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101.
Genetically modified (GM) crops expressing insect resistance and herbicide tolerance provide a novel approach for improved crop production but their advent at the same time presents serious challenges in terms of food safety. Although prevailing scientific proof has suggested that transgenic crops are analogous to their conventional counterparts, their use in human and animal diet gave rise to emotional public discussion. A number of studies had been conducted to evaluate the potential unintended effects of transgenic crops expressing single transgene, but very few studies for those with multiple transgenes. As the crops with single and multiple transgenes could impart different effects on non‐target organisms, thus, risk evaluation of transgenic crops expressing more than one transgene is required to declare their biosafety. The present study was therefore designed to assess the effects of different levels of dietary transgenic cottonseed expressing recombinants proteins produced by Cry1Ac, Cry2A and Cp4epsps genes on haematological indices of growing rabbits. A total of 48 rabbits were assigned to four dietary treatments containing different levels of transgenic cottonseeds (i.e., 0% w/w, 20% w/w, 30% w/w and 40% w/w) with 0% w/w serving as control. Haematological parameters were measured at periodic intervals (0, 45, 90, 135 and 180) days. No significant (p > 0.05) dose‐dependent effects were observed in most of the haematological parameters evaluated. Though, significant differences (p < 0.05) were recorded in the level of MCHC, MCH and HCT in some of experimental male and female rabbits, yet, they were not biologically significant, as all the differences were within the normal reference values. Our study suggested that feeding transgenic cottonseed of up to 40% could not adversely affect rabbit's haematological profile. However, further study needs to be conducted with different cotton genotypes expressing both single and polygenic traits before recommending the utilization of transgenic cottonseed in routine livestock feeding.  相似文献   
102.

Nitrogen efficiency of lactating buffalo can be increased by providing dietary crude protein (CP) precisely to the requirement. Twelve lactating Nili-Ravi buffaloes (6 primiparous and 6 multiparous) at 76?±?37.5 days in milk (DIM) were used in this study. The treatments were diets providing three levels of CP (% DM basis): (1) low-protein?=?11%; (2) medium-protein?=?13.1%; (3) high-protein?=?14.2% according to a 3?×?3 Latin square design. The period length of each treatment was 21 days and the total duration of experiment was 63 days. The diets were designed to provide similar energy. The nitrogen intake of buffalo increased linearly by increasing CP levels. Dry matter intake showed a tendency toward decrease in quadratic fashion, whereas milk yield decreased linearly in high-protein diet. No effect was observed on milk protein yield and content. Increasing the dietary CP levels increased plasma urea nitrogen, whereas glucose and triacylglycerol levels remain unaffected. Efficiency of dietary nitrogen utilization to milk averaged 21% and showed both linear and quadratic decreases by increasing the protein supply levels. In conclusion, low CP level showed higher milk production with low plasma urea nitrogen and high nitrogen efficiency in this experiment.

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103.
A multi‐enzyme mixture containing cellulases and hemicellulase activity, produced from Arachniotus sp., a white rot fungus, were applied on sunflower oil meal (SFOM) to degrade its fiber content. SFOM was treated with different concentrations of enzyme solution at variable pH, and incubated at temperatures ranging from 25 to 60°C, for different time periods ranging from 3 to 48 h to determine the maximum increase in metabolizable energy content by saccharification of fiber into sugars through enzymatic degradation. Maximum saccharification of SFOM fiber was obtained at a 1:1 enzyme substrate ratio, pH 4.0 and incubation for 36 h at 40°C. A reduction of 47.27% in crude fiber contents of sunflower oil meal was observed after enzyme treatment at optimized conditions. Enzyme treatment resulted in reduction of 41.53 and 31.87% in acid detergent fiber and neutral detergent fiber contents, respectively. An increase of 28.09% in nitrogen free extract contents of SFOM was found after enzyme treatment. True metabolizable energy contents of SFOM, after enzyme treatment, were increased from 1898.4 to 2314.9 kCal/kg.  相似文献   
104.
Poor quality of sandy loam soils ?is the main reason for low crop yield. Improvement of physicochemical properties of these soils is very challenging. Addition of organic sources may improve the soil properties. Therefore, this study investigated the adequacy of poultry-manure-compost (PMC) and pressmud-compost (PrMC) at 0 (control), 2, 4, 6, 8, and 10 t ha?1 for improving the physicochemical properties of sandy loam soil and maize performance. An increasing trend in most soil and crop traits was seen with increasing compost levels. For 10 t PMC ha?1, soil inorganic-N (512%), organic-carbon (78%), and water-holding capacity (65.36%) improved maximum. This resulted in the maximum mean crop growth rate (43.85%), stover yield (94%), grain protein (21%), and nitrogen use efficiency (30.6 kg kg?1). Contrarily, grain oil (?7%) was lowest at 10 t PMC ha?1. Consequently, 10 t PMC ha?1 could be much effective to improve the physicochemical properties of sandy loam soils and maize performance.  相似文献   
105.
