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181.
Three varieties of Pea ( Pimm sativum L.) viz. EC33866 (early), P-116 (medium) and T-163 (late), differing in their flowering and maturity times, were taken for this study. The early variety recorded lower dry matter, CO2 exchange rate and lower yield. The harvest index (HI) was the highest (44 %) in this variety. Though medium and late varieties did not differ significantly in dry matter accumulation and pod yield, they differed in their HI. The HI in the medium variety is 42 % but in the late variety it is only 36%.
The late variety maintained high leaf area, leaf dry weight, high shoot/root, shoot/nodule and root/nodule ratios, increased nodule dry weight and maximum glycolate oxidase activity. But acetylene reduction activity was low, and the harvest index was lowest. On the other hand, in the early variety the dry matter accumulation was lowest but HI was highest. The major reasons for high HI in this variety were translocation of photosynthates to reproductive organs and lower photorespiration as indicated by low glycolate oxidase activity.  相似文献   
182.
Cold-adapted bioinoculants are considered as harbingers of sustainable hill agriculture. Therefore, two previously characterized psychrotolerant diazotrophs, Pseudomonas jesenii MP1 and Rhodococcus qingshengii S10107, were evaluated for their plant growthpromoting potential for chickpea (Cicer arietinum L.) grown under natural field conditions. Comparative analysis of agronomical and biochemical crop parameters revealed the irrelevance of chemical fertilizers for chickpea production; the diazotrophs alone were sufficient to fulfil the crop''s nutritional requirement. However, the integrated use of bacterial strains in combination with urea at 20 kg N ha-1 as urea was being recommended for higher crop yield and better soil nitrogen status. Quantitative polymerase chain reaction (qPCR) and denaturing gradient gel electrophoresis (DGGE)-based soil bacterial dynamics unveiled the persistence of both diazotrophs until the end of the crop maturation period without affecting the native micro-flora. Therefore, these bioinoculants can be explored as natural nitrogen resource, and an additional incentive in their bio-formulation will be a step towards agricultural sustainability.  相似文献   
183.
The acetyl bromide method has been modified to enable the rapid microscale determination of lignin content in Arabidopsis with the goal of determining the genes that control lignin in plants. Modifications include reduction in sample size, use of a microball mill, adoption of a modified rapid method of extraction, use of an ice-bath to stabilize solutions and reduction in the volume of solutions. The microscale method was shown to be rapid, accurate and precise with values in agreement with those determined by the full-scale acetyl bromide method. The extinction coefficient for Arabidopsis lignin, dissolved using acetyl bromide, was determined to be 23.35 g(-1) L cm(-1) at 280 nm. This value is independent of the Arabidopsis accession, environmental growth conditions and is insensitive to lignin structure. The newly developed method can be used to determine lignin content in the inflorescence stems of Arabidopsis for mapping of lignin-related genes.  相似文献   
184.
A feeding experiment was conducted in 40-L tanks each stocked with four fry of olive barb (2.05 ± 0.22 g). Dead notonectids (T1), live notonectids (T2), co-feeding of live notonectids and prepared diet (T3), prepared diet (T4), and plankton concentrate (T5) were fed ad libitum as the five treatments, each maintained with four replications. Proximate composition revealed higher protein and crude lipid contents in both notonectids and plankton concentrate compared to the prepared diet. The insect consumption rate was significantly higher with provision of dead insects (T1), followed by co-feeding of live insect and prepared diet (T3), and the live form (T2) (P < 0.05). Fry showed significantly higher final body weight and net weight gain, as well as specific growth rate, in co-fed group compared to those provided with live or dead insects. Growth performances decreased significantly when fed with prepared diet or plankton concentrate alone. While olive barb fry exhibited a preference for notonectids over the other diets, co-feeding appeared to offer a better nutritional profile for achieving higher growth. The study also indicated possibility of using olive barb as a good candidate for in situ biological control of notonectids during fingerling rearing of barbs and carps.  相似文献   
185.
Ganges River dolphins (Platanista gangetica spp. gangetica) are air-breathing, warm-blooded mammals endemic to the Ganges and Karnaphuli rivers of the Indian subcontinent. Nevertheless, very little basic histomorphological research has been conducted on this endangered species. Therefore, this study aimed to describe the morphological features of different organs of P. gangetica. Despite becoming aquatic animals, they showed similarities with terrestrial mammals, such as the pair of lungs and an apical bronchus in the respiratory system, which are pretty standard in ruminants and pigs. However, unlike the terrestrial animal, the tracheobronchial tree was stiffer due to circularly arranged anastomosing plates of the hyaline cartilaginous ring in the trachea, cartilaginous plates in the bronchiole, and thick alveolar septa. The digestive system showed a three-chambered mechanical and glandular stomach similar to the artiodactyles. However, the intestine showed smaller caecum like the monogastric mammal. The urogenital system showed lobulated kidneys, a urinary bladder, a fibroelastic penis with sigmoid flexure, and a long urethral process similar to some terrestrial ruminants. Considering the aquatic environment, all those modifications, unlike terrestrial mammals, are necessary for their adaptation. Thus, this research will broadly help our clinicians and conservationist to take further steps toward disease diagnosis and monitoring of marine health of this endangered species.  相似文献   
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Sprout damage which results in poor breadmaking quality due to enzymatic activity of α‐amylase is one of the important grading factors of wheat in Canada. Potential of near‐infrared (NIR) hyperspectral imaging was investigated to detect sprouting of wheat kernels. Artificially sprouted, midge‐damaged, and healthy wheat kernels were scanned using NIR hyperspectral imaging system in the range of 1000–1600 nm at 60 evenly distributed wavelengths. Multivariate image analysis (MVI) technique based on principal components analysis (PCA) was applied to reduce the dimensionality of the hyperspectral data. Three wavelengths 1101.7, 1132.2, and 1305.1 nm were identified as significant and used in analysis. Statistical discriminant classifiers (linear, quadratic, and Mahalanobis) were used to classify sprouted, midge‐damaged, and healthy wheat kernels. The discriminant classifiers gave maximum accuracy of 98.3 and 100% for classifying healthy and damaged kernels, respectively.  相似文献   
190.
Growth performance of kuria labeo, Labeo gonius as a component species in the major carp polyculture system was evaluated at two incorporation levels against a control without the species through a year‐round grow‐out study in nine earthen ponds (0.08 ha). Three species ratio of catla, silver carp, rohu, mrigal and kuria labeo at 15:15:40:30:0 (T‐1: control), 15:15:40:20:10 (T‐2) and 15:15:40:10:20 (T‐3) were evaluated as three treatments. The carps were stocked at a combined density of 7500 fingerlings ha?1. Silver carp demonstrated the highest survival (75–81%) followed by rohu (70–76%), catla (69–76%), kuria labeo (69–71%) and mrigal (67–69%). Species‐wise yield attributes such as survival, harvest weight, SGR and biomass yield of silver carp, catla and rohu were similar in their respective treatments. Kuria labeo at 10% inclusion demonstrated 12% higher harvest weight than its 20% inclusion. However, such higher weight gain could not affect the total biomass yields of carps which remained similar among the treatments. Furthermore, harvest weight of kuria labeo at 10% inclusion was comparable to that of mrigal when the latter incorporated at 20–30% level. Therefore, the study suggested 10% to be a suitable incorporation level for kuria labeo in the commercial grow‐out carp polyculture system.  相似文献   
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