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1.
We have presented a rapid and reliable method of finding lost injection valves. (A frustrating footnote, however, is that 1 week later the port had again migrated and could not be located. Since the further anticipated gain was marginal, the bladder was already nearly expanded, and the expense for repeated ultrasound was a consideration, no further attempts were made to locate this port by ultrasound for further filling).  相似文献   
2.
Actinobacillus actinomycetemcomitans leukotoxin has been implicated as a virulence factor in human infections. To initiate delineation of leukotoxin structure/function relationships, molecular cloning of the leukotoxin gene was carried out. When an A. actinomycetemcomitans genomic DNA library in lambda EMBL3 was screened using a 1.3-kilobase pair restriction fragment containing a portion of the leukotoxin gene, 13 positive recombinants were identified. One recombinant, designated lambda OP8, containing a 16-kilobase pair insert was selected for detailed study. Lysates from lambda OP8, but not control lysates, exhibited leukotoxic activity with target cell specificity identical to the native toxin. Western blots identified the recombinant-produced toxin as a 125-kDa protein doublet identical in mobility to the native toxin. Restriction enzyme and extensive DNA analyses demonstrated that the leukotoxin gene showed strong homology to two other toxins produced by Escherichia coli and Pasteurella haemolytica. As in the other two species, the A. actinomycetemcomitans toxin is contained in a cluster of four genes in which the A gene encodes the toxin and the products of the B, C, and D genes are involved in posttranslational modification of the toxin and its membrane insertion and secretion. The target cell specificity of the A. actinomycetemcomitans toxin differs from the other two toxins and is restricted to human and some non-human primate cells of the monomyelocytic lineage. The A. actinomycetemcomitans leukotoxin is not secreted but remains associated with the bacterial membrane, possibly through a hydrophobic domain at the carboxyl terminus which distinguishes it from the E. coli and P. haemolytica toxins.  相似文献   
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Reduced pulmonary function and elevated serum cholesterol levels are recognized risk factors for cardiovascular disease. Currently, there is some controversy concerning relationships between cholesterol, LDL-cholesterol, HDL-cholesterol, serum triglycerides and lung function. However, most previous studies compared patients suffering from chronic obstructive pulmonary disease (COPD) with healthy controls, and only a small number examined this relationship in population-based cohorts. Moreover, lipoprotein a [Lp(a)], another lipid parameter independently associated with cardiovascular diseases, appears not to have been addressed at all in studies of lung function at the population level. Here, we determined relationships between lung function and several lipid parameters including Lp(a) in 606 older community-dwelling participants (55.1% women, 68±4 years old) from the Berlin Aging Study II (BASE-II). We found a significantly lower forced expiration volume in 1 second (FEV1) in men with low Lp(a) concentrations (t-test). This finding was further substantiated by linear regression models adjusting for known covariates, showing that these associations are statistically significant in both men and women. According to the highest adjusted model, men and women with Lp(a) levels below the 20th percentile had 217.3ml and 124.2ml less FEV1 and 239.0ml and 135.2ml less FVC, respectively, compared to participants with higher Lp(a) levels. The adjusted models also suggest that the known strong correlation between pro-inflammatory parameters and lung function has only a marginal impact on the Lp(a)-pulmonary function association. Our results do not support the hypothesis that higher Lp(a) levels are responsible for the increased CVD risk in people with reduced lung function, at least not in the group of community-dwelling older people studied here.  相似文献   
5.

