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61.
In South Asia, and throughout the developing world, the predominant official approach to livestock development has been improvement of production by means of upgrading local breeds via cross-breeding with exotic animals. This strategy has led to the replacement and dilution of locally adapted breeds with non-native ones. This has resulted in an alarming loss that has been estimated by the Food and Agriculture Organization of the United Nations to amount to one breed every two weeks. Based on selected case studies this paper argues that development strategies using locally adapted breeds and species are much more likely to benefit livestock keepers whilst also maintaining domestic animal diversity and bearing a smaller ecological footprint. It also analyses the rationale for “Livestock Keepers’ Rights”, a principle that grew out of the struggle of traditional livestock keepers to retain control over their production resources, such as grazing areas and breeding stock, in the face of unfavourable policy environments.  相似文献   
62.
Using a geographic information system (GIS), by analysis of the relationship between the spatial distribution of cattle density and the risk factors temperature, altitude and rainfall, we defined geographical habitats enabling optimal development and competence of Culicoides spp. to transmit Bluetongue-Virus (BTV): Risk zones (low, high, highest risk) were identified mainly in Baden-Württemberg, Hessen and Rheinland-Pfalz if persistently infected ruminants are imported into these zones in summer (June to August mainly), based on the current climatic conditions, BTD outbreaks are considered a real possibility. Overwintering of the virus seems unlikely. However, global warming will lead to a steady increase of the size of the risk zones. In addition, the possibility of primary outbreaks increases. The reason for this is not only the expected northern shift of Culicoides imicola, but in addition an increasing vector competence of domestic Culicoides species. We therefore recommend the storage of vaccines as well as conducting ecological studies analysing the presence of Culicoides vectors. Using the data from these studies, it will be possible to produce updated quantitative risk assessment via GIS.  相似文献   
63.
The fetal stress responses in sows euthanized by electrical current during their second and last trimester of pregnancy (G1 and G2) were evaluated. Three methods of euthanasia of pregnant sows generally applicable to cases of epizootic or emergency slaughter were investigated: 1. conventional application of electrical current to the head and heart (HH); 2. application of electrical current to the head, heart and the uterus (HHU); 3. application of electrical current to the head, heart and from the upper body to the vagina (HHV). Fetuses were delivered by cesarean section at intervals of 3 to 4 minutes and remained attached to the sow by the umbilical cord. Fetal vitality, reflexes, heart rate, blood pressure, rectal body temperature, intracardial arteriovenous pCO2, pH and lactic acid were monitored for a period of 30 minutes. No method was found to kill the fetal pigs immediately. In fetuses at G1 there were no significant differences between the HH and HHU and HHV methods. Fetuses at G2 showed a significantly faster decrease in heart rate and blood pressure as well as a shorter period of time for the absence of fetal body movements and reflexes for the HHT method, compared to the other methods. Since it is not yet known to what extent the fetal pig experiences pain and suffering, the prolonged process of dying for the in utero fetus due to hypoxia which includes struggling and gasps is inconsistent with criteria for humane euthanasia and animal welfare.  相似文献   
64.
The present paper presents the SAFIR project (www.safir4eu.org), which addresses two fundamental problems that over the past decade increasingly have become concerns of the general public: the one problem being the jeopardizing of safety and quality of our food products, while the other being the increasing competition for clean freshwater. The SAFIR project has a multi-disciplinary approach, which integrates the European as well as the global dimension of the EU-policy on food quality and safety. The main driving force behind the project idea is new research results that demonstrated that scheduled uneven irrigation patterns can increase the water use efficiency as well as the quality of vegetable crops. Furthermore, recent innovations in the water treatment and irrigation industry have shown potential for the use of low quality water resources, such as reclaimed water or surface water in peri-urban agriculture, for irrigation of vegetable crops without threaten food safety and quality. The results of SAFIR were achieved from field experiments in Europe and China and modeling activities both at field and farm scale. The present article describes the structure of the project and highlights the main findings and recommendations of the project described in detail in already published papers and in accompanying papers in this special issue.  相似文献   
65.
