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31.
Hypostomus sp 3-Córrego Salobrinha NUP 4247 and Hypostomus sp 2-Rio Perdido NUP 4249, collected in the Planalto da Bodoquena, Paraguay River basin, Brazil, were characterized cytogenetically. Hypostomus sp 3-Córrego Salobrinha showed two modal numbers. This polymorphism consists of the presence of two extrachromosomes. It was not possible to define the diploid number in four specimens, where cell lineages had 2n = 83 and 2n = 84 chromosomes in one individual, and 2n = 82, 2n = 83 and 2n = 84 chromosomes in the others. These results reveal the existence of a genetic mosaic due to the occurrence of one or two extrachromosomes in this species. Hypostomus sp 2-Rio Perdido NUP 4249 showed a 2n = 84, FN = 106 with size heteromorphism in one pair of chromosomes stained with AgNO3. In both species, C banding showed a pattern of heterochromatin distribution with a few small bands in the centromeric and pericentromeric regions coinciding with chromomycin A3 staining. Until now, the major diploid number for the genus Hypostomus was 2n = 80, but the species studied here had chromosomes that in creased this number and the variation for this genus. Our results are also the first cytogenetic data on Hypostomus from the Paraguay River basin.  相似文献   
32.
Given that signal sequences between secreted proteins of different species can be interchanged, it is reasonable to expect that both mammalian and yeast signal sequence trapping (SST) systems would secrete Haemonchus contortus proteins with similar efficiency and quality. To determine if H. contortus cDNAs that contain a signal sequence could re-establish secretion of a reporter protein, mammalian and yeast SST vectors were designed, 10 H. contortus genes selected, and their respective cDNAs cloned into these two SST vectors. The selected molecules included genes known to code for excretory/secretory or membrane-bound proteins as potential test 'positives', and genes known to code for non-secreted proteins as test 'negatives'. While differentiation between secretion and non-secretion was evident in both systems, the results indicated greater efficiency was achieved when the mammalian system was used. Therefore, mammalian SST using COS cells would be a more useful tool to screen H. contortus cDNA libraries for potential secreted and type-1 integral membrane proteins than yeast SST.  相似文献   
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 The adoptive transfer of in vitro generated tumor-specific cytotoxic T lymphocytes (CTL) is considered a promising perspective in cancer therapy. One possible drawback lies in the inappropriate homing of in vitro cultured lymphocytes, which could be circumvented by introducing the appropriate targeting molecules. Here we describe a protocol that allows a rapid and stable transfection of cytotoxic T cell clones. As a model system we used a CTL clone specific for the melanoma-associated antigen gp100 and a cDNA encoding for murine CD14 containing the variant exen v10 which is supposed to facilitate lymphocyte homing towards the skin. CD44v10 cDNA was ligated into the retroviral vector pMV-7, which was used to transfect the ecotropic GP-E-86 and the amphotropic PA317 cells. After several cycles of transduction to increase the viral titre, supernatants of the amphotropic PA317-CD44v10 line were used for transduction of CD44v10 into a human CTL clone. After three cycles of transduction at 12-h intervals, low but stable expression of CD44v10 was observed throughout the culture period of 10 weeks. The phenotype of the transduced CTL clone was unaltered and the cytotoxic potential was only slightly reduced as compared to the parental clone. The efficiency of stable transduction within a period of 1 week makes the protocol well suited for the in vivo transfer of transduced cells and, in the special case, should guarantee appropriate homing of the transduced CTL clone. Received: 14 August 1997 / Accepted: 20 November 1997  相似文献   
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The products of the microbial activity in the large intestine are an important source of energy for herbivores. A previous study showed differences in caecal methanogenesis and short-chain fatty acid (SCFA) profiles between brown hares and domestic rabbits. The present study was performed on animals which were offered the same diet to eliminate the impact of diet on the comparative analyses of microbial metabolites. Caecal samples of hares and rabbits were incubated in triplicate, i.e. without any supplementary substrate (control) or with the addition of wheat bran or oat bran. Calculated as percentage of body weight, the stomachs of the rabbits were heavier than those of the hares, but caeca of the hares weighed more than those of the rabbits. The total SCFA concentration in caecal samples was higher in rabbits than in hares, and it increased in both species when the supplementary fermentation substrates were added. In hares, the molar proportion of propionate was higher and that of butyrate was lower compared to rabbits. The addition of substrate decreased acetate and propionate but increased the molar proportion of butyrate. Microbial fermentation resulted in greater gas release in rabbit caecal samples compared to those of hares. Methanogenesis tended to be lower in hares than in rabbits, but high individual variability was observed, especially in hares. Our study stated lower microbial activity in the caeca of brown hares compared to domestic rabbits. The presented results might lead to assumption that differences between fermentation patterns were not caused by diet but resulted from the peculiarities of both species.  相似文献   
37.
