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81.
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Response of bovine and porcine peripheral blood mononuclear cells to human recombinant interleukin 2(125) 总被引:1,自引:0,他引:1
Bovine and porcine peripheral blood mononuclear cells (PBMC) were tested for their response to human recombinant interleukin 2(125) (rIL 2(125)). The rIL 2(125) used in these experiments was purified to homogeneity from Escherichia coli, contained a site-specific modification at amino acid #125 replacing a cysteine with a serine residue and had a specific activity of 4 X 10(6) units/mg. Human rIL 2(125) was shown to be directly mitogenic for bovine and porcine PBMC and was able to maintain the long-term growth of mitogen-activated PBMC of both species. Long-term cultures were highly sensitive to low levels of rIL 2(125) and showed dose-dependent responses when used in short-term IL 2 assays. Bovine and porcine PBMC preincubated with human rIL 2(125) for 1 and 5 days demonstrated enhanced levels of cell-mediated cytotoxicity against both allogeneic and xenogeneic cell lines. 相似文献
84.
Chen SN Friesen JB Webster D Nikolic D van Breemen RB Wang ZJ Fong HH Farnsworth NR Pauli GF 《Fitoterapia》2011,82(4):528-533
A new labdane-diterpene, viteagnusin I (1), together with 23 known phytoconstituents were isolated from the fruits of Vitex agnus-castus L, and their structures characterized by spectroscopic methods (NMR and MS). The known compounds include ten flavonoids, five terpenoids, three neolignans, and four phenolic compounds, as well as one glyceride. Biological evaluation identified apigenin, 3-methylkaempferol, luteolin, and casticin as weak ligands of delta and mu opioid receptors, exhibiting dose-dependent receptor binding. 相似文献
85.
R. E. Hueter W. G. Fong G. Henderson M. F. French C. A. Manire 《Water, air, and soil pollution》1995,80(1-4):893-899
The concentrations of methylmercury (MeHg) in 124 samples of muscle taken from nine species of common sharks of varying sizes and locations along the Florida coast were determined. Muscle MeHg levels averaged 0.88 μg/g (wet sample basis) and ranged from 0.06 to 2.87 μg/g, with 33.1% of the samples exceeding the U.S. Food and Drug Administration's 1 μg/g action level. Differences were found in MeHg concentration by species but not by sex. A positive correlation between MeHg levels and shark size was found such that most sharks larger than approximately 200 cm total length contained MeHg concentrations exceeding the 1 μg/g action level. Fetal sharks contained consistently lower MeHg levels than their mothers. Sharks collected off southern regions of the state contained significantly higher MeHg concentrations than those off the northeast coast. The human health concerns for consumers of Florida shark meat are discussed in relation to these findings. 相似文献
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87.
Increased activity of calcium leak channels in myotubes of Duchenne human and mdx mouse origin 总被引:25,自引:0,他引:25
Elevated free Ca2+ concentrations found in adult dystrophic muscle fibers result in enhanced protein degradation. Since the difference in concentrations may reflect differences in entry, Ca2+ leak channels in cultures of normal and Duchenne human myotubes, and normal and mdx murine myotubes, have been identified and characterized. The open probability of leak channels is markedly increased in dystrophic myotubes. Other channel properties, such as mean open times, single channel conductance, ion selectivity, and behavior in the presence of pharmacological agents, were similar among myotube types. Compared to the Ca2+ concentrations in normal human and normal mouse myotubes, intracellular resting free Ca2+ concentrations ([Ca2+]i) in myotubes of Duchenne and mdx origin were significantly higher at a time when dystrophin is first expressed in normal tissue. Taken together, these findings suggest that the increased open probability of Ca2+ leak channels contributes to the elevated free intracellular Ca2+ concentration in Duchenne human and mdx mouse myotubes. 相似文献
88.
