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Determination of Rubella Hemagglutination-Inhibiting Antibody in Whole Blood 总被引:1,自引:0,他引:1 下载免费PDF全文
A technique is described for determination of rubella hemagglutination-inhibiting antibody in only 50 to 100 muliters of whole blood. 相似文献
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Transcriptional profiling of Caulobacter crescentus during growth on complex and minimal media 总被引:2,自引:0,他引:2 下载免费PDF全文
Hottes AK Meewan M Yang D Arana N Romero P McAdams HH Stephens C 《Journal of bacteriology》2004,186(5):1448-1461
Microarray analysis was used to examine gene expression in the freshwater oligotrophic bacterium Caulobacter crescentus during growth on three standard laboratory media, including peptone-yeast extract medium (PYE) and minimal salts medium with glucose or xylose as the carbon source. Nearly 400 genes (approximately 10% of the genome) varied significantly in expression between at least two of these media. The differentially expressed genes included many encoding transport systems, most notably diverse TonB-dependent outer membrane channels of unknown substrate specificity. Amino acid degradation pathways constituted the largest class of genes induced in PYE. In contrast, many of the genes upregulated in minimal media encoded enzymes for synthesis of amino acids, including incorporation of ammonia and sulfate into glutamate and cysteine. Glucose availability induced expression of genes encoding enzymes of the Entner-Doudoroff pathway, which was demonstrated here through mutational analysis to be essential in C. crescentus for growth on glucose. Xylose induced expression of genes encoding several hydrolytic exoenzymes as well as an operon that may encode a novel pathway for xylose catabolism. A conserved DNA motif upstream of many xylose-induced genes was identified and shown to confer xylose-specific expression. Xylose is an abundant component of xylan in plant cell walls, and the microarray data suggest that in addition to serving as a carbon source for growth of C. crescentus, this pentose may be interpreted as a signal to produce enzymes associated with plant polymer degradation. 相似文献
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A number of studies have tested the association of the complement receptor 1 (CR1) and Interleukin-10 (IL10) polymorphisms with systemic lupus erythematosus (SLE), but reported conflicting results. The aim of the study is to explore whether the CR1 and IL10 genes are associated with SLE susceptibility. We surveyed studies on the CR1 and IL10 polymorphisms and SLE using comprehensive Medline search and review of the references. A meta-analysis was conducted in a fixed effects model or random effects model based on between-study heterogeneity. Eighteen comparisons from 13 studies were included in the CR1 meta-analysis and a total of 16 separate comparisons were used for the IL10 meta-analysis. The CR1 meta-analysis showed no significant association of the CR1 functional polymorphisms with SLE. In contrast, the S structural variant of the CR1 showed a significant association (OR=1.544, 95% CI, 1.217–1.959, P<0.001). Stratification by ethnicity indicated that the CR1 S variant was associated with SLE in Caucasians (OR=1.667, 95% CI, 1.193–2.357, P=0.003). The IL10 meta-analysis showed a significant association between SLE and the G11 allele of IL10.G (OR=1.279, 95% CI; 1.027–1.593, P=0.028) in whole populations, and IL10 promoter −1082G allele was associated with SLE in Asians (OR=1.358, 95% CI; 1.015–1.816, P=0.039). In conclusion, the CR1 meta-analysis revealed the association of the S structural variant of the CR1 with SLE and the IL10 meta-analysis showed the association of IL10.G11 allele and SLE in whole populations and the association between promoter -A1082G polymorphism and SLE in Asians. 相似文献
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The endangered mountain zebra (Equus zebra) is endemic to the semi-arid inhospitable mountainous escarpments of southern Africa. The species is divided taxonomically
into two geographically separated subspecies, each with differing recent population histories. In Namibia, Hartmann’s mountain
zebra (E. z. hartmannae) is common and occurs in large free-ranging populations, whereas in South Africa, prolonged hunting and habitat destruction
over the last 300 years has decimated populations of the Cape mountain zebra (E. z. zebra). In this study, we investigate the consequences of these divergent demographic histories for population genetic diversity
and structure. We also examine the phylogeographic relationship between the two taxonomic groups. Genetic information was
obtained at 15 microsatellite loci for 291 individuals from a total of 10 populations as well as 445 bp of the mitochondrial
control region sequence data from 77 individuals. Both model-based and standard analytical approaches were used to examine
the data. Both types of marker returned levels of diversity and structure that were consistent with population history. Low
genetic variation within individual Cape mountain zebra populations, the characteristic indicator of population fragmentation
and drift, was offset by moderate variation in the entire E. z. zebra sample. This implies that higher levels of diversity still exist within the Cape mountain zebra gene pool. A management strategy
that entailed the mixing of aboriginal populations is therefore advocated in order to halt the further loss of Cape mountain
zebra genetic diversity. Allele frequencies in Hartmann’s mountain zebra were relatively resilient to demographic fluctuations.
Due to the high incidence of mitochondrial haplotype sharing between populations, the hypothesis that Cape and Hartmann’s
mountain zebra mitochondrial lineages were reciprocally monophyletic was not supported. However, the presence of private alleles
at nuclear loci rendered the two subspecies genetically distinct evolutionary significant units. 相似文献
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Maternal embryonic leucine zipper kinase (MELK) regulates multipotent neural progenitor proliferation 下载免费PDF全文
Nakano I Paucar AA Bajpai R Dougherty JD Zewail A Kelly TK Kim KJ Ou J Groszer M Imura T Freije WA Nelson SF Sofroniew MV Wu H Liu X Terskikh AV Geschwind DH Kornblum HI 《The Journal of cell biology》2005,170(3):413-427
Maternal embryonic leucine zipper kinase (MELK) was previously identified in a screen for genes enriched in neural progenitors. Here, we demonstrate expression of MELK by progenitors in developing and adult brain and that MELK serves as a marker for self-renewing multipotent neural progenitors (MNPs) in cultures derived from the developing forebrain and in transgenic mice. Overexpression of MELK enhances (whereas knockdown diminishes) the ability to generate neurospheres from MNPs, indicating a function in self-renewal. MELK down-regulation disrupts the production of neurogenic MNP from glial fibrillary acidic protein (GFAP)-positive progenitors in vitro. MELK expression in MNP is cell cycle regulated and inhibition of MELK expression down-regulates the expression of B-myb, which is shown to also mediate MNP proliferation. These findings indicate that MELK is necessary for proliferation of embryonic and postnatal MNP and suggest that it regulates the transition from GFAP-expressing progenitors to rapid amplifying progenitors in the postnatal brain. 相似文献
90.
Vance BA Harley PH Backlund PS Ward Y Phelps TL Gress RE 《Archives of biochemistry and biophysics》2005,438(1):11-20
CD69 is thought to be a pluripotent signaling molecule expressed on the surface of a number of activated leukocytes including B, T, and NK cells, monocytes, neutrophils, and platelets. While some advances have been made regarding the mechanisms by which CD69 may participate in such diverse functions as cell aggregation, cellular cytotoxicity, and release of cytokines and inflammatory mediators, the most proximal links of signal initiation have not been identified. Our study has identified, by immunoprecipitation and direct protein sequencing (LC/MS/MS), binding of CD69 to an N-terminal protein fragment of calreticulin expressed on the cell surface of human PBMCs. Given the recently identified roles calreticulin plays in cell adhesion and angiogensis, the identification of CD69 binding directly to calreticulin may provide insights into mechanism(s) by which CD69 or other CD69 family members, i.e., LLT1 and AICL participates in such diverse functions. 相似文献