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31.
Inhalt: Bei weiblichen Tieren der Rase Weiβes Alpenschaf (WAS) wurden die Einflüsse des Kontaktes mit einem Widder und der Frühjahrsschur (als Temperaturstress) als mögliche Impulse für die Aufhebung des saisonalen Anöstrus untersucht. Die Geschlechts-aktivität der Tiere wurde mittels des wöchentlich gemessenen Progesteron-Plasmaspiegels beurteilt. Ein vasektomierter Widder hielt bei den meisten Schafen der untersuchten
Gruppe die Geschlechtszyklen während des ganzen Jahres aufrecht; kein deutlicher Anostrus konnte beobachtet werden. Die Schur vor oder nach dem Weidebeginn ver-bunden mit einem Wechsel von schlechtem zu gutem Futter und mit einer Klimaänderung induzierte hingegen keine Unterbrechung des Anöstrus .
Contents: Reproductive cycles in White Alpine Sheep: effect of ram and shearing
The ability to interrupt the seasonal anestrus in the presence of a ram (pheromone effect) and after an early shearing (temperature stress) has been investigated on ewes of the race "white alpine sheep". The occurence of estrus was assessed by measuring of plasma progesterone in weekly intervals. No clear anestric period was observed in a group of 10 animals accompanied by a vasectomized ram throughout the whole year. The reproductive cycles of most ewes were regular (18 days). On the other hand, the shearing before or after the beginning of the grazing period that is accompanied by the change of a poor to a rich feed and by a change of climatic conditions, did not systematically influence the anestrus in our experiments . 相似文献
Gruppe die Geschlechtszyklen während des ganzen Jahres aufrecht; kein deutlicher Anostrus konnte beobachtet werden. Die Schur vor oder nach dem Weidebeginn ver-bunden mit einem Wechsel von schlechtem zu gutem Futter und mit einer Klimaänderung induzierte hingegen keine Unterbrechung des Anöstrus .
Contents: Reproductive cycles in White Alpine Sheep: effect of ram and shearing
The ability to interrupt the seasonal anestrus in the presence of a ram (pheromone effect) and after an early shearing (temperature stress) has been investigated on ewes of the race "white alpine sheep". The occurence of estrus was assessed by measuring of plasma progesterone in weekly intervals. No clear anestric period was observed in a group of 10 animals accompanied by a vasectomized ram throughout the whole year. The reproductive cycles of most ewes were regular (18 days). On the other hand, the shearing before or after the beginning of the grazing period that is accompanied by the change of a poor to a rich feed and by a change of climatic conditions, did not systematically influence the anestrus in our experiments . 相似文献
32.
ABSTRACT Late leaf spot (LLS), caused by Phaeoisariopsis personata, is a foliar disease of groundnut or peanut (Arachis hypogaea) with high economic and global importance. Antifungal and chitinolytic Bacillus circulans GRS 243 and Serratia marcescens GPS 5, selected among a collection of 393 peanut-associated bacteria, were applied as a prophylactic foliar spray and tested for control of LLS. Chitin-supplemented application of B. circulans GRS 243 and S. marcescens GPS 5 resulted in improved biological control of LLS disease. Supplementation of bacterial cells with 1% (wt/vol) colloidal chitin reduced lesion frequency by 60% compared with application of bacterial cells alone, in the greenhouse. Chitinsupplemented application of GRS 243 and GPS 5 also resulted in improved and stable control of LLS in a repeated field experiment and increased the pod yields by 62 and 75%, respectively, compared with the control. Chitin-supplemented application of GPS 5 was tested in six onfarm trials, and the increase in pod yields was up to 48% in kharif (rainy season). A 55-kDa chitinase was purified from the cell-free culture filtrate of GPS 5 by affinity chromatography and gel filtration. Purified chitinase of S. marcescens GPS 5 (specific activity 120 units) inhibited the in vitro germination of P. personata conidia, lysed the conidia, and effectively controlled LLS in greenhouse tests, indicating the importance of chitinolysis in biological control of LLS disease by GPS 5. 相似文献
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Rawther SS Saseendranath MR Nair GP Tresamol PV Pillai UN Abraham J Senthilkumar TM Nagalakshmy S Nimisha KK 《Tropical animal health and production》2012,44(4):911-914
