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961.
Background: Data from short‐term experiments suggest that drinking water may promote weight loss by lowering total energy intake and/or altering metabolism. The long‐term effects of drinking water on change in body weight and composition are unknown, however. Objective: This study tested for associations between absolute and relative increases in drinking water and weight loss over 12 months. Methods and Procedures: Secondary analyses were conducted on data from the Stanford A TO Z weight loss intervention on 173 premenopausal overweight women (aged 25–50 years) who reported <1 l/day drinking water at baseline. Diet, physical activity, body weight, percent body fat (dual‐energy X‐ray absorptiometry), and waist circumference were assessed at baseline, 2, 6, and 12 months. At each time point, mean daily intakes of drinking water, noncaloric, unsweetened caloric (e.g., 100% fruit juice, milk) and sweetened caloric beverages, and food energy and nutrients were estimated using three unannounced 24‐h diet recalls. Beverage intake was expressed in absolute (g) and relative terms (% of beverages). Mixed models were used to test for effects of absolute and relative increases in drinking water on changes in weight and body composition, controlling for baseline status, diet group, and changes in other beverage intake, the amount and composition of foods consumed and physical activity. Results: Absolute and relative increases in drinking water were associated with significant loss of body weight and fat over time, independent of covariates. Discussion: The results suggest that drinking water may promote weight loss in overweight dieting women. 相似文献
962.
963.
Vadon-Le Goff S Kronenberg D Bourhis JM Bijakowski C Raynal N Ruggiero F Farndale RW Stöcker W Hulmes DJ Moali C 《The Journal of biological chemistry》2011,286(45):38932-38938
Bone morphogenetic protein-1 (BMP-1) and the tolloid-like metalloproteinases control several aspects of embryonic development and tissue repair. Unlike other proteinases whose activities are regulated mainly by endogenous inhibitors, regulation of BMP-1/tolloid-like proteinases relies mostly on proteins that stimulate activity. Among these, procollagen C-proteinase enhancers (PCPEs) markedly increase BMP-1/tolloid-like proteinase activity on fibrillar procollagens, in a substrate-specific manner. Here, we performed a detailed quantitative study of the binding of PCPE-1 and of its minimal active fragment (CUB1-CUB2) to three regions of the procollagen III molecule: the triple helix, the C-telopeptide, and the C-propeptide. Contrary to results described elsewhere, we found the PCPE-1-binding sites to be located exclusively in the C-propeptide region. In addition, binding and enhancing activities were found to be independent of the glycosylation state of the C-propeptide. These data exclude previously proposed mechanisms for the action of PCPEs and also suggest new mechanisms to explain how these proteins can stimulate BMP-1/tolloid-like proteinases by up to 20-fold. 相似文献
964.
965.
Condò I Ventura N Malisan F Tomassini B Testi R 《The Journal of biological chemistry》2006,281(24):16750-16756
Frataxin is a mitochondrial protein involved in iron metabolism. Defective expression of frataxin causes Friedreich ataxia (FA), an inherited degenerative syndrome characterized by ataxia, cardiomyopathy, and high incidence of diabetes. Here we report that frataxin-deficient cells are more prone to undergo stress-induced mitochondrial damage and apoptosis, while the overexpression of frataxin confers protection to a variety of cell types. Moreover, we reveal the existence of an extramitochondrial pool of frataxin, which can efficiently prevent mitochondrial damage and apoptosis in different cellular systems. Remarkably, extramitochondrial frataxin can fully replace mitochondrial frataxin in promoting survival of FA cells. 相似文献
966.
Migot-Nabias F Pelleau S Watier L Guitard J Toly C De Araujo C Ngom MI Chevillard C Gaye O Garcia A 《Microbes and infection / Institut Pasteur》2006,8(9-10):2352-2358
Numerous studies have shown that several red blood cell polymorphisms protect against severe malaria. Such a relation is much less clear for mild malaria attacks and for the asymptomatic carriage of Plasmodium falciparum. The impact of red blood cell polymorphisms on the level of parasite density was assessed in a group of 464 Senegalese children from the Sereer ethnic group, studied for 18 months. These genetic factors were also related to the malarial morbidity, investigated during 2 successive transmission seasons among 169 of these children. The frequencies of the host genetic factors in the whole group were 0.52 for blood group O, 0.13 for hemoglobin S, 0.16 for the G6PD A-deficient variant and 0.24 for alpha+-thalassemia (-alpha(3.7) deletion). Hemoglobin S was associated with protection against mild malaria attacks. None of the genetic factors was implicated in a better control of parasite densities. These associations may be particular to this ethnic group due to the specificities of malaria endemicity in this area. The pressure exerted in the area by other non-malarial infectious diseases as well as the genetic heterogeneity of circulating parasites may also contribute to these observations. 相似文献
967.
