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201.
The effect of dietary administration of bananas on immunocytes in calves was investigated. Twenty Fl hybrid calves were used in this study (treated group n=10, control group n=10). Banana (2 g/kg BW) was administered to the calves for 5 days. Leukocyte subsets were examined on days 0, 5, 10, and 15. The numbers CD3+, (CD3+)CD45R-, and (CD3+)TcR+ cells significantly increased between day 0 and day 5 in the treated group (P<0.01), and were significantly higher on day 5 in the treated group relative to the control group (P<0.05). These data showed that feeding banana to calves increased T-lymphocytes, suggesting it might be possible to enhance protective functions against infections.  相似文献   
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To clarify muscle type‐specific effect of myostatin on myogenic regulatory factors (MRFs), we examined mRNA expression of MRFs in five skeletal muscles of normal (NM) and myostatin‐deficient double‐muscled (DM) adult Japanese Shorthorn cattle by quantitative reverse‐transcribed PCR. Among the four MRFs, namely, Myf5, MyoD, myogenin, and MRF4, MyoD expression was different among the muscles of the DM cattle (P < 0.01) but not of the NM cattle. Meanwhile, MyoD expression was significantly elevated only in masseter (MS) muscle in the DM cattle due to the myostatin deficiency (P < 0.05). Myf5 and MRF4 expression in semitendinosus (ST) was higher in the DM than in the NM cattle (P < 0.05). According to analysis of myosin heavy chain (MyHC) isoform expression, more MyHC‐2x and ‐2a and less ‐slow isoforms were expressed in the longissimus and ST muscles compared to the MS muscle in both cattle (P < 0.05), but no significant difference in MyHC expression was observed between the NM and DM cattle. Taken together, myostatin has influences on Myf5 and MRF4 expression in faster‐type muscles and on MyoD expression in slower‐type muscles, suggesting a possible muscle type‐specific effect of myostatin in skeletal muscle growth and maintenance.  相似文献   
205.
The agronomic benefits of manure application to increase rice production have been recognized, but the impact on global change has always been a controversial topic. This study was designed to determine the separate and combined effects of cattle manure (CM) and nitrogen (N) fertilizer on rice yield, N efficiency, and methane (CH4) emissions from rice cultivation. A pot-scale experiment was conducted with four levels (0, 60, 120, and 180 kg ha?1) of N from urea and two levels (120 and 180 kg ha?1) of N from combination of urea and CM (Urea:CM = 60:60 and 60:120). Rice yield and physiological N efficiency were obtained using agronomic measurements. To determine the global warming potential (GWP) of each treatment, CH4 emissions were measured throughout the rice-growing period. Grain yield (GY) was not significantly different between the treatments of 120 and 180 kg ha?1 regardless of N source. However, both rates of CM treatments enhanced CH4 emission and differences in GWP were significant. In conclusion, urea applied at 120 kg N ha?1 was optimal for rice productivity and environmental impact (EI) despite CM played a crucial role in improving the N efficiency and total N in the soil after harvest.  相似文献   
206.
To search for an index for chemical composition related to superior taste in Japanese Black beef, we conducted panel tests and analyzed the chemical composition of seven beef brands. Thirty‐five sirloin beefs from five heifers were used in this study, sold under seven beef brands graded as more than A4 on the Japanese Meat Grade scale. The chemical composition analyses assessed both raw and roasted meat, the latter of which was roasted under the same conditions as those used for the panel test. Results of the panel test and chemical composition analyses revealed that fatty acid composition, sugar content, adenosine triphosphage (ATP)‐related compounds, amino acid composition and odor composition in the sirloin meat differed among beef brands. Furthermore, the correlations of chemical compositions between roasted and raw meat were significantly high. Sugar content and ATP‐related compounds in roasted meat were significantly correlated with the item ‘overall evaluation’ of the panel test. ATP‐related compounds, such as inosinic acid, carnosine and taurine, in roasted and raw meat were correlated significantly with the item ‘umami intensity’ of the panel test. These results suggest that the composition of these components is important for an index related to the overall evaluation of beef.  相似文献   
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The leptin receptor (LEPR) gene is considered a candidate gene for fatness traits. It is located on SSC 6 in a region in which quantitative trait loci (QTLs) for backfat thickness (BF), fat area ratios, and serum leptin concentration (LEPC) have previously been detected in a Duroc purebred population. The objectives of the present study were to identify porcine LEPR polymorphisms and examine the effects of LEPR polymorphisms on fatness traits in this same population. The Duroc pigs (226 to 953 pigs) were evaluated for BF, fat area ratios using image analysis, and LEPC. A total of seven single nucleotide polymorphisms (SNPs) in the full‐length LEPR coding region were identified in pigs from the base population. Four non‐synonymous SNPs of the LEPR gene and 15 microsatellite markers on SSC 6 were then genotyped in all pigs. During candidate gene analysis, we detected significant effects of the non‐synonymous SNP c.2002C>T in exon 14 on all traits. In fine mapping analysis, significant QTLs for BF, fat area ratios, and LEPC were detected near the LEPR gene in the same region. These results indicated that the c.2002C>T SNP of LEPR has a strong effect on BF, fat area ratios and LEPC.  相似文献   
208.
