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131.
Twenty two species of the paper wasp genus Ropalidia Guérin-Méneville, 1831, are listed from China. Among them, R. malaisei van der Vecht, 1962, R. cyathiformis (Fabricius, 1804), R. santoshae Das & Gupta, 1989, R. scitula (Bingham, 1897), R. obscura Gusenleitner, 1996 and R. ornaticeps (Cameron, 1900) are new records from China. A new species, R. parartifex Tan & van Achterberg, is described. Their diagnostic characteristics are summarized in an illustrated key and 36 colourplates.  相似文献   
132.
Since the proposition in 1975 of the European Neogene Mammal (MN) scale by Pierre Mein, the amount of taxonomical, stratigraphical and chronological information around Europe has increased exponentially. In this paper, the stratigraphical schemes of three of the best studied areas for the Lower and Middle Miocene, the Aragonian type area in Spain and the Upper Freshwater Molasse from the North Alpine Foreland Basin in Switzerland and Bavaria, are compared. The correlation of their local biostratigraphies are discussed. Sixteen rodent's events are studied and ranked in the three areas according to their local biostratigraphy. This study shows, and quantifies for the first time, the significant asynchronies of the different included rodent events. The MN-system is discussed in the light of those results. In accordance, we propose that it is still useful but only in a biochronological way, as a sequence of time-ordered reference localities allowing coarse long-distance correlations. In order to obtain better temporal resolution, this system has to be combined with local biostratigraphies that are well calibrated to the time scale, implementing the information about synchrony and diachrony of mammal events in different areas.  相似文献   
133.
Pure (single) cultures of microorganisms and mixed microbial communities (microbiomes) have been important for centuries in providing renewable energy, clean water and food products to human society and will continue to play a crucial role to pursue the Sustainable Development Goals. To use microorganisms effectively, microbial engineered processes require adequate control. Microbial communities are shaped by manageable deterministic processes, but also by stochastic processes, which can promote unforeseeable variations and adaptations. Here, we highlight the impact of stochasticity in single culture and microbiome engineering. First, we discuss the concepts and mechanisms of stochasticity in relation to microbial ecology of single cultures and microbiomes. Second, we discuss the consequences of stochasticity in relation to process performance and human health, which are reflected in key disadvantages and important opportunities. Third, we propose a suitable decision tool to deal with stochasticity in which monitoring of stochasticity and setting the boundaries of stochasticity by regulators are central aspects. Stochasticity may give rise to some risks, such as the presence of pathogens in microbiomes. We argue here that by taking the necessary precautions and through clever monitoring and interpretation, these risks can be mitigated.  相似文献   
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135.
A growing group of migrants age in an environment in which the dominant language (L2) differs from their mother tongue (L1). This study considers the occurrence of a language barrier in accessing (information on) health and healthcare provisions, and under which circumstances a limited proficiency in the L2 negatively influences well-being for a group of older Turkish women in the Netherlands. Data from interviews with 39 Turkish females reveal that a limited L2 proficiency does not automatically result in a lower level of well-being. When individuals are well-embedded in a social network (and feel belonging to it), a limited L2 proficiency can be alleviated by either L1 assistance from their environment or by facilitating an interpreter in L2 situations. However, when such a network is absent, L2 situations can cause anxiety, which may have repercussions for well-being. Even though there is no clear one-on-one relationship between language and well-being, language does play a role in many (social) processes that influence well-being.  相似文献   
136.
