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71.
A M Abdel Gader A A Al-Mishari S A Awadalla N M Buyuomi T Khashoggi M Al-Hakeem 《International journal of gynaecology and obstetrics》2006,95(3):248-253
OBJECTIVE: To clarify the role played by tissue factor pathway inhibitor (TFPI) in pregnancy hypertension. METHODS: Using enzyme-linked immunosorbent assays, hemostatic measurements were obtained for women with pre-eclampsia (n=51), nonproteinuric hypertension of pregnancy (n=62), postpartum pre-eclampsia 24 h after childbirth (n=31), and no hypertension (healthy pregnant controls, n=100). RESULTS: There was a significant increase in circulating free TFPI levels in women with pre-eclampsia (9.7+/-6.2 ng/mL) or nonproteinuric hypertension of pregnancy (8.3+/-5.3 ng/mL) compared with healthy controls (5.3+/-2.1 ng/mL). In women with pre-eclampsia the levels remained elevated after placental delivery (10.6+/-4.0 ng/mL). Free protein S levels were significantly higher in women with pre-eclampsia (40.0%+/-10.7%), nonproteinuric hypertension of pregnancy (37.1%+/-12.5%), or postpartum pre-eclampsia (39.3%+/-9.1%) than in healthy pregnant controls (32.2%+/-8.5%). CONCLUSION: Increased levels of the physiologically active free forms of TFPI and free protein S, 2 coagulation inhibitors, may protect women with pregnancy-induced hypertension from the risks of hemostatic activation. 相似文献
72.
白细胞介素6、信号传导和转录活化因子3和血管内皮生长因子在人脑胶质瘤中的表达及相关性研究 总被引:11,自引:11,他引:0
目的研究人脑不同级别胶质瘤中白细胞介素(IL)-6,信号传导和转录活化因子3(STAT3)和血管内皮生长因子(VEGF)的表达,探讨IL-6、STAT3和VEGF与肿瘤病理级别和侵袭性的关系。方法采用免疫组织化学法,检测70例人脑胶质瘤,10例脑膜瘤和5例正常脑组织中IL-6、STAT3和VEGF的表达。结果胶质瘤中IL-6、STAT3和VEGF的表达水平在高级别组(Ⅲ、Ⅳ级)明显高于低级别组(Ⅰ、Ⅱ级),两组间差异有统计学意义(P〈0.01),STAT3的表达与IL-6和VEGF的表达均呈正相关(P〈0.01)。结论IL-6、STAT3和VEGF的表达与胶质瘤的恶性程度有密切关系;且三者协同在胶质瘤发生、发展过程中起重要作用。三者的相关性证实VEGF基因由STAT3蛋白调节,而STAT3又由IL-6刺激活化。 相似文献
73.
介导感觉生理功能的瞬时受体电位通道蛋白(TRP)家族研究进展 总被引:1,自引:0,他引:1
瞬时受体电位通道蛋白(TRP)家族由一类特殊的阳离子通道蛋白组成,在神经细胞及其他非兴奋细胞中有重要作用,其中在介导多种感觉生理功能方面的作用尤其显著.TRP结构与功能的深入研究为阐明感觉生理功能的分子机制提供了重要线索.本文综述TRP家族在温度感受、机械刺激感受、光感受和化学信号感受等方面的研究进展. 相似文献
74.
目的探讨人膀胱移行细胞癌信号转导相关基因的表达变化。方法使用人肿瘤基因表达谱芯片检测11例膀胱移行细胞癌组织基因表达谱的变化,以寻找与细胞信号转导相关的差异表达基因。结果以正常膀胱黏膜组织为对照,11例膀胱肿瘤组织中有87个基因表达明显下调,102个基因表达明显上调。其中与细胞信号转导相关的差异表达基因有35个,明显上调基因13个,明显下调基因22个。结论膀胱肿瘤的发生与发展与多种细胞信号转导相关基因的异常表达有关。 相似文献
75.
