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41.
建立红花油乳液的生产质量控制条件。方法:检测乳滴大小、离心效果及卫生学指标变化。结果:在640倍显微镜下观察,红花油乳滴直径小于5μm;使用高速离心机,以4000r/min离心10min后无明显分层,若有少许分层但振摇后立即恢复均相;卫生学符合国家标准。  相似文献   
42.
We surveyed and assessed 2,323 schoolchildren aged seven to 17 years from four schools in China, two in the city of Tianjin and the other two in a neighbouring rural village, Ban Chau, to investigate the prevalence of refractive error and its relationship with environmental factors. Every child from each of the participating classes was recruited in this study to avoid self-selection. A questionnaire was issued which queried some aspects of the child's visual habits and home. Refraction was canied out using the Canon R-22 autorefractor. The degree and frequency of myopia in these children increased almost linearly from age seven to 17 years. There was little difference between the urban and rural groups. Of the factors explored, the number of hours spent on near work showed the best correlation with the degree of myopia, albeit only weakly.  相似文献   
43.
维拉帕米增强博莱霉素A5抗癌活性的机制   总被引:2,自引:0,他引:2  
本文利用流式细胞术(FCM)和动物整体水平的同位素标记药物示踪方法探讨了维拉帕米(VP)增强博莱霉素A5(BLM)抗癌活性的机制。实验发现VP显著增强BLM对S-180和HEP-2细胞的G2期阻断效应。VP改变了57Co-BLM在荷瘤小鼠部分器官中的分布,增加厂该药在肿瘤中的积聚。VP增強BLM抗癌活性可能是通过增加药物在肿瘤中的积聚,增强药物的G2期阻断效应以及其它作用实现的。  相似文献   
44.
Factor V Leiden mutation in one family of Chinese origin   总被引:1,自引:0,他引:1  
Objective To investigate the factor V Leiden mutation associated with activated protein C resistance (APCR) in Chinese. Methods Thirty “normal' individuals and twenty patients with thrombotic disease from Chinese Han Nationality were studied with APTT±APC, PCR followed by MnLI restriction enzyme analysis,PCR based direct sequence-specific primers (PCR-SSP) and DNA sequence analysis. Results In one healthy control, the activated protein C (APC) sensitivity ratio (SR) was found to be significantly lower (0.8) than that in other normal control (>2.0). This individual was identified to be heterozygous for FV Leiden mutaiton (Arg506-Gln). His grand-uncle, father, brother and son were also identified to be heterozygous for FV Leiden. The APC resistance was found in 3 other cases of thrombotice diseases, but with no FV Leiden mutation. Conclusion This is the first four generations family case of FV Leiden mutation associated with APCR reported within Chinese ethnic population. It is note-worthy that more FV Leiden or whether other gene defects may be associated with APC resistance and acquired APCR causing thrombosis in Chinese population.  相似文献   
45.
46.
We have studied the modifications in the multimeric composition of plasma factor VIII/von Willebrand factor and the bleeding time response following administration of 1-Deamino-[8-D-arginine]-Vasopressin (DDAVP) to patients with different subtypes of von Willebrand's disease. In type I, all multimers were present in plasma in the resting state, though they were decreased in concentration. Administration of DDAVP resulted in an increased concentration of these forms as well as the appearance of larger forms than were previously present. There was concomitant correction of the bleeding time. In type IIA, large multimers were absent in the resting state, and although DDAVP induced an average threefold increase in the plasma concentration of factor VIII/von Willebrand factor, the larger multimers did not appear and the bleeding time, although shortened, was not corrected. In contrast, the larger multimers that were also absent from type IIB plasma in the resting state rapidly appeared following DDAVP administration. However, their appearance was transitory and the bleeding time, as in IIA patients, was shortened but not corrected. The characteristic multimeric composition of platelet factor VIII/von Willebrand factor in given subtypes predicted the alteration in plasma factor VIII/von Willebrand factor induced by DDAVP. These studies provide evidence that the different subtypes of von Willebrand's disease represent distinct abnormalities of factor VIII/von Willebrand factor. They also suggest that complete hemostatic correction following DDAVP can be routinely expected only in type I von Willebrand's disease, and only if factor VIII/von Willebrand factor can be raised to normal levels.  相似文献   
47.
48.
