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排序方式: 共有482条查询结果,搜索用时 15 毫秒
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Marjan Boerma Gregory R Burton Junru Wang Louis M Fink Robert E McGehee Martin Hauer-Jensen 《Blood coagulation & fibrinolysis》2006,17(3):173-180
Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as well as after treatment with atorvastatin. It is necessary, however, to carefully select and validate changes in genes that are the focus of studies when using EA.hy926 cells. While this cell line is highly useful in studies on some genes, including genes encoding molecules involved in regulating thrombohemorrhagic homeostasis, they appear to be less suited for studies focused on other genes, particularly those involved in the regulation of cell proliferation and apoptosis. 相似文献
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In vitro and in vivo precipitation of iodinated contrast agents when ioxaglate and papaverine are given together has been reported. To verify these reports and to investigate other medications not previously tested, the authors analyzed mixtures of contrast agents and medications in vitro with a light spectrophotometer and observed them for visible precipitates for up to 120 minutes. Previously reported incompatibilities between ionic or low-osmolality contrast media and medications were verified, and several new incompatibilities were discovered. No incompatibilities were found when the drugs tested were mixed with the new nonionic contrast media. 相似文献
6.
Sequential contrast-enhanced MR imaging of the penis 总被引:1,自引:0,他引:1
7.
Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan 总被引:2,自引:0,他引:2
B Herrmann MAM Salih BE Yousif O Abdelwahab P-A Mårdh 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):169-172
The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies. 相似文献
8.
P. VON DEN DRIESCH C. STEFFAN A. ZÖBE O.P. HORNSTEIN 《Clinical and experimental dermatology》1994,19(3):274-277
We report the case of a 39-year-old female patient suffering from Sweet's syndrome after an upper respiratory tract infection. Cyclosporin A at a dose of 10 mg/kg per day was given as initial treatment. Skin lesions and general malaise resolved within 9 days. The cyclosporin dose was decreased within 21 days, without recurrence of the eruption. Cyclosporin is a potent inhibitor of T lymphocytes, but affects granulocyte and monocyte functions as well. Success of treatment in our case shows that cyclosporin represents an alternative to steroid treatment in patients with Sweet's syndrome. 相似文献
9.
Steve H Murdock Md Nazrul Hoque Kenneth Johnson Mary A McGehee 《The Journal of rural health》2003,19(4):425-432
The diversification of the rural population of the United States provides substantial challenges to the current and to future health care systems in rural areas. Because of a variety of historical, discriminatory, and other factors, minority populations have had lower levels of access to health care in rural as well as urban areas and higher rates of both mortality and morbidity than nonminority populations. Although minority health issues have often been seen as primarily urban issues, this article demonstrates that minority population growth has become a major component of total population growth in rural areas in the past several decades (accounting for nearly 62% of the net growth in the nonmetropolitan population of the United States in the 1980s and for nearly 42% in the 1990s), that future US population growth is likely to be largely a product of minority population growth (nearly 89% of US net population growth from 2000 to 2100 is projected to be due to minority population growth), and that the incidence of diseases and disorders in the US population will come to increasingly involve minority populations (by 2050 roughly 43% of all disease/disorder incidences would involve minority population members). The growth of younger minority populations with disproportionately impoverished socioeconomic characteristics will pose challenges for rural areas and health care systems, which also are likely to face health issues created by disproportionately older populations. 相似文献
10.
Dynamic particle image velocimetry (PIV) was applied to the study of the flow field associated with prosthetic heart valves.
The results were compared with those of laser Doppler anemometry (LDA). Anatomically and antianatomically oriented Jyros (JR)
and St. Jude Medical (SJM) valves were compared in the mitral position to study the effects of valve design on the downstream
flow field. The experimental program used a dynamic PIV system utilizing high-speed, high-resolution video to map the true
time-resolved velocity field inside the simulated ventricle. This system was complemented by a study using the more traditional
LDA system for comparison. Based on the experimental data, the following general conclusions can be made. High-resolution
dynamic PIV can capture true chronological changes in the velocity and turbulence fields. It also produces very detailed velocity
and turbulence information comparable to the LDA results. In the vertical measuring plane that passes both the center of the
aortic and mitral valves (A-A section), the two valves (the SJM and the JR) show distinct circulatory flow patterns when the
valve is installed in the antianatomical orientation. Small differences in valve design can generate noticeable differences,
particularly during the accelerating flow phase. The SJM valve maintains a relatively high velocity through the central orifice;
the curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow
phases. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where
characteristic differences in valve design will be visible, symmetrical twin circulations were observed because of the divergent
nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation. The SJM valve, with
a central downward flow near the valve, is contrasted with the JR valve, which has a peripheral downward circulation with
higher, turbulent stresses. 相似文献