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41.
Cryptosporidium parvum (C. parvum) is the causal agent of cryptosporidiosis in many animals, mainly cattle, and possesses a high zoonotic potential. It occurs worldwide and ubiquitously. Detection of C. parvum is mainly performed directly but purification of the oocysts is useful to increase sensitivity and to obtain oocyst material for further use. The study was designed to compare (a) three different direct diagnostic methods, namely modified Ziehl-Neelsen staining, carbol fuchsin staining and conventional PCR, and (b) three routine oocyst purification methods, in particular flotation with saturated sodium chloride solution, Sheather's sucrose solution and a Percoll(?) gradient. During comparison of purification methods, special regard was paid to the ability to separate morphologically intact oocysts from the morphologically degenerated fraction or viable from non-viable oocysts, respectively. Results: (a) Diagnostic methods: Most effective in C. parvum oocysts detection in calf faeces was PCR; carbol fuchsin and modified Ziehl-Neelsen stainings achieved comparable results. (b) Purification methods: Oocyst flotation using sodium chloride solution showed to be superior to Percoll(?) gradient centrifugation and sugar flotation in terms of purification quality, recovery efficacy (yield) and reduction of the proportion of degenerated or non-viable oocysts. 相似文献
42.
The purpose of this prospective, double-blinded, placebo-controlled clinical trial was to investigate the efficacy of topical eprinomectin for the treatment of psoroptic mange infestation in horses. 24 privately owned hunter/jumper and dressage horses were diagnosed with psoroptic mange infestation based on physical findings and skin scraping results were enrolled and randomly assigned to either topical eprinomectin pour-on solution (at a dose of 500mug/kg body weight weekly once for four applications) treatment group or a placebo group (purified water). Clinical evaluations and skin scrapings were done by the same veterinary investigator at the beginning, during and at the end of the treatment. Both owners and veterinary investigator were blinded to the allocation to the groups. The efficacy of eprinomectin was assessed both clinically and parasitologically by the presence or absence of viable mites. Horses were scraped for psoroptic mites on days 7, 14, 21, 28 and 40 for follow-up. Fisher's exact test was used to assess differences between the eprinomectin treatment and placebo in the number of horses without mites (cure rates) on each assessment date. It was found that significantly fewer eprinomectin treated horses had P. equi mites detected on skin scrapings (p<0.01) than the placebo group. In conclusion, eprinomectin was effective and safe therapy against natural infestations of P. equi in the horses included in this study. 相似文献
43.
Eastern India receives higher average annual rainfall (1000–2000 mm) but 80% of it occurs within the June–September (rainy season), whereas the winter season (November–March) is dry. Due to a shortage of soil moisture, most rainfed areas of the region remain fallow during the winter season and cultivation (mainly rice) is confined to the rainy season only (June–September). To explore the possibility of double cropping in the rainfed rice areas, three oilseed crops, viz., linseed (Linum usitatissimum L.), safflower (Carthamous tinctorious L.), mustard (Brassica juncea L.), were grown in a representative rainfed area of eastern India, i.e. Dhenkanal, Orissa, during the dry/winter season by applying irrigation water at phonological stages. Study revealed that with three supplemental irrigations, the highest WUE was achieved by safflower followed by linseed with the mean values being 3.04 and 2.59 kg ha−1 mm−1, respectively. Whereas, with one irrigation, the highest water use efficiency (WUE) was achieved for safflower (1.23 kg ha−1 mm−1) followed by linseed (0.93 kg ha−1 mm−1). Of the three crops studied, safflower withdrew maximum water followed by mustard and crops were shown to use 90–105 mm more water than linseed. With three irrigations, average maximum rooting depths were 1.66, 1.17 and 0.67 m for safflower, mustard and linseed, respectively, which were 13.5, 10.6 and 11.4% higher than for single irrigated crops because of more wet sub soils and decrease of soil strength. The crop growth parameters like leaf area, dry biomass were also recorded with different levels of irrigation. The research work amply revealed the potential of growing these low water requiring oilseed crops in rice fallow during dry/winter season utilizing limited irrigation from harvested rainwater of rainy season. Crop coefficients (Kc) of three winter season oilseed crops were derived using field water balance approach. Study showed that LAI was significantly correlated with Kc values with the R2 values of 0.91, 0.89 and 0.94 in linseed, safflower and mustard, respectively. When LAI exceeded 3.0, the Kc value was 1 in safflower and mustard whereas in linseed corresponding LAI was 2.5. Study revealed that the Kc values for the development and mid season stage were slightly higher to that obtained by the procedure proposed by FAO, which might be due to local advection. 相似文献
44.
Karaer Z Guven E Akcay A Kar S Nalbantoglu S Cakmak A 《Tropical animal health and production》2012,44(3):589-594
The presence of Eimeria spp. oocysts in fecal samples collected from 1,108 broiler houses in six regions, representing about 12% of all broiler farms
in Turkey, was studied using the modified McMaster method. The age of the chickens in the 1,108 pens varied from 1 to 50 days.
Oocysts were found in 602 (54.3%) of these broiler houses, and the mean OPG (oocysts per gram of feces) in those samples was
36,498.7 (50–952,000). No indication of clinical coccidiosis or other clinically evident infection or wide mortality was encountered
in any of the pens studied. Further study showed that the age of the chickens, the occurrence of diarrhea on the houses and
the density of broiler breeding in the area correlated with subclinical coccidiosis prevalence. 相似文献
45.
