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931.
The present study evaluates the use of rubber seed meal (RSM) and its defatted product on the growth and feeding performance of common carp Cyprinus carpio L. Digestibility test using chromium oxide as a tracer showed that defatted RSM (DRSM) resulted in significantly higher total feed, protein, Ca and P digestibility than those of unprocessed RSM (URSM). Growth test was performed with a control and three experimental diets which were 50% DRSM (50% of protein originated from DRSM), 75% DRSM (75% of protein originated from DRSM) and 50% URSM (50% protein originated from URSM). The use of diet containing URSM to replace 50% protein source resulted in the lowest growth and feeding performance which might correlate to the high cyanide content (1.16%) in the diet. Furthermore, providing the fish with this particular experimental diet also caused decline in fish haematological parameters and increased abnormalities in the fish intestine and kidney. Overall results suggested that the use of defatted RSM to replace 50% of other protein sources resulted in a comparable growth and feeding performance of common carp juvenile without any adverse effect.  相似文献   
932.
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   
933.
Journal of Plant Diseases and Protection - Fifteen Pakistan’s indigenous medicinal plant extracts were investigated for various secondary metabolites and their potential against tomato early...  相似文献   
934.
This study was conducted to monitor the biodegradation of alpha-, beta-, gamma-, and delta-hexachlorocyclohexane (HCH) isomers in liquid culture by a Pandoraea species and determine the influence of pH and temperature on the biodegradation of alpha- and gamma-HCH in liquid as well as in soil slurry cultures. The Pandoraea species degraded 79.4% delta-HCH and 34.3% gamma-HCH in liquid culture at 4 weeks of incubation. alpha- and beta-HCH exhibited almost identical rates (41.6 and 42.4%, respectively) of degradation. The highest degradation of alpha- and gamma-HCH (67.1 and 60.2%, respectively) was observed at an initial pH of 8.0 in liquid; 58.4 and 51.7% rates of degradation of alpha- and gamma-HCH, respectively, at an initial pH of 9.0 were found in soil slurry cultures. An incubation temperature of 30 degrees C was optimum for effective degradation of alpha- and gamma-HCH isomers (62.5 and 57.7%, respectively) in liquid culture, and 54.3 and 51.9% rates of degradation of alpha- and gamma-HCH isomers, respectively, were found in a soil slurry. Increasing the soil/water ratio decreased the extent of degradation of both HCH isomers. Degradation of HCH isomers occurred concomitant with bacterial growth. Byproducts of growth from Pandoraea species significantly decreased the pH of the liquid and the soil slurry during the growth on HCH isomers. The results of this study suggest that this bacterial strain may effectively be used for remediating polluted sites and water contaminated with different HCH isomers over a range of environmental conditions.  相似文献   
935.
936.
A pot experiment was conducted in sandy clay loam saline-sodic soil to assess the effects of farm yard manure (FYM), municipal solid waste (MSW) composts and gypsum application on nitrate leaching, soil chemical properties and crop productivity under rice-wheat cropping system. It also aims at establishing the correlation between soil phsico-chemical properties and yield response using principle component analysis and Pearson correlation analysis. The MSW was decomposed aerobically, an-aerobically and co-composted. Maximum nitrate leaching was observed during rice (75.9 mg L?1) and wheat (37.2 mg L?1) with an-aerobically decomposed MSW as compared with control treatment. Results revealed a decrease in soil pH (?6.95% and ?8.77%), electrical conductivity (EC) (?48.13% and ?51.04%), calcium carbonate (CaCO3) (?40.30% and ?48.96%), and sodium adsorption ratio (SAR) (?40.27% and ?45.98%) with an-aerobically decomposed MSW compost during rice and wheat, respectively. In this treatment, organic matter (OM) (93.55% and 121.51%) and cation exchange capacity (CEC) (19.31% and 31.79%) were the highest as compared with control treatment during rice and wheat, respectively. Rice and wheat growth were significantly (p≤ 0.05) increased by an-aerobically decomposed MSW followed by co-compost, aerobically decomposed MSW, FYM, gypsum and control. Furthermore, Pearson correlation coefficients predicted significant positive correlation of yield with soil OM, and CEC while inverse relationship was observed with EC, pH, CaCO3, and nitrogen use efficiency. Soil amelioration with organic and gypsum amendments was further confirmed with principal component analysis. This study has proved an-aerobically decomposed MSW as an effective solution for MSW disposal, thereby improving soil chemical properties and crop productivity from sandy clay loam saline-sodic soil.  相似文献   
937.
[目的]研究不同降雨强度和坡度对紫色土坡面产流过程的影响,为紫色土区域的水土流失防治提供科学依据。[方法]基于室内人工模拟降雨试验开展研究。[结果]不同雨强和坡度下的产流过程可大致分为"下凹"型和"上凸"型,且分别可以用指数函数和对数函数描述。随着雨强和坡度的增大,产流时间逐渐减小,产流过程逐渐趋于一致,坡面径流量逐渐增加。坡度和雨强对径流总量的贡献率有着对比消长的关系,小雨强下(雨强为33和54mm/h),坡度是坡面径流总量的主要贡献因子,随着雨强增大(雨强为94和125mm/h),雨强为坡面径流总量的主要贡献因子。[结论]坡度和雨强均为坡面侵蚀的主要影响因子,随着坡度和雨强的增加,坡面侵蚀更加剧烈,主要侵蚀因子也由坡度转变为雨强。  相似文献   
938.
