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71.
Yee  KK; Costanzo  RM 《Chemical senses》1998,23(5):513-519
Following recovery from olfactory nerve transection, animals regain their ability to discriminate between odors. Odor discrimination is restored after new neurons establish connections with the olfactory bulb. However, it is not known if the new connections alter odor quality perception. To address this question, 20 adult hamsters were first trained to discriminate between cinnamon and strawberry odors. After reaching criterion (> or = 90% correct response), half of the animals received a bilateral nerve transection (BTX) and half a surgical sham procedure. Animals were not tested again until day 40, a point in recovery when connections are re-established with the bulb. When BTX animals were tested without food reinforcement, they could not perform the odor discrimination task. Sham animals, however, could discriminate, demonstrating that the behavioral response had not been extinguished during the 40 day period. When reinforcement was resumed, BTX animals were able to discriminate between cinnamon and strawberry after four test sessions. In addition, their ability to discriminate between these two familiar odors was no different than that of BTX and sham animals tested with two novel odors, baby powder and coffee. These findings suggest that, after recovery from nerve transection, there are alterations in sensory perception and that restoration of odor quality discrimination requires that the animal must again learn to associate individual odor sensations with a behavioral response.   相似文献   
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Here, we investigated which stress responses were influenced by the MpkC and SakA mitogen‐activated protein kinases of the high‐osmolarity glycerol (HOG) pathway in the fungal pathogen Aspergillus fumigatus. The ΔsakA and the double ΔmpkC ΔsakA mutants were more sensitive to osmotic and oxidative stresses, and to cell wall damaging agents. Both MpkC::GFP and SakA::GFP translocated to the nucleus upon osmotic stress and cell wall damage, with SakA::GFP showing a quicker response. The phosphorylation state of MpkA was determined post exposure to high concentrations of congo red and Sorbitol. In the wild‐type strain, MpkA phosphorylation levels progressively increased in both treatments. In contrast, the ΔsakA mutant had reduced MpkA phosphorylation, and surprisingly, the double ΔmpkC ΔsakA had no detectable MpkA phosphorylation. A. fumigatus ΔsakA and ΔmpkC were virulent in mouse survival experiments, but they had a 40% reduction in fungal burden. In contrast, the ΔmpkC ΔsakA double mutant showed highly attenuated virulence, with approximately 50% mice surviving and a 75% reduction in fungal burden. We propose that both cell wall integrity (CWI) and HOG pathways collaborate, and that MpkC could act by modulating SakA activity upon exposure to several types of stresses and during CW biosynthesis.  相似文献   
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The conditions of storage, cultivation and maintenance of microbial cultures should preserve the microbiological homogeneity, phenotypic and genotypic characteristics to ensure better reproducibility of metabolic production. To evaluate the influence of the storage condition on the composition of cell fatty acids, genetic profile and biochemical characteristics of Xanthomonas campestris pv. mangiferaeindicae IBSBF 2103, as well as, to identify its relationship with the yielding and viscosity of the xanthan gum produced, this study monitored the strain preserved in two simple and widely used conditions, ultra-freezer (?80 °C) and refrigeration (3–8 °C) during 5 months. Were identified and quantified 13 fatty acids. The cells preserved at ?80 °C showed more stable concentration of all fatty acids, producing more xanthan gum and with higher viscosity. The chromosomal analysis obtained with the enzyme XbaI revealed 17 distinct fragments with maximum size of 485 kilobases, without variations among the subcultures maintained in both storage conditions. The X. campestris pv. mangiferaeindicae subcultures preserved at ?80 °C showed less pronounced phenotypic variations, which had positive influence in the qualitative and quantitative characteristics of the xanthan gum produced.  相似文献   
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Alterations in the hydrologic regime downstream from hydroelectric dams create a high invasibility to non-native species. This study aims to analyze the establishment of non-native Metynnis lippincottianus downstream of the Xingó Dam, lower São Francisco River, Brazil. Adults in reproduction were found throughout the study. Gonadosomatic index was higher in the reproductive phases and the species produces a large number of small oocytes. Hydrometric level and water flow data after the construction of Xingó Dam showed decrease in both parameters, facilitating the establishment of M. lippincottianus. Management actions are suggested to reduce the threat on the native biota.  相似文献   
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This study dealt with six species of Acalyphoideae and 18 species of Euphorbioideae occurring in the Caatinga ecoregion, with emphasis on endemic species. Pollen samples were obtained from herbarium specimens and were acetolysed and analysed via light and scanning electron microscopy. The pollen of three genera of Acalyphoideae was medium to large, 3-colporate or 3-colpate, with an echinate-perforate exine that was reticulate, bireticulate, and microreticulate. The six genera of Euphorbioideae studied exhibited pollen grains that were small, medium and large; 3-colporate with margines; and an exine with microreticulate, microreticulate-rugulate, microreticulate-caveate, and reticulate ornamentation. The pollen characteristics were more variable in the Acalyphoideae compared to the relatively homogeneous Euphorbioideae. This study provides new data and interpretations of the pollen morphology of two subfamilies of the Euphorbiaceae of the Caatinga ecoregion in Brazil.  相似文献   
80.

Background

The current concept of overweight/obesity is most likely related to a combination of increased caloric intake and decreased energy expenditure. Widespread inflammation, associated with both conditions, appears to contribute to the development of some obesity-related comorbidities. Interventions that directly or indirectly target individuals at high risk of developing obesity have been largely proposed because of the increasing number of overweight/obese cases worldwide. The aim of the present study was to assess CXCL16, IL-17, and BMP-2 plasma factors in middle-aged and elderly women and relate them to an overweight or obese status. In total, 117 women were selected and grouped as eutrophic, overweight, and obese, according to anthropometric parameters. Analyses of anthropometric and circulating biochemical parameters were followed by plasma immunoassays for CXCL-16, IL-17, and BMP-2.

Results

Plasma mediators increased in all overweight and obese individuals, with the exception of BMP-2 in the elderly group, whereas CXCL16 levels were shown to differentiate overweight and obese individuals. Overweight and/or obese middle-aged and elderly individuals presented with high LDL, triglycerides, and glycemia levels. Anthropometric parameters indicating increased-cardiovascular risk were positively correlated with CXCL-16, BMP-2, and IL-17 levels in overweight and obese middle-aged and elderly individuals.

Conclusion

This study provides evidence that CXCL-16, IL-17, and BMP-2 are potential plasma indicators of inflammatory status in middle-aged and elderly women; therefore, further investigation of obesity-related comorbidities is recommended. CXCL16, in particular, could be a potential marker for middle-aged and elderly individuals transitioning from eutrophic to overweight body types, which represents an asymptomatic and dangerous condition.
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