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941.
Body condition may predict individual fitness because those in better condition have more resources to allocate towards improving their fitness. However, the hypothesis that condition indices are meaningful proxies for fitness has been questioned. Here, we ask if intraspecific variation in condition indices predicts annual reproductive success and survival. We monitored a population of Neochmia phaeton (crimson finch), a sedentary, tropical passerine, for reproductive success and survival over four breeding seasons, and sampled them for commonly used condition indices: mass adjusted for body size, muscle and fat scores, packed cell volume, hemoglobin concentration, total plasma protein, and heterophil to lymphocyte ratio. Our study population is well suited for this research because individuals forage in common areas and do not hold territories such that variation in condition between individuals is not confounded by differences in habitat quality. Furthermore, we controlled for factors that are known to impact condition indices in our study population (e.g., breeding stage) such that we assessed individual condition relative to others in the same context. Condition indices that reflect energy reserves predicted both the probability of an individual fledging young and the number of young produced that survived to independence, but only during some years. Those that were relatively heavy for their body size produced about three times more independent young compared to light individuals. That energy reserves are a meaningful predictor of reproductive success in a sedentary passerine supports the idea that energy reserves are at least sometimes predictors of fitness. However, hematological indices failed to predict reproductive success and none of the indices predicted survival. Therefore, some but not all condition indices may be informative, but because we found that most indices did not predict any component of fitness, we question the ubiquitous interpretation of condition indices as surrogates for individual quality and fitness.  相似文献   
942.
943.
The monoclonal antibody MOv19 directed to a folate binding protein shows temperature-dependent potentiation of binding of the noncompeting monoclonal antibody MOv18 to the relevant antigen, but the mechanism involved in this phinomenon had remained unclear. Use of chimeric versions of both monoclonal antibodies and the F(ab′)2 and fan fragments of MOv19 revealed an increment in MOv18 binding in all combinations irrespective of the orgin of the Fc portin of the monoclonal antibody. The potentiating effect of bivalent MOv19 fragments on 125l-MOv18 binding was similar to that of the entire monoclonal antibody and occurred at saturating concentrations of both reagents at which monovalent binding prevails. Similarly, the monovalent fragment also induced a significant increase in MOv18 bunding. Howener, the potentiation sccurred only at very high concentrations of antibody fragment. Homologous inhibition was drastically reduced using MOv19 Fab fragment, suggesting a low binding stability of the monovalent reagent. Immunoblotting analysis and binding in the presence of exogenous purified folate binding protein indicated a cross-linking between soluble and cell surface molecules mediated by the bivalent monoclonal antibodies. The extentof the increase in MOv18 binging at O°C with high amounts of exogenous folate binding protein was lower than that obtained at 370C in the absence of added molecule. Release of 125l-MOv18 from the cell surface was significantly higher in the absence of MOv19 than in its presence. Affinity constant values of 125l-MOv18 binding evaluated in the presence of MOv19 or control monoclonal antibody MINT5 were comparable, whereas the number of binding sites per cell detected by 125l-MOv18 was significantly higher in the presence of MOv19 than MINT5. Together, the data suggest that monoclonal antibody MOv19 induces a conformational change of the molecule it binds that increases the number of antigenic sites anvailable for MOv18 binding and, in turn, the binding stability of the latter, MOv19 bivalency also contributes to the MOv18 binding increment by cross-linking released and cell surface–anchored folate binding protein molecules. © Wiley-Liss, Inc.  相似文献   
944.
An overview on the use of bile acid‐based compounds able to catalyze transformations, control the stereochemical course of a given reaction, recognize and bind other molecules, is presented. The recent developments in inclusion discrimination of chiral and achiral guests and enantioselective recognition achieved by bile acid are described with suitable examples. Chirality 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
945.
946.
