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231.
Pharmacokinetic (PK)–pharmacodynamic (PD) integration of crystalline ceftiofur‐free acid (CCFA) was established in six healthy female goats administered subcutaneously (s.c.) on the left side of the neck at a dosage of 6.6 mg/kg body weight. Serum concentrations of ceftiofur and desfuroylceftiofur (DFC) were determined using high‐performance liquid chromatography. Mutant prevention concentration (MPC), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ceftiofur were determined for Pasteurella (P.) multocida. Mean terminal half‐life and mean residence time of ceftiofur + DFC were 48.6 h and 104 h, respectively. In vitro plasma protein binding of ceftiofur was 46.6% in goats. The MIC and MBC values of ceftiofur were similar in serum and MHB and a very small difference between these values confirmed bactericidal activity of drug against P. multocida. In vitro and ex vivo time–kill curves for P. multocida demonstrated a time‐dependent killing action of drug. Considering target serum concentration of 0.20 μg/mL, PK‐PD values for AUC24 h/MIC90 and T > MIC90, respectively, were 302 h and 192 h against P. multocida. A MPC/MIC ratio of 10–14 indicated that selective pressure for proliferation of resistant mutants of P. multocida is minimal after CCFA single‐dose administration. Based on MPC = 1.40 μg/mL for P. multocida, the PK‐PD indices, viz. T > MPC and AUC24/MPC, were 48 h and 43 h, respectively. The data suggested the use of single dose (6.6 mg/kg, s.c.) of CCFA in goats to obtain clinical and bacteriological cure of pneumonia due to P. multocida.  相似文献   
232.
Present study was conducted to assess the resource use efficiency of broilers production, in tunnel-ventilated environment control (ECBH) and open-sided conventional (OSCBH) house under different stocking densities. Different treatments comprised of T 0 (birds with floor space, 1.0/ft2/bird in open-sided conventional broiler house (OSCBH) as control, while different treatments in tunnel-ventilated environment control broiler house (ECBH) were T 1, T 2, T 3, T 4 and T 5 with floor space of 1.0, 0.9, 0.8, 0.7and 0.6 ft2 per bird, respectively. The results of shed microclimate indicated that shed temperature and temperature humidity index (THI) at 12:00 and 15:00 IST and maximum and minimum temperature in OSCBH were significantly (p ≤ 0.05) higher than ECBH. Litter moisture and pH did not differ significantly and were within permissible limits in both OSCBH and ECBH. Final body weight, body weight gain, feed intake were significantly higher and FCR, PER and EER were significantly better in ECBH than OSCBH (T 0) even at 10% increase in stocking density (T 2). Margin of receipt in T 2 in ECBH from sale of live bird/unit area and kilogram live weight per unit area was maximum which was Rs. 5.08/- and 3.56/- higher than T 0 for OSCBH.  相似文献   
233.
Hepatitis E virus (HEV) has two discrete epidemiological patterns: waterborne epidemics in developing countries only, caused by HEV genotype I, and sporadic zoonotic outbreaks in developing and developed countries caused by genotypes III and IV. This study was designed to investigate seroprevalence, molecular detection and the characterization of HEV by nested RT‐PCR in swine as well as the occupational risk to exposed human population in Punjab state of north‐western India. The occupational risk‐exposed group comprised of swine farmers (organized – mixed feed feeders and unorganized – swill feeders), slaughterhouse workers, sewage workers and veterinary internes. During the study period, blood and faecal samples were collected from 320 swine and 360 humans with both high and low occupational exposure risks. The overall seroprevalence of swine HEV was 65.00%, with a significantly higher seropositivity in growing pigs (2–8 months of age). The prevalence of HEV RNA in swine faecal samples by nRT‐PCR was 8.75% with a significantly higher detection in swill‐fed pigs. With humans in the high occupational exposure risk population, significantly higher anti‐HEV IgG seropositivity was observed (60.48%) as compared to control population (10.71%). Strong evidence of association between human anti‐HEV IgG seropositivity and certain occupational exposure risk groups was observed (< 0.05). This indicates that unorganized swine farmers, slaughterhouse workers and sewage workers have higher odds of HEV infection in this study region. Percentage of nucleotide similarity between swine and human HEV isolates was less than that found in countries with zoonotic HEV outbreaks. Molecular characterization revealed the circulation of G IV and G I genotypes among swine and human population in Punjab state, respectively.  相似文献   
234.
The intent of the experiments was to analyze impact of cadmium (Cd) and/or zinc (Zn) on membrane functionality, nutrient acquisition, antioxidant defense, and osmolyte accumulation in nodules of two pigeonpea (Cajanus cajan (L.) Millsp.) genotypes (Sel 85N and P792) with and without arbuscular mycorrhizal (AM) fungus Funneliformis mosseae. Findings demonstrated that accumulation of Cd and Zn in nodules resulted in membrane destabilization, nutrient imbalance, increased antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and glutathione reductase (GR)], and osmoprotectants such as total free amino acids (FAA), total soluble sugars (TSS), proline, and glycine betaine (GB). Cd had higher negative effects than Zn. P792 was comparatively more metal sensitive and displayed higher reductions than Sel 85N. Application of Zn decreased Cd uptake and reduced the phytotoxic effects of Cd. Zn1000 in combination with F. mosseae restored nodular membrane stability; enhanced nutrient pool [phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and iron (Fe)]; and boosted antioxidant enzyme activities and osmolyte synthesis in a genotype-dependent manner.  相似文献   
235.
