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991.
Experiments on dogs showed that if the specific adrenergic receptors of the blood vessel wall (- and -receptors) were blocked by phentolamine or inderal it still continued to produce tissue blood clotting factors after stimulation of the vagus nerve. No response of this type was observed to stimulation of the nerve after the cholinergic receptors had been blocked by atropine. It is concluded that hyperfibrinolysis and hypercoagulation developing after vagus nerve stimulation are due to excitation of cholinergic structures.Department of Normal Physiology, Chita Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. N. Filatov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 8, pp. 19–22, August, 1974.  相似文献   
992.
邱坚 《医学信息》2005,18(8):866-868
医学科技创新是医院赖以生存与发展的动力,医学科技创新的过程也是医学知识模式不断转换的过程,本文从知识模式转换的视角,探讨知识管理对医学科技创新的意义与作用  相似文献   
993.
利用旋转壁式生物反应器(Rotating wall vessel,RWV)体外培养脐带血干细胞,使其大量扩增,以满足临床应用对造血干/祖细胞的数量与质量要求。从脐带血分离得到的单个核细胞(Mononuclear cells,MNC)在T-flask中培养24h,之后接种到RWV反应器中,培养200h。每24h细胞计数,测量培养基的pH和渗透压变化;在144h和197h测CD34 细胞含量并做CFU-GM半固体培养。有核细胞(Nucleated cells,NC)与CD34 细胞在第197h,分别扩增了435.5±87.6倍和32.7±15.6倍,CFU-GM(Colony-forming unit-granulocyte/macrophage)细胞扩增了21.7±4.9倍。整个培养过程中,RWV反应器中的pH和渗透压都保持在造血细胞最佳的扩增条件内,pH基本保持在7.2~7.4之间,渗透压基本保持在290~310mmol/kg之间。由于旋转壁式生物反应器(RWV)结构上的特殊性,可以保证细胞在悬浮流动的状态下生长,很好地模拟了脐带中的造血微环境,使脐带血造血干细胞在该反应器中短期内得到大量扩增。  相似文献   
994.
报道美国纽约地区9例播散性弓形虫病尸检材料,均有脑部病变,8例累及心脏,4例累及肺脏,尚见胰腺、消化道、甲状腺、淋巴结、泌尿生殖器官等受累。其中弓形虫性脑炎9例,心肌炎4例,肺炎3例,胰腺炎2例。仅脑炎、肺炎产牛症状,经脑CT扫描、弓形虫抗体测定提示本病,并经涂片、骨髓活检和尸检证实,以查见弓形虫为依据。临床以神经精神症状和肺部感染症状为主。病变分为静止(潜伏)、组织坏死、炎症反应及增生修复四种状态,强调囊型弓形虫形态学识别的诊断意义。  相似文献   
995.
Gastrointestinal polyps are common lesions that usually present singly or in small numbers. Although the term ‘multiple colorectal polyposis’ was originally applied to patients carrying at least 100 large intestinal adenomas, it has subsequently become broadened to include patients carrying multiple polyps regardless of their nature. Most of the non-adenomatous polyposis syndromes are hereditary. They can be classified according to the dominant type of polyp, their distribution in the gastrointestinal tract and their potential for the development of gastrointestinal cancers. This review summarises their main clinical, genetic and histopathological features.  相似文献   
996.
The adhesive-aggregative activity of the platelets and the rate of blood clotting were compared in 125 healthy subjects during an emergency adaptation reaction (emotional stress, ACTH loading) and in 157 patients with heart and circulatory diseases during the period of crisis, and also during acute drug therapy. Changes in the platelets and plasma-coagulative components of hemostasis were found to be opposite in direction, and on this basis new ideas were put forward to explain the hemostatic function of the platelets.Department of Internal Medicine, Kuban Red Army Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 12, pp. 669–672, December, 1979.  相似文献   
997.
Clues to mechanisms regulating development and tumorigenesis may be provided by studies of unusual diseases. Beckwith-Wiedemann syndrome (BWS) is a rare congenital disorder apparently related to abnormal regulation of insulin-like growth factor-2 (IGF-2) production. IGF-2 mRNA has been previously localized to the chief cells of extra-adrenal paraganglia and to adult, but not fetal, adrenal medulla. Expression of IGF-2 by neuroblastomas has been hypothesized to reflect extra-adrenal paraganglionic differentiation. In the adrenals of a fetus with BWS, we have observed both increased numbers of chromaffin cells and organoid nodules resembling extra-adrenal paraganglia. Immunoreactive IGF-2 was observed in both cell types, but was also observed in chromaffin cells in the normal fetal adrenal. The findings suggest autocrine or paracrine influences of IGF-2 in regulating the number and phenotype of cells derived from sympathoadrenal precursors in the developing adrenal medulla as well as in extra-adrenal paraganglia. These results have implications for the interpretation of data from neuroblastoma studies.  相似文献   
998.
A case of low grade fever developing about a month before the discovery of gastric carcinoma is reported. No findings of infection or collagen disease were revealed. The fever continued for about 3 months, but promptly disappeared after surgical removal of the tumor. A superficial spreading mucosal carcinoma with minimal invasion to the sub-mucosa was seen in the antrum, showing the features of poorly differentiated adenocarcinoma. In addition, unique venous inflammation was recognized beneath and around the neoplasm. Arteries and lymph vessels did not exhibit any inflammatory changes. It was presumed that the gastric carcinoma had induced phlebitis, which subsequently brought about the fever. As to the pathogenetic mechanism, it was suggested that a substance produced by the carcinoma cells flowed into nearby veins to induce the phlebitis. Acta Pathol Jpn 42 : 293-297, 1992.  相似文献   
999.
儿童臀肌挛缩症免疫发病机理的研究   总被引:4,自引:0,他引:4  
本文对41例儿童臀肌挛缩症患者外周血及32例儿童臀肌挛缩症臀肌进行了系统的免疫学研究。结果表明:儿童臀肌挛缩症患者免疫调节功能紊乱,红细胞免疫功能低下,臀肌组织免疫复合物沉积,臀肌小血管数目减少及管壁损伤。由此认为免疫病理因素是儿童臀肌挛缩症的主要发病机理。  相似文献   
1000.
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