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31.
Many viruses alter different stages of apoptosis of infected cells as a strategy for successful infection. Few studies have addressed mechanisms of equine herpesvirus 1 (EHV-1) strain-induced cell death. We investigated the effect of an abortigenic strain (AR8 strain) on heterologous Madin–Darby bovine kidney cells and homologous equine dermis (ED) cells cell lines. We compared morphologic and biochemical features of early and late apoptosis at different postinfection times. We investigated translocation of phosphatidylserine to the cell surface, nuclear fragmentation and changes in the cytoskeleton using flow cytometry and annexin V/propidium iodide staining, DNA laddering, terminal deoxynucleotidyl transferase UTP nick-end labeling assay and immunofluorescence staining of cytokeratin 18 cleavage. AR8 EVH-1 strain interfered with apoptosis in both cell lines, particularly during the middle stage of the replication cycle; this was more evident in ED cells. Although this antiapoptotic effect has been reported for other alpha herpesviruses, our findings may help elucidate how EHV-1 improves its infectivity during its cycle.  相似文献   
32.
Jailing of a side-branch is a known complication of stent implantation, and makes access to the side-branch difficult, especially if the stent is of the self-expanding type. Although plain balloon angioplasty is feasible for the jailed side-branches, the use of newer devices (a stent, Rotablation or atherectomy) has not been described. We describe a novel way of treating a side-branch jailed by a self-expanding stent by using stent implantation through the strut of a self-expanding stent.  相似文献   
33.
In order to test their value in urinary infection a double-blind trial was carried out using ampicillin, cephalexin, trimethoprim-sulphamethoxazole (co-trimoxazole), and trimethoprim. Eighty-three courses of treatment were given to hospital patients, 149 to pregnant women, and 107 to patients with dysuria and frequency seen in domiciliary practice. Thus infections of varying severity in defined groups of patients caused by organisms with different antibiotic sensitivities were treated.Analysis of the overall results (339 courses) was compared with those from the individual groups and considerable variation in response was found. In domiciliary infections and bacteriuria in pregnancy trimethoprim alone proved to be at least as effective as the other three compounds and caused fewer than half the number of side effects. In the hospital patients co-trimoxazole was superior to trimethoprim.The overall results for ampicillin and cephalexin were similar although cephalexin proved to be inferior in treating symptomatic domiciliary infections.  相似文献   
34.
Fissidens austro-americanus, from Brazil and Suriname, is described, illustrated, and its relationship toF. brevipes, F. ramicola, andF. leptophyllus discussed.  相似文献   
35.
36.

Background

Experimental studies support an important role for endothelial nitric oxide synthase (eNOS) in the regulation of angiogenesis. In humans, a common polymorphism exists in the eNOS gene that results in the conversion of glutamate to aspartate for codon 298. In vitro and in vivo studies have suggested a decreased NOS activity in patients with the Asp298 variant. We hypothesized that a genetic-mediated decreased eNOS activity may limit collateral development in patients with chronic coronary occlusions.

Methods

We selected 291 consecutive patients who underwent coronary angiography and who had at least one chronic (>15 days) total coronary occlusion. Collateral development was graded angiographically using two different methods: the collateral flow grade and the recipient filling grade. Genomic DNA was extracted from white blood cells and genotyping was performed using previously published techniques.

Results

Collateral development was lower in patients carrying the Asp298 variant than in Glu-Glu homozygotes (collateral flow grade: 2.64 ± 0.08 and 2.89 ± 0.08, respectively, p = 0.04; recipient filling grade: 3.00 ± 0.08 and 3.24 ± 0.07, respectively, p = 0.04). By multivariable analysis, three variables were independently associated with the collateral flow grade: female gender, smoking, and the Asp298 variant (p = 0.03) while the Asp298 variant was the sole variable independently associated with the recipient filling grade (p = 0.03).