In the present study efficacy of single intradermal Johnin test, acid fast staining of faecal smear and IS 900 faecal polymerase chain reaction tests was evaluated in 200 goats for detection of Mycobacterium avium subsp paratuberculosis. Two hundred goats comprising 150 goats from an organised farm in Trichur district and 50 goats reared under field condition
at farmers premise from Malappuram district of Kerala state formed the study population. Faecal smear from all the 200 goats
was stained by Ziehl–Neelsen acid fast stain and faecal polymerase chain reaction (PCR) specific for M. avium subsp paratuberculosis (MAP); IS 900 was performed on all samples. All the animals were subjected to single intradermal Johnin test. Out of 200 goats screened
for paratuberculosis, six goats (3%), 11 goats (5.5%) and 42 goats (21%) were found positive by Ziehl–Neelsen acid fast staining
of faecal smear, single intradermal Johnin test and IS 900 PCR respectively. Results of the present study indicate that amplification of IS 900 insertion element was the most specific and sensitive diagnostic detection method. Single intradermal Johnin test and Ziehl–Neelsen
acid fast staining did not show any significant difference. 相似文献
36.
37.
Bellaloui N Zablotowicz RM Reddy KN Abel CA 《Journal of agricultural and food chemistry》2008,56(8):2765-2772
Previous research has demonstrated that glyphosate can affect nitrogen fixation or nitrogen assimilation in soybean. This 2-year field study investigated the effects of glyphosate application of 1.12 and 3.36 kg of ae ha(-1) on nitrogen metabolism and seed composition in glyphosate-resistant (GR) soybean. There was no effect of glyphosate application on nitrogen fixation as measured by acetylene reduction assay, soybean yield, or seed nitrogen content. However, there were significant effects of glyphosate application on nitrogen assimilation, as measured by in vivo nitrate reductase activity (NRA) in leaves, roots, and nodules, especially at high rate. Transiently lower leaf nitrogen or (15)N natural abundance in high glyphosate application soybean supports the inhibition of NRA. With the higher glyphosate application level protein was significantly higher (10.3%) in treated soybean compared to untreated soybean. Inversely, total oil and linolenic acid were lowest at the high glyphosate application rate, but oleic acid was greatest (22%) in treated soybean. These results suggest that nitrate assimilation in GR soybean was more affected than nitrogen fixation by glyphosate application and that glyphosate application may alter nitrogen and carbon metabolism. 相似文献
38.
Electro-coagulation (EC) of a distillery spent wash has been optimized by Box–Behnken design of surface response analysis in terms of color removal. The design was employed to derive a statistical model for the effect of parameters studied on removal of color using iron anodes. The current density (31 mA/cm2), dilution (17.5%) and time of electrolysis (4 hours) had been found to be the optimum conditions for maximum 95% color removal. The actual color removal at optimized conditions was found to be 93.5% which confirms close to the predicted response using response surface methodology. 相似文献
39.
Tsai-Yu Lin Chen-Tuo Liao Hari K. Iyer 《Journal of Agricultural, Biological & Environmental Statistics》2008,13(2):221-241
Tolerance intervals are useful in practice to help determine limits for detection monitoring or assessment monitoring of factors that may impact the environment, ecological systems, or other biological processes. This article provides a procedure for construction of one-sided and two-sided tolerance intervals for a normally distributed random variable when the mean and variance of its distribution are estimated using data following an unbalanced one-way random effects model with covariates under heterogeneous error variances. The procedure developed here is based on the concept of a generalized pivotal quantity which has been frequently used to obtain confidence intervals in situations where conventional methods are difficult to apply or fail to provide s satisfactory solutions. For the one-sided case, the generalized pivotal quantity approach yields an exact solution. On the other hand, the method leads to good approximate intervals for the two-sided case. This is confirmed by a detailed simulation study, showing that the method may be recommended for practical use. Two real-data examples are given to illustrate the applicability of the proposed procedures. 相似文献
40.
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