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71.
在标记脐血造血祖细胞表面抗原(HPCA),CD34中,比较抗-HPCA-2-FITC和Tk3(纯抗体)标记的CD(34+)细胞在流式细胞仪分析中的荧光特征及两种单抗标记的CD(34+)细胞与体外培养的粒单细胞集落形成单位(CFU-GM),红系爆发形成单位(BFU-E),和混合集落形成单位(CFU-Mix)的相关性。结果发现脐血有核细胞中,抗HPCA-2阳性细胞占1.05±0.72%(n=13),Tk3阳性细胞占2.06±1.25%(n=8),差别显著(P<0.05)。每毫升脐血两种抗体标记的细胞分别为96.56±56.64和231.40±163.93(P<0.05)。尽管HPCA-2阳性细胞与Tk3阳性细胞数量呈显著正相关(r=0.875,P<0.01),前者与CFU-GM,BFUE,CFU-Mix及集落总数CFUs均呈正相关,而后者仅与CFU-GM,CFUs相关。研究提示在检测造血祖细胞时,用抗-HPCA-2-FITC代替Tk3可降低假阳性,获得较好的OD(34+)细胞与CFU间的线性关系。 相似文献
72.
用结合^131碘和化疗药物的明胶微球作肝动脉... 总被引:1,自引:0,他引:1
Nine patients with inoperable hepatoma were treated by using hepatic arterial embolization 131I and chemotherapeutic agent gelatin microsphere (131I-CA-GM). The emission CT after operation detected that the microspheres were concentrated on tumor area. The ratio between the radioactivity in tumor and that in liver was 4.1:1. A case died of ictopic embolization; the others survived 3, 4, 5, 19, 24, 7, 8, and 12 months respectively. Three of them were still alive. 131I-CA-GM has triple anticarcinogenic actions, including the arterial occlusion, targeting chemotherapy and internal radiation. The microspheres can selectively accumulate in the tumor artery and can be easily traced by gamma-camera or emission CT. 131I-CA-GM is a hopeful embolic agent for the treatment of liver cancer, but some problems about ectopic arterial embolization should be further studied. 相似文献
73.
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
74.
旋毛虫幼虫分泌物抗原在小鼠体内诱生肿瘤细胞毒因子的研究 总被引:6,自引:0,他引:6
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
75.
A pathway for the biosynthesis of straight and branched, odd- and even-length, medium-chain fatty acids in plants. 总被引:2,自引:0,他引:2 下载免费PDF全文
A B Kroumova Z Xie G J Wagner 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(24):11437-11441
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
76.
Wu Jue吴珏Department of Anesthesiologlj Shanghai Medical University ShanghaiXie Fu-sheng谢福生Teaching Hospital Guangzhou College of Traditional Chinese Medicine Guangzhou 《中华医学杂志(英文版)》1987,100(3):173-176
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
77.
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
78.
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
79.
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
80.
中药“425”对血吸虫卵肉芽肿病变免疫调节作用的机理研究 总被引:4,自引:1,他引:3
本文试验结果发现,应用“425”制剂可明显增强宿主脾细胞在体外自发性的及在LPS刺激下的增生反应,明显抑制其在PHA刺激下的增生反应,而用药后宿主脾细胞在特异性抗原刺激下的增生反应未见明显改变;虽然用药组感染鼠的脾脏明显小于对照组,但血清及虫卵肉芽肿培养上清中特异性抗体IgG水平未见明显改变。研究结果表明,“425”制剂具有双重非特异性免疫调节作用。该制剂抑制宿主肝组织内虫卵肉芽肿病变的机理除了在于其能非特异地增强宿主B细胞介导的体液免疫应答外,该制剂对宿主体内T细胞介导的细胞免疫应答的非特异性抑制作用可能起了更重要的作用。 相似文献