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61.
The nitroblue tetrazolium reduction test (NBT) is an assay based on the activation percentage of neutrophils in peripheral blood, that has been proposed for the follow up of canine leishmaniosis owing to the narrow relationship between the molecules involved in the oxidative burst and the leishmanicidal activity of phagocytes. Domperidone is a drug used for the treatment of canine leishmaniosis having been claimed to stimulate the dogs' cell-mediated immune response. The aim of this study was to evaluate the degree and the lasting of phagocytic activation induced by a 30-day course treatment with Domperidone (0.5 mg/kg/day) in healthy dogs, by using the NBT. A statistically significant increase in the percentages of activated phagocytes was observed in the treated group during treatment, thereafter remaining high for up to one month after the end of treatment. In contrast, untreated dogs maintained the baseline percentage of activated neutrophils all along the study. It is concluded that the NBT is a useful tool for the follow up of the stimulating effects of Domperidone on the neutrophilic response of healthy dogs and that these effects persist for up to one month after treatment with this molecule.  相似文献   
62.
We have engineered a pathway for the formation of disulfide bonds. By imposing evolutionary pressure, we isolated mutations that changed thioredoxin, which is a monomeric disulfide reductase, into a [2Fe-2S] bridged dimer capable of catalyzing O2-dependent sulfhydryl oxidation in vitro. Expression of the mutant protein in Escherichia coli with oxidizing cytoplasm and secretion via the Tat pathway restored disulfide bond formation in strains that lacked the complete periplasmic oxidative machinery (DsbA and DsbB). The evolution of [2Fe-2S] thioredoxin illustrates how mutations within an existing scaffold can add a cofactor and markedly change protein function.  相似文献   
63.

Purpose  

The CQESTR model is a process-based C model recently developed to simulate soil organic matter (SOM) dynamics and uses readily available or easily measurable input parameters. The current version of CQESTR (v. 2.0) has been validated successfully with a number of datasets from agricultural sites in North America but still needs to be tested in other geographic areas and soil types under diverse organic management systems.  相似文献   
64.
A sewage sludge with the addition of two woody materials (1 : 2 ratio), tree-pruning chips and vine shoots, to provide structure were composted under controlled conditions of temperature (28°C) and humidity (70% ambient humidity). Hydrolytic enzyme activities [urease, phosphatase, N-benzoil l-argininamide (BBA) hydrolysing protease, casein-hydrolysing protease, ATP, hydrosoluble and hydrolysable polysaccharides] were determined during the aerobic incubation. Samples were taken and incubated under the same conditions in an accelerative bioreactor to test potential C mineralisation by measuring the CO2 evolved. A rapid mineralisation phase (2–3 weeks) was followed by a slow maturation (4–14 weeks) period. The slow phase and the dynamics of substrate decomposition were better indicated by the hydrolytic enzyme activities that were measured. The structuring agents slightly retarded the compositing process with tree prunings having the strongest effect. Hydrolysable polysaccharides and Folin-reactive compounds (proteins, polyphenols) released by the structure-providing lignocellulose material appear to have controlled both the intensity and the length of the maturation phase.  相似文献   
65.
The sensory and analytical characteristics of five rose sparkling wines manufactured by the traditional method have been determined. Moreover, the changes that take place in the nitrogen and volatile fraction of the wines during the second fermentation and the aging with the yeasts have been studied. Each of these wines was made from a single industrial rose base wine of the Garnacha Tinta variety, with five selected yeasts strains. The base wine had a low content in free amino acids, 16 mg/L, and the yeast consumed more peptides than free amino acids during second fermentation. From the application of the two-way analysis of variance, yeast strain, and aging time factors to the data of volatile compounds, it has been found that most of the differences between these sparkling wines are due to the aging time. It has been verified that these rose sparkling wines have foam of good quality and that the grape variety Garnacha Tinta is suitable for the production of rose sparkling wines.  相似文献   
66.
Some Toll and Toll-like receptors (TLRs) provide immunity to experimental infections in animal models, but their contribution to host defense in natural ecosystems is unknown. We report a dominant-negative TLR3 allele in otherwise healthy children with herpes simplex virus 1 (HSV-1) encephalitis. TLR3 is expressed in the central nervous system (CNS), where it is required to control HSV-1, which spreads from the epithelium to the CNS via cranial nerves. TLR3 is also expressed in epithelial and dendritic cells, which apparently use TLR3-independent pathways to prevent further dissemination of HSV-1 and to provide resistance to other pathogens in TLR3-deficient patients. Human TLR3 appears to be redundant in host defense to most microbes but is vital for natural immunity to HSV-1 in the CNS, which suggests that neurotropic viruses have contributed to the evolutionary maintenance of TLR3.  相似文献   
67.