Background  

Sepsis (bloodstream infection) is the leading cause of death in non-surgical intensive care units. It is diagnosed in 750,000 US patients per annum, and has high mortality. Current understanding of sepsis is predominately observational and correlational, with only a partial and incomplete understanding of the physiological dynamics underlying the syndrome. There exists a need for dynamical models of sepsis progression, based upon basic physiologic principles, which could eventually guide hourly treatment decisions.  相似文献   
6.
Pollen flow from a 0.46 ha plot of genetically engineered (GE) Prunus domestica located in West Virginia, USA was evaluated from 2000–2010. Sentinel plum trees were planted at distances ranging from 132 to 854 m from the center of the GE orchard. Plots of mixed plum varieties and seedlings were located at 384, 484 and 998 m from the GE plot. Bee hives (Apis mellifera) were dispersed between the GE plum plot and the pollen flow monitoring sites. Pollen-mediated gene flow from out of the GE plum plot to non-GE plums under the study conditions was low, only occurring at all in 4 of 11 years and then in only 0.31% of the 12,116 seeds analyzed. When it occurred, gene flow, calculated as the number of GUS positive embryos/total embryos sampled, ranged from 0.215% at 132 m from the center of the GE plum plot (28 m from the nearest GE plum tree) to 0.033–0.017% at longer distances (384–998 m). Based on the percentage of GUS positive seeds per individual sampled tree the range was 0.4% to 12%. Within the GE field plot, gene flow ranged from 4.9 to 39%. Gene flow was related to distance and environmental conditions. A single year sample from a sentinel plot 132 m from the center of the GE plot accounted for 65% of the total 11-year gene flow. Spatial modeling indicated that gene flow dramatically decreased at distances over 400 m from the GE plot. Air temperature and rainfall were, respectively, positively and negatively correlated with gene flow, reflecting the effects of weather conditions on insect pollinator activity. Seed-mediated gene flow was not detected. These results support the feasibility of coexistence of GE and non-GE plum orchards.  相似文献   
7.
The objective of the study was to compare the level of dissatisfaction with body image of men and women of the social elite in the Wielkopolska region, Poland, in the light of anthropometric indicators.  相似文献   
8.

Background  

The timing of the origin of introns is of crucial importance for an understanding of early genome architecture. The Exon theory of genes proposed a role for introns in the formation of multi-exon proteins by exon shuffling and predicts the presence of conserved splice sites in ancient genes. In this study, large-scale analysis of potential conserved splice sites was performed using an intron-exon database (ExInt) derived from GenBank.  相似文献   
9.
One of the unique insights provided by the growing number of fully sequenced genomes is the pervasiveness of gene duplication and gene loss. Indeed, several metrics now suggest that rates of gene birth and death per gene are only 10–40% lower than nucleotide substitutions per site, and that per nucleotide, the consequent lineage‐specific expansion and contraction of gene families may play at least as large a role in adaptation as changes in orthologous sequences. While gene family evolution is pervasive, it may be especially important in our own evolution since it appears that the “revolving door” of gene duplication and loss has undergone multiple accelerations in the lineage leading to humans. In this paper, we review current understanding of gene family evolution including: methods for inferring copy number change, evidence for adaptive expansion and adaptive contraction of gene families, the origins of new families and deaths of previously established ones, and finally we conclude with a perspective on challenges and promising directions for future research.  相似文献   
10.
In this study, we report on the isolation of a PDZ domain protein, here designated as IIP-1, insulin-like growth factor-1 (IGF-1) receptor-interacting protein-1, which binds to the IGF-1 receptor, but not to the related insulin receptor, and which is involved in the regulation of cell motility. The interaction between the IGF-1 receptor and IIP-1 as well as a splice variant IIP-1/p26 was demonstrated in the yeast two-hybrid system. Using co-precipitation experiments, we confirmed the interaction in transfected cells as well as in vitro. Analysis of deletion mutants indicates that the PDZ domain of IIP-1 mediates interaction with the C-terminal tail of the IGF-1 receptor (serine-threonine-cysteine). This finding demonstrates that the C terminus of the IGF-1 receptor acts as novel PDZ domain binding site. Immunofluorescence analysis revealed an overlapping localization of IIP-1 and the IGF-1 receptor in the breast cancer cell line MCF-7. A functional connection between IIP-1 and the IGF-1 receptor is further supported by the finding that the level of expression of IIP-1 and the IGF-1 receptor strongly correlates in different normal and cancer cells. Furthermore, overexpression of IIP-1 resulted in an attenuation of migration of MCF-7 cells, which is one of the biological activities mediated by the IGF-1 signaling system.  相似文献   
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