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681.
How does temperature affect splicing events? Isoform switching of splicing factors regulates splicing of LATE ELONGATED HYPOCOTYL (LHY) 下载免费PDF全文
682.
Anders Fomsgaard Michaela C. Müller-Trutwin Ousmane Diop Jan Hansen Christian Mathiot Sylvie Corbet Francoise Barr-Sinoussi Jonathan S. Allan 《Journal of medical primatology》1997,26(3):120-128
Abstract: An apparent species-specific relatedness of SIVagm suggests a coevolution with their natural hosts. However, the exact species or subspecies classification of African green monkeys, AGM, is uncertain because current classification schemes rely on phenotype markers, while more definitive genetic data are lacking. In this study, the CD4 protein involved in tissue type recognition was genetically cloned and sequenced from PBMC RNA from all AGM species, including Barbados green monkeys (BGM). Phylogenetic trees were constructed that also included genomic CD4 nucleotide sequences from patas, sooty mangabeys, rhesus and pig-tail macaques, chimpanzees, and humans. Chimpanzees and humans consistently clustered together. Monkeys within the Cercopithecus genus formed a separate cluster which included pata monkeys, supporting its grouping as a member of Cercopithecus. Surprisingly, sooty mangabeys were genetically more closely related to Asian macaques than to other African species, which might explain why macaques are more susceptible to infection by the SIVsm group than to infection by SIVagm or HIV-1 and why patas, on the other hand, are highly susceptible to SIVagm infection. Based on CD4 genetic data, tantalus, vervets, grivets, and sabaeus formed separate subgroups with BGM grouping closely with vervets. The branching order of the AGM species was related to that of their respective SIVagm env sequences. The study suggests a strong correlation between CD4 phylogeny and the susceptibility of the host species to infection by a specific lentivirus and supports the assumption of a coevolution of SIVagm and AGM. CD4 sequencing is suggested as a relevant method for genetic determination of primate species. 相似文献
683.
The use of AFLPs to examine genetic relatedness in barley 总被引:7,自引:0,他引:7
Ellis Roger P. McNicol James W. Baird Eileen Booth Allan Lawrence Pat Thomas Bill Powell Wayne 《Molecular breeding : new strategies in plant improvement》1997,3(5):359-369
The generation of AFLPs in spring barley cultivars provided genetic information relating to the development of the crop in the UK since 1953. Principal co-ordinate (PCO) analysis of genetic similarities (gs) confirmed the marked contrast in the cultivars used in the 1970s and 1980s. The earliest cultivars, many derived from Proctor, were succeeded by tall-strawed, disease-resistant types with high yield but poor malting potential. In the 1980s they were in turn replaced by short-strawed cultivars with excellent yield and good malting quality, which originated from Triumph. A PCO plot of gs provided insight into the effects of selection for disease resistance and the antagonism between malting quality and particular resistance genes. The analysis of gs was more useful than pedigrees and estimates of kinship in revealing the genetic relationship between cultivars. Theoretical considerations for maximising the efficiency of an AFLP genotyping programme are discussed in the context of the number of primer pairs required to distinguish genotypes at varying levels of similarity. 相似文献
684.
The ribosomal protein 3 gene is differentially expressed in hypothalamus and brown adipose tissue between mouse lines divergently selected for heat loss, and in skeletal muscle of the ob/ob mouse model. Unfortunately, multiple Rpl3-processed pseudogenes have hampered mapping of the functional gene copy in mammalian species. Using PCR amplification with intronic primer binding, we have mapped Rpl3 to MMU15, and have also localized RPL3 to BTA5 in cattle. Comparative mapping implicates a previously mapped copy of RPL3 on HSA22 as the functional copy of human RPL3, while predictive mapping places the porcine homologue on SSC5. 相似文献
685.
Pristhesancus plagipennis (Walker) is a predator of larvae and nymphs of many pestiferous insects for which natural enemies are not commercially available. This paper describes a containerized mass-rearing method for P. plagipennis using hot water-killed larvae of Tenebrio molitor (L.) and Helicoverpa armigera (Hübner). In addition, the effect of P. plagipennis density during nymphal rearing and adult oviposition was investigated. The rearing method minimizes P. plagipennis cannibalism, avoids the need for live insect prey, and is space and labor efficient. Larvae of the yellow mealworm, T. molitor, were the most suitable prey for minimizing nymphal development time and mortality while producing insects with the highest body weight. When reared on a diet of T. molitor, the optimum rearing density was 20–27 nymphs per 5-liter container. This rearing density minimized nymphal mortality to 16–22%. The optimum density for oviposition was 16 adults per 5-liter container, which provided the best compromise between egg production and space utilization. 相似文献
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BACKGROUND: The vaginal vault smear is a test for cellular atypia in women who have undergone a hysterectomy. In asymptomatic women the test has poor sensitivity and specificity. Current guidelines recommend: vault smears should not be used after hysterectomy for benign pathology; two vault smears (6 and 12 months postsurgery) should be taken when there is evidence of completely excised CIN II/III in the specimen. AIM: To describe primary health care professionals' self-reported knowledge and behaviour relating to the use of vault smears. DESIGN OF STUDY: Questionnaire. SETTING: South Birmingham. METHODS: Postal questionnaire survey to primary health care professionals (general practitioners and practice nurses, n = 424). Results: Response rate 80.0%, completed response rate 68.9%. Mean knowledge score was 7.3 out of possible 12 (SD 1.9); range 0-10. No significant differences were observed between GPs and practice nurses in knowledge scores, although differences were noted in the frequency of performing vault smears. An inverse relationship was observed between frequency of performing vault smears and level of knowledge about the test. There was a positive association between requesting further information and the 'knowledge score'. Only 11% correctly answered a question based on current guidelines. CONCLUSIONS: Knowledge of current guidelines was poor. Those who undertook fewest vault smears appeared best informed. This suggests that if all primary care professionals practised according to current guidelines, the number of vault smears performed may be reduced. Unnecessary vault smears may cause additional anxiety in women and have financial consequences for the NHS. 相似文献
690.
Summary Landholder adoption of conservation practices has been extensively researched in dryland areas, but there has been less research into the adoption of biodiversity conservation practices in irrigation areas. The Murray Catchment Management Authority (MCMA) and Murray Irrigation Limited (MIL) in south‐west New South Wales offer landholders monetary incentives to enhance native vegetation management. However, uptake of the incentives and recommended practices has been slower in the irrigation areas than in dryland areas serviced by the MCMA. We explored landholder participation in native vegetation management in the MIL area using semistructured interviews with landholders and extension staff. Our findings suggest there are important differences between irrigation and dryland contexts. Landholders in irrigation districts face higher opportunity costs and are more likely to mistrust government intentions. Other constraints to adoption include lack of financial resources, restricted time to carry out works and a high turnover of extension staff. Landholders adopted recommended vegetation management practices because those practices matched their values and goals. The importance of regular contact with a positive and enthusiastic extension officer was also evident. These findings have important implications for conservation policies and programs. Extension should move beyond arousing interest and include substantial follow‐up contact to maintain landholder motivation and confidence, as well as provide recognition for past landholder efforts. Incentive programs should be designed to provide wider landholder support with different entry points allowing participants to adapt, learn and build confidence. Incentives should address the constraints experienced by landholders, particularly at times of peak workloads and during drought. Work targets set for field staff can be too high and result in program staff focusing on accomplishing on‐ground work, rather than developing irrigators’ longer‐term commitment to vegetation conservation. 相似文献