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111.
Body mass and diet are two fundamental ecological parameters that influence many other aspects of an animal's biology. Thus, the potential physiological and ecological processes linking size and diet have been the subject of extensive research, although the broad macroevolutionary relationship between the two traits remains largely unexplored phylogenetically. Using generalized Ornstein–Uhlenbeck models and data on over 1350 species of mammal, we reveal that evolutionary changes in body mass are consistently associated with dietary changes across mammals. Best‐fitting models find that herbivores are substantially heavier than other dietary groups and that omnivores are frequently intermediate in mass between herbivores and carnivores. Interestingly, although flying and swimming both place very different physical constraints on mass, bats still follow the general mammalian pattern but marine mammals do not. Such differences may be explained by reduced gravitational constraints on size in water along with ecological differences in food availability between aquatic and terrestrial realms, allowing marine carnivores to become the largest mammals on earth. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 115 , 173–184.  相似文献   
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希瓦氏菌(Shewanella spp.)是海产品中常见的优势腐败菌,易在食品加工设备表面形成生物被膜而难以清除。生物被膜的存在不仅会造成食品的持续污染和交叉污染,也会影响加工设备的使用,从而对国民健康和经济发展造成威胁。目前,针对希瓦氏菌生物被膜的研究主要集中在表型研究上,对其生物被膜形成分子机制的研究尚处于起步阶段。总结希瓦氏菌生物被膜的形成过程,重点论述希瓦氏菌生物被膜的形成机制并对希瓦氏菌生物被膜控制方法进行简要概括,展望未来的研究方向,以期为希瓦氏菌生物被膜的深入研究提供参考。  相似文献   
114.
We provide an extensive review on current knowledge and future research paths on the topic of resource allocation and compensation during development in holometabolous insects, emphasizing the role of resource management during development, and how compensatory mechanisms may be acting to remediate nutritional deficiencies carried over from earlier stages of development. We first review resource allocation in “open” and “closed” developmental stages and then move on to the topic of modelling resource allocation and its trade-offs. In doing so, we review novel methodological developments such as response-surface methods and mixture experiments as well as nutritional geometry. We also dwell on the fascinating topic of compensatory physiology and behavior. We finish by discussing future research paths, among them the emerging field of nutrigenomics and gut microbiome, which will shed light into the yet poorly understood role of the symbiotic microbiota in nutrient compensation or assimilation.  相似文献   
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In the present study, we investigated the application of 13 short tandem repeat (STR) loci (D13S317, D7S820, TH01, D16S539, CSFIPO, VWA, D8S1179, TPOX, FGA, D3S1358, D21S11, D18S51 and D5S818) routinely used in forensic analysis, for delineating population relationships among seven human populations representing the two major geographic groups, namely the southern and northern Chinese. The resulting single topology revealed pronounced geographic and population partitioning, consistent with the differences in geographic location, languages and eating habits. These findings suggest that forensic STR loci might be particularly powerful tools in providing the necessary fine resolution for reconstructing recent human evolutionary history.  相似文献   
117.
Abstract Is the cost of reproduction different between males and females? On the one hand, males typically compete intensely for mates, thus sexual selection theory predicts higher cost of reproduction for males in species with intense male‐male competition. On the other hand, care provisioning such as incubating the eggs and raising young may also be costly, thus parental care theory predicts higher mortality for the care‐giving sex, which is often the female. We tested both hypotheses of reproductive costs using phylogenetic comparative analyses of sex‐specific adult mortality rates of 194 bird species across 41 families. First, we show that evolutionary increases in male‐male competition were associated with male‐biased mortalities. This relationship is consistent between two measures of mating competition: social mating system and testis size. Second, as predicted by the parental cost hypothesis, females have significantly higher adult mortalities (mean ± SE, 0.364 ± 0.01) than males (0.328 ± 0.01). However, the mortality cost of parental care was only detectable in males, when the influence of mating competition was statistically controlled. Taken together, our results challenge the traditional explanation of female‐biased avian mortalities, because evolutionary changes in female care were unrelated to changes in mortality bias. The interspecific variation in avian mortality bias, as we show here, is driven by males, specifically via the costs of both mating competition and parental care. We also discuss alternative hypotheses for why most birds exhibit female‐biased mortalities, whereas in mammals male‐biased mortalities predominate.  相似文献   
118.
Dynamic interactions between intracellular networks regulate cellular homeostasis and responses to perturbations. Targeted therapy is aimed at perturbing oncogene addiction pathways in cancer, however, development of acquired resistance to these drugs is a significant clinical problem. A network‐based computational analysis of global gene expression data from matched sensitive and acquired drug‐resistant cells to lapatinib, an EGFR/ErbB2 inhibitor, revealed an increased expression of the glucose deprivation response network, including glucagon signaling, glucose uptake, gluconeogenesis and unfolded protein response in the resistant cells. Importantly, the glucose deprivation response markers correlated significantly with high clinical relapse rates in ErbB2‐positive breast cancer patients. Further, forcing drug‐sensitive cells into glucose deprivation rendered them more resistant to lapatinib. Using a chemical genomics bioinformatics mining of the CMAP database, we identified drugs that specifically target the glucose deprivation response networks to overcome the resistant phenotype and reduced survival of resistant cells. This study implicates the chronic activation of cellular compensatory networks in response to targeted therapy and suggests novel combinations targeting signaling and metabolic networks in tumors with acquired resistance.  相似文献   
119.
为了比较尿液蛋白PVDF膜富集保存法(尿膜)和尿液直接冻存法两种方法的优缺点。通过比较两种方法在时间、所占空间、费用、蛋白降解程度及大样本临床实践性方面的区别。发现在所占空间、电费方面及临床实践性方面尿膜保存法优于直接冻存法,而在时间及耗材花费方面直接冻存法优于尿膜保存法。因此尿蛋白的尿膜保存法比直接冻存法有更强的实际应用价值。  相似文献   
120.
中国三江源国家公园与韩国智异山国家公园的对比研究   总被引:1,自引:0,他引:1  
自1967年智异山被认定为韩国首个国家公园以来,韩国以国家公园为主体的自然保护地体系建设已历经50余年。这期间韩国在国家公园的建设中积累了大量经验,十分值得我国借鉴。选取我国首个国家公园体制试点——三江源国家公园和韩国首个国家公园——智异山国家公园为研究对象,对二者的管理现状进行了定性分析,并运用基于最优实践的国家公园管理能力评价方法对二者的管理能力进行了定量评价。研究表明:三江源国家公园的管理能力综合得分低于智异山国家公园,在体制建设、保障机制、资源环境管理、社区管理和科普教育五个方面均与智异山国家公园存在一定差距;智异山国家公园在资源本底调查、法制建设、多方参与、环境教育和游憩管理方面的管理能力十分突出,为三江源国家公园管理能力的提升提供了有益借鉴;三江源国家公园在生态补偿和制度约束方面具有比较优势,但在自然资源权属、资源本底调查、社区组织建设和游憩管理方面则亟待提升。在此基础上,针对三江源国家公园建设提出了强化科研支撑、健全多方参与制度、推进全民福利共享三项建议,针对我国国家公园体制建设提出了制定《国家公园法》、设置自然保护地顶层规划两项建议,以期促进三江源国家公园管理能力提升、推动我国国家公园体制建设。  相似文献   
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