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41.
To investigate the influence of maternal Se supply and plane of nutrition on lamb morbidity, mortality, and passive transfer of IgG, pregnant ewe lambs were used in 2 experiments with 2 × 3 factorial treatment arrangements. Supplementation of Se began at breeding and was either adequate Se (ASe, 9.5 μg/kg of BW) or high Se (HSe, 81.8 μg/kg of BW) in Exp. 1 or ASe (11.5 μg/kg of BW) or HSe (77.0 μg/kg of BW) in Exp. 2. On d 50 or 40 of gestation for Exp. 1 or 2, respectively, ewes were assigned randomly to 1 of 3 nutritional planes: 60% (RES), 100% (control, CON), or 140% (HI) of NRC requirements. This resulted in the following treatments: ASe-RES, ASe-CON, ASe-HI, HSe-RES, HSe-CON, and HSe-HI. Upon parturition, lambs were separated from their dams and serum samples obtained. Lambs were fed artificial colostrum for the first 20 h and then placed on milk replacer and grain pellets until completion of the study (Exp. 1, 57 d; Exp. 2, 21 d). Twenty-four hours after parturition, lamb serum samples were collected for IgG analysis. All lambs were reared similarly and morbidity and mortality assessed. Main effects were considered significant when P ≤ 0.05. In Exp. 1, there was a Se × plane of nutrition interaction (P ≤ 0.01) for lamb morbidity from birth to weaning and for 24-h IgG concentration. Lambs from ASe-RES and HSe-HI ewes were treated more frequently (P < 0.01) for respiratory and gastrointestinal disease, and lambs from HSe-HI ewes had the smallest (P < 0.01) 24-h serum IgG concentration. In Exp. 1, lambs from HI ewes also had the greatest (P < 0.01) mortality rates from birth to weaning compared with lambs from CON and RES ewes. In Exp. 2, there was an effect (P < 0.01) of maternal plane of nutrition with lambs from RES ewes having increased 24-h IgG compared with lambs from CON and HI ewes. There was no effect of maternal Se supplementation on lamb 24-h IgG in Exp. 2; however, there was a Se × plane of nutrition interaction (P < 0.01) for morbidity. From birth to 21 d of age, lambs from ASe-CON ewes had fewer (P < 0.01) treatment days compared with lambs from any of the other treatment groups. There also tended (P = 0.08) to be an effect of maternal Se supplementation on lamb mortality with increased mortality observed in lambs from HSe ewes. Results from the studies show a restricted maternal plane of nutrition can increase lamb serum IgG concentration. Selenium results were not consistent between the 2 experiments and may be due to differences in maternal Se.  相似文献   
42.
OBJECTIVE: To determine whether expression of G proteins (G(i) and G(s)) is altered in thyroid gland adenomas obtained from hyperthyroid cats. SAMPLE POPULATION: Adenomatous thyroid glands obtained from 8 hyperthyroid cats and thyroid glands obtained from 4 age-matched euthyroid cats. PROCEDURE: Expression of G(i) and G(s) was quantified in enriched membrane preparations of thyroid gland tissue, using immunoblotting with G(i) and G(s) antibodies and toxin-catalyzed ADP-ribosylation. RESULTS: Expression of G(i) was significantly reduced in thyroid gland adenomas from hyperthyroid cats, compared with normal thyroid gland tissue from euthyroid cats. Expression of G(s) was similar between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE: A decrease in expression of G in adenomatous thyroid glands of cats may reduce the negative inhibition of the cAMP cascade in thyroid cells, leading to autonomous growth and hypersecretion of thyroxine. Understanding the molecular mechanisms for hyperthyroidism in cats may lead to better treatment or, ultimately, prevention of the disease.  相似文献   
43.
Twenty-four dogs and 30 cats with histopathologically confirmed salivary gland neoplasia were retrospectively reviewed in a multi-institutional study. The predominant presenting complaint for animals with salivary gland neoplasia was that of a mass being noted by the owner; other common complaints included halitosis, dysphagia, and exophthalmia. Siamese cats were overrepresented, indicating a possible breed predisposition. The most common histopathological type was simple adenocarcinoma. Cats had more advanced disease at diagnosis than did dogs, and clinical staging was prognostic in dogs. The median survival times for dogs and cats were 550 days and 516 days, respectively.  相似文献   
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In this paper we characterize the metabolic fingerprint and first reported anti-inflammatory activity of Hypericum gentianoides. H. gentianoides has a history of medical use by Native Americans, but it has been studied very little for biological activity. High-performance liquid chromatography (HPLC) and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analyses of a methanol extract show that H. gentianoides contains a family of over nine related compounds that have retention times, mass spectra, and a distinctive UV absorption spectra characteristic of certain acyl-phloroglucinols. These metabolites are abundant relative to other secondary products present in H. gentianoides, accounting for approximately 0.2 g per gram of dry plant tissue. H. gentianoides methanol extracts and a specific semipreparative HPLC fraction from these extracts containing the putative acyl-phloroglucinols reduce prostaglandin E 2 synthesis in mammalian macrophages.  相似文献   
47.