The speed of toxic action of an insecticide is an indicator for control efficacy and has considerable practical importance. For agricultural pest control, fast-acting is an important feature for an insecticide to consistently reduce the amount of feeding damage. Butene-fipronil is a novel compound obtained via the structural modification of fipronil. However, information about the toxicity and speed of toxic action is still limited. In the present paper, we compared the toxic feature of butene-fipronil with seven other insecticides, of which imidacloprid and abamectin are slow-acting insecticides, and acephate, endosulfan, methomyl, α-cypermethrin and spinosad are fast-acting insecticides. We found that the contact and stomach toxicities of butene-fipronil were among the highest ever estimated to Leptinotarsa decemlineata and Drosophila melanogaster. The speed of toxic action of butene-fipronil was determined using median lethal time (LT50) at a dose (concentration) equivalent to LD80 values. For L. decemlineata, the values for butene-fipronil, imidacloprid, abamectin, acephate, endosulfan, methomyl, cypermethrin and spinosad were calculated to be 39.9, 36.5, 37.5, 20.2, 22.4, 23.8, 16.4 and 23.1 h, respectively. Those for D. melanogaster were 29.8, 31.5, 29.4, 14.0, 20.3, 18.1, 13.5, and 20.1 h, respectively. ANOVA analysis showed that butene-fipronil, imidacloprid, abamectin had similar LT50 values, whereas acephate, endosulfan, methomyl, spinosad and cypermethrin had comparable LT50 values. Thus, butene-fipronil belongs to slow-acting insecticides. Our results provide more empirical information for butene-fipronil potential application.  相似文献   
106.
Carps are the most diversified freshwater fish belonging to family Cyprinidae. Numerous probiotic and pathogenic lactic acid bacteria (LAB) have been characterized from carps. However, the diversity of these ecologically important bacteria is entirely unknown in freshwater fish of Pakistan. The present study aimed to characterize and identify the lactic acid bacteria from two carps viz. Laboe rohita and Cirrhinus mrigala and determine their antagonistic activity. Seventeen bacterial isolates were purified from the gastrointestinal tract and gills of these fish and characterized morphologically. Initially, seven isolates were screened as LAB using agar supplemented with CaCO3. Subsequently, only two isolates CILB2 and RIL10 were selected as LAB after high‐performance liquid chromatography analysis for lactic acid production. Isolates CILB2 and RIL10 were genetically identified as Enterococcus faecalis and Weissella sp., respectively after 16S rRNA gene sequence analysis. Both strains exhibited significant antagonistic activity against common fish pathogens Streptococcus agalactiae, Staphylococcus aureus and Escherichia coli. Enterococcus faecalis CILB2 and Weissella sp. RIL10 were also found negative for haemolysis and gelatinase activities and were sensitive to ampicillin, amoxicillin, doxycycline, erythromycin, chloramphenicol and co‐trimoxazole antibiotics. The identified LAB strains may further be investigated for their potential probiotic application in fish feed and food preservation techniques.  相似文献   
107.
Boron Application Improves Growth,Yield and Net Economic Return of Rice   总被引:1,自引:1,他引:0  
A field trial was conducted to evaluate the role of boron (B) application at different growth stages in improving the growth,yield and net economic return of rice at farmer’s fields during summer season,2009.Boron was soil applied (1.5 kg/hm2) at the transplanting,tillering,flowering and grain formation stages of rice;foliar applied (1.5% B solution) at the tillering,flowering and grain formation stages of rice,and dipped seedling roots in 1.5% B solution before transplanting;while control plots did not apply any B.Boron application (except dipping of seedling roots in B solution,which caused toxicity and reduced the number of tillers and straw yield than control) substantially improved the rice growth and yield.However,soil application was better in improving the number of grains per panicle,1000-grain weight,grain yield,harvest index,net economic income and ratio of benefit to cost compared with the rest of treatments.Overall,for improving rice performance and maximizing the net economic returns,B might be applied as soil application at flowering.  相似文献   
108.
Tissue samples were collected at random from cattle (Bos taurus) and buffalo (Bubalus bubalis) from an abattoir of the district of Lahore and were analyzed for the presence of Mycobacterium avium subsp. paratuberculosis and Mycobacterium bovis through acid-fast staining and polymerase chain reaction (PCR). Body condition of animals and diarrhea were recorded. Most of the animals were emaciated. Diarrhea was noticed in 15.6% of buffaloes and 19.2% of cattle. Intestinal pathology was observed in 29% of buffaloes and 32.8% of cattle. Number of mesenteric lymph node (MLN) showing gross lesions was a bit higher (35.6%) in cattle than buffalo (31.2%). Acid-fast staining of tissue scraping smears revealed the presence of acid-fast bacilli (AFB) in 17.4% intestinal and 16.4% MLN tissue samples in buffalo, while in cattle 19.2% intestinal and 17.8% MLN were found positive for AFB. In buffaloes, PCR confirmed 12.8% intestinal and 12.4% MLN positive samples for M. avium subsp. paratuberculosis. However, in cattle, PCR analysis demonstrated 14.2% positive results for M. avium subsp. paratuberculosis in both MLN and intestinal tissue samples. PCR also confirmed M. bovis in 5.8% of cattle and 5% of buffalo MLN and intestinal tissues. PCR positive tissue samples for M. avium subsp. paratuberculosis were from those animals which were emaciated, having diarrhea, and severe gross lesions. AFB were also detected in tissue scraping smears of these animals. It is concluded that infection by various mycobacterium species can be differentiated by PCR, which is not possible by acid-fast staining technique.  相似文献   
109.
110.
Ecosystems worldwide are rapidly losing taxonomic, phylogenetic, genetic, and functional diversity as a result of human appropriation of natural resources, modification of habitats and climate, and the spread of pathogenic, exotic, and domestic plants and animals. Twenty years of intense theoretical and empirical research have shown that such biotic impoverishment can markedly alter the biogeochemical and dynamic properties of ecosystems, but frontiers remain in linking this research to the complexity of wild nature, and in applying it to pressing environmental issues such as food, water, energy, and biosecurity. The question before us is whether these advances can take us beyond merely invoking the precautionary principle of conserving biodiversity to a predictive science that informs practical and specific solutions to mitigate and adapt to its loss.  相似文献   
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