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681.
Applied Microbiology and Biotechnology - Two plant-originated C-glucosyltransferases (CGTs) UGT708D1 from Glycine max and GtUF6CGT1 from Gentiana triflora were accessed for glucosylation of...  相似文献   
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Despite the severe threats to plant habitats and high levels of extinction risk for plant species in many parts of the world, plant conservation priorities are often poorly represented in national and global frameworks because of a lack of data in an accessible and consistent format to inform conservation decision making. The Important Plant Areas (IPAs) criteria system offers a pragmatic yet scientifically rigorous means of delivering these datasets, enabling informed national- or regional-scale conservation prioritisation, and contributing significantly towards global prioritisation systems including the International Union for Conservation of Nature Key Biodiversity Areas (KBAs) Standard. In this paper, we review the IPA rationale and progress on IPA identification to date, including the perceived limitations of the process and how these may be overcome. We then present a revised set of criteria for use globally, developed through the combined experiences of IPA identification over the past decade and a half and through a recent global consultation process. An overview of how the revised IPA criteria can work alongside the newly published KBA Standard is also provided. IPA criteria are based around a sound, scientific, global framework which acknowledges the practical problems of gathering plant and habitat data in many regions of the world, and recognises the role of peer reviewed expert opinion in the selection process. National and sub-national engagement in IPA identification is essential, providing a primary route towards long term conservation of key sites for plant diversity. The IPA criteria can be applied to the conservation of all organism groups within the plant and fungal kingdoms.  相似文献   
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A balance between production and degradation of reactive oxygen species (ROS) is critical for maintaining cellular homeostasis. Increased levels of ROS during oxidative stress are associated with disease conditions. Antioxidant enzymes, such as extracellular superoxide dismutase (EC-SOD), in the extracellular matrix (ECM) neutralize the toxicity of superoxide. Recent studies have emphasized the importance of EC-SOD in protecting the brain, lungs, and other tissues from oxidative stress. Therefore, EC-SOD would be an excellent therapeutic drug for treatment of diseases caused by oxidative stress. We cloned both the full length (residues 1–240) and truncated (residues 19–240) forms of human EC-SOD (hEC-SOD) into the donor plasmid pFastBacHTb. After transposition, the bacmid was transfected into the Sf9-baculovirus expression system and the expressed hEC-SOD purified using FLAG-tag. Western blot analysis revealed that hEC-SOD is present both as a monomer (33 kDa) and a dimer (66 kDa), as detected by the FLAG antibody. A water-soluble tetrazolium (WST-1) assay showed that both full length and truncated hEC-SOD proteins were enzymatically active. We showed that a potent superoxide dismutase inhibitor, diethyldithiocarbamate (DDC), inhibits hEC-SOD activity.  相似文献   
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C4 photosynthesis is thought to be an adaptation to warm environments, involving complex changes in the expression of genes governing photosynthesis, intermediary metabolism, and leaf anatomy and histology. Such complexity should be difficult to evolve, yet the pathway has arisen multiple times in the history of the flowering plants and at least four times in the grass family alone. We have used immunolocalization techniques to compare photosynthetic gene expression across all four origins, to determine which genetic changes occur in parallel and which are unique to a particular lineage. The only gene expression patterns common to all origins of the pathway are up-regulation of PEP carboxylase and down-regulation of RuBisCO in mesophyll cells. Both NAD-malic enzyme and NADP-malic enzyme are expressed in bundle sheaths. Expression patterns of light-harvesting chlorophyll a/b binding proteins and pyruvate orthophosphate dikinase appear to be lineage specific, and may be localized to bundle sheaths or to mesophyll or expressed throughout the photosynthetic tissue of the leaf. We suggest that future studies of parallel origin of the C4 pathway concentrate on regulation of the two carboxylases, as well as the increased density of vascular tissue, which is the only histological characteristic common to all origins of the pathway.  相似文献   
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Establishment of growth factor-dependent MOPC 104E cell line in vitro   总被引:1,自引:0,他引:1  
The MOPC 104E cell line has been adapted to grow in vitro using a combination of feeder layer and growth factor(s). The growth of this myeloma cell line is dependent on the presence of growth factor(s). Growth-promoting activity generated from T-cell-mitogen-stimulated, Corynebacterium parvum-stimulated spleen cell culture supernatant, and peritoneal adherent cell culture supernatants gives dose-dependent proliferation. Generation of growth factors in the serum-free bovine serum albumin-substituted media and a rapid assay system based on [3H]thymidine uptake for the quantitation of growth promoting activity are described.  相似文献   
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A method of assessing body condition of Asian elephants (Elephas maximus) is presented. The method uses visual assessment to assign numerical scores to six different regions of the body, which are totaled to give a numerical index ranging from 0–11. The relationship between the index and morphometric variables is compared for a sample of 119 juvenile and young adult elephants from southern India, Nepal, and Myanmar. Mean ages of males and females were similar. Mean index of body condition (with standard error [SE]) was 7.3±0.2 points. No significant correlation was found between index of body condition and age over both sexes (r=0.01, n=50). Results were equivalent when sexes were treated separately (females: r=0.03, n=24; males: r=0.01, n=26). Sexes did not differ in height of the shoulder or body condition in our sample, but there was significant sexual dimorphism in breadth of the zygomatic arch and three measures of subcutaneous fat: girth of neck, thickness of cervical fold, and thickness of anal flap. These three measures were also significantly correlated with each other. Our assessment method should prove a practical tool for ecologic studies, but the relationship of the index to percentage of body fat should be determined using heavy water dilution methodology. Zoo Biol 25:187–200, 2006. © 2006 Wiley‐Liss, Inc.  相似文献   
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During five years of birth season fieldwork, we observed two births and three peri-birth instances of behavior of free-ranging rhesus living in Kathmandu, Nepal. These constitute the first two recorded free-ranging rhesus births, and we compare them to the behavior which has been observed in captivity and expected in the wild. The free-ranging parturition behavior was characterized by a general lack of contact with other troop members and by overall inconspicuousness. In the first birth we observed, the troop moved about 70 m up the hill, leaving the laboring female behind on an open hillside. Two males, a female and a juvenile returned and rested about 20 m from the delivering female. During the second delivery, the female stayed with the troop and seemed to participate normally in most troop interactions, although she avoided physical contact with other troop members. We propose that this near-normal behavior may help to assure successful parturition by allowing the female the needed social isolation and inconspicuousness without any loss of troop protection. It may also partly explain why births have not been observed during previous studies. Observations of rhesus parturition behavior reported from studies of captive monkeys and reports from other free-ranging primate studies are compared with our data.  相似文献   
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