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241.
Scott M. Emrich Ryan E. Yoast Ping Xin Vikas Arige Larry E. Wagner Nadine Hempel Donald L. Gill James Sneyd David I. Yule Mohamed Trebak 《Cell reports》2021,34(9):108760
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242.
Lu Tian Hua Jin Hajime Uno Ying Lu Bo Huang Keaven M. Anderson LJ Wei 《Biometrics》2020,76(4):1157-1166
The t-year mean survival or restricted mean survival time (RMST) has been used as an appealing summary of the survival distribution within a time window [0, t]. RMST is the patient's life expectancy until time t and can be estimated nonparametrically by the area under the Kaplan-Meier curve up to t. In a comparative study, the difference or ratio of two RMSTs has been utilized to quantify the between-group-difference as a clinically interpretable alternative summary to the hazard ratio. The choice of the time window [0, t] may be prespecified at the design stage of the study based on clinical considerations. On the other hand, after the survival data have been collected, the choice of time point t could be data-dependent. The standard inferential procedures for the corresponding RMST, which is also data-dependent, ignore this subtle yet important issue. In this paper, we clarify how to make inference about a random “parameter.” Moreover, we demonstrate that under a rather mild condition on the censoring distribution, one can make inference about the RMST up to t, where t is less than or even equal to the largest follow-up time (either observed or censored) in the study. This finding reduces the subjectivity of the choice of t empirically. The proposal is illustrated with the survival data from a primary biliary cirrhosis study, and its finite sample properties are investigated via an extensive simulation study. 相似文献
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Renata Santana Silva Leonardo Monteiro Ribeiro Maria Olívia Mercadante-Simões Yule Roberta Ferreira Nunes Paulo Sérgio Nascimento Lopes 《Flora》2014
Associations of recalcitrance and dormancy are rare, and little information is available concerning the structure of seeds demonstrating this type of behavior or their ecological implications. Mauritia flexuosa is a palm tree associated with swampy environments in the Amazon rainforest and areas of Cerrado (neotropical savanna), the latter biome having marked climatic seasonality. We describe the structures and physiological aspects of the seeds and seedlings of this species to examine its adaptations to swampy environments and its germination control mechanisms, as well as the relationship between recalcitrance and dormancy in terms of reproductive success. Morphoanatomy and histochemistry of the seeds and seedlings were evaluated using standard methodologies, and the effects of temperature and operculum removal on germination were investigated. Differentiated tracheal elements in the embryo are associated with recalcitrance, and presence of numerous stomata on the embryo and the abundance of secondary metabolite compounds in the seedling indicate their adaptations to swampy environments. The inability of the embryo to overcome the resistance of the adjacent tissues determines dormancy of the physiological type, thus the removal of the operculum is an efficient method for promoting propagation. Cellular elongation in the cotyledon promotes seedling protrusion. Mobilization of endosperm reserves is achieved by symplastic flux and is associated with overcoming of dormancy by weakening the tissues adjacent to the embryo. The association between recalcitrance, which favors adaptation to swampy environments, and dormancy, which favors dispersal, is crucial for the reproductive success of this species and its broad geographical distribution. 相似文献
246.
Shiwei Bai Jie Liu Cheng Chang Ling Zhang Takaki Maekawa Qiuyun Wang Wenkai Xiao Yule Liu Jijie Chai Frank L. W. Takken Paul Schulze-Lefert Qian-Hua Shen 《PLoS pathogens》2012,8(6)
Plant intracellular immune receptors comprise a large number of multi-domain proteins resembling animal NOD-like receptors (NLRs). Plant NLRs typically recognize isolate-specific pathogen-derived effectors, encoded by avirulence (AVR) genes, and trigger defense responses often associated with localized host cell death. The barley MLA gene is polymorphic in nature and encodes NLRs of the coiled-coil (CC)-NB-LRR type that each detects a cognate isolate-specific effector of the barley powdery mildew fungus. We report the systematic analyses of MLA10 activity in disease resistance and cell death signaling in barley and Nicotiana benthamiana. MLA10 CC domain-triggered cell death is regulated by highly conserved motifs in the CC and the NB-ARC domains and by the C-terminal LRR of the receptor. Enforced MLA10 subcellular localization, by tagging with a nuclear localization sequence (NLS) or a nuclear export sequence (NES), shows that MLA10 activity in cell death signaling is suppressed in the nucleus but enhanced in the cytoplasm. By contrast, nuclear localized MLA10 is sufficient to mediate disease resistance against powdery mildew fungus. MLA10 retention in the cytoplasm was achieved through attachment of a glucocorticoid receptor hormone-binding domain (GR), by which we reinforced the role of cytoplasmic MLA10 in cell death signaling. Together with our data showing an essential and sufficient nuclear MLA10 activity in disease resistance, this suggests a bifurcation of MLA10-triggered cell death and disease resistance signaling in a compartment-dependent manner. 相似文献
247.
The objective of this work was to evaluate the production of bioethanol from a new Korean variety of corn (Gangdaok) and to
assess low temperature pre-treatment of corn mashes before simultaneous saccharification and fermentation. Corn mashes containing
178 g/L of total sugar were fermented with Saccharomyces cerevisiae CHY 1011(KCTC 11250BP) at 35°C. Fermentation of mash supplemented with solid glucoamylase was completed within 48 h, and
the ethanol produced was 474.0 and 473.1 L/ton as dry base with low temperature pre-treatment and pressure pretreatment, respectively.
Furthermore, the DDGS of Gangdaok cultivar contained more essential amino acids (21.1 mg/g) than did Ambrosia cultivar (USA
corn), which is a widely used feedstock. In addition, there were no significant differences in ethanol yield or amino acid
concentration in DDGS between low temperature pre-treatment and pressure pretreatment. The results show that Gangdaok holds
potential economic advantages if applied to the bioethanol and feed industries. 相似文献
248.
G. Udny Yule 《Journal of genetics》1923,13(3):255-331
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