Phosphate-solubilizing fungal strains were isolated from organically managed soil and tested for their ability to solubilize rock phosphate (RP), ferric phosphate and aluminium phosphate. These strains were identified as Aspergillus tubingensis and Aspergillus niger based on internal transcribed spacer sequence analysis. A field study was conducted in two different seasons in organically managed soil to test the efficacy of two strains, A. tubingensis (PSF-4) and A. niger (PSF-7) on the yield and soil fertility. RP was amended at the rate of 59 kg P2O5 ha?1 to study the effect of RP on soil fertility. The maize was grown in rainy season (July–October 2011) and wheat in winter season (November 2011–April 2012). Plant heights, shoot and root dry biomass and phosphorous (P) uptake in roots, shoots and grains were significantly increased due to inoculation in both crops. The yield of maize and wheat were significantly increased when inoculated along with RP fertilization. Organic carbon, P levels and soil enzyme activities were significantly increased due to inoculation. Results of present study suggested that A. tubingensis and A. niger improved the crop yield and soil fertility of organic farm when inoculated with RP fertilization.  相似文献   
236.
In vitro alterations induced by a 10 micrograms/ml and 50 micrograms/ml dose each of thiophenate and fenbendazole on the absorptive surfaces of Haemonchus contortus (Nematoda: Trichostrongylidae) were studied. The most significant changes were induced in the gut epithelium. Alkaline phosphatase and adenosine triphosphatase activities were decreased, succinic dehydrogenase activity was increased, while acid phosphatase and glucose-6-phosphatase were completely lost from the intestinal epithelium after treatment with either of the drugs. A stimulatory effect of these two anthelmintics was observe on lactic dehydrogenase and reduced nicotinamide adenine dinucleotide diaphorase distribution. Thiophenate caused an increase in the activities of glutamate dehydrogenase (GDH), glucose-6-phosphate dehydrogenase (G-6-PD) and nonspecific esterases and a decrease in reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-D) activity. Fenbendazole treatment led to the inhibition of GDH, while G-6-PD, NADPH-D, cytochrome oxidase, monoamine oxidase and nonspecific esterase activity remained unaltered in the epithelium.  相似文献   
237.
(1) The nitrogen-corrected apparent metabolisable energy (AME(N)) content of solvent-extracted rapeseed and sunflower seed (un-decorticated) meals in relation to species (chicken, guinea fowl and quail) and dietary addition of feed enzymes (0 or 0.5 g/kg diet) was evaluated by a diet replacement method in a 3 x 2 factorial design. (2) The metabolism trial was conducted at two substitution levels (200 and 400 g/kg diet) of each meal with or without supplementation of commercial enzyme preparation in 6 individuals or 6 groups of cockerels, guinea fowls and quails. (3) The experimental diets were fed for a period of 12 d followed by a 3-d collection period during which total feed consumed and droppings output were quantitatively recorded. (4) The AME(N) values of rapeseed meal for cockerels, guinea fowls and quails were 8.4, 8.7 and 8.8 MJ/kg, respectively, while the corresponding values for sunflower seed meal were 6.1, 6.1 and 6.2 MJ/kg dry matter, without enzyme supplementation. (5) The AME(N) value of rapeseed meal did not improve with enzyme supplementation. However, AME(N) values of sunflower seed meal significantly increased with enzyme supplementation, from 6.1 to 6.5 MJ/kg dry matter. (6) Since AME(N) values of rapeseed meal and sunflower seed meal were similar in chicken, guinea fowl and quail, values reported for chicken could, therefore, be used for guinea fowl and Japanese quail.  相似文献   
238.
The present studies were undertaken with a view to standardize the medium and culture conditions for embryo culture of five cultivars of walnut viz., ACO 38853, Netar Akhrot, Gobind, Solding Selection and Blackmore. Embryos from mature fruits were aseptically excised and cultured on MS medium supplemented with different combinations of BAP, kinetin and GA3. Best performing medium was MS with 0.5 mg l−1 kinetin, 0.5 mg l−1 BAP and 2 mg l−1 GA3 yielding 66.6% germination in Netar Akhrot after 12 days of culturing. Percent germination of excised embryos was higher when GA3 and cold treatments were simultaneously applied as compared to those when applied separately. Netar Akhrot was found to be the best responding cultivar, which had a range of 25–66.6% embryo germination under different culture conditions. Plantlets with shoots and roots have been obtained in Netar Akhrot and ACO38853 and are transferred to soil after hardening.  相似文献   
239.
Feces from 62 beavers (Castor canadensis) in Massachusetts were examined by fluorescence microscopy (IFA) and polymerase chain reaction (PCR) for Microsporidia species, Cryptosporidium spp., and Giardia spp. between January 2002 and December 2004. PCR-positive specimens were further examined by gene sequencing. Protist parasites were detected in 6.4% of the beavers. All were subadults and kits. Microsporidia species were not detected. Giardia spp. was detected by IFA from four beavers; Cryptosporidium spp. was also detected by IFA from two of these beavers. However, gene sequence data for the ssrRNA gene from these two Cryptosporidium spp.-positive beavers were inconclusive in identifying the species. Nucleotide sequences of the TPI, ssrRNA, and beta-giardin genes for Giardia spp. (deposited in GenBank) indicated that the four beavers were excreting Giardia duodenalis Assemblage B, the zoonotic genotype representing a potential source of waterborne Giardia spp. cysts.  相似文献   
240.
Genetic Resources and Crop Evolution - Assessment of genetic diversity and extent of trait variation among germplasm accessions facilitate the effective use of genetic resources for varietal...  相似文献   
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