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91.
Golgins, long stringlike proteins, tether cisternae and transport vesicles at the Golgi apparatus. We examined the attachment of golgin GMAP-210 to lipid membranes. GMAP-210 connected highly curved liposomes to flatter ones. This asymmetric tethering relied on motifs that sensed membrane curvature both in the N terminus of GMAP-210 and in ArfGAP1, which controlled the interaction of the C terminus of GMAP-210 with the small guanine nucleotide-binding protein Arf1. Because membrane curvature constantly changes during vesicular trafficking, this mode of tethering suggests a way to maintain the Golgi architecture without compromising membrane flow.  相似文献   
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Landscape Ecology - Evidence for effects of habitat loss and fragmentation on the viability of temperate forest herb populations in agricultural landscapes is so far based on population genetic...  相似文献   
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Journal of Pest Science - Host detection and parasitism by egg parasitoids involve host chemical recognition, spatial overlapping, and the ability to overcome physical barriers. Within the context...  相似文献   
96.
The decline of N from 15N-labelled mature pea residues was followed in unplanted soil over 16.5 yr. Eight years after residue incorporation, 24% of the residue 15N input was still present in the soil and, after 16.5 yr, 16% of the residue 15N input remained. A double exponential model successfully described the decay of N from 15N-labelled pea residues. The total residual 15N declined with average decay constants of 1.45 yr−1 for the 30 d to 1 yr period and of 0.07 yr−1 for the 1-16 yr period. Sixteen years following incorporation of the residues, indicator plants growing in residues-amended soils were obtaining 1.7% of their N from residue N. This is, to our knowledge, the longest study on decay of N in soils from 15N-labelled crop residues. The current study thus provides a unique data set for our empirical understanding of N-dynamics in agricultural systems, which is a prerequisite to parameterize and validate N-simulation models.  相似文献   
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ABSTRACT: Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a mortal and highly contagious disease in common and koi carp. The skin is the major portal of entry of CyHV-3 in carp after immersion in water containing the virus. In the present study, we used in vivo bioluminescence imaging to investigate the effect of skin mucus removal and skin epidermis lesion on CyHV-3 entry. Physical treatments inducing removal of the mucus up to complete erosion of the epidermis were applied on a defined area of carp skin just before inoculation by immersion in infectious water. CyHV-3 entry in carp was drastically enhanced on the area of the skin where the mucus was removed with or without associated epidermal lesion. To investigate whether skin mucus inhibits CyHV-3 binding to epidermal cells, tail fins with an intact mucus layer or without mucus were inoculated ex vivo. While electron microscopy examination revealed numerous viral particles bound on the fins inoculated after mucus removal, no particle could be detected after infection of mucus-covered fins. Finally, anti-CyHV-3 neutralising activity of mucus extract was tested in vitro. Incubation of CyHV-3 with mucus extract reduced its infectivity in a dose dependent manner. The present study demonstrates that skin mucus removal and epidermal lesions enhance CyHV-3 entry in carp. It highlights the role of fish skin mucus as an innate immune protection against viral epidermal entry.  相似文献   
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In the context of new alternative crop development in Europe, flavonoids were investigated in saw-wort, Serratula tinctoria L., a perennial Asteraceae which was used as a yellow dye until the 19th century. The phytochemical study described in this report indicates that leaves rather than stems should be used, and harvested at the end of the plant growing cycle, when flavonoids are particularly concentrated. Microspectrofluorometry showed a specific distribution of the flavonoid aglycone, luteolin in stomatal cells whereas the corresponding glycoside (luteolin-7-O-glucoside) was observed in palisade parenchyma cells. The flavonoids luteolin-4′-O-glucoside and 3-methylquercetin were isolated for the first time in S. tinctoria leaves and identified by NMR spectroscopy. The role of these flavonoids is discussed in this paper. Using a rapid and simple method, i.e. flavonoid histolocalization associated with UV, it was demonstrated that saw-wort contains high concentrations of luteolin derivatives and could be considered for use again as a natural dye.  相似文献   
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OBJECTIVE: To report outcome after surgical and interventional radiographic treatment of hepatic arteriovenous fistulae (HAVF) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=20) with HAVF. METHODS: Medical records of dogs with HAVF were reviewed. Referring veterinarians and owners were contacted by telephone. History, clinical signs, biochemical and hematologic variables, ultrasonographic and angiographic findings, surgical findings, techniques used to correct the HAVF, survival time, and clinical follow-up were recorded. RESULTS: Canine HAVF often appeared to be an arteriovenous malformation rather than a single fistula. Multiple extrahepatic portosystemic shunts were identified in 19 dogs. Surgery (lobectomy or ligation of the nutrient artery) and/or interventional radiology (glue embolization of the abnormal arterial vessels) was performed in 17 dogs. Thirteen dogs were treated by surgery alone, 4 dogs by glue embolization alone, and 1 dog by glue embolization and surgery. Three dogs treated by surgery alone died <1 month later, and 3 dogs were subsequently euthanatized or died because of persistent clinical signs. None of the dogs treated by glue embolization died <1month after the procedure and all were alive, without clinical signs, at follow-up (9-17 months). Overall, 9 of 12 (75%) dogs with long-term follow-up required dietary or medical management of clinical signs. CONCLUSION: HAVF-related death occurred less frequently after glue embolization than after surgery. CLINICAL RELEVANCE: Glue embolization may be a good alternative to surgery for treatment of certain canine HAVF.  相似文献   
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