitro and inhibit tumor growth in vivo. 213Bi-PAI2 may be a useful agent for the treatment of post-surgical pancreatic cancer patients with minimum residual disease. 相似文献
10.
WANG Qing-sheng TA Na RAO Zhu-shi 《中国生物医学工程学报(英文版)》2007,16(4):148-154
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