The first results of the Women's Health Initiative dietary intervention trial were published in the USA in February. This is a colossal intervention designed to see if diets lower in fat and higher in fruits, vegetables and grains than is usual in high-income countries reduce the incidence of breast cancer, colorectal cancer, heart disease and other chronic diseases, in women aged 50-79 years. As interpreted by US government media releases, the results were unimpressive. As interpreted by a global media blitz, the results indicate that food and nutrition has little or nothing to do with health and disease. But the trial was in key respects not reaching its aims, was methodologically controversial, and in any case has not produced the reported null results. What should the public health nutrition profession do about such messes?  相似文献   
68.
We examined the potential antioxidant activity and the immunopharmacological activity of new epicatechin conjugates obtained by depolymerization of grape polymeric flavanols in the presence of cysteamine or cysteine and with or without gallate. The compounds studied were (-)-epicatechin (1), cysteinyl-epicatechin (2), cysteamine-epicatechin (3), (-)-epicatechin gallate (4), cysteinyl-epicatechin gallate (5), and cysteamine-epicatechin gallate (6) When incubated with an erythrocyte suspension, flavanols protected the erythrocyte membrane from hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride, an azo free-radical initiator. All the epicatechin derivatives tested were more efficient as antioxidant than epicatechin. The most potent antioxidant was compound 6. The compounds were tested for their capacity to modulate IL-1beta and IL-6, which are the main cytokine factors influencing the acute phase of the inflammatory response. (-)-Epicatechin and its related compounds inhibited the production of IL-1beta and IL-6 in whole blood incubated in the presence of Escherichia coli lipopolysaccharide. The most efficient inhibitor of cytokine formation was compound 3.  相似文献   
69.
The effect of spray‐dried porcine plasma (SDPP) on the intestinal histological organization and autochthonous microbiota composition was evaluated in Sparus aurata. Fish were fed a basal diet (51 g/kg protein, 17 g/kg fat, 20.6 MJ/kg gross energy) and a diet containing 3 g/kg SDPP for 95 days (initial body weight, BW = 9.5 ± 0.2g, mean ± SD). The inclusion of SDPP promoted growth (p < .05), being fish fed the SDPP diet 6.2% (BW = 88.2 ± 1.6 g) heavier than the control (BW = 82.7 ± 3.2 g). SDPP increased the density of intestinal goblet cells (p < .05), whereas no differences in villi height were found (p > .05) between both groups. Intestinal microbiota was dominated by Proteobacteria (>85%) and Firmicutes (5%–12%), whereas Bacteroidetes never represented more than 1.5%. γ‐Proteobacteria, and Bacilli and Clostridia were the predominant classes. The short administration of SDPP (20 days) resulted in changes in microbiota diversity and richness associated with an increase in the sequences of the genus Lactobacillus and to a decrease in the genus Vibrio, whereas these changes were reverted at 95 days. Intestinal goblet cell density was not correlated to microbiota diversity and richness changes rather than to the immunostimulatory effect of the SDPP.  相似文献   
70.
Demodex mites colonized the hair follicles and sebaceous glands of mammals millions of years ago and have remained relatively unchanged in this protected ecologic niche since then. The host immune system detects and tolerates their presence. Toll‐like receptor‐2 of keratinocytes has been demonstrated to recognize mite chitin and to elicit an innate immune response. The subsequent acquired immune response is poorly understood at present, but there is experimental and clinical evidence that this is the main mechanism in the control of mite proliferation. A transgenic mouse model (STAT?/?/CD28?/?) has demonstrated that the immune response is complex, probably involving both cellular and humoral mechanisms and requiring the role of co‐stimulatory molecules (CD28). It is known that a genetic predisposition for developing canine juvenile generalized demodicosis exists; however, the primary defect leading to the disease remains unknown. Once the mite proliferation is advanced, dogs show a phenotype that is similar to the T‐cell exhaustion characterized by low interleukin‐2 production and high interleukin‐10 and transforming growth factor‐β production by lymphocytes, as described in other viral and parasitic diseases. Acaricidal treatment (macrocyclic lactones) decreases the antigenic load and reverses T‐cell exhaustion, leading to a clinical cure. Although in recent years there have been significant advances in the management and understanding of this important and complex canine disease, more research in areas such as the aetiology of the genetic predisposition and the immune control of the mite populations is clearly needed.  相似文献   
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