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排序方式: 共有390条查询结果,搜索用时 15 毫秒
1.
1. An experiment on 1-week-old, White Leghorn female chicks was conducted to study the effect of aflatoxin AFB1 on weight gain, feed intake, feed gain ratio, age at sexual maturity, production and quality of eggs, retention of nutrients, pathoanatomical and histopathological parameters, and also on AFB1 residues in eggs and muscles of hens. The chicks were assigned to 4 dietary treatments: D1 (without AFB1), D2 (2.50 mg/kg AFB1), D3 (3.13 mg/kg AFB1), D4 (3.91 mg/kg AFB1) up to the age of 40 weeks. 2. At the end of the experiment, the mean body weight gain and feed intake were significantly lower in all aflatoxin-fed groups compared to control. The feed gain ratios were noted as 13.41, 13.59, 13.82 and 14.71, with the group fed the highest concentration of AFB1 showing a significantly poorer ratio than other groups. 3. Age at sexual maturity was also affected adversely by dietary AFB1: 193 d for D4 as compared to as early as 148 d for D1. Hen-d egg production was recorded as 96.92, 74.67, 65.98 and 50.75 in D1, D2, D3 and D4, respectively. 4. Average egg weights at the end of the experiment were 57.77, 57.49, 57.54 and 54.66 for D1, D2, D3 and D4, respectively. Shape index was significantly lower in D4 as compared to control. Contrary to this, albumen index was significantly higher in D4 as compared to D1. The values of yolk indices and eggshell thickness did not differ significantly among treatment groups. However, colour of yolk was reduced in all aflatoxin-fed groups compared to control. 5. Retentions of dry matter, crude protein, ether extract, calcium and metabolisable energy were adversely affected at various levels of AFB1 compared to control. 6. Pathoanatomical and histopathological studies showed various adverse changes in liver, kidney, heart, ovaries and bursa of Fabricius in AFB1-fed groups. 7. Different amounts of aflatoxin residues were detected in eggs and breast muscles of hen in all AFB1-fed groups. 相似文献
2.
Pooja A. R. Yogesh Pandey Meeti Punetha Anju Kala Hari Abdul Samad Gyanendra Singh Vikrant Singh Chouhan 《Reproduction in domestic animals》2023,58(1):60-72
The aim of the present study was to evaluate the expression and localization of lymphangiogenic factors (VEGF-C and VEGF-D), their receptor (VEGFR3) and lymphatic endothelial marker (LYVE1) in buffalo placenta during early pregnancy [EP], and to investigate the functional role of lymphangiogenic growth factors in placental lymphangiogenesis. The mRNA and protein expression of VEGF-C, VEGF-D, their receptor VEGFR3 and LYVE1 showed significant expression in EP1 (29–42 days) and EP2 stages (51–82 days) both in caruncle (maternal part) and cotyledon (foetal part) of the buffalo placenta. Immunoreactivity of VEGF-C, VEGF-D and LYVE1 was observed around the endometrial gland, in lymphatics and trophoblast cells, whereas VEGFR3 mainly localized in lymphatics of the caruncle and cotyledons. Cultured trophoblast cells were treated with VEGF-C/VEGF-D (50, 100 and 150 ng/ml) and combined doses of VEGF-C and VEGF-D (150 ng/ml) each for different time durations (24, 48 and 72 h). The mRNA expression of LYVE1 and PCNA was significantly (p < .001) upregulated with VEGF-C and VEGF-D and combined treatment (@150 ng/ml), as well as significantly downregulating Caspase-3 at 48 and 72 h. Thus, the present study provides evidence that lymphangiogenic factors are expressed in buffalo placental compartments and they may play a significant role in the regulation of placental function in water buffaloes. 相似文献
3.