Conclusion

Collateral development is lower in patients with the Asp298 variant. This may be explained by the decreased NOS activity in patients with the Asp298 variant. Further studies will have to determine whether increasing eNOS activity in humans is associated with coronary collateral development.  相似文献   
37.
Mass transfer rates in liquid-liquid extraction processes can be seriously affected by the presence of surface-active contaminants. This is especially true of applications of a biotechnological origin, where the microorganism used in the process may produce the surface-active contaminants. An investigation into the effects of soluble and insoluble fermentation broth components on mass transfer using chloramphenicol extraction into octanol as the model system was conducted. Soluble components produced during fermentation were found to adsorb to the interface, where they reduced the overall mass transfer coefficient by up to 70%. After fractionation it was found that components in the weight range from 10-30 kDa had the greatest effect on mass transfer. Protein and phospholipid compounds of similar size were found to reduce the overall mass transfer coefficient to a similar extent to the broth components at concentrations around 0.001mg/l. The biomass produced during the fermentation also reduced mass transfer substantially, and it is likely that this was due to physical blockage of the interface.  相似文献   
38.
Trimethoprim is inhibitory for a wide range of bacteria, and when used in combination with a sulphonamide marked synergy has been reported.In order to test its value in the treatment of urinary infections 154 hospital patients with infections of varying severity and due to a wide range of organisms were treated with combinations of sulphamethoxazole and trimethoprim. Combinations of these substances in two different ratios (2:1 and 10:1) were used in 113 patients, and one week after the end of treatment about three-quarters were cured by both combinations. In a second study 106 patients were treated with a sulphamethoxazole-trimethoprim combination (5:1), ampicillin, or sulphadimidine. The cure rate with the 5:1 combination was higher than that found with ampicillin or sulphadimidine both one week after finishing treatment (sulphamethoxazole-trimethoprim 85%, ampicillin 70%, sulphadimidine 40%) and at the fourth- to fifth-week follow-up (sulphamethoxazole-trimethoprim 67%, ampicillin 52%, sulphadimidine 15%).The results obtained with the various sulphamethoxazole–trimethoprim combinations did not indicate that a particular ratio was superior for treating urinary infections in general or for those caused by any particular species of organism.Laboratory studies showed that many bacteria causing urinary infections in hospital were sensitive to trimethoprim, and the therapeutic results could have been largely predicted from a knowledge of the in-vitro sensitivity tests to trimethoprim alone. For example, sulphamethoxazole–trimethoprim in the treatment of Proteus mirabilis infections was less successful than in those due to Escherichia coli, and this finding was clearly reflected in the higher minimal inhibitory concentrations for trimethoprim of Pr. mirabilis.The sulphamethoxazole–trimethoprim combination was simple to administer, free from side-effects, and gave satisfactory results in the treatment of urinary infections that occurred in hospital patients.  相似文献   
39.
Abstract The biochemical pathway and genetics of autotrophic ammonia oxidation have been studied almost exclusively in Nitrosomonas europaea. Terrestrial autotrophic ammonia-oxidizing bacteria (AAOs), however, comprise two distinct phylogenetic groups in the beta-Proteobacteria, the Nitrosomonas and Nitrosospira groups. Hybridization patterns were used to assess the potential of functional probes in non-PCR-based molecular analysis of natural AAO populations and their activity. The objective of this study was to obtain an overview of functional gene homologies by hybridizing probes derived from N. europaea gene sequences ranging in size from 0.45 to 4.5 kb, and labeled with 32P to Southern blots containing genomic DNA from four Nitrosospira representatives. Probes were specific for genes encoding ammonia monooxygenase (amoA and amoB), hydroxylamine oxidoreductase (hao), and cytochrome c-554 (hcy). These probes produced hybridization signals, at low stringency (30 degreesC), with DNA from each of the four representatives; signals at higher stringency (42 degreesC) were greatly reduced or absent. The hybridization signals at low stringency ranged from 20 to 76% of the total signal obtained with N. europaea DNA. These results indicate that all four functional genes in the ammonia oxidation pathway have diverged between the Nitrosomonas and Nitrosospira groups. The hao probe produced the most consistent hybridization intensities among the Nitrosospira representatives, suggesting that hao sequences would provide the best probes for non-PCR-based molecular analysis of terrestrial AAOs. Since N. europaea can also denitrify, an additional objective was to hybridize genomic DNA from AAOs with probes for Pseudomonas genes involved in denitrification. These probes were specific for genes encoding heme-type dissimilatory nitrite reductase (dNir), Cu-type dNir, and nitrous oxide reductase (nosz). No hybridization signals were observed from probes for the heme-type dNir or nosz, but Nitrosospira sp. NpAV and Nitrosolobus sp. 24-C hybridized, under low-stringency conditions, with the Cu-type dNir probe. These results indicate that AAOs may also differ in their mechanisms and capacities for denitrification.  相似文献   
40.
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