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181.
Abstract: The fauna of false fairy wasps (Proctotrupomorpha: Bipetiolarida: Mymarommatoidea) occurring in Early Cretaceous (Albian) amber from north and north‐eastern Spain (Moraza, San Just, and El Soplao outcrops) is described. In total, 12 specimens have been recovered and four species recognized, all new: Alavaromma orchamum gen. nov. and sp. nov. (Alavarommatidae fam. nov.), Archaeromma hispanicum sp. nov. (Mymarommatidae), Galloromma alavaensis sp. nov., and G. turolensis sp. nov. (Gallorommatidae). The study indicates the necessity of revision and maybe fusion of both superfamilies, Mymarommatoidea and Serphitoidea, as the boundaries between them are less and less defined. However, major classificatory rearrangements must await the completion of the cladistic studies presently underway.  相似文献   
182.
For species at risk, it is important that demographic models be consistent with our most recent knowledge because alternate model versions can have differing predictions for wildlife and natural resource management. To establish and maintain this consistency, we can compare predicted model values to current or past observations and demographic knowledge. When novel predictor information becomes available, testing for consistency between modeled and observed values ensures the best models are used for robust, evidence-based, wildlife management. We combine novel information on the extent of historical disturbance regimes (industrial and fire) to an existing demographic model and predict historical and projected demographics of woodland caribou (Rangifer tarandus caribou). Exploring 6 simulation experiments across 5 populations in Alberta, Canada, we identify the relative importance of industrial disturbance, fire, and population density to observed population size and growth rate. We confirm the onset of significant declines across all 5 populations began approximately 30 years ago, demonstrate these declines have been consistent, and conclude they are more likely due to industrial disturbance from the oil and gas sector within contemporary population ranges than historical fire regimes. These findings reinforce recent research on the cause of woodland caribou declines. Testing for consistency between observations and models prescribed for species recovery is paramount for assessing the cause of declines, projecting population trends, and refining recovery strategies for effective wildlife management. We provide a novel simulation method for conducting these tests. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society.  相似文献   
183.
The CRF (corticotropin‐releasing factor) system is a key mediator of the stress response. Alterations in CRF signaling have been implicated in drug craving and ethanol consumption. The development of negative reinforcement via activation of brain stress systems has been proposed as a mechanism that contributes to alcohol dependence. Here, we isolated a gain‐of‐function allele of seb‐3, a CRF receptor‐like GPCR in Caenorhabditis elegans, providing an in vivo model of a constitutively activated stress system. We also characterized a loss‐of‐function allele of seb‐3 and showed that SEB‐3 positively regulates a stress response that leads to an enhanced active state of locomotion, behavioral arousal and tremor. SEB‐3 also contributed to acute tolerance to ethanol and to the development of tremor during ethanol withdrawal. Furthermore, we found that a specific CRF1 receptor antagonist reduced acute functional tolerance to ethanol in mice. These findings demonstrate functional conservation of the CRF system in responses to stress and ethanol in vertebrates and invertebrates.  相似文献   
184.
Transition metals such as copper can interact with ascorbate or hydrogen peroxide to form highly reactive hydroxyl radicals (OH?), with numerous implications to membrane transport activity and cell metabolism. So far, such interaction was described for extracellular (apoplastic) space but not cytosol. Here, a range of advanced electrophysiological and imaging techniques were applied to Arabidopsis thaliana plants differing in their copper‐transport activity: Col‐0, high‐affinity copper transporter COPT1‐overexpressing (C1OE) seedlings, and T‐DNA COPT1 insertion mutant (copt1). Low Cu concentrations (10 µm ) stimulated a dose‐dependent Gd3+ and verapamil sensitive net Ca2+ influx in the root apex but not in mature zone. C1OE also showed a fivefold higher Cu‐induced K+ efflux at the root tip level compared with Col‐0, and a reduction in basal peroxide accumulation at the root tip after copper exposure. Copper caused membrane disruptions of the root apex in C1OE seedlings but not in copt1 plants; this damage was prevented by pretreatment with Gd3+. Our results suggest that copper transport into cytosol in root apex results in hydroxyl radical generation at the cytosolic side, with a consequent regulation of plasma membrane OH?‐sensitive Ca2+ and K+ transport systems.  相似文献   
185.
Coupons of fourteen different stainless steels were investigated in terms of surface chemistry and ease of cleaning. Steel surfaces were exposed to Bacillus cereus spores in static saline solution for 2?h. Surfaces were rinsed and then covered with whole milk and allowed to dry. Surfaces were then cleaned in an experimental flow system that mimics an industrial application. After cleaning, remaining spores were released by sonication, spores cultured and colony forming units determined. Surfaces with higher levels of Fe in the outer surface of the passive film cleaned more easily. There was a relation between the polar component and ease of cleaning. The higher the polar component the more easily the surface cleaned. The cleaning mechanism involves dissolution of Fe enriched hydroxide films on the surface.  相似文献   
186.