Sabyasachi Banerjee Seema Singh Shailesh Pandey Maneesh S. Bhandari Amit Pandey Krishna Giri 《Forest Pathology》2020,50(2)
Wilt disease caused by Fusarium solani is a serious constraint to Dalbergia sissoo (shisham) plantations in northern India. In this study, the antagonistic potential of 40 bacterial isolates recovered from rhizophere soil of healthy shisham trees, and a well‐characterized Trichoderma species (Trichoderma virens) were tested for their possibility as biocontrol agents for F. solani. Two promising isolates (S1 and S15) were identified which inhibited pathogen growth, caused chitin degradation, produced siderophores and solubilized phosphate in vitro. Isolate S15 scored highest for hydrogen cyanide (HCN) production while isolate S1 was a non‐HCN producer. These two isolates were identified as Serratia marcescens (S1) and Pseudomonas azotoformans (S15) following sequence analysis of 16S rDNA. In dual culture assays, T. virens caused 80% inhibition of mycelial growth of the test fungus. The three selected antagonists when tested in planta in the glasshouse completely suppressed production of wilt symptoms on 12‐month‐old shisham plants. Further work is needed to ascertain the potential of these isolates to be used as biocontrol agents to manage shisham wilt under field conditions. 相似文献
4.
Bindraban Prem S. Dimkpa Christian O. Pandey Renu 《Biology and Fertility of Soils》2020,56(3):299-317
Biology and Fertility of Soils - Mineral phosphorus (P) fertilizers support high crop yields and contribute to feeding the teeming global population. However, complex edaphic processes cause P to... 相似文献
5.
Proyuth Ly Quynh Duong Vu Lars Stoumann Jensen Arjun Pandey Andreas de Neergaard 《Paddy and Water Environment》2015,13(4):465-475
We studied the effects of water regimes and nutrient amendments on CH4 and N2O emissions in a 2 × 3 factorial, completely randomised growth chamber experiment. Treatments included continuously flooded (CF) and alternate wetting and drying (AWD), and three organic amendments: no amendment-control, rice straw (RS) and biochar (BC). Compound fertiliser was applied to all treatments. Rice was grown in columns packed with a paddy soil from Cambodia. Results revealed faster mineralisation of organic carbon (RS and BC) when applied in water-saturated conditions lasting for 2 weeks instead of flooding. This resulted in lower total CH4 emissions in treatments under AWD than those under the CF water regime, namely 44 % in RS treatments and 29 % in BC treatments. Nitrous oxide fluxes were generally non-detectable during the experimental period except after fertilisation events, and the total N2O–N emissions accounted for on average 1.7 % of the total applied mineral fertiliser N. Overall, the global warming potentials (GWPs) were lower in treatments under AWD than those under the CF water regime except for the control treatment with only mineral fertiliser application. Grain yields were slightly higher in treatments under AWD than the CF water regime. Hence, the yield-scaled GWP was also lower in the treatments under the AWD water regime, namely 51 % in RS, 59 % in BC and 17 % in control treatments. Control treatments had the lowest GWP, but provided the highest yield. The yield-scaled GWP under these treatments was therefore lower than under the other treatments. 相似文献
6.
Ratnaboli Bose Shailesh Pandey Pooja Joshi Sabyasachi Banerjee Amit Pandey Maneesh S. Bhandari 《Forest Pathology》2021,51(1):e12658
Eucalyptus spp. and their hybrids are frequently cloned and mass planted across farmland tracts and commercial plantations in northern India. It is a viable feeder species to the paper and pulp industries in this region. In 2018 and 2019, during field surveys conducted in northern India, a serious leaf blight disease was frequently observed in E. tereticornis plantations. Isolation from the blighted leaf samples consistently yielded fungal isolates having Calonectria‐like morphology. Morphological features coupled with sequence analysis of partial β‐tubulin (TUB2) and partial translation elongation factor‐alpha (TEF1) gene regions of two fungal isolates confirmed the species as Ca. cerciana. In detached leaf assays and glasshouse inoculation experiments, both isolates produced symptoms similar to those observed on the naturally infected leaves. Koch's postulates were fulfilled by re‐isolating Ca. cerciana from the inoculated leaves. This work is the first to confirm that Ca. cerciana is associated with a serious leaf blight disease of Eucalyptus in northern India and is an important addition to the taxonomy of Calonectria fungi in India. 相似文献
7.
