转化生长因子β与增殖性糖尿病视网膜病变

增殖性糖尿病视网膜病变（ＰＤＲ）是糖尿病患者致盲的主要原因,新生血管及纤维组织增殖是ＰＤＲ的主要病变。近几年的研究表明,转化生长因子β（ＴＧＦ－β）是具有同源双链的活性多肽,广泛存在于动物体多种组织和细胞内,是细胞的多功能调节因子。它既可促进细胞的增殖,也可抑制细胞的增殖,调节细胞外基质形成,同时对巨噬细胞有较强的趋化性,在新生血管形成及纤维组织增殖过程中发挥重要作用。本文对ＴＧＦ－β的上述主要生     

肝硬化患者肾脏血液动力学的研究

目的 研究肝硬化患者肾脏血液动力学的改变。方法 应用多普勒超声测定４２例肝硬化患者肾脏血液动力学指标。并分析这些指标与肝功能及平均动脉压之间的关系。结果 不同阶段的肝硬化患者肾内血管收缩程度有明显的差异。结论 肝硬化早期即有肾血管的收缩,肝功越差肾血管收缩越明显。肾血管的收缩是全身血液动力学改变的一部分。     

Presynaptic inhibition of synaptic transmission in the rat hippocampus by activation of muscarinic receptors: involvement of presynaptic calcium influx

1. Modulation of presynaptic voltage-dependent calcium channels (VDCCs) by muscarinic receptors at the CA3–CA1 synapse of rat hippocampal slices was investigated by using the calcium indicator fura-2. Stimulation-evoked presynaptic calcium transients ([Ca_pre]_t) and field excitatory postsynaptic potentials (fe.p.s.ps) were simultaneously recorded. The relationship between presynaptic calcium influx and synaptic transmission was studied.
2. Activation of muscarinic receptors inhibited [Ca_pre]_t, thereby reducing synaptic transmission. Carbachol (CCh, 10 μM) inhibited [Ca_pre]_t by 35% and reduced fe.p.s.p. by 85%. The inhibition was completely antagonized by 1 μM atropine. An approximate 4^th power relationship was found between presynaptic calcium influx and postsynaptic responses.
3. Application of the N-type VDCC-blocking peptide toxin ω-conotoxin GVIA (ω-CTx GVIA, 1 μM) inhibited [Ca_pre]_t and fe.p.s.ps by 21% and 49%, respectively, while the P/Q-type VDCC blocker ω-agatoxin IVA (ω-Aga IVA, 1 μM) reduced [Ca_pre]_t and fe.p.s.ps by 35% and 85%, respectively.
4. Muscarinic receptor activation differentially inhibited distinct presynaptic VDCCs. ω-CTx GVIA-sensitive calcium channels were inhibited by muscarinic receptors, while ω-Aga IVA-sensitive channels were not. The percentage inhibition of ω-CTx GVIA-sensitive [Ca_pre]_t was about 63%.
5. Muscarinic receptors inhibited presynaptic VDCCs in a way similar to adenosine (Ad) receptors. The percentage inhibition of ω-CTx GVIA-sensitive [Ca_pre]_t by Ad (100 μM) was about 59%. There was no significant inhibition of ω-Aga IVA-sensitive channels by Ad. The inhibitions of [Ca_pre]_t by CCh and Ad were mutually occlusive.
6. These results indicate that inhibition of synaptic transmission by muscarinic receptors is mainly the consequence of a reduction of the [Ca_pre]_t due to inhibition of presynaptic VDCCs.

     

原位PCR和免疫组化检测垂体腺癌P16基因

目的研究人垂体腺瘤P16基因的改变,同时探索原位PCR技术的适宜条件和结果确认,以及用于基因缺失检测的可行性。方法原位PCR和免疫组化技术。结界绝大部分间质细胞为P16蛋白免疫组化阴性,而一部分垂体肿瘤细胞呈P16阳性;针对P16基因的原位PCR信号则可见于垂体肿瘤细胞和间质细胞等各种细胞,即P16组化阴性的细胞同样表明有P16基因存在。结论原位PCR可以是P16基因研究的一种有效手段,提示垂体腺癌的P16基因改变形式可能主要是表达过度而不是基因缺失。     

敏感期内、末单眼斜视和剥夺猫视觉系统脑源性神经营养因子表达机理研究

目的观察和研究敏感期内、末不同时限单眼斜视
(monocularstrabismus,MS)和单眼剥夺(monoculardeprivation,
MD)幼猫视皮质、外侧膝状体的脑源性神经营养因子(brain
derivedneurotrophicfactor,BDNF)的可塑性变化。从形态学、分
子神经生物学角度探讨不同时限MS和MD幼猫视     

矿泉“851”对抗疟治疗的非特异性免疫作用

感染伯氏疟原虫(P.berghe ANKA株)小鼠,经矿泉“851”及与抗疟酮合用治疗后,腹腔巨噬细胞吞噬百分率和吞噬指数明显高于感染对照组(P<0.01)。两组药均能提高小鼠单核巨噬细胞系统(MPS)对碳微粒的廓清率,其K值与对照组相比,P<0.01,MPS活性的增强程度与其疟原虫的抑制率成正相关。     

中医药治疗糖尿病视网膜病变的临床与实验研究近况

综述了近年来中医药治疗糖尿病视网膜病变的研究状况及有待解决的问题。     

超声测量胎儿LL/FSTT预测胎儿体重

目的：探讨应用B型超声测量胎儿肝脏长度与胎儿股骨皮下组织厚度的比值（LL/FSTT）预测胎儿出生体重的临床价值。方法：用B型超声对400例胎儿双顶径、头围、腹围、股骨长度、肝脏长度与股骨皮下组织的厚度进行测量并分析与新生儿出生体重的关系。结果；肝脏长度与股骨皮下组织厚度的比值和胎儿体重密切相关（r=0.901）。对正常胎儿体重、巨大儿、胎儿宫内发育迟缓（IUGR）诊断的敏感性分别是88％、89％、86％，特异性分别是90％、92％、88％。结论：用胎儿肝脏长度与股骨皮下软组织厚度的比值预测胎儿体重的方法简单、准确，为临床掌握分娩时机和分娩方式提供可靠参考数据。