In today's aquaculture of Atlantic salmon (Salmo salar L.), a majority of viral disease outbreaks occur after seawater transfer. A relevant question is how the parr–smolt transformation influences the efficacy of viral vaccines and the innate resistance against viral diseases. In this study, vaccinated and unvaccinated A. salmon parr were exposed to different photoperiodic regimens (1‐, 3‐ or 6‐week continuous light—WCL). Fish groups at different stages in the smoltification process were induced, as demonstrated by differences in morphological and physiological smolt parameters. At the time of seawater transfer, the 6‐WCL group had reached a more pronounced stage in the smoltification process than the 1‐WCL group. In unvaccinated fish, the subsequent cohabitation challenge with infectious pancreatic necrosis virus (IPNV) gave a significantly higher accumulated mortality in the 6‐WCL group (87%) compared to the 1‐WCL group (39%). In the vaccinated groups, this effect was not apparent and there were no differences in accumulated mortality between the 1 WCL, 3 WCL and 6‐WCL groups. These data suggest that the resistance to IPN in A. salmon was negatively influenced by smoltification, while vaccine‐mediated protection to IPN was maintained equally well irrespective of smolt status.  相似文献   
66.
67.
Seaweed lectins, especially high-mannose-specific lectins from red algae, have been identified as potential antiviral agents that are capable of blocking the replication of various enveloped viruses like influenza virus, herpes virus, and HIV-1 in vitro. Their antiviral activity depends on the recognition of glycoprotein receptors on the surface of sensitive host cells—in particular, hemagglutinin for influenza virus or gp120 for HIV-1, which in turn triggers fusion events, allowing the entry of the viral genome into the cells and its subsequent replication. The diversity of glycans present on the S-glycoproteins forming the spikes covering the SARS-CoV-2 envelope, essentially complex type N-glycans and high-mannose type N-glycans, suggests that high-mannose-specific seaweed lectins are particularly well adapted as glycan probes for coronaviruses. This review presents a detailed study of the carbohydrate-binding specificity of high-mannose-specific seaweed lectins, demonstrating their potential to be used as specific glycan probes for coronaviruses, as well as the biomedical interest for both the detection and immobilization of SARS-CoV-2 to avoid shedding of the virus into the environment. The use of these seaweed lectins as replication blockers for SARS-CoV-2 is also discussed.  相似文献   
68.
This report aims to describe the first case of muscular and collagenous choristoma in a dog. A 10-yr-old female mixed-breed dog presented with lateral recumbence, vocalization, positional vertical nystagmus, divergent strabismus, anisocoria, and status epilepticus. The clinical condition evolved to stupor and ultimately, death. Necropsy revealed a white mass causing an irregular increase in the volume of the cerebellar vermis. In histological analysis, a well circumscribed, unencapsulated mass was observed in the cerebellum, consisting of fibers of striated skeletal muscle and collagen fibers, mostly mineralized. Based on the histopathological and histochemical findings, a diagnosis of muscular and collagenous cerebellar choristoma was made.  相似文献   
69.
The riparian forests along braided rivers are dynamic, frequently rejuvenated by floods and channel changes, and thus dominated by pioneer to middle stages of succession; they are sites of high biodiversity in some regions. The Lower Eygues River (drainage area 1150 km2 in southeastern France) is such a braided river system with large alluvial forests dominated by Salix alba, Populus alba, and P. nigra. It was identified as a site of ecological interest by the EU under the Natura 2000 program. Such forests elsewhere in Europe have been identified as reference ecosystems. We documented the historical evolution of this alluvial forest from detailed (1:2500 scale) early 19th C parcel maps, early 20th C topographic maps, aerial photography from 1947 to 1996, and field surveys of topography and riparian vegetation in 1997–1998. Our results show that in 1830, the channel was wide, aggraded, and agricultural pressure extended literally to the channel edge. With decline in the rural population and reduced agricultural and grazing pressure in the catchment, erosion rates declined. Reduced sediment supply led to channel narrowing and incision. This channel narrowing, coupled with reduced agricultural pressure along the banks, has allowed riparian forest to colonize former active channel areas, especially within late 19th-century 20th century flood dykes. In recent decades, aggregate mining, and clearing for recreation and agriculture have fragmented the forest. Thus, the alluvial forest of the Lower Eygues is largely an artifact of changing human land-use over the past century, a context that should frame efforts for preservation and restoration.  相似文献   
70.
The almost simultaneous initial detections of avian influenza A H5N1 viruses in central Europe in February 2006, at a time devoid of migratory bird activity, raised the question of the origin of these viruses. This report presents molecular data from Europe providing evidence for multiple and spatially overlapping H5N1 introductions into Bavaria, Germany.  相似文献   
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