PE Fernández ME Diessler A Pachame HH Ortega EJ Gimeno EL Portiansky CG Barbeito 《Reproduction in domestic animals》2014,49(2):263-269
The aim of this study was to characterize cytoskeletal intermediate filament proteins and glycoconjugates of syncytiotrophoblast, cytotrophoblast and decidual cells of feline endotheliochorial placenta. Samples from 12 normal pregnant female cats, after 45 ± 5 days of gestation, were obtained removing the uterine horns by hysterectomy. Sections were processed for routine observation and for immunohistochemistry using anticytokeratin, antivimentin and antidesmin antibodies. In addition, lectin histochemistry was performed using a panel of several biotinylated lectins to characterize glycosides expression profile. Cytotrophoblast and syncytiotrophoblast showed immunoreactivity only with acidic and basic cytokeratins. Decidual cells were only positive to vimentin, consistent with their origin from endometrial fibroblasts. Trophoblast expressed a broad population of glycans, highly exposing terminal N‐acetyl glucosamine residues and non‐sialylated galactose and N‐acetyl galactosamine oligomers. Oligosaccharides bound by Phaseolus vulgaris erythroagglutinin were the only highly branched N‐linked residues evidenced in cats, and they were restricted to the syncytium. Unlike results reported on humans, mice and rats on lectin affinity of decidual cells, sialid acids and complex N‐linked oligosaccharides were not demonstrated in cats. Glycosylation of proteins determines many of their final properties, thus becoming essential for the embryo‐maternal dialogue during implantation and placentation. Changes in glycosylation pattern have been related to pathological pregnancies in other species. Hence, the knowledge about glycosylation profile of the normal cat placenta may lead to a better understanding of both normal and pathological reproductive events. 相似文献
89.
H. Rahardjo F.R. Harnas I.G.B. Indrawan E.C. Leong P.Y. Tan Y.K. Fong L.F. Ow 《Urban Forestry & Urban Greening》2014,13(2):355-364
There have been several cases of tree failure in Singapore. Many studies have shown that soil properties and root architecture of trees are important factors that govern tree stability. Twenty Samanea saman trees were planted in different soil media, which were original in situ soil, top soil, mixture of 50% granite chips and 50% top soil, and mixture of 80% granite chips and 20% top soil. The objectives of this study were to investigate tree overturning processes and also to compare the results of tree pulling tests with results from an analytical calculation and numerical modeling for different soil types. The results showed that stability of the trees were not governed by the shear strength of the soil. Factors that affected tree stability included cross-sectional area of the roots and root plate area. Tree pulling test and numerical modeling results showed that there were two modes of failure which occurred when a tree was overturned. The first mode was the shear failure of soil and the second was a combination of shear failure of soil and root breakage. The maximum overturning force obtained from the tree pulling test was in the same order of magnitude as the maximum overturning forces obtained from the analytical calculation and numerical modeling. 相似文献
90.
G Pedrana MH Viotti E Souza D Sloboda GB Martin D Cavestany HH Ortega 《Reproduction in domestic animals》2013,48(5):795-802
Pre‐natal glucocorticoids are used in women at risk of preterm delivery to induce foetal lung maturation. However, glucocorticoids can produce negative outcomes for other tissues such as the reproductive system. We therefore tested the effects of pre‐natal betamethasone on testicular morphology and apoptotic protein immune expression during pre‐ and post‐natal development. Pregnant ewes (n = 42) bearing singleton male foetuses were randomly allocated to receive intramuscular injections of saline or betamethasone (0. 5 mg/kg) at 104, 111 and 118 days of gestation (DG). Testes were collected at 121 and 132 DG, and at 45 and 90 post‐natal days (PD) and subjected to morphometric analysis (volume densities of sex cords and interstitial tissues; sex cord diameter). Immunohistochemistry (% stained area) was used to assess active caspase‐3, Bax, Bcl‐2 and cell‐cycle proteins (PCNA). Compared with control values, betamethasone treatment decreased sex cord diameter at 121 DG, 45 and 90 PD, and sex cord volume at 90 PD. Active caspase‐3 was decreased by betamethasone at 121 DG and 90 PD, but Bax was increased in all betamethasone groups. Bcl‐2 and PCNA decreased in the betamethasone groups at 121 DG and 45 PD, but increased at 132 DG and 90 PD. We conclude that high levels of pre‐natally administered glucocorticoid reduce foetal testicular development, perhaps via changes in the balance between pro‐ and anti‐apoptotic proteins and cell‐cycle proteins. These outcomes could compromise the future spermatogenic potential of male offspring. 相似文献