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941.
The objective of this study was to estimate the potential short‐term economic loss as a result of replacing the commercial diamond codend with a square mesh codend, and to compare fish lengths captured in 40 mm square (S40) vs 44 mm commercial hand‐woven diamond (CD44) mesh codends for red mullet (Mullus barbatus), common pandora (Pagellus erythrinus), bogue (Boops boops), European hake (Merluccius merluccius), axillary seabream (Pagellus acarne), and brushtooth lizardfish (Saurida undosquamis). A total of 20 hauls (10 hauls for S40 and 10 hauls for CD44) were conducted onboard a commercial trawler between 27 February and 11 April 2012 in Mersin Bay in the northeastern Mediterranean. Results showed that the 40 mm square mesh codend caught significantly fewer juveniles of all aforementioned species. However, when changing from the commercial diamond codend to the 40 mm square mesh codend the potential economic loss of revenue was found to be 40% in the study period, which covered the final 6 weeks of the fishing season.  相似文献   
942.
The cell surface is the cellular compartment responsible for communication with the environment. The interior of mammalian cells undergoes dramatic reorganization when cells enter mitosis. These changes are triggered by activation of the CDK1 kinase and have been studied extensively. In contrast, very little is known of the cell surface changes during cell division. We undertook a quantitative proteomic comparison of cell surface‐exposed proteins in human cancer cells that were tightly synchronized in mitosis or interphase. Six hundred and twenty‐eight surface and surface‐associated proteins in HeLa cells were identified; of these, 27 were significantly enriched at the cell surface in mitosis and 37 in interphase. Using imaging techniques, we confirmed the mitosis‐selective cell surface localization of protocadherin PCDH7, a member of a family with anti‐adhesive roles in embryos. We show that PCDH7 is required for development of full mitotic rounding pressure at the onset of mitosis. Our analysis provided basic information on how cell cycle progression affects the cell surface. It also provides potential pharmacodynamic biomarkers for anti‐mitotic cancer chemotherapy.  相似文献   
943.
944.
Marine traffic is a significant source of disturbance to the bottlenose dolphin population in the Istanbul Strait, Turkey. To determine the importance of this threat, behavioral data together with sighting data of both dolphins and marine vessels were assessed for 2012. The current study suggests that the Istanbul Strait is used mostly as a foraging ground for bottlenose dolphins. Nonetheless, in the same area there is intense marine traffic as well as increase of industrial fishing activities in autumn. The findings of this study indicated that high‐speed ferries and high‐speed boats were the most significant source of disturbance. Moreover, increased densities of fishing vessels resulted in a drastic decline of dolphin sightings. This study highlights that vessel type, speed, distance, and density have a cumulative negative effect on dolphins. In order to mitigate the impacts of vessels, it is necessary to establish managed areas in the Istanbul Strait. Such proposed areas should limit speed and density of marine traffic and have specific restrictions on vessel routes. We propose three different seasonal managed areas according to their values as critical habitat for bottlenose dolphins in the strait.  相似文献   
945.
Isolates of Rhizoctonia spp. associated with stem canker and black scurf disease of potato were examined for their anastomosis group, sequence variations in the ITS‐5.8S rDNA region, pathogenicity and sensitivity to fungicides. A total of 92 isolates were obtained from diseased tuber, stolon and sprouts of the potato plants, collected from five districts of Bolu province, Turkey. Based on the anastomosis group and the similarity of the nucleotide sequence of the ITS‐5.8S rDNA, most of the isolates (81.5%) were identified as AG 3 PT. Other isolates belonged to AG 2‐1 (1.08%), AG 2‐2 IV (1.08%), AG 4 HG II (8.07%), AG 5 (2.17%), binucleate Rhizoctonia AG A (1.08%) and AG K (4.35%). Pathogenicity tests showed that isolates of AG 3 PT, AG 4 HG II and AG 5 caused similar degrees of disease severity on 45‐day‐old potato seedlings, whereas AG 2‐1 was moderately virulent. AG 2‐2 IV and binucleate Rhizoctonia spp. were weakly pathogenic or non‐pathogenic on potato seedlings. In this study, anastomosis groups of Rhizoctonia spp. isolates associated with potato in Turkey were characterized for the first time using molecular techniques and classified at the level of subgroups. Furthermore, the effect of selected fungicides was evaluated on disease development caused by soil‐borne inoculums of different anastomosis groups (AGs). Flutolanil and Bacillus subtilis QST 713 were found to be most effective against the Rhizoctonia isolates tested. These results revealed significant differences among the fungicides on disease development resulted from the different AGs.  相似文献   
946.
Adverse weather conditions during parental care may have direct consequences for offspring production, but longer‐term effects on juvenile and parental survival are less well known. We used long‐term data on reproductive output, recruitment, and parental survival in northern wheatears (Oenanthe oenanthe) to investigate the effects of rainfall during parental care on fledging success, recruitment success (juvenile survival), and parental survival, and how these effects related to nestling age, breeding time, habitat quality, and parental nest visitation rates. While accounting for effects of temperature, fledging success was negatively related to rainfall (days > 10 mm) in the second half of the nestling period, with the magnitude of this effect being greater for breeding attempts early in the season. Recruitment success was, however, more sensitive to the number of rain days in the first half of the nestling period. Rainfall effects on parental survival differed between the sexes; males were more sensitive to rain during the nestling period than females. We demonstrate a probable mechanism driving the rainfall effects on reproductive output: Parental nest visitation rates decline with increasing amounts of daily rainfall, with this effect becoming stronger after consecutive rain days. Our study shows that rain during the nestling stage not only relates to fledging success but also has longer‐term effects on recruitment and subsequent parental survival. Thus, if we want to understand or predict population responses to future climate change, we need to consider the potential impacts of changing rainfall patterns in addition to temperature, and how these will affect target species' vital rates.  相似文献   
947.
948.
949.
Morphological and micromorphological characters of the nutlets of ten Onosma species in Turkey were reported. Studied fruit surfaces show some variations. Based on the structure and patterns of epidermis cells of the nutlets, two principal types can be distinguished. In Type 1, the epidermal cells of the nutlet surface are formed in a reticulate pattern with varied sizes and shapes of the meshes. This type is the most common type in the studied species. Seven of the species observed belong to the reticulate type, i.e. O. bracteosum, O. mutabile, O. aleppicum, O. bornmuelleri, O. aucheranum, O. araraticum and O. tauricum. In Type 2, the epidermal cells of the nutlet surface are formed in an elongated type with varied sizes and shapes. Three of the observed species belong to this type, i.e. O. roussaei, O. isauricum and O. stenolobum. Significant taxonomic differences between species were determined on the surface of the nutlets.  相似文献   
950.
Culturally modified trees (CMTs) provide unique insights into traditional knowledge and uses of the forest ecosystems. In close relation to pre-industrial livestock herding in central Sweden, it was a custom to carve text and symbols on trees and use them as notice boards in the forest. The main aim of this study was to document and analyse remaining carved trees in a managed forest landscape of 160 km2. The same area was surveyed twice, once in 1986 and once in 2003. 488 carved trees were documented and classified into legible themes that were interpreted in the light of past herding practices. Name was the most common theme, found in 85% of the carvings. Most of the carvings were made in the period from the 1750s until the early 1900s. The custom of carving on trees was closely related to important grazing areas and the need to establish rights to them. The main losses of carved trees nowadays are due to their natural death and decay as most of the carved trees are located in areas that are not targeted for management. A primary recommendation for preservation is therefore to continue documentation of the trees because of the noticeable deterioration in readability of the carvings.  相似文献   
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