Surojit Paul Peter Olausson Deepa V Venkitaramani Irina Ruchkina Timothy D Moran Natalie Tronson Evan Mills Shawn Hakim Michael W Salter Jane R Taylor Paul J Lombroso 《Neuropsychopharmacology》2007,61(9):1049-1061
BACKGROUND: Formation of long-term memories is critically dependent on extracellular-regulated kinase (ERK) signaling. Activation of the ERK pathway by the sequential recruitment of mitogen-activated protein kinases is well understood. In contrast, the proteins that inactivate this pathway are not as well characterized. METHODS: Here we tested the hypothesis that the brain-specific striatal-enriched protein tyrosine phosphatase (STEP) plays a key role in neuroplasticity and fear memory formation by its ability to regulate ERK1/2 activation. RESULTS: STEP co-localizes with the ERKs within neurons of the lateral amygdala. A substrate-trapping STEP protein binds to the ERKs and prevents their nuclear translocation after glutamate stimulation in primary cell cultures. Administration of TAT-STEP into the lateral amygdala (LA) disrupts long-term potentiation (LTP) and selectively disrupts fear memory consolidation. Fear conditioning induces a biphasic activation of ERK1/2 in the LA with an initial activation within 5 minutes of training, a return to baseline levels by 15 minutes, and an increase again at 1 hour. In addition, fear conditioning results in the de novo translation of STEP. Inhibitors of ERK1/2 activation or of protein translation block the synthesis of STEP within the LA after fear conditioning. CONCLUSIONS: Together, these data imply a role for STEP in experience-dependent plasticity and suggest that STEP modulates the activation of ERK1/2 during amygdala-dependent memory formation. The regulation of emotional memory by modulating STEP activity may represent a target for the treatment of psychiatric disorders such as posttraumatic stress disorder (PTSD), panic, and anxiety disorders. 相似文献
76.
目的:研究临床路径在大肠癌手术患者中的应用效果。方法:选择广东省江门地区某三甲医院2006年7月至2007年12月间实施临床路径的大肠癌手术患者192例作为实验组,对照组选择该院2005年1月至2006年6月间未实施临床路径按常规模式实施的大肠癌手术患者174例,比较两组患者在住院日、住院费用、患者满意度等方面有无差异性。结果:实验组患者的平均住院日、住院费用等方面明显低于对照组(P<0.01),患者满意度优于对照组(P<0.01)。结论:按临床路径对大肠癌手术患者实施围手术期诊疗护理计划,可减少患者平均住院日,降低住院费用,提高医疗护理服务质量及患者满意度,为进一步扩大临床路径的临床应用范围提供实验数据。 相似文献
77.
Hyung Bin Park Mihee Koh Se Hyun Cho Brian Hutchinson Bonghee Lee 《Journal of orthopaedic research》2005,23(6):1419-1424
The anterior cruciate ligament (ACL) serves as the primary restraint to anterior tibial translation. In addition to this biomechanical function, the ACL appears to have a function in neuromuscular control. This hypothesis was formulated after the discovery of mechanoreceptors within the ACL. The full somatosensory pathway from the ACL to the cerebrum has yet to be elucidated. In order to map this sensory pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus (PRV). The pseudorabies virus was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6-7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocellular reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. This finding suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings. 相似文献
78.
Najet Rebai Guillermina Almazan Ling Wei Mark I. Greene H. Uri Saragovi 《The European journal of neuroscience》1996,8(2):273-281
A surface receptor complex of M r ˜65 000 (p65) and ˜95 000 (p95) is expressed in cells of the central nervous system of mice. This receptor is recognized by monoclonal antibody 87.92.6 or by reovirus type 3 haemagglutinin as unnatural ligands. The p65/p95 receptor is expressed mostly in neural embryonic precursors undergoing proliferation, especially those in the S-G2 phase of the cell cycle. Receptor expression decreases progressively throughout embryogenesis to low but detectable levels in the adult brain. Biochemical characterization revealed that the neural p65/p95 receptor complex is indistinguishable from the p65/p95 receptor expressed in T cells, where receptor ligation leads to a mitogenic block. In neural and lymphoid tissues the p65/p95 receptor (or an associated protein) possesses a tyrosine kinase enzymatic activity. Receptor ligation in neural cells resulted in the rapid tyrosine phosphorylation of cellular proteins which are different from substrates phosphorylated in T cells. Differential substrate coupling to the receptor may account for differences in signal transduction and biology between neural cells and T cells. Further study of this receptor complex may help define important features of neural proliferation, differentiation and survival. 相似文献
79.
José Manuel Valdueza Loris Cristante Jörg Freitag Christian Hagel Hans-Dietrich Herrmann 《Neurosurgical review》1995,18(4):273-275
The clinical, neuroradiological, and histological findings of an adult patient suffering from malignant optic glioma is reported. Rapid visual deterioration was misdiagnosed for several months until biopsy confirmed the tumor. The patient died despite radiation therapy nine months after first symptoms. Our presentation will focus on the problems of diagnosing and establishing therapeutic procedures in this rare malignant neoplasm. 相似文献
80.
介绍供医用超声功率计用的两种高频、宽增益的小信号放大器,并比较了它们彼此的优缺点。 相似文献