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531.
We investigated the relationship between plasma vitamin C concentration and serum levels of some diagnostic biochemical markers in 118 lactating Holstein cows. Blood sample was collected once from each cow and we measured the plasma vitamin C concentration and the serum levels of glucose, beta-hydroxybutyrate, free fatty acids, triacylglycerol, total cholesterol, albumin, total bilirubin, alkaline phosphatase, aspartate aminotransferase and gamma-glutamyltransferase. The regression of plasma vitamin C with each serum diagnostic biochemical marker indicated that the vitamin C concentration significantly decreased as glucose, alkaline phosphatase or aspartate aminotransferase level increased and as total cholesterol or albumin concentration decreased. Furthermore, the plasma vitamin C concentration was significantly lower in the cows showing that each of these marker levels was out of its reference interval than in the cows showing that the marker level was within its reference interval. The significant correlations were observed among total cholesterol, albumin, alkaline phosphatase and aspartate aminotransferase levels, to which the glucose concentration was not related. These results showed that the plasma vitamin C concentration was low in the cows that had concurrently low levels of total cholesterol and albumin, and high levels of alkaline phosphatase and aspartate aminotransferase. Therefore, a hepatic malfunction possibly decreases plasma vitamin C concentration through suppressing vitamin C production. On the other hand, the high level of glucose possibly decreases plasma vitamin C concentration through suppressing vitamin C recycling.  相似文献   
532.
533.
An epidemiological survey of bovine Setaria collected from the abdominal cavities was performed morphologically on the cattle in Aomori and Kumamoto Prefectures, Japan, between August 2005 and July 2006. Fifty Setaria worms were collected from the cattle in Aomori Prefecture and 847 from those in Kumamoto Prefecture. Of these worms, 35 were identified as Setaria digitata, 14 as S. marshalli, and one as S. labiatopapillosa in Aomori Prefecture, while 816 were identified as S. digitata and 31 as S. marshalli in Kumamoto Prefecture.  相似文献   
534.
We attempted to isolate Listeria monocytogenes from skin, contents of large intestines and carcasses of cattle introduced to a slaughterhouse in order to identify source of contamination for this pathogen. Sixty skin samples, 60 samples of the contents of large intestines and 30 carcass samples were colleted in June, August and November 2003 for use in this study. Listeria spp. and L. monocytogenes were isolated from 30 (50%) and 3 (5%) of the cattle skin samples, respectively. However, no Listeria spp., including L. monocytogenes, were isolated from intestinal contents or carcasses. Seven isolates were obtained, of which five and two strains were serotypes 1/2a and 1/2b, respectively. Genetic analysis suggested that there was persistent inhabitation of the pathogen around the area investigated in this study.  相似文献   
535.
To clarify the geographic variation and isolate specificity in blast resistance, 20 cultivars of foxtail millet (Setaria italica (L.) P. Beauv.) originating from Eurasia were examined for their resistance using 11 Japanese Setaria isolates of blast fungus. Cultivars from the countries east of Pakistan generally showed resistance to most of the 11 fungus isolates, whereas those from the countries west of Afghanistan indicated higher susceptibility. The origin of this geographical regularity was discussed in relation to the deficiency or specificity of relevant resistance gene(s). No identical reaction pattern was observed among cultivars, indicating their highly distinctive isolate specificity. The virulence of isolates was also diverse, since only 2 out of 10 virulent isolates were identical for their reaction patterns. Preliminary genetic analysis of blast resistance to four fungus isolates suggests that they are governed by more than two dominant genes.  相似文献   
536.
To examine the metabolic fate of 7-fluoro-6-(3,4,5, 6-tetrahydrophthalimido)-4-(2-propynyl)-2H-1,4-benzoxazin-3( 4H)-one (S-53482), rats were given a single oral dose of [phenyl-(14)C]-S-53482 at 1 (low) or 100 (high) mg/kg. The radiocarbon was almost completely eliminated within 7 days after administration in both groups. (14)C recoveries (expressed as percentages relative to the dosed (14)C) in feces and urine were 56-72 and 31-43%, respectively, for the low dose and 78-85 and 13-23%, respectively, for the high dose. S-53482 and seven metabolites were identified in urine and feces. Six of them were purified by several chromatographic techniques and identified by spectroanalyses (NMR and MS). Alcohol derivatives and an acetoanilide derivative were isolated from urine. Three sulfonic acid conjugates having a sulfonic acid group incorporated into the double bond of the 3,4,5,6-tetrahydrophthalimide moiety were isolated from feces. On the basis of the metabolites identified in this study, the metabolic pathways of S-53482 in rats are proposed.  相似文献   
537.
alpha-Glucosidase (AGH) inhibitory study by natural anthocyanin extracts was done. As the result of a free AGH assay system, 12 anthocyanin extracts were found to have a potent AGH inhibitory activity; in particular, Pharbitis nil (SOA) extract showed the strongest maltase inhibitory activity, with an IC(50) value of 0.35 mg/mL, as great as that of Ipomoea batatas (YGM) extract (IC(50) = 0.36 mg/mL). Interestingly, neither extract inhibited the sucrase activity at all. For the immobilized assay system, which may reflect the pharmacokinetics of AGH at the small intestine, SOA and YGM extracts gave more potent maltase inhibitory activities than those of the free AGH assay, with IC(50) values of 0.17 and 0.26 mg/mL, respectively. Both extracts also inhibited alpha-amylase action, indicating that anthocyanins would have a potential function to suppress the increase in postprandial glucose level from starch.  相似文献   
538.
A method is described for the determination of inorganic tin in biological samples by hydride generation-atomic absorption spectrometry (HG-AAS). A sample is extracted with ethyl acetate after addition of HCl and NaCl. The concentrated extract is passed through a silica gel column. The column is washed with ethanol, water, and 0.2N HCl successively, and then inorganic tin is eluted with 2N HCl and measured by HG-AAS. Recoveries from fish muscle spiked with 0.1 micrograms/g Sn4+ are 78.9 +/- 4.2% (average +/- standard deviation, n = 5). The detection limit is 0.01 micrograms/g as Sn.  相似文献   
539.
540.
The aim of the present study was to investigate the protective effects of Ganoderma lucidum polysaccharide (GLPS) against carbon tetrachloride (CCl4)-induced hepatotoxicity in vitro in common carp. Precision-cut liver slices (PCLSs), which closely resemble the organ from which they are derived, were employed as an in vitro model system. GLPS (0.1, 0.3, and 0.6 mg/ml) was added to PCLS culture system before the exposure to 12 mM CCl4. The supernatants and slices were collected to detect molecular and biochemical responses to CCl4 and PCLS treatments. The levels of CYP1A, CYP3A, and CYP2E1 were measured by ELISA; the mRNA expressions of TNF-α, IL-1β, IL-6, and iNOS were determined by RT-PCR; and the relative protein expressions of c-Rel and p65 were analyzed by western blotting. Results showed that GLPS inhibited the elevations of the marker enzymes (GOT, GPT, LDH) and MDA induced by CCl4; it also enhanced the suppressed activity of antioxidant enzymes (SOD, CAT, GSH-Px, T-AOC). The treatment with GLPS resulted in significant downregulation of NF-κB and inflammatory cytokine mRNA levels and significant decreases in the hepatic protein levels of CYP1A, CYP3A, and CYP2E1. These results suggest that GLPS can protect CCl4-induced PCLS injury through inhibiting lipid peroxidation, elevating antioxidant enzyme activity, and suppressing immune inflammatory response.  相似文献   
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