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21.
Characterization of the effects of cultured vascular cells on the activation of blood coagulation 总被引:9,自引:0,他引:9
The coagulant properties of intact bovine vascular cells (aortic endothelial and smooth muscle cells) and human vascular cells (cutaneous and foreskin microvascular cells, umbilical venous endothelium) grown in vitro were studied. Compared to nonvascular cells (fibroblasts, corneal endothelial cells, fetal lung or intestinal mucosal cells), vascular cells had little procoagulant activity. Radioimmunologic measurement of thrombin in recalcified plasma demonstrated markedly lower concentrations of thrombin in the presence of vascular endothelial and smooth muscle cells compared to corneal endothelial and fetal lung cells. The low thrombin concentrations were not a consequence of thrombin binding to the vascular cells nor were they due to accelerated thrombin inactivation by antithrombin-III or alpha 2-macroglobulin. Neither vascular cells nor the nonvascular cells promoted contact activation of plasma as measured by a sensitive specific assay for kallikrein. Studies with intact cell monolayers and purified factors VIIa and X indicated that while nonvascular cells express tissue factor activity, vascular cells do not exhibit this property. These data suggest that the nonthrombogenic nature of intact vascular cells is due to their failure to initiate contact activation and to express tissue factor activity. In addition, the primary difference in coagulant potential between vascular cells and nonvascular cells is the lack of tissue factor expression by the vascular cells. 相似文献
22.
贵池日本血吸虫对江苏沿海地区钉螺感染性的初步研究 总被引:1,自引:1,他引:1
目的 了解异地血吸虫品系对江苏省沿海残存钉螺的感染性。方法 用安徽省贵池现场感染性钉螺逸出的尾蚴感染家兔所取得的毛蚴 ,以毛蚴与钉螺 2 0∶ 1感染现场采集的钉螺 ,比较钉螺感染率和尾蚴逸出前期。结果 贵池血吸虫对如东、东台和贵池 3地钉螺感染率分别为 4 .35 %、16 .0 0 %和 4 0 .5 8% ,尾蚴平均逸出前期分别为 (72 .6 9± 8.73) d、(6 8.35± 5 .78) d和 (71.5 0± 9.0 7)d,贵池血吸虫对当地钉螺感染率显著高于对江苏沿海钉螺的感染率 (x1 2 =2 4 .5 8,x2 2 =14 .35 ,P <0 .0 1) ,尾蚴逸出前期差异无显著性 (t1 =0 .0 2 35 ,t2 =0 .1732 ,P>0 .1)。结论 江苏沿海地区钉螺在室内能被贵池血吸虫实验感染 ,长江流域血吸虫的输入 ,有可能导致血吸虫病的再流行 相似文献
23.
Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients. 相似文献
24.
PG Kareru JM Keriko GM Kenji GT Thiong'o AN Gachanja HN Mukiira 《African journal of traditional, complementary, and alternative medicines》2010,7(3):214-218
In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus. 相似文献
25.
目的:分析血管紧张素原基因启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性。方法:实验于2005-08/2006-01在北京华大实验室完成。选取对象均为生活在内蒙古乌拉特后旗的蒙古族牧民,三代血亲内无其他民族。采用基因测序技术对内蒙古蒙古族人群中107例原发性高血压患者和108例正常对照者进行A-20C和A-6G基因分型,观察高血压组和正常对照组不同基因型的分布和等位基因频率的差异。结果:①两组受试者在性别、年龄及吸烟、饮酒、体质量指数和临床化验检查指标有较好的匹配(P均>0.05)。②两组血管紧张素原基因A-20C位点AA,AC,CC基因型频率比较差异无显著性意义(高血压组分别为0.51,0.29,0.20;正常对照组分别为0.49,0.28,0.23,χ2=0.395,P=0.529)。A,C等位基因频率比较差异无显著性意义(高血压组分别为0.65,0.35;正常对照组分别为0.63,0.37,χ2=0.015,P=0.904)。③两组血管紧张素原基因A-6G位点AA,AG,GG基因型频率比较差异无显著性意义(高血压组分别为0.50,0.33,0.17;正常对照组分别为0.55,0.34,0.11,χ2=1.924,P=0.165)。A,G等位基因频率比较差异无显著性意义(高血压组分别为0.66,0.34;正常对照组分别为0.72,0.28,χ2=1.728,P=0.189)。④高血压组协同存在血管紧张素原基因A-20C基因型CC时,血管紧张素原基因A-6G基因型GG频率稍高于正常对照组,但差异无显著性意义(χ2=2.395,P=0.122,OR=7.52,95%CI0.014~1.250),高血压组G等位基因明显高于正常对照组(分别为0.37,0.22,χ2=4.658,P=0.034),携带该等位基因的蒙古族人群发生原发性高血压的相对危险度升高(OR=2.80,95%CI1.087~7.271)。结论:血管紧张素原基因A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压相关,并可能具有协同作用。 相似文献
26.