Cervi L MacDonald AS Kane C Dzierszinski F Pearce EJ 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(4):2016-2020
To examine the ability of dendritic cells (DC) to discriminate between helminth and microbial Ag and induce appropriately polarized Th responses, mouse DC were copulsed with the helminth Ag, schistosome egg Ag (SEA), along with the bacterium Proprionebacterium acnes, Pa, and transferred into wild-type mice. Strikingly, SEA/Pa-copulsed DC induced concurrent Pa-specific Th1 (but not Th2) responses and SEA-specific Th2 (but not Th1) responses. Although DC exposed to both Ag undergo many of the maturation-associated changes that accompany exposure to Pa alone, Pa-induced IL-12 production was inhibited by SEA. Examination of Ag uptake revealed that SEA and Pa are acquired via discrete pathways and enter nonoverlapping intracellular compartments. Data suggest that segregation of SEA and Pa into distinct compartments, coupled with SEA-induced modifications of the DC maturation pathway, are significant components of the ability of DC to interpret signals inherent to SEA and Pa and induce appropriately polarized Th responses. 相似文献
968.
Sandra Merscher Soumeya Bekri Bertie de Leeuw Florence Pedeutour Josiane Grosgeorge Thomas B. Shows Roman Müllenbach Denis Le Paslier Norma J. Nowak Patrick Gaudray 《Genomics》1997,39(3):340
The distal part of 11q13, which contains several genes relevant to human diseases, has been poorly mapped as part of genome-wide mapping efforts. In the prospect of drawing a fine-scale integrated map of the area containingKRN1andOMP,we have established a framework of markers by hybridization to DNA of somatic cell hybrids and by fluorescencein situhybridization (FISH) on metaphase chromosomes. The probes studied were used to isolate 27 YACs and 16 cosmids that could be organized in three contigs covering approximately 6 Mb. These contigs were separated by two gaps that are likely to contain sequences underrepresented in YAC libraries. They were then integrated based on long-range restriction mapping and DNA-fiber FISH into a high-resolution physical map, which covers a 5.5-Mb region and includes 36 anonymous markers and 10 genes. This map will be used to search for genes within the 2/3 of this region where none have been localized as yet. It will also lay the ground for the characterization of an amplicon surroundingGARPin breast cancer and for the search of disease genes within this region. 相似文献
969.
Latifa Zhouri Rajae Kallida Naima Shaimi Philippe Barre Florence Volaire Fatima Gaboun Malika Fakiri 《Saudi Journal of Biological Sciences》2019,26(1)
Climate change models predict frequent and intense droughts in the world. Development of drought-tolerant species and cultivars is necessary to cope with such changes. Forage grass species are affected, especially in the Mediterranean region. The aim of the present study was to investigate the diversity for drought survival, summer dormancy, and productivity within a cocksfoot population.The study was conducted in Morocco, under field conditions from 2011 to 2013. 283 genotypes of cocksfoot and parents were tested, characterized for dry matter yield, heading date, plant height, senescence, summer dormancy, and drought survival. Results exhibited a large variability between traits. 79% of the population had survived after severe drought summer while 57% yielded more than both parents. Also, 63% of the progeny had an intermediate score of summer dormancy estimated by senescence score. Large variability was also noticed for heading date and plant height. Several accessions combined a high yield and persistence under severe summer drought. Which explain the significant correlation (r = 0.18, P < 0.005) founded between total dry matter accumulated in 2013 and plant survival. Accordingly, our results showed that we can rise persistent and resilient genotypes among population with a good level of biomass. 相似文献
970.
David Wilson Catherine A. Farrell David Fallon Gerald Moser Christoph Müller Florence Renou‐Wilson 《Global Change Biology》2016,22(12):4080-4095
Drained peat soils are a significant source of greenhouse gas (GHG) emissions to the atmosphere. Rewetting these soils is considered an important climate change mitigation tool to reduce emissions and create suitable conditions for carbon sequestration. Long‐term monitoring is essential to capture interannual variations in GHG emissions and associated environmental variables and to reduce the uncertainty linked with GHG emission factor calculations. In this study, we present GHG balances: carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) calculated for a 5‐year period at a rewetted industrial cutaway peatland in Ireland (rewetted 7 years prior to the start of the study); and compare the results with an adjacent drained area (2‐year data set), and with ten long‐term data sets from intact (i.e. undrained) peatlands in temperate and boreal regions. In the rewetted site, CO2 exchange (or net ecosystem exchange (NEE)) was strongly influenced by ecosystem respiration (Reco) rather than gross primary production (GPP). CH4 emissions were related to soil temperature and either water table level or plant biomass. N2O emissions were not detected in either drained or rewetted sites. Rewetting reduced CO2 emissions in unvegetated areas by approximately 50%. When upscaled to the ecosystem level, the emission factors (calculated as 5‐year mean of annual balances) for the rewetted site were (±SD) ?104 ± 80 g CO2‐C m?2 yr?1 (i.e. CO2 sink) and 9 ± 2 g CH4‐C m?2 yr?1 (i.e. CH4 source). Nearly a decade after rewetting, the GHG balance (100‐year global warming potential) had reduced noticeably (i.e. less warming) in comparison with the drained site but was still higher than comparative intact sites. Our results indicate that rewetted sites may be more sensitive to interannual changes in weather conditions than their more resilient intact counterparts and may switch from an annual CO2 sink to a source if triggered by slightly drier conditions. 相似文献