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101.
作者通过内窥镜对新疆奎屯地区氟中毒患者35名,氟砷中毒患者32名,对照组25名的胃粘膜进行观察,旨在了解氟元素和砷元素对胃粘膜的影响,在3个组中慢性胃炎的炎症程度与炎症活动性有显著性差异。2个中毒组间无显著性差异。结果表明在高氟区和高氟砷区患者的胃粘膜层病理改变主要是任性氟中毒引起,单纯性砷中毒并无协同作用。  相似文献   
102.
ATPase-stained normal and topical nitrogen mustard treated Langerhans cells (LC) in guinea pig epidermis were studied quantitatively and morphologically by computerized image analysis. Significant correlation and linear regression were found between the perimeter and square root of its area for both cytoplasm and nucleus; a theoretical basis was thus given for morphological identification of LC. The directly measured and derived geometric parameters indicated not only substantial alteration of cytoplasm morphology of post-treated LC such as cytoplasmatosis and dendrites reduction but also a potential change of nuclear size and functional status. We conclude that quantitative morphological analysis is an objective, precise and practical method for LC research.
  相似文献   
103.
本文应用L929细胞杀伤法,对注射旋毛虫肌肉期幼虫分泌物(L1ES)的小鼠血清进行了检测,发现L1ES对已注射卡介苗(BCG)或感染旋毛虫的小鼠,均能诱生肿瘤细胞毒因子(TCF),而正常对照鼠则不能发生,表明L1ES诱生TCF需要首先激活巨噬细胞(Mφ)这一基本条件。将L1ES置37℃、1h,56℃、30min或100℃、2min处理后,其诱生TCF的能力均明显高于对照组(P<0.05)。L1ES  相似文献   
104.
Pathways and enzymes of fatty acid synthase-mediated, long-even-chain (generally C16-C20) fatty acid synthesis are well studied, and general metabolism involved in short-chain (C4-C7) fatty acid biosynthesis is also understood. In contrast, mechanisms of medium-chain (C8-C14) fatty acid synthesis are unclear. Recent work suggests involvement of chain-elongation-terminating thioesterases in medium-chain fatty acid formation in oilseeds and animals. We have shown that iso- and anteiso-branched and straight, odd- and even-length, short-chain fatty acids esterified in plant-trichome-gland-produced sucrose esters are synthesized by using carbon skeletons provided by modified branched-chain amino acid metabolism/catabolism. The principal enzymes involved are those catalyzing leucine biosynthesis in all organisms and those leading to short-chain alcohols in mutant yeasts and alkyl acids in Clostridium species (products often serving as mammalian pheromones). Here we provide evidence that C10-C12 straight medium-chain and C10-C12 branched medium-chain acyl acids of tomato, C6-C8 straight-chain acyl acids of Petunia, and C6 and C8 branched acyl acids of Nicotiana glutinosa are formed by alpha-ketoacid elongation without participation of fatty acid synthase-mediated reactions or -independent thioesterases. This different metabolism suggests greater integration of amino acid and fatty acid metabolism than previously considered and provides other avenues to study and manipulate not only straight even-length but also odd- and even-length straight and branched medium-chain fatty acid biosynthesis.  相似文献   
105.
Dimethyll-curine dimethochloride was obtained by methylating the l-curine which was isolated from plants belonging to Genesia Cyclea widely distributed in Hainan Island, South China. It is a non-depolariz- ing post neuromuscular junctional blocker acting upon N2 receptor. Its chemical structural formula, physical properties, pharmacological actions and acute or chronic toxicities have been thoroughly studied. Its biological activities varied a great deal in different experimental animals but their clinical potency is uniform. Its activity is 51.8% as those of d-tubocura rine. Clinically, 1,449 cases, male and female, aged and young, were studied. Among them 422 were employed for endotracheal intubation, 468 for muscu Iar relaxation and 559 for both. Operation varied, including intracraneal, intra-abdominal and open heart surgery. Different kinds of anesthetics and adjuvants were used in association. I.V. dosage of 0.4-0.5 mg/kg or more was enough for intubation while 0.2-0.3 mg/kg for relaxation. Average duration of action was 30-40 minutes, but could be prolonged after heavy doses. Side effects were limited only to mild hypotension and temporal face freshness, while cardiovascular disturbances were very insig- nificant.  相似文献   
106.
采用两株分别带有不同抗药性标记的产黄青霉原生质体以1:1相混合,用30%的聚乙二醇(MW6000)原生质体融合处理。将混和物涂布在补给有两种药物同时存在的高渗性分离培养基上,培养后获得异核体菌落。洗下异核体分生孢于继续分离在补给有两种药物同时存在的分离培养基上,得到了同时带有两种抗性标记的重组体。纯化后,进行抗性稳定性和摇瓶效价的测定,将一株具有双重抗性、摇瓶发酵效价较高的菌株作出发菌株,经诱变因子处理后,获得了一株43u7c—57菌株,在摇瓶中效价比生产菌株平均提高4.94%,该菌株在40吨发酵罐试生产后,发酵效价平均提高4.4%,产量则平均增加12.15%。  相似文献   
107.
CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.  相似文献   
108.
提要报告了55例儿童桡骨骨折,观察发现该病挠骨头变位情况并不完全一致,据此提了分为外侧型、外后侧型和外前侧型3型的新的分型方法。采用相应整复手法,提高了复位满意率。本组优良率达85%,其中外侧型复位较易,优良率为93%;外后侧型次之;外前侧型复位困难,优良率为70%。  相似文献   
109.
110.
温州市农村贫困人群卫生服务需求和利用分析   总被引:2,自引:0,他引:2  
通过对近2000份调查表的分析,评价温州市农村贫困人群在就诊过程中对医疗机构的选择、未就诊原因方面的特点,提出提高卫生服务利用的方法。  相似文献   
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