KI Wheeler GM Schmölzer CJ Morley PG Davis 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(1):67-70
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency. 相似文献
27.
28.
José GM Hofhuis Henk F van Stel Augustinus JP Schrijvers Johannes H Rommes Jan Bakker Peter E Spronk 《Critical care (London, England)》2009,13(1):118-3
During recent years increasing attention has been given to the quality of survival in critical care. Health-related quality
of life (HRQOL) is an important issue both for patients and their families. Furthermore, admission to the intensive care unit
can have adverse psychological effects in critically ill patients. Recent studies conducted in critically ill patients have
measured HRQOL. However, usually absent from such reports are evaluations of conceptual issues, addressing factors such as
why HRQOL should be measured in critically ill patients, how to define and standardize domains of HRQOL, whether proxies can
provide useful information about HRQOL in critically ill patients, whether response shift occurs in critically ill patients,
and whether post-traumatic stress disorder (PTSD) occurs in critically ill patients. Some studies reported moderate agreement
between patients and their proxies, although lower levels of agreement may be reported for psychosocial or physical functioning.
Response shift (adaptation and change in perception) appears to be an important phenomenon and likely to be present, but it
is seldom measured when estimating HRQOL in critically ill patients. Furthermore, vigilance for symptoms of PTSD and early
interventions to prevent PTSD are needed. 相似文献
29.
Jack X Yu Anieta M Sieuwerts Yi Zhang John WM Martens Marcel Smid Jan GM Klijn Yixin Wang John A Foekens 《BMC cancer》2007,7(1):182
Background
Published prognostic gene signatures in breast cancer have few genes in common. Here we provide a rationale for this observation by studying the prognostic power and the underlying biological pathways of different gene signatures. 相似文献30.
A Ross GM Raab J Mok S Gilkison B Hamilton FD Johnstone 《Archives of disease in childhood》1995,73(6):490-495
OBJECTIVE: To determine the separate effects of maternal HIV infection and drug use during pregnancy on growth of uninfected children in their first 3 years. DESIGN: Retrospective analysis of measurements from health visitor records made during routine child health surveillance at 6 weeks, 10 months, and 3 years of age. Multilevel analysis allowed for between-infant variation in fitted growth lines, and adjustment for other factors. Growth was described in terms of an intercept (z score at term) and growth slopes (change in z score per year) up to, and from, 4 months. SUBJECTS: 290 case babies delivered in Edinburgh hospitals to women who reported injection drug use by either themselves or their HIV infected partner, and 186 community controls. A total of 131 (45%) of the case babies were born to women who used drugs, predominantly opiates, during pregnancy and 93 (32%) to HIV infected women. The eight infected children were excluded from analysis. MAIN OUTCOME MEASURES: Age and sex standardised z scores for height, weight, and body mass index. RESULTS: 459 (96%) of the 476 records for cases and controls were traced, yielding 1432 weight and 939 height measurements. Maternal HIV infection was not found to affect growth; at 3 years the estimated effect on weight z score was 0.16 with 95% confidence interval (-0.25 to 0.57) and for height 0.18 (-0.19 to 0.55). Drug use during pregnancy was associated with lighter babies at 40 weeks followed by depressed growth in the first four months, these infants remaining just slightly smaller at 3 years with an estimated effect on z scores of -0.5 for weight with 95% confidence interval (-0.89 to -0.11) and -0.37 (-0.72 to -0.02) for height. CONCLUSIONS: Maternal HIV infection does not adversely affect growth in uninfected infants, and the effect of drug use during pregnancy is limited to small decrease in size at 3 years. 相似文献