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161.
A seven-year-old crossbred male dog with a suspected leukaemic condition was referred for investigation and treatment. A bone marrow aspirate revealed an acute myeloid leukaemia. Combination chemotherapy was administered and the dog initially improved, but 18 days after the initiation of therapy its body condition deteriorated and the animal developed acute respiratory distress. On postmortem examination, extensive leukaemic pulmonary infiltrates were evident.  相似文献   
162.
Catechol O-methyltransferase (COMT) inactivates catecholamines and catechol-containing drugs such as L-DOPA. The common genetic polymorphism Val158Met in the human COMT gene is suspected to be associated with "persistence" or risk for schizophrenia. In this study, we attempted to identify the canine COMT gene fragment and to find a similar polymorphism and to reveal its genetic distribution among five representative canine breeds. We found that the amplified gene consisted of 663 bp nucleotides and was 84% homologous with the human COMT gene. The single nucleotide polymorphisms, guanine adenine substitution, were observed at the 39th, 216th and 482nd nucleotides. From the genotyping of the 216th polymorphism among 266 dogs by the polymerase chain reaction-restriction fragment length polymorphism method with restriction enzyme EagI, and that of the 482nd polymorphism with restriction enzyme SfcI, we found inter-breed variations of genotypes as well as of allelic frequencies for both of these polymorphic regions. These results suggest that the identified polymorphisms will be useful tools in elucidating the genetic background of canine behavioral traits.  相似文献   
163.
To determine the characters of receptors on target cells for avian rotaviruses, the receptors on MA104 cells for the pigeon rotavirus PO-13, the turkey rotaviruses Ty-1 and Ty-3, and the chicken rotavirus Ch-1 were analyzed. Pretreatment of MA104 cells with neuraminidase greatly reduced the infection by all of the four avian rotavirus strains. Binding of the cell-attachment protein, purified VP8 expressed in bacteria, of strain PO-13 to MA104 cells was also inhibited by pretreatment of cells with neuraminidase. These findings suggest that avian rotaviruses primarily utilize sialic acid-containing molecules as receptors on MA 104 cells.  相似文献   
164.
Differentiation of the histochemical characteristics of the olfactory receptor cells (ORC) was examined by immunohistochemistry for protein gene product 9.5 (PGP 9.5) and calretinin (CR) and lectin histochemistry for Phaseolus vulgaris agglutinin-L (PHA-L) in the developing olfactory epithelium (OE) of the barfin flounder. PGP 9.5 immunoreactivity was diffuse and CR immunoreactivity was restricted at day 7, but these immunoreactivities became intense in the OE toward day 91. Crypt cells were first identified at day 56. PHA-L staining was faint at day 28, but became intense toward day 91. These findings suggest that PGP 9.5-immunopositive cells, CR-immunopositive cells, crypt cells and PHA-L-reactive cells differentiate independently in the developing OE and constitute subsets of the ORC in the OE.  相似文献   
165.
This paper describes the isolation of porcine epidemic diarrhea (PED) virus in Vero and porcine cell cultures, and the influence of age on disease in experimental infection. PED virus was isolated from the small intestine of piglets inoculated with PED samples and cultured in Vero, porcine bladder and kidney cells propagated in collagen-coated tissue culture plates in maintenance medium (MM) containing trypsin. In porcine bladder and kidney cell cultures inoculated with isolated PED virus, cytopathic effects (CPE) including cell fusion were detected. Specific brilliant fluorescence was observed in the cytoplasm of these cells. Two- and 7-day old, and 2-, 4-, 8- and 12-week old specific pathogen-free (SPF) pigs were orally inoculated with PED virus isolated from an outbreak. All 2- and 7-day old pigs inoculated developed severe watery diarrhea from post-inoculation day (PID) 1 and died between PID 3 and 4. Although three of five 2-week old pigs developed diarrhea on PID 1-4, they eventually recovered. In the 4-week old group, three of five pigs had mild diarrhea for 1-2 days. None of the 8- and 12-week old pigs showed any clinical signs. Antibodies against PED virus were detected in all surviving pigs by virus neutralization (VN) test and immunofluorescence assay (IFA). Therefore, there is an age-dependent resistance to pathogenic PED virus infection in pigs.  相似文献   
166.
167.
Analysis of cellular components at multiple levels of biological information can provide valuable functional insights. We performed multiple high-throughput measurements to study the response of Escherichia coli cells to genetic and environmental perturbations. Analysis of metabolic enzyme gene disruptants revealed unexpectedly small changes in messenger RNA and proteins for most disruptants. Overall, metabolite levels were also stable, reflecting the rerouting of fluxes in the metabolic network. In contrast, E. coli actively regulated enzyme levels to maintain a stable metabolic state in response to changes in growth rate. E. coli thus seems to use complementary strategies that result in a metabolic network robust against perturbations.  相似文献   
168.
Amination of alkanes has generally required metal catalysts and/or high temperatures. Here we report that simple exposure of a broad range of alkanes to N-triflylimino-λ(3)-bromane 1 at ambient temperature results in C-H insertion of the nitrogen functionality to afford triflyl-substituted amines in moderate to high yields. Marked selectivity for tertiary over secondary C-H bonds was observed; primary (methyl) C-H bonds were inert. Addition of hexafluoroisopropanol to inhibit decomposition of 1 dramatically improved the C-H amination efficiencies. Second-order kinetics, activation parameters (negative activation entropy), deuterium isotope effects, and theoretical calculations suggest a concerted asynchronous bimolecular transition state for the metal-free C-H amination event.  相似文献   
169.
Floral biology, pollen germination, and scanning electron microscopy studies have indicated different types of pollen within the same flower in at least two species of New World Lecythidaceae, subfamily Lecythidoideae. Two types of pollen are produced in different parts of the androecium and serve different functions. One type attracts pollinators by providing a reward, and the other functions in fertilization. The former type has lost its ability to germinate, at least under in vitro conditions.  相似文献   
170.
Perilla (Lamiaceae) contains one tetraploid species, P. frutescens (L.) Britt. and three diploid species, P. citriodora (Makino) Nakai, P. hirtella Nakai and P. setoyensis G. Honda. Tetraploid species have been traditionally cultivated in Asia for their seed oil and for their fragrant leaves that are used as medicine or as a garnish for fish. The center of diversity is still obscure. To conserve the genetic resources, it is important to know the diversity of the tetraploid species. The three diploid species, which are possible parents of the tetraploid species, are all believed to be indigenous to Japan. Their distribution in China and Korea was clarified on the basis of herbarium and field surveys. The tetraploid species is assumed to have originated somewhere around the mid-to downstream area of the Changjiang River. Though Perilla is not cultivated as often in these areas as in northern China, Korea, the Himalayan region, or Myanmar, these areas should also be important for the conservation of genetic resources of tetraploid Perilla crops because of the expected high genetic diversity.  相似文献   
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