Kotov  Alexey A.  Boikova  Olga S. 《Hydrobiologia》2001,442(1-3):127-143
The embryonic development of Daphnia galeata and D. hyalina (`Cladocera', Anomopoda, Daphniidae) has been investigated by observing living embryos removed from female brood pouches. The sequence of morphological changes was analysed, as was the time at which the activity of certain organs began. The timing of these events at 22 °C is documented for both species.These data were compared with similar information, previously obtained for two representatives of the Ctenopoda (Kotov & Boikova, 1998). The sequence of events is basically similar in the two groups during early and late phases of their development, but the time of shedding of the embryonic membranes is different in the Anomopoda and Ctenopoda. The ctenopod embryo hatching from the second egg membrane is covered by the third membrane, which will be cast some hours later. The anomopod embryo hatches from the second egg membrane approximately simultaneously with the shedding of the third membrane, and it is covered already by the fourth membrane after the shedding of the second egg membrane.Earlier (Kotov & Boikova, 1998), we determined four embryonic instars in the course of the development of the Ctenopoda. Two of them are passed within the egg membranes, the next two instars occur after the shedding the egg membranes within the mother's brood pouch. However, in anomopods, one of the latter (the third) occurs within the second egg membrane, one is incorporated into the egg. Thus, the development of the Anomopoda is more embryonized in comparison with that of the Ctenopoda.  相似文献   
947.
Thymomas are rare neoplasms that have an indolent growth with a preferentially intra-thoracic dissemination pattern. Surgery is currently the standard treatment of thymomas; however radiotherapy is often used in an adjuvant setting due to a high sensitivity of these tumors to such treatment. Postoperative entire hemithoracic irradiation has been used in selected Masaoka stage IVa cases after complete surgical excision of metastatic lesions.In the present article, the authors report three cases of Masaoka stage IVa thymoma that underwent entire hemithorax irradiation after surgical excision of metastatic lesions. The first two patients presented as stage IVa thymomas. The third case consisted of a pleural recurrence of a thymoma.Hemithoracic irradiation with low doses has been used by different authors; the available data shows that it is a well-tolerated treatment that could potentially lead to better loco-regional control and increased overall survival.  相似文献   
948.
949.
Cells of the endocervix are responsible for the secretion of mucins, which provide an additional layer of protection to the female reproductive tract (FRT). This barrier is likely fortified with IgA as has previously been shown in the gastrointestinal tract and lungs of mice. Mucus associated IgA can facilitate clearance of bacteria. While a similar function for IgG has been proposed, an association with mucus has not yet been demonstrated. Here we find that IgA and IgG are differentially associated with the different types of mucus of the FRT. We observed that while both IgA and IgG are stably associated with cervical mucus, only IgG is associated with cervicovaginal mucus. These findings reveal that antibodies can bind tightly to mucus, where they can play a significant role in the fortification of the mucus barriers of the FRT. It may be possible to harness this interaction in the development of vaccines designed to protect the FRT mucosal barriers from sexually transmitted diseases such as HIV.  相似文献   
950.
Astrocytes are a dominant cell type that envelopes the glioma bed. Typically, that is followed by formation of contacts between astrocytes and glioma cells and accompanied by change in astrocyte phenotype, a phenomenon known as a ‘reactive astrogliosis.’ Generally considered glioma-promoting, astrocytes have many controversial peculiarities in communication with tumor cells, which need thorough examination in vitro. This review is devoted to in vitro co-culture studies of glioma cells and astrocytes. Firstly, we list several fundamental works which allow understanding the modalities of co-culturing. Cell-to-cell interactions between astrocytes and glioma cells, the roles of astrocytes in tumor metabolism, and glioma-related angiogenesis are reviewed. In the review, we also discuss communications between glioma stem cells and astrocytes. Co-cultures of glioma cells and astrocytes are used for studying anti-glioma treatment approaches. We also enumerate surgical, chemotherapeutic, and radiotherapeutic methods assessed in co-culture experiments. In conclusion, we underline collisions in the field and point out the role of the co-cultures for neurobiological studies.  相似文献   
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