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71.
Apoptosis in lymphoid follicles of the ileal Peyer's patch (IPP) in 21 sheep of two different age groups was visualized by the TdT-mediated dUTP nick end-labelling (TUNEL) method, and quantified using computer-assisted image analysis. The IPP follicle carbonic anhydrase (CA) reactivity was evaluated in the same samples. No significant differences with respect to apoptosis and CA reactivity were found between sheep aged 5 and 11 months. Individual variation in apoptotic activity correlated with the follicle centre CA reactivity. The group of animals found to have predominantly atypical ileal lymphoid follicles (more than 80% of total number of follicles) with features resembling jejunal Peyer's patch follicles, had lower number of apoptotic cells and reduced CA reactivity compared to the rest of the animals. The differences in CA reactivity in the follicle centres probably represent a variation in the presence of CA rich approximately 50 nm membrane-bounded particles known to be a feature of the sheep IPP. The present results suggest that the particles are involved in the modulation of the lymphocyte proliferation of the IPP follicles.  相似文献   
72.
This study aimed to determine the erythrocytic lipid peroxidation and haemoglobin oxidation as contributory factors causing anaemia in cattle (Friesian × Egyptian native breed) infected with Babesia bigemina. Blood was collected from 32 cows infected with B. bigemina along with 18 healthy cows as controls for determination of erythrocytic malondialdehyde (MDA), blood methaemoglobin (MetHb), plasma free haemoglobin (PHb), corpuscular osmotic fragility (COF), red blood cell count (RBC), total haemoglobin (Hb) and packed cell volume (PCV). Percentage of parasitaemia varied from 14% to 36%. MDA, MetHb, COF and PHb were significantly increased (P < 0.001) in infected cows versus controls. Parasitaemia was positively correlated (P < 0.001) with MDA, MetHb, COF and PHb. MDA was positively correlated (P < 0.001) with COF and PHb and negatively correlated (P < 0.001) with RBC, Hb and PCV. MetHb was negatively correlated (P < 0.001) with RBC, Hb and PCV and positively correlated (P < 0.001) with COF. In conclusion, B. bigemina infection in cattle is associated with a parasitic burden-dependent corpuscular oxidative damage as indicated by membrane lipid peroxidation and methaemoglobin formation, which are contributed to COF and intravascular haemolysis.  相似文献   
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74.
The aim of the present study was to determine the optimum dietary levels of soybean lecithin (SBL) for seabream (Sparus aurata) larvae, and its influence on production performance and digestive enzymes activity. Larvae were fed five formulated microdiets with five levels of SBL. Complete replacement of live preys with the experimental microdiets for seabream larvae at 16 dph produced over 55% survival rates, particularly in fish fed with the highest levels of SBL. Moreover, increase in dietary SBL up to 80 g kg−1 significantly improved larval growth, leading to high final total length and body weight. An increase in alkaline phosphatase activity with the elevation up to 80 g kg−1 SBL was also found denoting a better maturation of the digestive system. Besides, there was a stimulatory effect of dietary SBL on PLA2 activity. Finally, increasing dietary SBL lead to better utilization of dietary highly unsaturated fatty acid, as it was reflected in their higher content in both neutral and polar lipid of the larvae. In summary, elevation of dietary SBL up to 80 g kg−1 in microdiets for seabream significantly improved digestive enzymes activities, enterocyte maturation, utilization and deposition of dietary essential fatty acids and larval growth, as a consequence of a better digestion, absorption, transport and deposition of dietary nutrients.  相似文献   
75.
OBJECTIVE: To determine whether cross-reactivity exists between canine chromogranin A (CgA) and anti-human CgA antibody and investigate the usefulness of plasma CgA concentration measurements as an index of acute stress responses in dogs. ANIMALS: 12 healthy Beagles. PROCEDURE: Canine CgA was extracted and purified from canine adrenal glands of cadaver dogs for studying cross-reactivity with anti-human CgA antibody. Western blotting with anti-human CgA antibody was performed. Blood samples were collected from dogs at 0, 10, 20, 30, 40, 60, 120, and 180 minutes after IV administration of saline (0.9% NaCl) solution or insulin. Canine plasma CgA concentrations were determined by use of a CgA ELISA kit with rabbit antiserum against the carboxy-terminal fragment of human CgA. Plasma cortisol and catecholamine (ie, norepinephrine and epinephrine) concentrations were measured by use of an ELISA and a high-performance liquid chromatography method, respectively. RESULTS: Purified canine CgA was specifically detected by use of western blot analysis and an ELISA with anti-human CgA antibody. An increase in plasma CgA concentrations was observed in insulin-induced hypoglycemic dogs. Changes in plasma CgA concentration were correlated with changes in plasma cortisol or catecholamine concentrations of hypoglycemic dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Use of the CgA ELISA kit for determination of human plasma CgA concentrations is applicable to the measurement of canine plasma CgA concentrations. Canine plasma CgA concentrations, along with measurements of plasma cortisol and catecholamine concentrations, correctly reflect insulin-induced hypoglycemic stressed conditions in dogs. Measurement of canine plasma CgA concentrations may provide a useful index for evaluation of an acute stress response.  相似文献   
76.
