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Camouflage conceals animals from predators and depends on the interplay between the morphology and behaviour of animals. Behavioural elements of animals, such as the choice of a resting spot or posture, are important for effective camouflage, as well as the animals’ cryptic appearance. To date, the type of sensory input that mediates resting site choice remains poorly understood. Previously, we showed that bark‐like moths perceive and rely on bark structure to seek out cryptic resting positions and body orientations on tree trunks. In the present study, we investigated the sensory organs through which moths perceive the structure of bark when positioning their bodies in adaptive resting orientations. We amputated (or blocked) each one of the hypothetical sensory organs in moths (antennae, forelegs, wings, and eyes) and tested whether they were still able to perceive bark structure properly and adopt adaptive resting orientations. We found that visual information or stimulation is crucial for adaptively orienting their bodies when resting and tactile information from wings may play an additional role. The present study reveals multimodal information use by moths to achieve visual camouflage and highlights the sensory mechanism that is responsible for the adaptive behaviour of cryptic insects. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 900–904.  相似文献   
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Purpose

Medical professionals’ practices and knowledge regarding cancer pain management have often been cited as inadequate. This study aimed to evaluate knowledge, practices and perceived barriers regarding cancer pain management among physicians and nurses in Korea.

Methods

A nationwide questionnaire survey was administered to physicians and nurses involved in the care of cancer patients. Questionnaire items covered pain assessment and documentation practices, knowledge regarding cancer pain management, the perceived barriers to cancer pain control, and processes perceived as the major causes of delay in opioid administration.

Results

A total of 333 questionnaires (149 physicians and 284 nurses) were analyzed. Nurses performed pain assessment and documentation more regularly than physicians did. Although physicians had better knowledge of pain management than did nurses, both groups lacked knowledge regarding the side effects and pharmacology of opioids. Physicians working in the palliative care ward and nurses who had received pain management education obtained higher scores on knowledge. Physicians perceived patients’ reluctance to take opioids as a barrier to pain control, more so than did nurses, while nurses perceived patients’ tendency to under-report of pain as a barrier, more so than did physicians. Physicians and nurses held different perceptions regarding major cause of delay during opioid administration.

Conclusions

There were differences between physicians and nurses in knowledge and practices for cancer pain management. An effective educational strategy for cancer pain management is needed in order to improve medical professionals’ knowledge and clinical practices.  相似文献   
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We have investigated the wound-healing effects of mesenchymal stem cells (MSCs) in combination with human amniotic membrane (HAM) when grafted into full-thickness skin defects of rabbits. Five defects in each of four groups were respectively treated with HAM loaded with autologous MSCs (group A), HAM loaded with allologous MSCs (group B), HAM with injected autologous MSCs (group C), and HAM with injected allologous MSCs (group D). The size of the wounds was calculated for each group at 7, 12, and 15 days after grafting. The wounds were subsequently harvested at 25 days after grafting. Sections stained with hematoxylin and eosin were used to determine the quality of wound healing, as based on the characteristics and amount of granulated tissue in the epidermal and dermal layers. Groups A and B showed the most pronounced effect on wound closure, with statistically significant improvement in wound healing being seen on post-operative days 7, 12, and 15. Although a slight trend toward improved wound healing was seen in group A compared with group B, no statistically significant difference was found at any time point between the two groups. Histological examination of healed wounds from groups A and B showed a thin epidermis with mature differentiation and collagen bundle deposition plus recovered skin appendages in the dermal layer. In contrast, groups C and D showed thickened epidermis with immature epithelial cells and increased fibroblast proliferation with only partially recovered skin appendages in the dermal layer. Thus, the graft of HAM loaded with MSCs played an effective role during the healing of skin defects in rabbits, with no significant difference being observed in wound healing between autologous and allologous MSC transplantation. This study was supported by research funds from Dong-A University.  相似文献   
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One-carbon feedstock such as methanol and formate has attracted much attention as carbon substrate of industrial biotechnology for production of value-added chemicals and biofuels. Productivity improvement of natural one-carbon metabolic pathways in native hosts such as methanotrophs is somewhat difficult due to inefficient genetic tools and low specific growth rate. As an alternative, metabolic engineering can create new and efficient metabolic pathways of one-carbon substrate that can be readily transferred to non-native hosts. In this paper, recent progresses in protein and metabolic engineering for creation of methanol and formate-utilizing synthetic pathways based on RuMP cycle and formolase are reviewed. Perspectives on one-carbon metabolic pathway engineering in non-native host are also discussed.  相似文献   
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Harnessing the isolated protein synthesis machinery, cell‐free protein synthesis reproduces the cellular process of decoding genetic information in artificially controlled environments. More often than not, however, generation of functional proteins requires more than simple translation of genetic sequences. For instance, many of the industrially important enzymes require non‐protein prosthetic groups for biological activity. Herein, we report the complete cell‐free biogenesis of a heme prosthetic group and its integration with concurrent apoenzyme synthesis for the production of functional P450 monooxygenase. Step reactions required for the syntheses of apoenzyme and the prosthetic group have been designed so that these two separate pathways take place in the same reaction mixture, being insulated from each other. Combined pathways for the synthesis of functional P450 monooxygenase were then further integrated with in situ assay reactions to enable real‐time measurement of enzymatic activity during its synthesis. Biotechnol. Bioeng. 2013; 110: 1193–1200. © 2012 Wiley Periodicals, Inc.  相似文献   
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An enantioconvergent biotransformation of racemic styrene oxide by using two recombinant microbial epoxide hydrolases (EHs) in one pot has been investigated to prepare enantiopure vicinal diols. The recombinant whole cell possessing EH gene from Aspergillus niger LK or Rhodotorula glutinis exhibited a complementary enantioselectivity and regioselectivity, compared to the recombinant cell containing Caulobacter crescentus EH gene. When two recombinant microbial EHs were used in combination, 1.3 g of enantiopure (R)-1,2-phenylethandiol with more than 90% enantiopurity and 95% overall yield was obtained from 1.2 g of racemic styrene oxide in a preparative-scale batch enantioconvergent biotransformation.  相似文献   
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