Budde  U; Dent  JA; Berkowitz  SD; Ruggeri  ZM; Zimmerman  TS 《Blood》1986,68(6):1213-1217
In order to evaluate the role of proteolysis in acquired von Willebrand's disease (vWD) associated with the myeloproliferative syndrome, we have determined the relative quantity of von Willebrand factor (vWF) fragments as compared with the intact 225 kDa subunit in four patients. The plasma vWF of each individual lacked large multimers; each had a prolonged bleeding time; and both platelet and leukocyte counts were elevated. Plasma was obtained from blood drawn into 1 mmol/L leupeptin, 6 mmol/L N-ethylmaleimide, and 5 mmol/L EDTA to prevent in vitro proteolysis. vWF was isolated from plasma by immunoadsorbent chromatography, reduced, subjected to SDS-5% polyacrylamide gel electrophoresis, and immunoblotted with a mixture of 55 anti-vWF monoclonal antibodies. In three patients with essential thrombocytosis (ET) the 176 and 140 kDa fragments were increased in proportion to the intact 225 kDa subunit indicating increased proteolysis. Treatment of one ET patient with CCNU (Lomustine) decreased the platelet count and, to a lesser extent, the white blood cell count. This was associated with a correction of the bleeding time, a partial correction of the multimeric abnormality, and a lessening of vWF cleavage. In a patient with polycythemia rubra vera (PRV) the proportion of the 176 kDa fragment was increased to the upper limit of normal but there was no definite evidence of increased proteolysis. These studies provide evidence that proteolysis plays a role in the acquired von Willebrand's disease associated with the myeloproliferative syndrome. However, other mechanisms must also be considered.  相似文献   
49.
Kulkarni  SS; Wang  ZM; Spitzer  G; Taha  M; Hamada  H; Tsuruo  T; Dicke  KA 《Blood》1989,74(6):2244-2251
The effectiveness of ex vivo chemotherapy with drugs, such as vincristine, etoposide, and Adriamycin (doxorubicin, Adria Labs, Columbus, OH) for elimination of residual tumor cells from human bone marrow grafts could be undermined by the presence of multidrug- resistant tumor cells in the bone marrow. Therefore, to supplement chemoseparation, we investigated whether MRK-16, a monoclonal antibody (MoAb) to the surface moiety of multidrug resistance-associated P- glycoprotein antigen, can eliminate drug-resistant tumor cells in the presence of rabbit complement (RC). Two doxorubicin (DOX)-resistant human myeloma tumor cell line, 8226/DOX40 (resistant to 4 x 10(-7) mol/L DOX) and 8226/DOX6 (6 x 10(-8) mol/L DOX) with high and low amounts of cell surface P-glycoprotein, respectively, and the drug- sensitive parent cell line 8226/S were used as tumor models in this study. Using the limiting dilution assay, we have shown that three cycles of treatment with 25 micrograms/mL of MRK-16 MoAb and a 1:4 final dilution of RC eliminated 2.90 +/- 0.10 logs of 8226/DOX40 cells and 1.94 +/- 0.18 logs of 8226/DOX6 cells. One and two cycles of treatment were less effective, eliminating 0.47 +/- 0.40 and 1.94 +/- 0.36 logs of 8226/DOX40 and 0.12 +/- 0.20 and 1.63 +/- 0.58 logs of 8226/DOX6 cells, respectively. The 8226/S cell growth was unaffected by one to three cycles of treatment. The cell kill was not impaired when the antibody plus complement treatment was carried out on a mixture of 8226/DOX40 or 8226/DOX6 cells with a ninefold excess of irradiated bone marrow mononuclear cells (MNCs). The three cycles of treatment with antibody plus complement did not adversely affect granulocyte- macrophage colony-forming unit (GM-CFU) survival in hematologically normal marrows (92.5% to 104% survival) or in myeloma patient marrows (85% to 100%). These results show that it is possible to eliminate drug- resistant myeloma tumor cell lines from the admixed human bone marrow by treatment with MRK-16 MoAb plus RC. This method could prove to be effective for elimination of other drug-resistant tumor cell lines including those of leukemia and solid tumors, and will be further useful for supplementing chemopurging, and immunopurging of bone marrow with other antitumor cell antibodies.  相似文献   
50.
国产阿克拉霉素A(aclacinomycin;ACM-A)能明显抑制体外培养小鼠白血病P388和人体胃癌SGC-7901细胞的生长。在0.01 μg/ml浓度时能抑制65.4%的克隆形成,ED50为0.0085μg/ml。ACM-A对白血病小鼠有显著治疗作用,延长小鼠生命时间143%,并有半数小鼠获得治疗。对Ehrlich腹水癌和肉瘤-180也有较强的抑制作用,对肉瘤-180的作用与adriamycin相似。ACM-A主要抑制3H-TDR和。H-UR分别参人人体胃癌细胞的DNA和RNA;大剂量时对蛋白质合成也有影响。P388细胞实验中证明ACM-A对DNA合成的抑制程度与adriamycin相似,低于daunomycin。  相似文献   
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