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排序方式: 共有271条查询结果,搜索用时 15 毫秒
121.
Pseudotulostoma volvata (O. K. Mill. and T. W. Henkel) is a morphologically unusual member of the otherwise hypogeous Elaphomycetaceae due to its epigeous habit and exposed gleba borne on an elevated stalk at maturity. Field observations in Guyana indicated that P. volvata was restricted to rain forests dominated by ectomycorrhizal (EM) Dicymbe corymbosa (Caesalpiniaceae), suggesting an EM nutritional mode for the fungus. In this paper, we confirm the EM status of P. volvata with a combination of morphological, molecular, and mycosociological data. The EM status for P. volvata corroborates its placement in the ectotrophic Elaphomycetaceae. 相似文献
122.
The alternative splicing of tau exon 10 and its regulatory proteins CLK2 and TRA2-BETA1 changes in sporadic Alzheimer's disease 总被引:1,自引:0,他引:1
123.
? Premise of the study: Sequestrate basidiomycete fungi (e.g. "gasteromycetes") have foregone ballistospory and evolved alternative, often elaborate mechanisms of basidiospore dispersal with highly altered basidioma morphology. Sequestrate fungi have independently evolved in numerous Agaricomycete lineages, confounding taxonomic arrangements of these fungi for decades. Understanding the multiple origins and taxonomic affinities of sequestrate fungi provides insight into the evolutionary forces that can drastically alter basidioma morphology. In the neotropical rainforests of the Guiana Shield, we encountered a remarkable sequestrate fungus fruiting directly on decaying hardwood roots. The fungus' singular combination of traits include a wood-decaying habit; black, verrucose peridium; reduced stipe; and gelatinized basidiospore mass. ? Methods: Guyanagaster necrorhiza gen. et sp. nov. is described. Macro- and micromorphological characters were assessed and compared to most similar taxa. To determine the phylogenetic affinities of the fungus, DNA sequence data were obtained for the 18S, ITS, and 28S rDNA, RBP2, and EF1α regions and subjected to single- and multi-gene analyses. DNA sequences from fungal vegetative organs growing on decaying woody roots confirmed the wood-inhabiting lifestyle of Guyanagaster. ? Key results: Guyanagaster is morphologically unique among sequestrate fungi worldwide. Phylogenetic evidence places Guyanagaster in close relation to the wood-decaying mushroom genus Armillaria in the Physalacriaceae (Agaricales, Agaricomycetes, Basidiomycota). ? Conclusions: Guyanagaster represents an independently evolved sequestrate form within the Physalacriaceae. Although molecular data confirm that Guyanagaster is closely related to Armillaria, the unusual features of this fungus suggest a case of radically divergent morphological evolution. 相似文献
124.
New reactor concepts as multi-parallel screening systems or disposable bioreactor systems for decentralized and reproducible
production increase the need for new and easy applicable sensor technologies to access data for process control. These sophisticated
reactor systems require sensors to work with the lowest sampling volumes or, even better, to measure directly in situ, but
in situ sensors are directly incorporated into a reactor or fermenter within the sterility barrier and have therefore to stand
the sterilization procedures. Consequently, these in situ sensor technologies should enable the measurement of multi-analytes
simultaneously online and in real-time at a low price for the robust sensing element. Current research therefore focuses on
the implementation of noninvasive spectroscopic and optical technologies, and tries to employ them through fiber optics attached
to disposable sensing connectors. Spectroscopic methods reach from ultraviolet to infrared and further comprising fluorescence
and Raman spectroscopy. Also, optic techniques like microscopy are adapted for the direct use in bioreactor systems (Ulber
et al. in Anal Bioanal Chem 376:342–348, 2003) as well as various electrochemical methods (Joo and Brown in Chem Rev 108:638–651, 2008). This review shows the variety of modern in situ sensing principles in bioprocess monitoring with emphasis on spectroscopic
and optical techniques and the progress in the adaption to latest reactor concepts. 相似文献
125.
