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Hsieh CL Oakley-Girvan I Balise RR Halpern J Gallagher RP Wu AH Kolonel LN O'Brien LE Lin IG Van Den Berg DJ Teh CZ West DW Whittemore AS 《American journal of human genetics》2001,69(1):148-158
We conducted a genomewide screen for prostate cancer-susceptibility genes on the basis of data from 98 families from the United States and Canada that had three or more verified diagnoses of prostate cancer among first- and second-degree relatives. We found a statistically significant excess of markers for which affected relatives exhibited modest amounts of excess allele-sharing; however, no single chromosomal region contained markers with excess allele-sharing of sufficient magnitude to indicate unequivocal evidence of linkage. Positive linkage signals of nominal statistical significance were found in two regions (5p-q and 12p) that have been identified as weakly positive in other data sets and in region 19p, which has not been identified previously. All these signals were considerably stronger for analyses restricted to families with mean age at onset below the median than for analyses of families with mean age at onset above the median. The data provided little support for any of the putative prostate cancer-susceptibility genes identified in other linkage studies. 相似文献
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Jacques M Mathieu John Schloendorn Bruce E Rittmann Pedro JJ Alvarez 《Microbial cell factories》2009,8(1):21-18
Catabolic insufficiency in humans leads to the gradual accumulation of a number of pathogenic compounds associated with age-related
diseases, including atherosclerosis, Alzheimer's disease, and macular degeneration. Removal of these compounds is a widely
researched therapeutic option, but the use of antibodies and endogenous human enzymes has failed to produce effective treatments,
and may pose risks to cellular homeostasis. Another alternative is "medical bioremediation," the use of microbial enzymes
to augment missing catabolic functions. The microbial genetic diversity in most natural environments provides a resource that
can be mined for enzymes capable of degrading just about any energy-rich organic compound. This review discusses targets for
biodegradation, the identification of candidate microbial enzymes, and enzyme-delivery methods. 相似文献
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Sperm-induced calcium (Ca2+) changes were examined in zona pellucida-intact, mature bovine eggs injected with the fluorescent Ca2+ indicator fura-2 dextran (fura-2 D). Fifty four percent (37/68) of the dye-injected, inseminated bovine eggs were fertilized and 43% (16/37) of the fertilized eggs exhibited Ca2+ elevations during the time of measurement. All (16/16) of the eggs with Ca2+ elevations were fertilized but none of the unfertilized eggs (0/31) showed intracellular Ca2+ elevations. Six of 13 eggs that were later examined and found to be fertilized at the time of the Ca2+ recordings did not show sperm-induced Ca2+ elevations. Fifty percent (8/16) of the eggs with Ca2+ elevations exhibited a single Ca2+ rise as a response to sperm penetration during the 60-min period in which these eggs were monitored. Twelve percent (2/16) of the eggs responded with two Ca2+ elevations spaced by 50- and 51-min intervals and 38% (6/16) of the eggs exhibited multiple elevations with intervals of 15-29 min. In the latter group, one egg was polyspermic. The mean amplitude of the sperm-induced Ca2+ elevations was 564 +/- 58 nM. Eggs with single elevations reached higher peak concentrations than eggs with multiple elevations (p < 0.05). The mean duration of the Ca2+ elevations was 166 +/- 13 sec and was similar among eggs with different Ca2+ patterns. The first elevations detected occurred at a mean of 6.6 +/- 0.5 h after insemination. Fertilization in this study was confirmed by looking at pronuclear formation 16 h post-insemination or by DNA staining immediately after the fluorescence readings. Eggs exhibiting Ca2+ elevations ranged in stage of fertilization from just penetrated to pronuclear. Injection of inositol 1,4,5 trisphosphate (5 microM in the injection pipette) into 6 bovine eggs induced an immediate Ca2+ elevation with a mean peak Ca2+ value of 700 +/- 60 nM and a mean duration of 103 +/- 21 sec. Incubation of bovine eggs with 200 microM thimerosal induced periodic Ca2+ rises. The mean number of Ca2+ elevations observed in 35 min of recordings was 3.0 +/- 0.5 (n = 9, range 1-5). The mean peak Ca2+ value of the first thimerosal-induced Ca2+ elevation was 990 +/- 210 nM. The results of this study indicate that fertilization can evoke intracellular Ca2+ elevations in bovine eggs and that the periodicity of these Ca2+ elevations is different among eggs. Furthermore, both inositol 1,4,5-trisphosphate and thimerosal were able to induce intracellular Ca2+ release in bovine eggs. 相似文献
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Karl Rumbold Hugo JJ van Buijsen Karin M Overkamp Johan W van Groenestijn Peter J Punt J van der Mari?t Werf 《Microbial cell factories》2009,8(1):64