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251.
Decreased antioxidant activity is considered as one of the causes of tardive dyskinesia in schizophrenic patients in a prolonged neuroleptic treatment course. Haloperidol (HAL) has been hypothesized to increase oxidative stress, while clozapine (CLO) would produce less oxidative damage. The objective was to determine whether CLO for 28 days could reverse or attenuate HAL-induced oxidative damage in animals previously treated with HAL for 28 days. HAL significantly increased thiobarbituric acid reactive substances levels in the cortex (CX) and striatum and increased protein carbonyls in hippocampus (HP) and CX and this was not attenuated by CLO treatment. In the total radical trapping antioxidant parameter assay there was a decrease in the HP total antioxidant potential induced by HAL and by treatment with HAL + CLO. Our findings demonstrated that the atypical antipsychotic CLO could not revert oxidative damage caused by HAL.  相似文献   
252.
Changes in fish densities recorded over 14 years (1996–2009) were studied for effects of long-term variation of the hydrologic regime. We collected field data with an echo sounder in scour holes of minor channels draining an area of floodplain in the middle reach of the Paraná River. Fish densities in 2000–2009 were significantly lower than in the previous decade. The decrease was associated with a marked reduction of water levels, flood magnitudes and connectivity of channels with the nearby floodplain lakes. This distortion of the flood pulse likely had an effect on the life history strategies of the fishes. The effects of damming in the upstream basin and other man-made perturbations are minor in the middle reach. However, the decadal alterations of regime are intimately linked to climate fluctuations in the Paraná River basin during the past century. Tendencies of observed fish densities are similar to results reported in literature on the influence on fishes for similar long-term alterations of the flood regime in river flood plain systems.  相似文献   
253.
The dynamic geological and climatological history of Southeast Asia has spawned a complex array of ecosystems and 12 of the 37 known cat species, making it the most felid‐rich region in the world. To examine the evolutionary histories of these poorly studied fauna, we compared phylogeography of six species (leopard cat Prionailurus bengalensis, fishing cat P. viverrinus, Asiatic golden cat Pardofelis temminckii, marbled cat P. marmorata, tiger Panthera tigris and leopard P. pardus) by sequencing over 5 kb of DNA each from 445 specimens at multiple loci of mtDNA, Y and X chromosomes. All species except the leopard displayed significant phylogenetic partitions between Indochina and Sundaland, with the central Thai–Malay Peninsula serving as the biogeographic boundary. Concordant mtDNA and nuclear DNA genealogies revealed deep Indochinese–Sundaic divergences around 2 MYA in both P. bengalensis and P. marmorata comparable to previously described interspecific distances within Felidae. The divergence coincided with serial sea level rises during the late Pliocene and early Pleistocene, and was probably reinforced by repeated isolation events associated with environmental changes throughout the Pleistocene. Indochinese–Sundaic differentiations within P. tigris and P. temminckii were more recent at 72–108 and 250–1570 kya, respectively. Overall, these results illuminate unexpected, deep vicariance events in Southeast Asian felids and provide compelling evidence of species‐level distinction between the Indochinese and Sundaic populations in the leopard cat and marbled cat. Broader sampling and further molecular and morphometric analyses of these species will be instrumental in defining conservation units and effectively preserving Southeast Asian biodiversity.  相似文献   
254.
This study focused on the distribution of fish with high reproductive activity along a basin, using a 430 km stretch of the Cuiabá River in Brazil as a model. The main objective of this study was to identify those fish that migrate long distances for reproduction, among all the basin species. Thus, a set of working criteria are proposed to classify species according to their reproductive behaviour (i.e., reproductive activity and distribution). Samplings were performed in the Cuiabá River basin, encompassing several environments (river, channels and lakes) during the reproductive periods (between October and February), from 2000 to 2004. Species occurrence (presence and absence – proxy of distribution) across the basin and index of reproductive activity values were used as criteria to identify the species that perform long-distance longitudinal migrations for reproduction. The study confirmed the classification of long-distance longitudinal migration species; nonetheless, some species were not classified as described in the literature. The proposed sequential criteria have proven to be effective in the classification of long-distance longitudinal migrations species and certainly contribute to filling some existing knowledge gaps of reproductive traits. This classification is of fundamental importance in planning new dam projects, in decision making and in the development of management and conservation actions for the ichthyofauna.  相似文献   
255.
The mortality of Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae and Pseudomonas aeruginosa, based on the culturability of these bacteria, was assessed in non-carbonated mineral water, bottled in polyvinyl chloride (PVC) containing the indigenous flora, sterile mineral water bottled in PVC, sterile mineral water in glass containers, and sterile tap water in glass containers. There was a general decrease in the culturability of these organisms in the four test waters, except that Ps. aeruginosa grew in sterile tap water. Escherichia coli and Kl. pneumoniae had the highest mortality rates under the conditions tested, while Ent. cloacae had a very low and constant mortality rate that would have resulted in the persistence of this organism in mineral water for a long period of time. After a sharp initial decrease in culturability, Ps. aeruginosa also had a very low mortality rate in mineral water bottled in PVC.  相似文献   
256.
In this preliminary study defense behaviour patterns (fear responses) are described in two closely related, behaviourally different inbred labyrinth fish subspecies and in their F1 generation. The subspecies M. opercularis (characterized briefly by “active escape”) and M. opercularis concolor (characterized by “passive escape”) showed specific differences in the manifestation of certain defense behaviour patterns. In the F1 hybrid generation dominance and overdominance of M. opercularis was found in most defense behaviour patterns. Analysing the frequencies and sequences of movement patterns it could be shown that defensive behaviour is not a random or entirely “plastic” process but that there is sequential linkage between the patterns and they form characteristic clusters. Our results suggest that manifestations of different patterns are under genetic control and presumably, genetic determination of certain patterns is not very complex. Attempts were made to determine whole brain noradrenaline, serotonine and dopamine levels of the two subspecies and a significant difference was found in the noradrenaline content.  相似文献   
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