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101.
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Book reviews     
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103.
The literature describing the use of sewage in various stages of treatment as well as sewage sludge, both settled and digested, as irrigation or fertilizer supplements is reviewed. A project is described in which anaerobically digested sewage sludge was added to a field in northwestern Pennsylvania, and aerobically digested sewage sludge was added to a field in southeastern Pennsylvania. Samples of soil were taken immediately before this addition, and immediately afterward. Samples were taken at weekly intervals for five months and all were tested for the presence of fungi. From these samples 95 species or species groups of fungi were reported of which several represent species known to produce plant disease. The extent to which populations of such fungi could build up in soils to which sewages or sludges are added frequently is unknown.
Zusammenfassung Die Literatur, die den Gebrauch des Kloakenwassers in verschiedenen Etappen der Behandlung so wie auch diejenigen, welche die Benützung des bearbeiteten und des verdauten Sediments, als ein Supplement der Irrigation oder der Düngung beschreiben, ist kritisch nachgeprüft worden. Ein Projekt ist beschrieben, in welchem ein anaerob verdautes Kloakenwasser-Sediment an einem Feld in Norwest-Pennsylvania und ein aerob verdautes Kloakenwasser-Sediment an einem anderen in Südost-Pennsylvania verwendet wurde. Proben vom Erdboden wurden unmittelbar vor und nach der Verwendung des Materials entnommen. Dieser Prozess ist wöchentlich für fünf Monate wiederholt und für die Gegenwart von Pilzen untersucht. Von diesen Proben sind 95 Arten oder Artgruppen von Pilzen berichtet, von denen mehrere bekannt sind, daß sie Pflanzenkrankheiten verursachen. Der Umfang, zu welchem Grade solche Pilze eine Verbreitung im Erdboden finden können, zu welchem Kloakenwasser oder dessen Sediment hinzugefügt war, ist häufig unbekannt.
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Moths are abundant and ubiquitous in vegetated terrestrial environments and are pollinators, important herbivores of wild plants, and food for birds, bats and rodents. In recent years, many once abundant and widespread species have shown sharp declines that have been cited by some as indicative of a widespread insect biodiversity crisis. Likely causes of these declines include agricultural intensification, light pollution, climate change, and urbanization; however, the real underlying cause(s) is still open to conjecture. We used data collected from the citizen science Garden Moth Scheme (GMS) to explore the spatial association between the abundance of 195 widespread British species of moth, and garden habitat and landscape features, to see if spatial habitat and landscape associations varied for species of differing conservation status. We found that associations with habitat and landscape composition were species-specific, but that there were consistent trends in species richness and total moth abundance. Gardens with more diverse and extensive microhabitats were associated with higher species richness and moth abundance; gardens near to the coast were associated with higher richness and moth abundance; and gardens in more urbanized locations were associated with lower species richness and moth abundance. The same trends were also found for species classified as increasing, declining and vulnerable under IUCN (World Conservation Union) criteria. However, vulnerable species were more strongly negatively affected by urbanization than increasing species. Two hypotheses are proposed to explain this observation: (1) that the underlying factors causing declines in vulnerable species (e.g., possibilities include fragmentation, habitat deterioration, agrochemical pollution) across Britain are the same in urban areas, but that these deleterious effects are more intense in urban areas; and/or (2) that urban areas can act as ecological traps for some vulnerable species of moth, the light drawing them in from the surrounding landscape into sub-optimal urban habitats.  相似文献   
106.
Coral Reefs - Palaeozoic coral communities were dominated by two extinct coral groups: Tabulata and Rugosa. Whilst they are not closely related to modern Scleractinia, they are morphologically...  相似文献   
107.
Antioxidants play key roles in preventing free radical damage to various molecules, cells, and tissues, but it is not well understood how variation in antioxidant levels may relate to the reproductive success or health of wild animals. We explored the relationship between circulating antioxidant concentrations and both body condition and timing of reproduction in male and female Florida Scrub-Jays (Aphelocoma coerulescens), a cooperatively breeding passerine bird. We examined whether levels of uric acid, vitamin E, and carotenoids (all potentially important antioxidants) were linked to body condition and timing of reproduction, two measures that are directly related to reproductive success. Antioxidant concentrations were not correlated with body condition, but they were related to timing of first clutch initiation, though not always in the predicted direction. Elevated circulating levels of carotenoids were associated with delayed clutch initiation in female breeders. Relatively higher vitamin E levels in control birds were associated with earlier clutch initiation, whereas male breeders that received long-term food supplementation had elevated levels of vitamin E and delayed reproduction. Several potential explanations for the link between elevated levels of antioxidants and delayed clutch initiation are discussed. Separate explanations for each sex include, but are not limited to, oxidative stress as a result of territory defense efforts in males, different dietary regimes due to supplementation, and mobilized plasma antioxidants in females that were coping with a stressor.  相似文献   
108.
Adenovirus (Ad) mutants that lack early region 4 (E4) are unable to produce the early regulatory proteins that normally inactivate the Mre11/Rad50/Nbs1 (MRN) sensor complex, which is a critical component for the ability of cells to respond to DNA damage. E4 mutant infection therefore activates a DNA damage response, which in turn interferes with a productive viral infection. MRN complex proteins localize to viral DNA replication centers in E4 mutant-infected cells, and this complex is critical for activating the kinases ataxia-telangiectasia mutated (ATM) and ATM and Rad3-related (ATR), which phosphorylate numerous substrates important for DNA repair, cell cycle checkpoint activation, and apoptosis. E4 mutant growth defects are substantially rescued in cells lacking an intact MRN complex. We have assessed the role of the downstream ATM and ATR kinases in several MRN-dependent E4 mutant phenotypes. We did not identify a role for either ATM or ATR in “repair” of E4 mutant genomes to form concatemers. ATR was also not observed to contribute to E4 mutant defects in late protein production. In contrast, the kinase activity of ATM was important for preventing efficient E4 mutant DNA replication and late gene expression. Our results suggest that the MRN complex interferes with E4 mutant DNA replication at least in part through its ability to activate ATM.  相似文献   
109.
Coral Reefs - This erratum is published as vendor overlooked corrections with misspelt scientific wording of family Siderastreidae.  相似文献   
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