BackgroundIntegration of HIV services with other health services has been proposed as an important strategy to boost the sustainability of the global HIV response. We conducted a systematic and comprehensive synthesis of the existing scientific evidence on the impact of service integration on the HIV care cascade, health outcomes, and cost-effectiveness.Methods and findingsWe reviewed the global quantitative empirical evidence on integration published between 1 January 2010 and 10 September 2021. We included experimental and observational studies that featured both an integration intervention and a comparator in our review. Of the 7,118 unique peer-reviewed English-language studies that our search algorithm identified, 114 met all of our selection criteria for data extraction. Most of the studies (90) were conducted in sub-Saharan Africa, primarily in East Africa (55) and Southern Africa (24). The most common forms of integration were (i) HIV testing and counselling added to non-HIV services and (ii) non-HIV services added to antiretroviral therapy (ART). The most commonly integrated non-HIV services were maternal and child healthcare, tuberculosis testing and treatment, primary healthcare, family planning, and sexual and reproductive health services. Values for HIV care cascade outcomes tended to be better in integrated services: uptake of HIV testing and counselling (pooled risk ratio [RR] across 37 studies: 1.67 [95% CI 1.41–1.99], p < 0.001), ART initiation coverage (pooled RR across 19 studies: 1.42 [95% CI 1.16–1.75], p = 0.002), time until ART initiation (pooled RR across 5 studies: 0.45 [95% CI 0.20–1.00], p = 0.050), retention in HIV care (pooled RR across 19 studies: 1.68 [95% CI 1.05–2.69], p = 0.031), and viral suppression (pooled RR across 9 studies: 1.19 [95% CI 1.03–1.37], p = 0.025). Also, treatment success for non-HIV-related diseases and conditions and the uptake of non-HIV services were commonly higher in integrated services. We did not find any significant differences for the following outcomes in our meta-analyses: HIV testing yield, ART adherence, HIV-free survival among infants, and HIV and non-HIV mortality. We could not conduct meta-analyses for several outcomes (HIV infections averted, costs, and cost-effectiveness), because our systematic review did not identify sufficient poolable studies. Study limitations included possible publication bias of studies with significant or favourable findings and comparatively weak evidence from some world regions and on integration of services for key populations in the HIV response.ConclusionsIntegration of HIV services and other health services tends to improve health and health systems outcomes. Despite some scientific limitations, the global evidence shows that service integration can be a valuable strategy to boost the sustainability of the HIV response and contribute to the goal of ‘ending AIDS by 2030’, while simultaneously supporting progress towards universal health coverage.

Caroline Bulstra and co-workers assess evidence on the benefits of service integration in the HIV care cascade.  相似文献   
38.
Two syntopic morphotypes of the genus Hypostomus - H. nigromaculatus and H. cf. nigromaculatus (Atlantico Stream, Paraná State) - were compared through the allozyme electrophoresis technique. Twelve enzymatic systems (AAT, ADH, EST, GCDH, G3PDH, GPI, IDH, LDH, MDH, ME, PGM and SOD) were analyzed, attributing the score of 20 loci, with a total of 30 alleles. Six loci were diagnostic (Aat-2, Gcdh-1, Gpi-A, Idh-1, Ldh-A and Mdh-A), indicating the presence of interjacent reproductive isolation. The occurrence of few polymorphic loci acknowledge two morphotypes, with heterozygosity values He = 0.0291 for H. nigromaculatus and He = 0.0346 for H. cf. nigromaculatus. F(IS) statistics demonstrated fixation of the alleles in the two morphotypes. Genetic identity (I) and distance (D) of Nei (1978) values were I = 0.6515 and D = 0.4285. The data indicate that these two morphotypes from the Atlantico Stream belong to different species.  相似文献   
39.
The Scottish Structural Proteomics Facility was funded to develop a laboratory scale approach to high throughput structure determination. The effort was successful in that over 40 structures were determined. These structures and the methods harnessed to obtain them are reported here. This report reflects on the value of automation but also on the continued requirement for a high degree of scientific and technical expertise. The efficiency of the process poses challenges to the current paradigm of structural analysis and publication. In the 5 year period we published ten peer-reviewed papers reporting structural data arising from the pipeline. Nevertheless, the number of structures solved exceeded our ability to analyse and publish each new finding. By reporting the experimental details and depositing the structures we hope to maximize the impact of the project by allowing others to follow up the relevant biology.  相似文献   
40.
A hydrogeologic model of submarine groundwater discharge (SGD) to the near-shore environment at a site on the northeast Gulf of Mexico has been developed to provide a basis for comparison with measurements of SGD made using seepage meters, and with estimates derived from chemical tracers. The hydrogeologic model incorporates the seaward movement of fresh water and the recirculation of sea water at the fresh water–salt water interface. The hydrostratigraphy at the site includes the Surficial Aquifer, a thin confining unit known as the Intracoastal Formation, and the underlying Upper Floridan Aquifer. It is not possible to explain either the magnitude or spatial distribution of SGD recorded by the seepage meters, or the magnitude of SGD estimated using radium and radon tracers, if only steady state flow in the Surficial Aquifer is considered. Nor does it appear likely that the difference between the model-based prediction of SGD and the field-based estimates can be fully resolved by leakage across the Intracoastal Formation from a source in the Floridan Aquifer. These results suggest that processes driven by variations in fluid pressure in the marine water column, which occur on a variety of time scales, be examined to quantify their contribution to fluid circulation within and discharge from that segment of the Surficial Aquifer located beyond the low tide line.  相似文献   
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