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761.
Synthesis and activity of a series of 3-aroyl-derived analogs of novel pyrrolocarbazole 1 as poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors are disclosed.  相似文献   
762.
Mohan S  Pinto BM 《Carbohydrate research》2007,342(12-13):1551-1580
Natural products with interesting biological properties and structural diversity have often served as valuable lead drug candidates for the treatment of human diseases. Salacinol, a naturally occurring alpha-glucosidase inhibitor, was shown to be one of the active principles of the aqueous extract of a medicinal plant that has been prescribed traditionally as an Ayurvedic treatment for type II diabetes. Salacinol contains an intriguing zwitterionic sulfonium-sulfate structure that comprises a 1,4-anhydro-4-thio-D-arabinitol core and a polyhydroxylated acyclic chain. Due to the unique structural features and its potential to become a lead drug candidate in the treatment of type II diabetes, a great deal of attention has been focused on salacinol and its analogues. Since the isolation of salacinol, several papers describing various synthetic routes to salacinol and its analogues have appeared in the literature. This review is aimed at highlighting the synthetic aspects of salacinol and related compounds as well as their structure-activity relationship studies.  相似文献   
763.
Given that a large number of candidate genes coding for a tendency toward obesity have been identified and some findings have been replicated, we explored characteristics of those who would be most likely to obtain future genetic testing for this tendency. During a series of focus groups, obese respondents rated their likelihood of obtaining testing under conditions in which either genetically-targeted drug treatment would be available, a positive test would be associated with a prognosis for developing diabetes, or neither of these. Interest in testing was greater given the first two scenarios than the third. Older age and belief that genetics were an important cause of obesity were associated with greater interest. For the first two scenarios, higher educational status was associated with greater interest, while for the third, respondents who said emotional issues caused overweight and those who crash-dieted intermittently were more likely to want genetic testing. Although further research is required to validate these findings, this study is the first published report of respondents’ ratings of likelihood to obtain genetic testing for propensity to obesity, and suggests strong interest in genetic testing among some people, even in the absence of further treatment implications of the test.  相似文献   
764.
Signal integration in the galactose network of Escherichia coli   总被引:1,自引:1,他引:0  
  相似文献   
765.
Phylogenetic analyses of Erysiphe alphitoides s. lat. using sequences of the rDNA ITS region and the D1/D2 domains of the 28S rDNA revealed a complex consisting of several genetically and morphologically distinguished taxa, including the already described Erysiphe alphitoides s. str. and E. hypophylla. The ascomata (chasmothecia) of E. hypophylla are morphologically very similar to those of E. alphitoides, but the two species are easily distinguishable by their symptoms, as well as the shape and size of the conidia. The fungus on Quercus phillyraeoides, distributed in warmer regions in southern Japan, is genetically clearly separated from E. alphitoides s. str., and morphologically characterized by having chasmothecia with appendages consistently shorter than the chasmothecial diameter. This fungus, named Erysiphe quercicola in this paper, is also able to infect some other oak species, and it is genetically identical with anamorphs on some tropical trees of other host genera. Collections of E. alphitoides s. lat. on Quercus acutissima and Q. variabilis, both belonging to Quercus sect. Cerris, are genetically distinct from E. alphitoides s. str., E. hypophylla and E. quercicola. They form two genetically and morphologically differentiated groups. The hypophyllous taxon on Q. acutissima and Q. variabilis, named Erysiphe hypogena in this paper, is characterized by forming distinctive persistent hypophyllous mycelial patches, causing necrotic discolouration of the host tissue. The epiphyllous taxon on these hosts, for which the name E. epigena is proposed, differs in having epiphyllous mycelium, smaller chasmothecia with fewer appendages, and does not cause leaf discolouration.  相似文献   
766.
767.
Reproductive characteristics of tigers (Panthera tigris) are important to understand population viability. We studied the reproductive parameters of female Bengal tigers (P. t. tigris) in a dry, tropical, deciduous habitat in Ranthambhore Tiger Reserve (RTR), western India, from April 2005 to March 2010. We monitored tigers by direct observation and with cameras placed throughout their habitat. The potential breeding population included 13 adult females. The average age at first reproduction was 3.3 years; 34 cubs were born during the study period (6.2?±?0.82 per year). Sixty-six percent of the births occurred between October and December. Mean litter size was 2.26?±?0.52 (n?=?13, range?=?1–3). The sex ratio of 32 cubs was 1.29 M:1.00 F. The survival rate of cubs (<12 months) was 85 % (95 % CI?=?0.68–0.94), whereas that of juveniles (12–24 months), and subadults (24–36 months) was 79 % (95 % CI?=?0.61–0.91). All breeding females were >3 years old. Only 2 of the 13 females reproduced twice during the 5 years of the study. The birth interval was 33.4?±?3.7 months (range 24–65 months). The mean reproductive rate was 0.59?±?0.23 cubs/female/year. Our study indicates that tiger populations can grow rapidly if the habitat provides adequate protection, an adequate population of prey, and minimal to no poaching.  相似文献   
768.
Liamocins are structurally unique, heavier-than-water “oils” produced by certain strains of Aureobasidium pullulans. The aim of the current study is to identify new sources of liamocins and evaluate their potential as anticancer agents. Nine strains of A. pullulans from phylogenetic clades 8, 9, and 11 were examined for the first time for production of liamocins. Strains in these clades have only been isolated from tropical environments, and all strains tested here were from various locations in Thailand. Strains RSU 9, RSU 21, and RSU 29, all from clade 11, produced from 7.0 to 8.6 g liamocins/l from medium containing 5 % sucrose. These are the highest yields of liamocins that we have found thus far. These strains also produced from 9.4 to 17 g pullulan/l. The structural identity of liamocins was confirmed by matrix-assisted laser desorption/ionization mass spectrometry; differential spectra were obtained in which the dominant ion was either at about m/z 805.5 or m/z 949.6, consistent with the structure of liamocins. Liamocins from A. pullulans strains RSU 9 and RSU 21 inhibited two human breast cancer cell lines and a human cervical cancer cell line (IC50 values of 32.2 ± 1.4 to 63.1 ± 2.4 μg liamocins/ml) but were not toxic to a normal cell line. Liamocins weakly inhibited a strain of Enterococcus faecalis, but did not inhibit strains of Lactobacillus fermentum, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Thus, A. pullulans phylogenetic clade 11 is a promising source of liamocins, and these compounds merit further examination as potential anticancer agents.  相似文献   
769.
770.
Nesterenkonia massiliensis sp. nov., strain NP1T, is the type strain of Nesterenkonia massiliensis sp. nov., a new species within the genus Nesterenkonia. This strain, whose genome is described here, was isolated from the feces of a 32-year-old French woman suffering from AIDS and living in Marseille. Nesterenkonia massiliensis is a Gram-positive aerobic coccus. Here, we describe the features of this bacterium, together with the complete genome sequencing and annotation. The 2,726,371 bp long genome (one chromosome but no plasmid) contains 2,663 protein-coding and 51 RNA genes, including 1 rRNA operon.  相似文献   
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