K. Vijayan A. Tikader P. K. Kar P. P. Srivastava A. K. Awasthi K. Thangavelu B. Saratchandra 《Genetic Resources and Crop Evolution》2006,53(5):873-882
In order to formulate appropriate strategies for the conservation and utilization of the wild mulberry genetic resources available
in India, a study was undertaken with 20 mulberry genotypes from the four different species. Seventeen intersimple sequence
repeat primers were used to generate a total of 114 markers, of which 98 (85.96%) were polymorphic. Seven unique bands for
Morus serrata Roxb. and one for both M. serrata Roxb. and Morus macroura Miq. were identified, of which one fragment has been sequenced and deposited in the EMBL-GeneBank (AJ-585512). The genetic
dissimilarity coefficients varied from 0.078 to 0.530 among these genotypes and from 0.168 to 0.465 among the species. The
dendrograms realized from these markers clustered the genotypes into three groups. The outermost group was M. serrata Roxb., which was followed by the group of M. macroura Miq. and the innermost group contained genotypes of Morus indica L. and Morus alba L. This intermixing of genotypes of M. indica and M. alba supports the view that M. indica is merely a synonym of M. alba. Distribution of the genotypes on a two-dimensional figure upon multidimensional scaling with ALSCAL program, further, confirmed
the genetic divergence between the cultivated and wild mulberry groups. On the basis of the results a few potential wild mulberry
genotypes were identified for its conservation and utilization in breeding programs to confer the stress tolerance to the
cultivated varieties of mulberry. 相似文献
46.
Gouranga Kar Ashwani Kumar B. Chandrabhaskar 《Archives of Agronomy and Soil Science》2013,59(8):847-857
The effects of organic manure supplementation on rice–pulse cropping system productivity were studied. Three pulses, viz., blackgram, greengram and pea were grown after rice on the same plots to explore the feasibility of growing second crops with carry-over residual soil moisture and residual soil fertility. The study revealed that during the rainy season, 30%–35% higher rice grain yield was obtained when both inorganic and organic sources of nutrients were applied compared with the full dose of inorganic fertilizer, and the rice grain yield was 65%–78% higher than obtained following farmers’ practices. In the post-rainy season, pea crop recorded the highest grain yield of 490 kg ha-1 under the treatment combination of Sesbania and inorganic fertilizer. Organic carbon, and available N, P, K also enhanced yield by 20%–29%, 5.0%–29.4% to 7.9%–39.9% and 22.4%–60.3%, respectively when 25% N was applied through different organic sources of nutrients (green manure/press mud/farmyard manure). 相似文献
47.
K. Vijayan P. K. Kar A. Tikader P. P. Srivastava A. K. Awasthi K. Thangavelu B. Saratchandra 《Plant Breeding》2004,123(6):568-572
Sixteen populations of the wild mulberry, Morus serrata Roxb., were analysed for their genetic diversity with the aim of using them in introgressive breeding programmes with cultivated relatives. Five genets from each population were collected from different natural populations of M. serrata present in Uttaranchal and Himachal Pradesh in India, and diversity of morpho‐anatomical traits and inter‐simple sequence repeat (ISSR) markers were studied. Significant amounts of genetic diversity were observed among these populations for morpho‐anatomical as well as DNA markers. The 17 ISSR primers generated a total of 95 DNA markers, 51 of which were polymorphic, revealing 67% polymorphism among the populations. The pair‐wise genetic distance, estimated from these DNA markers varied from 0.091 between Urgam‐3 and Kathpuria to 0.258 between Dakrakao‐1 and Dunda with an average genetic distance of 0.165. Clustering analysis grouped these 16 populations into three broad groups. The grouping showed a moderate correlation with the geographical distances. Based on the morphological traits and molecular genetic variability, plants of Urgam‐1, Bhowali farm, Nainitikar, Dunda or Korwa‐2 can be selected for breeding and conservation programmes. 相似文献
48.
Stigmasterol, isolated from the bark of Butea monosperma was evaluated for its thyroid hormone and glucose regulatory efficacy in mice. Its administration at 2.6 mg/kg/d for 20 days reduced serum triiodothyronine (T3), thyroxin (T4) and glucose concentrations as well as the activity of hepatic glucose-6-phophatase (G-6-Pase) with a concomitant increase in insulin indicating its thyroid inhibiting and hypoglycemic properties. A decrease in the hepatic lipid peroxidation (LPO) and an increase in the activities of catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) suggested its antioxidative potential. The highest concentration tested (5.2 mg/kg) evoked pro-oxidative activity. 相似文献
49.
Abstract. Field experiments were carried out to evaluate the relative efficacy of organic manures in improving the productivity and pest tolerance of rice growing in a lateritic soil. The effects of three commercial manures: processed city waste (PCW), vermicompost (VC) and oil cake pellets (OCP), were assessed in comparison to farmyard manure (FYM) and inorganic fertilizer all at the same total N applied. Of the organic manures tested, FYM produced the maximum straw and grain yields. Differences in yield among the organic manure treatments were mainly attributed to variation in the amounts of available N, P, K and micronutrients. Effect of manures on soil physical condition was not studied. The uptake of N, P and K by rice plants with FYM was significantly greater than all other commercial manures and inorganic fertilizer. The tolerance of rice plants to attack by pathogens and pests, measured in terms of grain yield was highest in the treatment with FYM. Among the commercial manures PCW showed the greatest promise and emerged as a potential alternative to FYM. 相似文献
50.
Shea butter has been extracted from the seeds of the shea tree,B. parkii, with various organic solvents. Petroleum ether (40°–60°C),n-hexane, chloroform, and benzene extracted 32%–38% of fat and 8–9 mg% of vitamin E. These solvents, particularly petroleum ether andn-hexane, can be used for the production of shea butter that is free from any oxidized fat and coloring impurities. 相似文献