ABSTRACT Cephalosporium maydis, the causal agent of late wilt of maize, was first described in Egypt in the 1960s, where it can cause yield losses of up to 40% in susceptible plantings. We characterized 866 isolates of C. maydis collected from 14 governates in Egypt, 7 in the Nile River Delta and 7 in southern (Middle and Upper) Egypt, with amplified fragment length polymorphism (AFLP) markers. The four AFLP primer-pair combinations generated 68 bands, 25 of which were polymorphic, resulting in 52 clonal haplotypes that clustered the 866 isolates into four phylogenetic lineages. Three lineages were found in both the Nile River Delta and southern Egypt. Lineage IV, the most diverse group (20 haplotypes), was recovered only from governates in the Nile River Delta. In some locations, one lineage dominated (up to 98% of the isolates recovered) and, from some fields, only a single haplotype was recovered. Under field conditions in Egypt, there is no evidence that C. maydis reproduces sexually. The nonuniform geographic distribution of the pathogen lineages within the country could be due to differences in climate or in the farming system, because host material differs in susceptibility and C. maydis lineages differ in pathogenicity.  相似文献   
77.
The objective of the present study was to compare the efficacy of a commercial limited-antigen diet (Eukanuba Veterinary Diets Response Formula FP/Canine, The Iams Company) with home-prepared diets in the diagnosis of adverse food reaction in dogs. The study was conducted in two phases. The first phase utilized 28 dogs fed a home-prepared diet to enable a diagnosis of adverse food reaction. Dogs diagnosed from this phase were entered into the second phase in which these dogs were fed the commercial limited-antigen diet. Owners of 10 of the 28 dogs quit Phase 1 before it could be completed, and one case was eliminated because extended treatment with steroids was required. Eight of the remaining 17 (47 %) dogs were diagnosed with an adverse food reaction. A reaction occurred in four of eight dogs fed the test diet in Phase 2. These results demonstrated the difficulties encountered by owners and veterinarians attempting to feed dogs home-prepared diets. In addition, the results of the study suggest that the occurrence of adverse reactions to fish could make it a less desirable ingredient as a limited antigenin canine diets.  相似文献   
78.
Oxidative stress is a general mechanism whereby free radicals induce oxidative damages and reduce the antioxidant defences of the biological systems. The aim of the present study was to determine plasma malondialdehyde levels as a biomarker of lipid peroxidation and its relation to the antioxidants status (plasma ascorbate and blood glutathione concentrations), liver function tests and anaemia in spontaneous ovine fascioliasis. For this purpose, jugular blood samples and livers of 27 infected ewes with Fasciola hepatica along with blood samples of 20 healthy (control) ewes were collected from animals slaughtered in a F. hepatica endemic area (Kharga oasis, Egypt). An increase (P<0.001) in plasma malondialdehyde (141.1%) accompanied by decreased levels (P<0.001) of albumin (29.3%) and ascorbate (36.2%) in plasma and glutathione in blood (31.6%) of infected sheep was noticed when compared with control values. In the infected group, malondialdehyde values were positively correlated with liver fluke burden (r=0.57, P=0.002) and the activity of plasma aspartate aminotransferase (r=0.39, P=0.0.046) and gamma-glutamyltransferase (r=0.64, P=0.0003) and negatively correlated with the concentrations of albumin (r=-0.53, P=0.004), ascorbate (r=-0.46, P=0.0.17) and glutathione (r=-0.41, P=0.034). In conclusion, oxidative stress is a significant feature of chronic F. hepatica infection in grazing sheep.  相似文献   
79.
Gnathonemuspetersii (F. Mormyridae) commonly known as Peters’ elephant-nose fish is a freshwater elephant fish native to West and Central African rivers. The present research aimed at metabolic profiling of its derived crude oil via GC-MS analysis. In addition, wound healing aptitude in adult male New Zealand Dutch strain albino rabbits along with isolated bioactive compounds in comparison with a commercial product (Mebo®). The molecular mechanism was studied through a number of in vitro investigations, i.e., radical scavenging and inhibition of COX enzymes, in addition to in silico molecular docking study. The results revealed a total of 35 identified (71.11%) compounds in the fish oil, belonging to fatty acids (59.57%), sterols (6.11%), and alkanes (5.43%). Phytochemical investigation of the crude oil afforded isolation of six compounds 1–6. Moreover, the crude oil showed significant in vitro hydrogen peroxide and superoxide radical scavenging activities. Furthermore, the crude oil along with one of its major components (compound 4) exhibited selective inhibitory activity towards COX-2 with IC50 values of 15.27 and 2.41 µM, respectively. Topical application of the crude oil on excision wounds showed a significant (p < 0.05) increase in the wound healing rate in comparison to the untreated and Mebo®-treated groups, where fish oil increased the TGF-β1 expression, down-regulated TNF-α, and IL-1β. Accordingly, Peters’ elephant-nose fish oil may be a potential alternative medication helping wound healing owing to its antioxidant and anti-inflammatory activities.  相似文献   
80.
Seedlings of sugar beet (Beta vulgaris) were grown in nutrient solutions containing a range of Cu and Zn concentrations. Based on measurements of shoot and root length and dry weight, copper was found to be already toxic at 10 μM, while Zn became toxic at 100 μM. At Cu and Zn levels found to induce a similar level of growth inhibiton, the influence of increasing the supply of K, Ca and Mg was investigated. Increasing the concentration of both Ca and Mg in the nutrient solution attenuated the degree of inhibition of root growth by Zn, but not Cu. Potassium did not affect the toxicity of either Cu or Zn. An increase in Ca decreased the level of both Cu and Zn in roots. Magnesium ameliorated the toxicity effects of Zn without effecting the Zn concentration in the roots. Treatment with Zn significantly decreased the concentration of Mg in the roots. An increased supply of Mg lowered the percentage decrease in root Mg concentration due to Zn toxicity. The maintenance of an adequate Mg level in the roots may be critical to prevent Zn induced inhibition of root growth.  相似文献   
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