The changes of Eh and pH in soil suspension (Ah-horizon of a Mollic Gleysol) and Mn2+ or Fe2+ concentrations in the equilibrium soil solution at different levels of glucose (0%, 0.5% and 1%) and MnO2 (0%, 0.025%, 0.05% and 0.1%) or Fe2O3 (0%, 0.025%, 0.05% and 0.1%) were examined. It was found that the degree of Mn- and Fe-reduction in soil depends mainly on the presence and the amount of an easily decomposable carbon source and to a minor degree on the content of native or added forms of MnOO2 or Fe2O3 in the soil. Theoretical relationships between the water soluble manganese and iron and the Eh and pH values have been verified, when the observed initial drop of Eh was eliminated. It was found that the water soluble manganese content was described best by the Mn2O3/Mn2+ redox system, and that of iron by the Fe3 (OH)3/Fe2+ system.  相似文献   
48.
The traditional whedo system involves the digging of large ditch-like ponds that fill seasonally with flood water, trapping fish which are subsequently harvested during the dry season. Although whedos are well described in the South of Benin, basic information necessary for their management in the North is lacking. Since 1998, the commune of Malanville has experienced a kind of ‘blue revolution’ because up to now, approximately 500 whedos (known locally as tschifi dais) have been constructed covering a total surface area of 9.3 ha, thus reflecting the high acceptance of the practice among the local population. Despite the fast development this system has received little attention from national development planners and international agencies, but in view of the disastrous state of the river Niger's fishery, sustainable aquaculture, fully relying on local species should be supported to release pressure on natural fish stocks. Instead of focussing all efforts on the introduction of modern aquaculture, it is important to enhance the existing system because of the knowledge and acceptance by the local population.

This paper characterizes the current management and the technical as well as economical features of the tschifi dais in the commune of Malanville, northern Benin.  相似文献   
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The objectives of this work were to evaluate how dietary soybean meal (SBM) or a soy meal made by bioprocessing the SBM (BPSBM) to remove anti-nutritional factors affected hydrolytic capacity, amino acid absorption, intestinal morphology, and microflora along the intestinal tract of Atlantic cod at two life stages. Three fish meal based standard cod diets were formulated to contain no soy (FM control), 25% SBM, or 22% BPSBM. Prior to sampling the diets were fed to duplicate groups of 0.5 kg (1-year old) and 1.7 kg (2-year old) cod for a period of 3 months, and the groups reached 0.9 and 2.5 kg, respectively. Digesta was then sampled from different intestinal sections for analyses of trypsin and amylase activity as well as absorption of amino acids, nitrogen, and sulphur. Gastrointestinal sections were sampled for measurements of relative weight (kg− 1 body weight), and tissues from these sections were sampled for analyses of brush border enzyme (alkaline phosphatase (ALP), leucine aminopeptidase (LAP), and maltase) activity and histological examination. Microflora was sampled from both digesta and the intestinal wall. The SBM diet stimulated relative growth of all gastrointestinal sections except the distal intestine in both age classes. Relative growth of the pyloric intestine was also stimulated by BPSBM. The pyloric caeca and the upper mid intestine were found to be the major sites for enzymatic hydrolysis of protein and starch and for amino acid absorption. Dietary SBM and BPSBM did not alter the activity of trypsin and LAP, but the activity of these enzymes in the proximal intestine was affected by age, being higher in 1-year old than in 2-year old cod. The rate of amino acid, nitrogen, and sulphur absorption along the gastrointestinal tract was not affected by SBM, but was slowed by BPSBM. Dietary SBM or BPSBM did not alter the morphology of the intestinal mucosa in any sections of the cod intestine. The distal-most structure of the intestine, a compartment with inlet and outlet (anus) valves, showed very high microbial colonisation in the mucosal brush border. Inclusion of SBM in the diet changed the intestinal microflora, increasing the population level of transient bacteria in the pyloric and mid intestine, but reducing the population level of adherent bacteria throughout the intestine. To conclude, Atlantic cod appeared to have a robust and flexible digestive system able to adjust to high dietary levels of soy protein meals.  相似文献   
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