Laser photocoagulation induced choroidal neovascularization currently is the most effective model available for the study of this disease in terms of efficacy of new drugs and therapies. Previously, evaluating the extent of choroidal neovascularization using this model was time- consuming and required the use of experienced personnel. We describe a new method for simple and rapid evaluation of laser induced choroidal neovascularization using densitometry. Fluorescein angiograms of a laser photocoagulated rat eye were scanned into a computer. Densitometry software subsequently was used to calculate the severity of the laser lesions. The densitometry method proved effective for calculating the extent of laser induced choroidal neovascularization. In addition, this method was more rapid than visual evaluations and less likely to produce errors.  相似文献   
187.
The nucleotide sequence of the methylamine utilization (mau) gene region from Methylobacterium extorquens AM1 was determined. Open reading frames for 11 genes (mauFBEDACJGLMN) were found, all transcribed in the same orientation. The mauB, mauA, and mauC genes encode the periplasmic methylamine dehydrogenase (MADH) large and small subunit polypeptides and amicyanin, respectively. The products of mauD, mauG, mauL, and mauM were also predicted to be periplasmic. The products of mauF, mauE, and mauN were predicted to be membrane associated. The mauJ product is the only polypeptide encoded by the mau gene cluster which is predicted to be cytoplasmic. Computer analysis showed that the MauG polypeptide contains two putative heme binding sites and that the MauM and MauN polypeptides have four and two FeS cluster signatures, respectively. Mutants generated by insertions in mauF, mauB, mauE, mauD, mauA, mauG, and mauL were not able to grow on methylamine or any other primary amine as carbon sources, while a mutant generated from an insertion in mauC was not able to utilize methylamine as a source of carbon but utilized C2 to C4 n-alkylamines as carbon sources. Insertion mutations in mauJ, mauM, and mauN did not impair the ability of the mutants to utilize primary n-alkylamines as carbon sources. All mau mutants were able to utilize methylamine as a nitrogen source, implying the existence of an alternative (methyl)amine oxidation system, and a low activity of N-methylglutamate dehydrogenase was detected. The mauD, mauE, and mauF mutants were found to lack the MADH small subunit polypeptide and have a decreased amount of the MADH large subunit polypeptide. In the mauG and mauL mutants, the MADH large and small subunit polypeptides were present at wild-type levels, although the MADHs in these strains were not functional. In addition, MauG has sequence similarity to cytochrome c peroxidase from Pseudomonas sp. The mauA, mauD, and mauE genes from Paracoccus denitrificans and the mauD and mauG genes from Methylophilus methylotrophus W3A1 were able to complement corresponding mutants of M. extorquens AM1, confirming their functional equivalence. Comparison of amino acid sequences of polypeptides encoded by mau genes from M. extorquens AM1, P. denitrificans, and Thiobacillus versutus shows that they have considerable similarity.  相似文献   
188.
Laser photocoagulation induced choroidal neovascularization currently is the most effective model available for the study of this disease in terms of efficacy of new drugs and therapies. Previously, evaluating the extent of choroidal neovascularization using this model was time- consuming and required the use of experienced personnel. We describe a new method for simple and rapid evaluation of laser induced choroidal neovascularization using densitometry. Fluorescein angiograms of a laser photocoagulated rat eye were scanned into a computer. Densitometry software subsequently was used to calculate the severity of the laser lesions. The densitometry method proved effective for calculating the extent of laser induced choroidal neovascularization. In addition, this method was more rapid than visual evaluations and less likely to produce errors.  相似文献   
189.
Crater Lake is a unique environment to evaluate the ecology of introduced kokanee and rainbow trout because of its otherwise pristine state, low productivity, absence of manipulative management, and lack of lotic systems for fish spawning. Between 1986 and 2004, kokanee displayed a great deal of variation in population demographics with a pattern that reoccurred in about 10 years. We believe that the reoccurring pattern resulted from density dependent growth, and associated changes in reproduction and abundance, driven by prey resource limitation that resulted from low lake productivity exacerbated by prey consumption when kokanee were abundant. Kokanee fed primarily on small-bodied prey from the mid-water column; whereas rainbow trout fed on large-bodied prey from the benthos and lake surface. Cladoceran zooplankton abundance may be regulated by kokanee. And kokanee growth and reproductive success may be influenced by the availability of Daphnia pulicaria, which was absent in zooplankton samples collected annually from 1990 to 1995, and after 1999. Distribution and diel migration of kokanee varied over the duration of the study and appeared to be most closely associated with prey availability, maximization of bioenergetic efficiency, and fish density. Rainbow trout were less abundant than were kokanee and exhibited less variation in population demographics, distribution, and food habits. There is some evidence that the population dynamics of rainbow trout were in-part related to the availability of kokanee as prey.  相似文献   
190.
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