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The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase.  相似文献   
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Saturated and trans-unsaturated fatty acids, such as laurate and elaidate, elicited O2- generation in intact porcine and human neutrophils and also in a cell-free preparation of porcine neutrophils. The activities thus induced were comparable to those induced by cis-unsaturated fatty acids. However, the activation by saturated or trans-unsaturated fatty acids was depressed almost completely in the presence of Ca2+ at around 1 mM, which is usually contained in the media for phagocytes. In contrast, the activation by cis-unsaturated fatty acids such as arachidonate was scarcely affected by Ca2+. These findings appear to demand reevaluation of the effects of long chain fatty acids on the respiratory burst system in phagocytes.  相似文献   
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To investigate how various concentrations of serum prolactin (PRL) influence the priming effect of luteinizing hormone releasing hormone (LH-RH) on the pituitary gland, 24 women with various blood PRL concentrations received intravenous injections of 100 micrograms of synthetic LH-RH twice at an interval of 60 minutes and their serum LH and follicle-stimulating hormone (FSH) were measured and analysed. In the follicular phase with a normal PRL concentration (PRL less than 20 ng/ml, n = 6), marked first peaks of the two hormones following the first LH-RH stimulation and enhanced second peaks after the second LH-RH administration were observed, indicating a typical priming effect of LH-RH on gonadotropins, though the second response of FSH was more moderate than that of LH. In hyperprolactinemia, in which the serum PRL concentration was higher than 70 ng/ml (n = 13), the basal concentration of gonadotropins was not significantly changed but the priming effect of LH-RH on LH and FSH was significantly decreased (p less than 0.01). No marked second peaks of LH and FSH were observed, suggesting an inhibitory effect of hyperprolactinemia on the second release of LH and FSH. In contrast, this effect was restored in a group of women whose serum PRL concentration was between 30 and 50 ng/ml (n = 5). Furthermore, enhanced second peaks of both LH and FSH were noted after successful bromocriptine therapy reduced hyperprolactinemia (PRL greater than 70 ng/ml) to less than 25 ng/ml (n = 5).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Lectin binding patterns in normal human endometrium were examined by light and electron microscopy using seven different lectins (ConA, WGA, RCA, PNA, UEA-1, DBA, and SBA). For light microscopic observations, criteria based on the incidence and intensity of cells positive for the lectin staining were adopted to evaluate the different staining patterns of the proliferative and secretory endometria obtained by the avidin-biotin-peroxidase complex (ABC) technique. At the light microscopic level, ConA, WGA, and RCA stained endometrial glandular cells in both phases. The number of PNA-positive cells with the binding sites entirely limited to the apical surface tended to be reduced slightly in the secretory phase. UEA-1 weakly stained the apical surface of glandular cells in the proliferative phase but not in the secretory phase. Among the lectins used in this study, DBA and SBA displayed remarkable changes between the phases. That is, in the proliferative phase they produced only a faint or slight positive stain at the apical surface, but the incidence and intensity of DBA- and the SBA-positive glandular cells increased in the secretory phase. By electron microscopy, the reaction product of ConA was observed in the plasma membrane, endoplasmic reticulum, nuclear envelope, and the Golgi apparatus, and the binding sites of RCA and DBA were observed in the plasma and Golgi membranes. Between both phases, the reactivity of ConA and RCA showed almost no change. However, the secretory endometrial cells containing the DBA-positive Golgi apparatus were markedly increased in number compared with the proliferative ones bearing the lectin-positive organelles.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The purpose of this study was to examine the possibility of separation and quantification of serum alkaline phosphatase (ALP) isozymes in rats by wheatgerm lectin affinity electrophoresis. Cellulose acetate electrophoresis of the liver and bone ALPs without lectin results in overlapping bands, but in the presence of lectin, the mobility of the band of bone enzyme was retarded and well separated from the liver enzyme band. With this affinity electrophoretic method, we determined the serum ALP isozymes in fed and fasting rats grouped by age. As a result, the absolute activity of bone isozyme showed a downward trend with age in the fed and fasting rats. The serum ALP activity was steadily higher in fed rats than in fasting rats, and the increase was due to intestinal ALP isozyme. There was low activity bordering complete absence in liver isozyme under both nutritional conditions. The affinity electrophoretic method provided a rapid, reproducible, and relatively simple technique for further clinical characterization of ALP isozyme in the rat serum.  相似文献   
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Sea urchin embryos were vegetalized by a pulse treatment with 60 mM Li+ between 2.5 hr and 6 hr after fertilization at 20°C. Normal and Li+ -treated embryos were exposed to [35S]-methionine for 2 hr at various stages and [35S]-labeled proteins were analyzed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). On fluorograph of 2D-PAGE at the pre-hatching blastula stage, significant difference of labeled proteins between normal and vegetalized embryos was not observed in the range from neutral to acidic pH, but pls of several proteins were found to be shifted toward alkaline pH. At the mesechyme blastula stage, five major proteins [M.W. 36 K, 43 K (two species), 71 K and 150 K] were enriched in Li+-treated embryos among a few hundreds of synthesized proteins. At the late gastrula stage, the labeling intensities of these proteins except for one of 43 K proteins increased remarkably in Li+-treated embryos. Furthermore, two proteins (M.W. 105 K and 135 K) were also enriched in Li+-treated embryos at this stage. At the prism stage, these proteins enriched in Li+-treated embryos became hardly detectable, and the synthesis of at least four proteins (M.W. about 20 K, 41 K, 43 K and 200 K<) appeared to increase in normal embryos, but not in Li+-treated embryos. Synthesis of proteins eniched in Li+-treated embryos probably support endodermal cell differentiation.  相似文献   
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Summary Enzymatic DNA amplification and direct DNA sequencing were used to detect a mutation in the tyrosinase gene of an albino patient. Single-base change could be detected by direct sequencing. This base change (G to A) is thought to result in an amino acid change (Arg to Gln) in tyrosinase of the patient.  相似文献   
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Investigations were made of the growth ofNelumbo nucifera, an aquatic higher plant, in a natural stand in Lake Kasumigaura. A rise of 1.0 m in the water level after a typhoon in August 1986 caused a subsequent decrease in biomass ofN. nucifera from the maximum of 291 g d.w. m−2 in July to a minimum of 75 g d.w. m−2. The biomass recovered thereafter in shallower regions. The underground biomass in October tended to increase toward the shore. The total leaf area index (LAI) is the sum of LAI of floating leaves and emergent leaves. The maximum total LAI was 1.3 and 2.8 m2 m−2 in 1986 and 1987, respectively. LAI of floating leaves did not exceed 1 m2 m−2. The elongation rates of the petiole of floating and emergent leaves just after unrolling were 2.6 and 3.4 cm day−1, respectively. The sudden rise in water level (25 cm day−1) after the typhoon in August 1986 caused drowning and subsequent decomposition of the mature leaves. Only the young leaves were able to elongate, allowing their laminae to reach the water surface. The fluctuation in water level, characterized by the amplitude and duration of flooding and the time of flooding in the life cycle, is an important factor determining the growth and survival ofN. nucifera in Lake Kasumigaura.  相似文献   
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