The present research was conducted to explore the impact of alternative organic amendments on physicochemical properties of soil and their critical value for kiwi seedlings growth. The experiment was laid out in completely randomized design with 3 replications and 20 seedlings per replication. The highest pH (8.0) was recorded in T3 (compost + silt) and the highest electrical conductivity (EC) of 5.91 dS/m, organic matter (24.11%), organic carbon (13.99%), organic nitrogen (1.51%) were recorded in T8 (compost + peat moss (PM) + leaf manure) and the highest soil porosity (SP) (45.95%) and lowest bulk density (0.67) were recorded in T4 (PM + garden soil (GS)). EC higher than 1.99 and SP (45.95%) were found critical and adversely affected seedling survival. The highest plant height (103 and 93 cm), number of leaves (23 and 20), number of first-order lateral roots (NFLRM) (9 and 8.5), whole seedling fresh mass (75 and 72 g), fresh root mass (FRM) (35 and 35 g), shoot fresh mass (46 and 40 g), root collar diameter (RCD) (13 and 12 mm), and shoot diameter (10 and 9 mm) were recorded in T5 (compost + GS) and T7 (compost + PM + GS). Strong and positive correlations were observed among NFLRP, RFM, and RCD (R2 = 0.89 and 0.96) and all the above-ground seedling traits (R2 = 0.86–0.98). It is concluded that compost is a good soil amendment for producing good quality graftable kiwi seedlings and evaluation of seedling root system architecture could be used to predict the potential and success of seedlings in the field.  相似文献   
939.
The information of soil compaction effects on growth and yield of crops for saline and waterlogged soils is scanty. A pot experiment was conducted on a sandy clay loam soil during 2001–2002 to study the interactive effects of soil compaction, salinity and waterlogging on grain yield and yield components of two wheat (Triticum aestivum) genotypes (Aqaab and MH-97). Compaction was achieved at 10% moisture level by dropping 5 kg weight, controlled by a tripod stand for 20 times from 0.6 m height on a wooden block placed inside the soil filled pots. Soil bulk density of non-compact and compact treatments was measured as 1.21 and 1.65 Mg m−3, respectively. The desired salinity level (15 dS m−1) was developed by mixing the required amount of NaCl in soil before filling the pots. Waterlogging was developed by flooding the pots for 21 days both at tillering and booting stages. Compaction aggravated the adverse effect of salinity on grain yield and different yield components of both the wheat genotypes. Average reduction in grain yield was 44% under non-compact saline conditions against 76% under compact saline conditions. Similarly, the reduction was about 20% more for 100 grain weight and shoot length, 30% more for number of spikelets per spike, 37% more for number of tillers per plant, and 32% more for straw weight in compact saline treatment than in non-compact saline treatment. Compaction alone caused a reduction of 36% in grain yield. The effect of waterlogging on grain yield and yield components was mostly not changed significantly due to compaction. Rather waterlogging mitigated the effect of compaction for most of the yield components except for number of spikes per plant. Therefore, as for normal soils, the cultivation of salt-affected soils should employ implements and techniques which minimize compaction of root zone soil. The effect of soil compaction can also be minimized by light irrigations with short intervals and by using a stress tolerant crop genotype.  相似文献   
940.
This review highlights the underexplored potential and promises of marine bioactive peptides (MBPs) with unique structural, physicochemical, and biological activities to fight against the current and future human pathologies. A particular focus is given to the marine environment as a significant source to obtain or extract high-value MBPs from touched/untouched sources. For instance, marine microorganisms, including microalgae, bacteria, fungi, and marine polysaccharides, are considered prolific sources of amino acids at large, and peptides/polypeptides in particular, with fundamental structural sequence and functional entities of a carboxyl group, amine, hydrogen, and a variety of R groups. Thus, MBPs with tunable features, both structural and functional entities, along with bioactive traits of clinical and therapeutic value, are of ultimate interest to reinforce biomedical settings in the 21st century. On the other front, as the largest biome globally, the marine biome is the so-called “epitome of untouched or underexploited natural resources” and a considerable source with significant potentialities. Therefore, considering their biological and biomedical importance, researchers around the globe are redirecting and/or regaining their interests in valorizing the marine biome-based MBPs. This review focuses on the widespread bioactivities of MBPs, FDA-approved MBPs in the market, sustainable development goals (SDGs), and legislation to valorize marine biome to underlying the impact role of bioactive elements with the related pathways. Finally, a detailed overview of current challenges, conclusions, and future perspectives is also given to satisfy the stimulating demands of the pharmaceutical sector of the modern world.  相似文献   
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