A disease characterized by arthritis of carpal joints and occasionally by pneumonia was seen among goats on a farm in Nagano prefecture of Japan in the summer of 2002. Serological investigation was done on 30 goats, that is one group on the farm by agar gel immunodiffusion tests using maedi-visna virus as the antigen, and 19 goats were positive. The caprine arthritis encephalitis virus genome was detected in peripheral blood leukocytes from several antibody-positive goats. Two goats among them were necropsied and used for pathological tests and virus isolation. The isolated virus was serially propagated in fetal lamb lung cell cultures. Goats inoculated with the culture fluid became antibody positive. These results suggested that a CAEV-infected goat had been introduced accidentally to the farm and that subclinical infection occurred among the flock.  相似文献   
209.
The traditional method of processing fish waste is costly and usually overheats the waste, making it less digestible. In the present study, a fermentation technique using Aspergillus awamori was used to dry minced sardine fish to find a new model for processing fish waste and to evaluate its digestibility. Wheat bran (700 g), minced fresh sardines (2638 g) and A. awamori spores (0.7 g) were mixed together and kept in a ventilated incubator for 5 days at 40°C. At the end of the fermentation, a sample of fishmeal was taken to measure the nutrient content, enzyme activity and digestibility of crude protein (CP) and dry matter (DM) using an in vitro method. Furthermore, the effect of enzymes produced during the fermentation of DM and CP digestibilities of corn–soybean mixture in vitro were also examined. The percentage of moisture, CP, crude fat and nitrogen‐free extract in the fermented fish waste were 11, 39, 23 and 25%, respectively. The in vitro digestibilities of DM (69%) and CP (84%) of the fishmeal were almost the same as those of the heat‐dried sardine powder. During the fermentation, glucoamylase, α‐glucosidase, α‐amylase and acidic protease were produced, which may improve the DM digestibility of the diet. In conclusion, fish waste can be dried successfully using the fermentation technique described in the present study. Furthermore, the DM digestibility of the corn–soybean meal mixture is improved by the enzymes produced during the fermentation.  相似文献   
210.
OBJECTIVE: To determine the effects of interleukin (IL)-1 and tumor necrosis factor (TNF)-alpha on canine chondrocytes cultured in an agarose-based 3-dimensional (3-D) system. SAMPLE POPULATION: Humeral head articular cartilage chondrocytes obtained from 6 adult dogs. PROCEDURE: Chondrocytes were cultured in a 3-D system for < or = 12 days in serum-free medium with IL 1alpha, IL-1beta, or TNF-alpha at concentrations of 20, 50, or 100 ng/mL. After 1, 3, 6, and 12 days, glycosaminoglycan (GAG) concentrations in 3-D constructs; nitric oxide and prostaglandin E2 (PGE2) concentrations in media samples; and relative expressions of selected genes, including metalloproteinase (MMP)-13 and tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2, were evaluated. Control specimens were comprised of chondrocytes cultured without proinflammatory cytokines. RESULTS: In control 3-D constructs, GAG content was significantly higher than for all other constructs. Compared with control values, relative expressions of MMP-13, TIMP-1, and TIMP-2 genes in the IL-1beta (50 ng/mL) group were significantly higher at day 1; at all evaluations, media concentrations of nitric oxide were significantly higher in all TNF-alpha-treated cultures; and concentrations of PGE2 in media samples were significantly higher in the IL-1beta (50 ng/mL) and IL-1beta (100 ng/mL) groups at days 1 and 3, in the IL-1beta (100 ng/mL) group at day 6, and in all TNF-alpha groups at days 1, 3, and 6. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that TNF-alpha more readily induces production of nitric oxide and PGE2 by canine chondrocytes, compared with IL-1beta. In vitro, IL-1alpha appeared to have a minimal effect on canine chondrocytes.  相似文献   
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