Agroforestry trees are now well known to play a central role in the build up of nutrients pools and their transformations
similar to that of forest ecosystem, however, information on the potential of homegarden trees accumulating and releasing
nitrogen (mineralization) is lacking. The present study reports seasonal variations in pool sizes of mineral N (NH4+-N and NO3−-N), and net N-mineralization rate in relation to rainfall and temperature under coconut (Cocos nucifera L.), clove (Eugenia caryophyllata Thunb) and nutmeg (Myristica fragrans Houtt. Nees) trees in a coconut-spice trees plantation for two annual cycles in the equatorial humid climate of South Andaman
Island of India. Concentration of NH4+-N was the highest during wet season (May–October) and the lowest during post-wet season (November–January) under all the
tree species. On the contrary, concentration of NO3−-N was the lowest in the wet season and the highest during the post-wet season. However, concentrations of the mineral N were
the highest under the nutmeg and the lowest under the coconut trees. Like the pool sizes, mean annual mineralization was the
highest under the nutmeg (561 mg kg−1 yr−1) and the lowest under the coconut trees (393 mg kg−1 yr−1). Rate of mineralization was the highest during the post-wet season and the lowest during the dry season (February–April)
under all the tree species. High rainfall during the wet season, however, reduced the rate of nitrification under all the
tree species. The mean annual mineralization was logarithmically related with rainfall amount and mean monthly temperature. 相似文献
8.
Akash Tariq Kaiwen Pan Olusanya Abiodun Olatunji Corina Graciano Ningning Li Zilong Li Dagang Song Feng Sun Meta Francis Justine Dan Huang Shanxing Gong Bikram Pandey Muhammad Idrees Mohammed A. Dakhil 《植物养料与土壤学杂志》2019,182(4):586-596
Drought is one of the major environmental stresses altering forest productivity. However, nutrient availability can modulate drought resistance. Phoebe zhennan (gold Phoebe) is a high‐quality timber‐producing but threatened tree species in China, facing serious anthropogenic disturbances and abiotic constraints that restrict its growth and development. However, little attention has been given to designing adaptive strategies for its management by evaluating the possible role of major nutrients, particularly nitrogen (N), on its morphological and physio‐biochemical responses under water stress. To evaluate these responses, a complete randomized design was followed to investigate the effects of two irrigation levels (well‐watered and drought‐stressed conditions) and N fertilization treatments (with and without N). Drought stress significantly affected the growth of seedlings, as indicated by impaired photosynthesis, pigment degradation, disrupted N metabolism, over‐production of reactive oxygen species and enhanced lipid peroxidation. Nitrogen supplementation under drought stress had remarkable positive effects on the growth through physio‐biochemical adjustments as shown by higher level of nitrogenous compounds and up‐regulation of N‐associated metabolic enzymes activities which might be due to N‐mediated improved leaf relative water contents and photosynthetic efficiency. In addition, N application reduced oxidative stress and membrane damage, and maintained a high accumulation of osmolytes. However, in well‐watered seedlings N fertilization significantly improved root biomass and net CO2 assimilation rate suggesting high N‐use efficiency of the seedlings. These findings reveal that drought significantly affects the growth of P. zhennan, while N fertilization plays a crucial role in alleviating water stress damage by improving its drought tolerance potential at low metabolic costs. Therefore, N fertilization could be considered as an effective strategy for the conservation and management of P. zhennan in the face of future climate change. 相似文献
9.
10.
Avinash?Pandey I.?S.?BishtEmail author K.?V.?Bhat P.?S.?Mehta 《Genetic Resources and Crop Evolution》2011,58(8):1213-1224
Role of informal seed system in landrace diversification, in situ conservation on-farm and sustainability in production were investigated as a case study for rice diversity in Indian Himalayas.
The diachronic pattern of landrace occurrence revealed substantial increase, both in landrace number and frequency, in time.
The local level seed supply in Uttarakhand Himalaya revealed that about 96% seed supply originated from informal system and
a mere 4% seed supply is met from formal seed supply networks. In higher elevation ranges, beyond 1200 masl, largely landrace
cultivation is practiced and a greater landrace diversification in traditional production was observed. Substantial variations
due to environmental adaptations in niche habitats help provide important donor germplasm for crop improvement to users. Further,
the population genetic structure also indicated enough diversity being maintained on-farm. Developing pathways for strengthening
local level seed system for landrace diversification linked to sustainability in food production and conserving agro-biodiversity
has been emphasized. 相似文献