Reproductive success is a critical fitness attribute that is directly influenced by resource availability. Here, we investigate the effects of diet‐based resource availability on three interrelated aspects of reproductive success: a change in mating system based on mate availability, consequent inbreeding depression, and the deterioration of reproductive efficiency with age (senescence). We employed a factorial experimental design using 22 full‐sib families of the hermaphroditic freshwater snail Physa acuta to explore these interactions. Individual snails were reared in one of two mate‐availability treatments (isolated [selfing] or occasionally paired [outcrossing]) and one of two diet treatments (boiled lettuce or Spirulina, an algae that is rich in protein, vitamins, and minerals). Spirulina‐fed snails initiated reproduction at a 13% earlier age and 7% larger size than lettuce‐fed snails. Spirulina also resulted in a 30% reduction in the time delay before selfing. Compared to lettuce, a diet of Spirulina increased inbreeding depression by 52% for egg hatching rate and 64% for posthatching juvenile survival. Furthermore, Spirulina led to a 15‐fold increase in the rate of reproductive senescence compared with a diet of lettuce. These transgenerational, interactive effects of diet on inbreeding depression and reproductive senescence are discussed in the context of diet‐induced phenotypic plasticity. 相似文献
126.
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128.
Henkel C Schwamborn K Zimmermann HW Tacke F Kühnen E Odenthal M Groseclose MR Caprioli RM Weiskirchen R 《Journal of cellular and molecular medicine》2011,15(10):2176-2188
Despite tremendous efforts in disclosing the pathophysiological and epidemiological factors associated with liver fibrogenesis, non-invasive diagnostic measures to estimate the clinical outcome and progression of liver fibrogenesis are presently limited. Therefore, there is a mandatory need for methodologies allowing the reasonable and reliable assessment of the severity and/or progression of hepatic fibrogenesis. We here performed proteomic serum profiling by matrix-assisted laser desorption ionization time-of-flight mass spectrometry in 179 samples of patients chronically infected with hepatitis C virus and 195 control sera. Multidimensional analysis of spectra allowed the definition of algorithms capable to distinguish class-specific protein expression profiles in serum samples. Overall about 100 peaks could be detected per single spectrum. Different algorithms including protein peaks in the range of 2000 and 10,000 Da were generated after pre-fractionation on a weak cation exchange surface. A specificity of 93% with a sensitivity of 86% as mean of the test set results was found, respectively. The nature of three of these protein peaks that belonged to kininogen-1 and thymosin-β(4) was further analysed by tandem mass spectrometry (MS)/MS. We further found that kininogen-1 mRNA was significantly down-regulated in cirrhotic livers. We have identified kininogen-1 and thymosin-β(4) as potential new biomarkers for human chronic hepatitis C and conclude that serum profiling is a reliable technique to identify hepatitis-associated expression patterns. Based on the high throughput capability, the identified differential protein panel may serve as a diagnostic marker and warrants further validation in larger cohorts. 相似文献
129.
Sebastian Henkel Thomas N?gele Imke H?rmiller Thomas Sauter Oliver Sawodny Michael Ederer Arnd G Heyer 《EURASIP Journal on Bioinformatics and Systems Biology》2011,2011(1):2
Plant carbohydrate metabolism comprises numerous metabolite interconversions, some of which form cycles of metabolite degradation and re-synthesis and are thus referred to as futile cycles. In this study, we present a systems biology approach to analyse any possible regulatory principle that operates such futile cycles based on experimental data for sucrose (Scr) cycling in photosynthetically active leaves of the model plant Arabidopsis thaliana. Kinetic parameters of enzymatic steps in Scr cycling were identified by fitting model simulations to experimental data. A statistical analysis of the kinetic parameters and calculated flux rates allowed for estimation of the variability and supported the predictability of the model. A principal component analysis of the parameter results revealed the identifiability of the model parameters. We investigated the stability properties of Scr cycling and found that feedback inhibition of enzymes catalysing metabolite interconversions at different steps of the cycle have differential influence on stability. Applying this observation to futile cycling of Scr in leaf cells points to the enzyme hexokinase as an important regulator, while the step of Scr degradation by invertases appears subordinate. 相似文献
130.
Vaknin I Kunis G Miller O Butovsky O Bukshpan S Beers DR Henkel JS Yoles E Appel SH Schwartz M 《PloS one》2011,6(11):e26921