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Extremophiles - By applying the culturomics concept and using culture conditions containing a high salt concentration, we herein isolated the first known halophilic archaeon colonizing the human...  相似文献   
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The emergence of stretchable textile‐based mechanical energy harvester and self‐powered active sensor brings a new life for wearable functional electronics. However, single energy conversion mode and weak sensing capabilities have largely hindered their development. Here, in virtue of silver‐coated nylon yarn and silicone rubber elastomer, a highly stretchable yarn‐based triboelectric nanogenerator (TENG) with coaxial core–sheath and built‐in spring‐like spiral winding structures is designed for biomechanical energy harvesting and real‐time human‐interactive sensing. Based on the two advanced structural designs, the yarn‐based TENG can effectively harvest or respond rapidly to omnifarious external mechanical stimuli, such as compressing, stretching, bending, and twisting. With these excellent performances, the yarn‐based TENG can be used in a self‐counting skipping rope, a self‐powered gesture‐recognizing glove, and a real‐time golf scoring system. Furthermore, the yarn‐based TENG can also be woven into a large‐area energy‐harvesting fabric, which is capable of lighting up light emitting diodes (LEDs), charging a commercial capacitor, powering a smart watch, and integrating the four operational modes of TENGs together. This work provides a new direction for textile‐based multimode mechanical energy harvesters and highly sensitive self‐powered motion sensors with potential applications in sustainable power supplies, self‐powered wearable electronics, personalized motion/health monitoring, and real‐time human‐machine interactions.  相似文献   
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The main message of this review can be summarized as follows: aging and longevity, as complex traits having a significant genetic component, likely depend on a number of nuclear gene variants interacting with mtDNA variability both inherited and somatic. We reviewed the data available in the literature with particular attention to human longevity, and argued that what we hypothesize for aging and longevity could have a more general relevance and be extended to other age-related complex traits such as Alzheimer's and Parkinson's diseases. The genetics which emerges for complex traits, including aging and longevity, is thus even more complicated than previously thought, as epistatic interactions between nuclear gene polymorphisms and mtDNA variability (both somatic and inherited) as well as between mtDNA somatic mutations (tissue specific) and mtDNA inherited variants (haplogroups and sub-haplogroups) must be considered as additional players capable of explaining a part of the aging and longevity phenotype. To test this hypothesis is one of the main challenge in the genetics of aging and longevity in the next future.  相似文献   
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The paper deals with the synthesis of organic–inorganic hybrid membranes, Hy, obtained by simultaneous grafting and crosslinking of chitosan with epoxy-terminated polydimethylsiloxane and γ-glycidoxypropyltrimethoxysilane. Porous membranes, HyP, were also obtained by acid decomposition, at different temperatures (25 and 50 °C), of calcium carbonate porogenic agent trapped inside the material. As proved by electron and atomic force microscopy, the non-porous membrane is a phase segregated material with spherical domains (10–40 μm) of silica core covered by hydrophobic siloxane in a hydrophilic chitosan matrix. The porous membranes showed different morphologies with irregular circular pores of 10–30 μm diameters for the membranes obtained at lower temperature, while the membranes prepared at 50 °C tend to adopt a plan-parallel porosity. The water contact angles of hybrid membranes (78°) and pure chitosan membranes (72°) indicated a lower hydrophilic character of modified chitosan. As a result of the crosslinking and of increased hydrophobicity, the hybrid membranes were characterized by a smaller water swelling degree (about 30%) as compared to pure chitosan membrane (700%). However, the presence of the pores in HyP membranes determined an increase of the water adsorption (maximum swelling degree, about 100%). The hybrid membranes possess a slightly higher thermal stability as compared to chitosan (first initial decomposition temperature, 147 and 175 °C for chitosan and hybrid membranes, respectively), but a lower one as compared to pure polydimethylsiloxane. The high storage modulus of chitosan (about 5.1 × 109 Pa at 20 °C) is decreased by about one order of magnitude by the introduction of the highly flexible polysiloxane and the hybrid membranes are more flexible.  相似文献   
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Immunosuppressive status in solid organ transplant recipients is often related to the reactivation of Human Cytomegalovirus (HCMV) infection that remains one of the major causes of morbidity and mortality. Therefore, the early detection of HCMV followed by infection monitoring is important to institute prompt and appropriate treatment. In recent years good results have been obtained by HCMV DNA amplification methods; qualitative and quantitative approaches have shown good sensitivity and specificity, but they often require post-PCR manipulation that adds time to the analysis and may lead to contamination problems. Recently, Real Time PCR (RT-PCR) has been proposed in HCMV DNA analysis as a valid method for its good sensitivity and rapidity. In the present study, twenty-five solid organ transplant recipients were analyzed for HCMV diagnosis; 60 peripheral blood leukocytes and 120 plasma samples were tested by RT-PCR and the results compared to those obtained by a qualitative Nested PCR and a quantitative DNA enzyme immunoassay.  相似文献   
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Protective mechanisms during ischemic tolerance in skeletal muscle   总被引:3,自引:0,他引:3  
The purpose of this study was to test specific mechanisms of protection afforded the rat extensor digitorum longus (EDL) muscle during ischemic tolerance. Two days following five cycles of 10 min ischemia and 10 min reperfusion, heme oxygenase (HO) and calcium-dependent nitric oxide synthase (cNOS) activities were increased 2- and 2.5-fold (p <.05), respectively. Interestingly, calcium-independent NOS (iNOS) activity was completely downregulated (p <.05). The levels of superoxide dismutase (SOD) and catalase were increased 2-fold (p <.05), while glutathione peroxidase activity remained unchanged from non-preconditioned controls. Using intravital microscopy combined with chromium mesoporphyrin (CrMP), a selective HO inhibitor, and l-NAME, a NOS inhibitor, the roles of HO and cNOS were evaluated. Ischemic tolerance in the EDL muscle, 48 h after the preconditioning stimulus, was characterized by complete protection from both microvascular perfusion deficits and tissue injury after a 2-h period of ischemia. Removal of NOS activity completely removed the benefit afforded microvascular perfusion, while inhibition of HO activity prevented the parenchymal protection. These data suggest that ischemic tolerance within skeletal muscle is associated with the upregulation of specific cytoprotective proteins and that the benefits afforded by cNOS and HO activity are spatially discrete to the microvasculature and parenchyma, respectively.  相似文献   
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Five female workers were monitored for 5 consecutive days during re-entry into a greenhouse containing ornamental plants. Skin contamination (excluding hands) was evaluated with nine pads of filter paper placed on the skin. Hand contamination was assessed by washing with 95% ethanol. Respiratory exposure was evaluated by personal air sampling. The respiratory dose was based on a lung ventilation of 15 l/min. The doses absorbed were estimated assuming 10% skin absorption and 100% lung retention. Dislodgeable foliar residue was determined on days of re-entry to evaluate the decay of chlorothalonil. Chlorothalonil was analysed in the different matrices by GC-MS. Respiratory exposure was less than skin contamination, being 11.4+/-5.1% (mean+/-SD) of total exposure. The estimated total absorbed dose did not exceed the acceptable daily intake of 0.03 mg/kg body mass. The hands and unexposed skin of all workers were always found to be contaminated. Greater precautions are therefore needed to reduce skin exposure (clean gloves and suitable clean clothing every day).  相似文献   
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