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101.
102.
左旋氨氯地平治疗轻中度高血压疗效及不良反应的临床研究 总被引:14,自引:0,他引:14
目的:为评价左旋氨氯地平降压疗效及不良反应,并与氨氯地平相比较。方法:采用随机分组平行对照方法,将120例轻、中度高血压患者分成左旋氨氯地平组(60例),口服2.5~5mg·d~(-1)和氨氯地平组(60例),口服5~10mg·d~(-1)。观察5周。每周一次上午延迟1~4小时用药并测诊室谷值坐位血压、心率、观察不良反应。结果:5周未左旋氨氯地平与氨氯地平组治疗有效反应率分别为86.7%和83.3%,每组治疗前后比较差异非常显著(P<0.01)。组间比无显著性差异(P>0.05)。左旋氨氯地平组不良反应发生率6.7%,氨氯地平组为16.7%(P>0.05),但试验组不良反应程度更轻微。结论:左旋氨氯地平与氨氯地平治疗高血压同样有效,不良反应可能更小。 相似文献
103.
医用电气设备和系统电磁兼容性抗干扰设计方案的研究 总被引:1,自引:0,他引:1
依据现有电磁兼容性及医用电气设备安全通用要求的相关标准,主要从接地、屏蔽和滤波三个方面对我国现阶段医用电气设备和系统的电磁兼容性抗干扰设计方案进行探讨,希望借此为医用电气设备电磁兼容性的推广做一些有益的探索. 相似文献
104.
B O Cheng R P Trimble R J Illman B A Stone D L Topping 《The British journal of nutrition》1987,57(1):69-76
Adult male rats were fed on diets containing 100 g dietary fibre/kg either as alpha-cellulose or wheat bran or the pericarp-seed coat or aleurone layers prepared from that bran by sequential milling and air elutriation and electrostatic separation. After 10 d, concentrations of total volatile fatty acids (VFA) in caecal fluid were significantly different between groups and fell in the order: aleurone greater than wheat bran greater than pericarp-seed coat greater than cellulose. This ranking probably reflected the ease of fermentation of fibre polysaccharides by colonic bacteria which also resulted in a considerably higher faecal bacterial mass in the aleurone group. Because of the differences in the volume of caecal digesta, the mass of caecal VFA was considerably the highest in the aleurone group, intermediate with wheat bran and equally low in the pericarp-seed coat and cellulose groups. The diet based on aleurone gave a relatively higher proportion of propionate but with both pericarp-seed coat and wheat bran the contribution of butyrate was raised. VFA concentrations in hepatic portal venous plasma were proportional to caecal concentrations with very high (greater than 3 mM) values being recorded in the aleurone group. The findings are discussed in relation to the apparent susceptibility of the morphological components of wheat bran to fermentation by large bowel bacteria. 相似文献
105.
4-Aminopyridine (4-AP) induced an atropine- and tetrodotoxin (TTX)-insensitive contraction (resistant contraction), in a concentration-dependent manner, in the isolated jejunum of rabbits. The failure of specific antagonists of histamine, serotonin and substance P to affect this resistant contraction ruled out the participation of histamine, serotonin and/or substance P. Antiserum against neuropeptide Y (NPY) reduced this resistant contraction in a concentration-dependent manner and inhibited the action of 4-AP totally at a high concentration (1.25% dilution) whereas normal serum lacked this ability. This suggested that the release of NPY was involved in this 4-AP-induced resistant contraction. Radioimmunoassay of NPY-like immunoreactivity in isolated synaptosomal preparations indicated that 4-AP possessed the ability to induce the release of NPY. However, guanethidine did not affect the actions of 4-AP, indicating that NPY is released mainly from non-adrenergic nerves. Our results indicate that 4-AP induces the release of NPY from non-adrenergic nerves to produce an atropine- and TTX-resistant contraction in the isolated jejunum of rabbits. 相似文献
106.
107.
We have previously reported that the J774A.1 macrophage-like tumor cell line produces two potent monokines which stimulate the growth of osteoblasts and chondrocytes. These growth factors, which have an affinity for heparin-agarose, have been termed HEP I (a 30 Kd PDGF-like molecule) and HEP II (an approximately 20 Kd molecule), respectively, based on their elution profile. Unlike HEP I, HEP II does not stimulate the growth of fibroblasts. Extensive biological and chromatographic studies disclosed that HEP II appears to be a unique bone cell mitogen unlike any known growth factor, including the FGFs, IL-1s, and TNFs, EGF, IGF-I and -II, TGF-beta, beta 2 microglobulin, G-CSF, CSF-1 and GM-CSF. To characterize more fully the effects of the macrophage-derived monokines on osteoblast growth and function, clones were derived from calvaria explant cultures. Two clones, SDFRC-2.05 and SDFRC-3, were developed and found to exhibit osteoblastic characteristics, including high levels of alkaline phosphatase, synthesis of type I but not type III collagen, and an increased intracellular cAMP production in response to PTH. The SDFRC-3 cells exhibited a polygonal morphology like that of the explant-derived cells while SDFRC-2.05 cells exhibited a more fibroblastic morphology. When tested on the explant cultures and clones, HEP I and HEP II were found to stimulate DNA synthesis and increase protein per culture, but decreased alkaline phosphatase activity. Clone SDFRC-3 was found to be more responsive to HEP II than clone SDFRC-2.05. Both monokines were found to be more potent mitogens for bone cells than TGF-beta. HEP II, but not HEP I or TGF-beta, induced a transformation of bone cells from a polygonal to a fibroblastic morphology, suggesting the induction of migration prior to proliferation. Thus, macrophages may be responsible not only for bone repair but also for ensuring the linkage of bone formation to resorption during physiological remodeling. 相似文献
108.
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110.
计算机导航在骨科手术中的应用 总被引:3,自引:0,他引:3
目的将计算机导航技术应用于骨科手术,并对其进行初步分析。方法2004年2~12月,计算机导航系统辅助下共行134枚椎弓根螺钉固定,51枚股骨颈骨折空心钉内固定,58枚交锁髓内钉远端交锁螺钉固定。结果所有病例全部在导航下完成手术,术中明显减少C型臂X线机透视次数,未发生血管和神经损伤并发症。结论计算机导航手术安全有效,更有利于微创手术的开展。 相似文献