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61.
Vroman  L; Adams  AL; Fischer  GC; Munoz  PC 《Blood》1980,55(1):156-159
Using ellipsometry, anodized tantalum interference color, and Coomassie blue staining in conjunction with immunologic identification of proteins adsorbed at interfaces, we have previously found that fibrinogen is the main constituent deposited by plasma onto many man- made surfaces. However, the fibrinogen deposited from normal plasma onto glass and similar wettable materials is rapidly modified during contact activation until it can no longer be identified antigenically. In earlier publications, we have called this modification of the fibrinogen layer "conversion," to indicate a process of unknown nature. Conversion of adsorbed fibrinogen by the plasma was not accompanied by marked change in film thickness, so that we presumed that this fibrinogen was not covered but replaced by other protein. Conversion is now showen to be markedly delayed in plasma lacking high molecular weight kininogen, slightly delayed in plasma lacking factor XII, and normal in plasma that lack factor XI or prekallikrein. We conclude that intact plasma will quickly replace the fibrinogen it has deposited on glass-like surfaces by high molecular weight kininogen and, to a smaller extent, by factor XII. Platelets adhere preferentially to fibrinogen-coated surfaces; human platelets adhere to hydrophobic nonactivating surfaces, since on these, adsorbed firbinogen is not exchanged by the plasma. The adsorbed fibrinogen will be replaced on glass-like surfaces during surface activation of clotting, and platelets failing to find fibrinogen will not adhere.  相似文献   
62.
We assessed the prevalence and predictors of latent Toxoplasma infection in a large group of human immunodeficiency virus (HIV)-infected and HIV-uninfected at-risk US women. The prevalence of latent Toxoplasma infection was 15% (380 of 2525 persons) and did not differ by HIV infection status. HIV-infected women aged > or =50 years and those born outside of the United States were more likely to have latent Toxoplasma infection, with prevalences of 32% and 41%, respectively.  相似文献   
63.
BACKGROUND & AIMS: Constitutive expression of cyclooxygenase 2 (COX-2) has been found in 85% of colorectal cancers. Ras mutations are found in 50% of colorectal adenocarcinomas. The aim of this study was to determine the role of COX-2 in ras-induced transformation in rat intestinal epithelial (RIE) cells. METHODS: Cell growth was determined by cell counts. The expression of COX-2 was examined by Northern and Western analyses. For tumorigenicity assays, cells were inoculated into dorsal subcutaneous tissue of athymic nude mice. DNA-fragmentation assays were performed to detect apoptosis. RESULTS: The expression of COX-2 was increased in RIE-Ras cells at both messenger RNA (9-fold) and protein (12-fold) levels. Prostaglandin I2 levels were elevated 2.15-fold in RIE-Ras cells. Serum deprivation further increased COX-2 expression 3.8-fold in RIE-Ras cells. Treatment with a selective COX-2 antagonist (SC58125) inhibited the growth of RIE-Ras cells through inhibition of cell proliferation and by induction of apoptosis. SC-58125 treatment reduced the colony formation in Matrigel by 83.0%. Intraperitoneal administration of SC-58125 suppressed RIE-Ras tumor growth in nude mice by 60.3% in 4 weeks. SC-58125 treatment also induced apoptosis in RIE-Ras cells as indicated by increased DNA fragmentation. CONCLUSIONS: Overexpression of COX-2 may contribute to tumorigenicity of ras-transformed intestinal epithelial cells. Selective inhibition of COX-2 activity inhibits growth of ras-transformed intestinal epithelial cells and induces apoptosis. (Gastroenterology 1997 Dec;113(6):1883-91)  相似文献   
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Properties of a new potent antagonist acting selectively at N-methyl-D-aspartate (NMDA) type excitatory amino acid receptors are described. This compound, 3-((+/-)-2-carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP) is more potent than all previously reported NMDA antagonists in depressing mammalian spinal neuronal responses (cat and immature rat), in its affinity for [3H]D-AP5 (a radiolabelled NMDA antagonist) binding sites on rat brain membranes, and as an anticonvulsant in mice.  相似文献   
67.
Hepatic spiral CT: reduction of dose of intravenous contrast material   总被引:13,自引:0,他引:13  
  相似文献   
68.
目的尿液沉渣分析红、白细胞由传统的定性报告方式改为定量分析(××/μl).由于使用的检查方法不同,其参考值也不一样,国内目前尚未有统一的参考值,为使牡丹江市有一个统一的判断标准.方法我们对1109名健康成人其中男性591人,女性518人进行尿中红细胞及白细胞的参考值调查.方法采用国内的专用尿沉渣计数板,显微镜下计数.对体检者在统一时间清晨7点钟留取尿液20~30毫升,按统一操作规程进行操作,对不同性别的人群进行参考值的调查.结果男性红细胞x是1.12,S是1.42,95%可信界限0~3.96,参考值范围0~4/μl;男性白细胞x是1.84,是S 2.05,95%可信界限0~5.94,参考值范围0~6/μl.女性红细胞x是2.46,S是3.26,95%可信界限0~8.98,参考值范围0~9/μl;女性白细胞x是2.25,S是3.82,95%可信界限0~9.89,参考值范围0~10/μl.结论通过1109名正常成人尿液红细胞及白细胞含量的调查,建立了牡丹江市的参考值.  相似文献   
69.
Ambulatory sclerotherapy for malignant pleural effusions   总被引:12,自引:0,他引:12  
  相似文献   
70.
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