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101.
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
102.
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
103.
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
104.
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
105.
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107.
对1例巨大甲状腺肿瘤患者在体外膜肺氧合辅助下行肿瘤切除术,手术顺利,历时12.0h,切除肿瘤500g,住院23d患者康复出院。提出术前充分评估患者状况、做好心理护理和器械物品准备,术中熟悉体外膜肺氧合的操作方法、积极配合手术、密切观察病情等,是获得良好手术效果的重要环节。 相似文献
108.
深圳市福田区暗娼艾滋病KAP调查分析 总被引:1,自引:0,他引:1
目的:探讨暗娼艾滋病KAP的现状,为艾滋病预防控制中的咨询、外展及其它健康教育活动提供依据。方法:在“城中村”中随机抽取55位暗娼,由经过专门培训的调查员调查并采血检验。结果:暗娼艾滋病平均知晓率为73.88%;与艾滋病相关的高危行为,呈现低龄化、职业化的倾向;为了预防艾滋病,绝大部分暗娼愿意坚持使用安全套,但实际情况并不如人意;暗娼获得艾滋病知识及相关服务并不方便;梅毒检出率为9.09%。结论:打工者的性权利长期被忽视,使卖淫拥有很大的市场,这是暗娼们乃以存在并长久不衰的重要原因之一;暗娼艾滋病知晓率有了较大提高,可能与深圳市开展艾滋病防制工作较早、力度较大有关;安全套使用率还有待提高:艾滋病外展服务亟待开展与加强。 相似文献
109.
目的探讨术中实时超声导航在脑动静脉畸形(AVM)外科治疗中的应用价值。方法26例脑AVM显微手术切除术中,使用Aloka SSD 4000型超声检查仪扫描,进行AVM定位、辨别供血动脉和引流静脉;确定血肿与AVM的关系以及血流动力学监测。病变切除后重复超声检查AVM残留与否,并与术后脑血管造影结果对比。结果26例畸形血管团均住实时超声下清晰显示并获得全切除。血肿区为高同声无血流信号;供血动脉与正常血管在血流动力学上有差别;术中超声影像所示的病变全切除为术后血管造影所证实。结论术中实时超声能够对脑AVM进行准确定位,指导皮质切口的设计,并可判定病灶是否全切除.对于术前的MRI、DSA检查起到很有价值的补充作用。 相似文献
110.
Ting-Kai Leung Chien-Jui Cheng Chi-Ming Lee Li-Kuo Shen Hung-Jung Wang Ya-Yen Chen 《中华医学杂志(英文版)》2005,118(17):1493-1496
The current report focuses on two patients of the same age who presented similar appearances on initial anteroposterior chest images. Follow-up images showed superoanterior and superoposterior mediastinal lesions. The first patient with noninvasive cystic thymoma was suspected before surgery, while the pathologic diagnosis was intrathoracic phrenic nerve schwannoma. The second patient was with an asymmetric, dumbbell-shaped paravertebral tumor over T3 and T4 on the left side. The preoperative… 相似文献