Understanding the causes and consequences of population phenotypic divergence is a central goal in ecology and evolution. Phenotypic divergence among populations can result from genetic divergence, phenotypic plasticity or a combination of the two. However, few studies have deciphered these mechanisms for populations geographically close and connected by gene flow, especially in the case of personality traits. In this study, we used a common garden experiment to explore the genetic basis of the phenotypic divergence observed between two blue tit (Cyanistes caeruleus) populations inhabiting contrasting habitats separated by 25 km, for two personality traits (exploration speed and handling aggression), one physiological trait (heart rate during restraint) and two morphological traits (tarsus length and body mass). Blue tit nestlings were removed from their population and raised in a common garden for up to 5 years. We then compared adult phenotypes between the two populations, as well as trait‐specific Qst and Fst. Our results revealed differences between populations similar to those found in the wild, suggesting a genetic divergence for all traits. QstFst comparisons revealed that the trait divergences likely result from dissimilar selection patterns rather than from genetic drift. Our study is one of the first to report a QstFst comparison for personality traits and adds to the growing body of evidence that population genetic divergence is possible at a small scale for a variety of traits including behavioural traits.  相似文献   
137.
The abundance of the human intestinal symbiont Akkermansia muciniphila has found to be inversely correlated with several diseases, including metabolic syndrome and obesity. A. muciniphila is known to use mucin as sole carbon and nitrogen source. To study the physiology and the potential for therapeutic applications of this bacterium, we designed a defined minimal medium. The composition of the medium was based on the genome‐scale metabolic model of A. muciniphila and the composition of mucin. Our results indicate that A. muciniphila does not code for GlmS, the enzyme that mediates the conversion of fructose‐6‐phosphate (Fru6P) to glucosamine‐6‐phosphate (GlcN6P), which is essential in peptidoglycan formation. The only annotated enzyme that could mediate this conversion is Amuc‐NagB on locus Amuc_1822. We found that Amuc‐NagB was unable to form GlcN6P from Fru6P at physiological conditions, while it efficiently catalyzed the reverse reaction. To overcome this inability, N‐acetylglucosamine needs to be present in the medium for A. muciniphila growth. With these findings, the genome‐scale metabolic model was updated and used to accurately predict growth of A. muciniphila on synthetic media. The finding that A. muciniphila has a necessity for GlcNAc, which is present in mucin further prompts the adaptation to its mucosal niche.  相似文献   
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139.
A comparative study was performed of interphase in situ hybridization (ISH) to deparaffinized 4-m tissue sections and nuclear suspensions from eight prostatic adenocarcinomas, as well as one normal prostatic control. Whole nuclear suspensions were derived from the same tumor areas to evaluate differences of ISH to truncated versus whole nuclei. DNA probes specific for the centromeres of chromosome 1, 7, 8, 10, and Y were used for detection of numerical chromosomal changes and aneuploidy. In six adenocarcinomas chromosome aberrations (+7, +8, –8, –10, –Y) were seen. However, ISH to sections revealed focal aberrations (–10, –Y) in four cases that could not be distinguished in the suspensions. Chromosomal alterations occurring in larger tumor areas were also detected in the nuclear suspensions. Chromosome copy number changes, especially gains, were better discriminated in the nuclear suspensions. The rate of ISH aneuploidy seen in nuclear suspensions corresponded with that observed in the tissue sections (P<0.01). Ploidy patterns as assessed by ISH to sections and nuclear suspensions were in concordance with DNA flow cytometry (bothP<0.001). We conclude that both section and suspension ISH were able to accurately detect aneuploidy and numerical chromosomal aberrations occurring in larger histological areas. However, section ISH was also capable of revealing (small) focal cytogenetic abnormalities, due to a precise analysis of only target cells. Focal abnormalities were not detected by suspension ISH, probably due to an admixture of non-aberrant tumor cells and stromal elements.  相似文献   
140.
A microecosystem consisting of three subsystems roughly representing the trophic levels of autotrophs, herbivores and decomposers was developed. A recirculating flow of water connected the three subsystems. Analysis of the data over a period of 7500 days indicates that the system has remained in the same state and has the prospect of being immortal. The Daphnia population showed periods of large oscillations, but also long periods of almost constant numbers. External factors were responsible for the initiation of the oscillations. The threshold food level for population increase was lower than mostly is found for individual growth, indicating adaptation to low food concentrations.  相似文献   
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