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Shittu ST 《Nigerian journal of physiological sciences》2011,26(2):219-233
Zingiber officinale (ginger) has been shown to be a rich source of antioxidants. Previous studies have shown that cryptorchidism causes oxidative stress. However, the possible effect of ginger in ameliorating cryptorchidism-induced oxidative stress in rat has not been investigated. The present study therefore looked into the effect of ethanol extract of ginger (EEG) on the oxidative stress in experimentally induced cryptorchidism in the rat. Twenty four (24) male Sprague-Dawley rats, weighing 170g-210g were divided into three (3) groups (A-C), of eight (8) rats each. Group A was sham-operated and treated with vehicle, Groups B and C were rendered cryptorchid treated with vehicle and EEG respectively. Cryptorchid rats had significantly lower testicular weight, sperm count, sperm motility, lower percentage sperms with normal morphology, superoxide dismutase (SOD),.. 相似文献
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VINCENT GRANDPERRET VALÉRIE NICOLAS‐FRANCÈS DAVID WENDEHENNE STÉPHANE BOURQUE 《Plant, cell & environment》2014,37(6):1259-1269
Since the beginning of the 21st century, numerous studies have concluded that the plant cell nucleus is one of the cellular compartments that define the specificity of the cellular response to an external stimulus or to a specific developmental stage. To that purpose, the nucleus contains all the enzymatic machinery required to carry out a wide variety of nuclear protein post‐translational modifications (PTMs), which play an important role in signal transduction pathways leading to the modulation of specific sets of genes. PTMs include protein (de)acetylation which is controlled by the antagonistic activities of histone acetyltransferases (HATs) and histone deacetylases (HDACs). Regarding protein deacetylation, plants are of particular interest: in addition to the RPD3‐HDA1 and Sir2 HDAC families that they share with other eukaryotic organisms, plants have developed a specific family called type‐II HDACs (HD2s). Interestingly, these HD2s are well conserved in plants and control fundamental biological processes such as seed germination, flowering or the response to pathogens. The aim of this review was to summarize current knowledge regarding this fascinating, but still poorly understood nuclear protein family. 相似文献
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JUAN C. ENGEL JAMES A. DVORAK ELSA L. SEGURA MARK ST. J. CRANE 《The Journal of eukaryotic microbiology》1982,29(4):555-560
Nineteen clones of Trypanosoma cruzi were obtained as single-cell isolates from Triatoma infestans. Ten of the clones were isolates from a patient with chronic Chagas' disease; nine clones were isolates from a dog infected with T. cruzi strain CA-I isolated originally from a chronic chagasic patient. The growth kinetics and peak modal Coulter volume of these clones were characterized. Significant inter- and intra-group differences between growth rates and peak modal volumes were found. These data indicate that subpopulations and, consequently, genetic heterogeneity of T. cruzi exist in chronic chagasic patients. All of the clones infected vertebrate cells in vitro. 相似文献
107.
Endophytes, bacterial, fungal or viral, colonize plants often without causing visible symptoms. More important, they may benefit
host plants in many ways, most notably by preventing diseases caused by normally virulent pathogens. Craigella tomatoes (Lycopersicon esculentum Mill.) can be infected with Verticillium dahliae Kleb., either race 1 (Vd1) or a non-host isolate Dvd-E6 resulting in susceptibility or tolerance, respectively. The present
study sought to determine whether Dvd-E6 is endophytic and can protect tomato against Vd1. The total amount of Verticillium in stems and roots was determined by quantitative PCR; the relative amounts of Vd1 and Dvd-E6 were assessed by restriction
fragment polymorphism. When Dvd-E6 infects before or together with Vd1, Vd1 is excluded almost completely from the root but,
when Vd1 infects first, Dvd-E6 can compete on an equal basis. Previous studies suggested that Dvd-E6 suppresses symptom-related
genes, raising the possibility that Dvd-E6 simultaneously induces tolerance to Vd1. This does not seem to be entirely the
case since the minimal symptoms following Vd1 infection of Dvd-E6 tolerant Craigella result, at least in part, from restricted
Vd1 colonization. Furthermore, when Vd1 and Dvd-E6 are cultured on PDA plates alone or together, the growth rates are similar
and neither is inhibitory to the other. Dvd-E6 does not outgrow or inhibit Vd1, in vitro. The protective effect apparently
requires interplay between Dvd-E6 and the plant. Expression analyses of tomato genes involved in resistance and defence support
this interpretation. 相似文献
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SUSAN A. NADIN‐DAVIS YUQIN FENG DELPHINE MOUSSE ALEXANDER I. WANDELER STÉPHANE ARIS‐BROSOU 《Molecular ecology》2010,19(10):2120-2136
Phylogenetic analysis of a collection of rabies viruses that currently circulate in Canadian big brown bats (Eptesicus fuscus) identified five distinct lineages which have emerged from a common ancestor that existed over 400 years ago. Four of these lineages are regionally restricted in their range while the fifth lineage, comprising two‐thirds of all specimens, has emerged in recent times and exhibits a recent demographic expansion with rapid spread across the Canadian range of its host. Four of these viral lineages are shown to circulate in the US. To explore the role of the big brown bat host in dissemination of these viral variants, the population structure of this species was explored using both mitochondrial DNA and nuclear microsatellite markers. These data suggest the existence of three subpopulations distributed in British Columbia, mid‐western Canada (Alberta and Saskatchewan) and eastern Canada (Quebec and Ontario), respectively. We suggest that these three bat subpopulations may differ by their level of female phylopatry, which in turn affects the spread of rabies viruses. We discuss how this bat population structure has affected the historical spread of rabies virus variants across the country and the potential impact of these events on public health concerns regarding rabies. 相似文献
110.
ST Kew 《BMC research notes》2010,3(1):342