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China and Hungary are major providers of the common carp (Cyprinus carpio L.) in East Asia and Europe respectively. However, the genetic variation and relationship of this species in the two countries have been poorly understood. In this study, mitochondrial COII‐tRNALys and D‐loop sequences were analysed to investigate the genetic structure and relationships of the representative wild and domesticated common carps distributed in China and Hungary. The results indicated that the genetic diversities of the Chinese common carps are higher than those of Hungarian common carps, and the diversities of the wild common carps are higher than those of domesticated common carps in both the countries. Analysis of molecular variance and pairwise FST demonstrated a significant genetic divergence between the Chinese and the Hungarian common carps, and between the wild and the domesticated common carps. Bayesian phylogenetic analysis and statistical parsimony network showed an obvious genetic differentiation between the Chinese and the Hungarian common carps, between the wild and the domesticated common carps. However, a few specimens and haplotypes from the Chinese wild common carps appeared in the Hungarian common carps, demonstrating that there was no absolutely isolated and possible genetic linker between the Chinese and the Hungarian common carps.  相似文献   
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 应用聚丙烯酰胺凝胶电泳,测定抗性不同的3个苹果品种过氧化物酶同工酶在接种褐斑病菌(Marssonina coronaria)后的变化规律。结果表明:苹果过氧化物酶同工酶在整个病程中呈类似常态曲线变化,症状出现时酶活性达最高峰,品种越感病,变化越强烈,表现在接种初期第12酶带增加早、增加量大;发病后期酶带数目比抗病品种减少更多。上述性状对病情诊断和幼苗抗性鉴定有参考价值。  相似文献   
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对中国柑桔上分离到的25个柑桔炭疽病菌分离系,进行酯酶同工酯及可溶性蛋白质的凝胶电泳。结果表明:病菌分离系的酯酶同工酶谱存在着差异,并且依据此差异划分出三个生理分化的类型;病菌分离系的可溶性蛋白质凝胶电泳的图谱,在其种内基本上保持一致,不能用可溶性蛋白质的凝胶电泳进行柑桔炭疽病菌生理分化的研究。  相似文献   
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Changes in gene regulation are thought to have contributed to the evolution of human development. However, in vivo evidence for uniquely human developmental regulatory function has remained elusive. In transgenic mice, a conserved noncoding sequence (HACNS1) that evolved extremely rapidly in humans acted as an enhancer of gene expression that has gained a strong limb expression domain relative to the orthologous elements from chimpanzee and rhesus macaque. This gain of function was consistent across two developmental stages in the mouse and included the presumptive anterior wrist and proximal thumb. In vivo analyses with synthetic enhancers, in which human-specific substitutions were introduced into the chimpanzee enhancer sequence or reverted in the human enhancer to the ancestral state, indicated that 13 substitutions clustered in an 81-base pair module otherwise highly constrained among terrestrial vertebrates were sufficient to confer the human-specific limb expression domain.  相似文献   
6.
Novel carbamic esters possessing a carbohydrate moiety derived from glycerol or D-glucose with two N,N-diethyldithiocarbamoyl groups and a series of bisdithiocarbamic esters having a ketone or an alkyl ester have been synthesized. The in vitro activity of these new compounds was evaluated against Fusarium oxysporum f. sp. lini. Some of the compounds [bis[1,3-S-(N,N-diethyldithiocarbamoyl)]-1, 3-dideoxyglycerol) and diethyl N,N'-(1,3-dideoxyglycer-1, 3-diyl)bis(dithiocarbamate)] were more active for inhibiting vegetative mycelium growth than, respectively, the commercial N, N-diethyldithiocarbamic acid sodium salt and Maneb. The structure activity of these new compounds is discussed.  相似文献   
7.
In experiments with calves during the milk-nutrition period we tested the use of the colonisation preparation Amylastim, containing a bacterial strain of Streptococcus bovis AO 24/85, as a factor speeding up the development of the rumen microflora. We gave the preparation to the animals for a period of four weeks and studied its influence on the microflora adherent to the epithelium of the rumen wall. We ascertained a significant increase in the number of Streptococcus bovis germs (P less than 0.001) as well as of alpha-amylase activity (P less than 0.05). When giving the preparation Amylastim to calves in large-scale production conditions we ascertained a positive effect on the health condition, total losses being lower.  相似文献   
8.
Very little information about NH4+ assimilation paths in rumen anaerobic bacteria is available, and the information about wild animals is completely missing. Glutamate dehydrogenase (GDH) isolated from the rumen strain B. ruminicola in fallow deer was purified and its properties were specified after crystalline ammonium sulphate precipitation and gel filtration on Sephadex G-200. The properties of partly purified GDH were specified. One of the first specifications concerning GDH from various sources was to determine its coenzyme specificity. The results of these determinations enabled to draw a general conclusion that GDH from non-animal sources was specific to only one coenzyme while GDH from animal sources could utilize the two coenzymes (Frieden, 1964). In our study the specificity of GDH isolated from the rumen strain B. ruminicola in fallow deer to the coenzyme NADH (Tab. I) was determined; this specificity was different from the coenzyme specificity of GDH isolated from the rumen strain B. ruminicola in calves where GDH was found to be specific to the coenzyme NADPH. The effect of increasing concentrations of NADH, 2-oxoglutarate and NH4+ on the enzyme reaction velocity was also investigated and Km was determined for NADH, 2-oxoglutarate and NH4+ (Tab. II). The kinetic properties of GDH isolated from different sources are considerably variable. Michaelis constants for GDH range from 0.003 to 0.125 mmol/dm3 for NADPH (NADH), from 0.95 to 7.4 mmol/dm3 for 2-oxoglutarate, and from 0.25 to 16 mmol/dm3 for NH4+ (Misono et al., 1985). The average value of Km for NH4+ in a mixed rumen population was 33 mmol/dm3 (Erfle et al., 1977).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Rat bite fever     
Rat bite fever (RBF) is a bacterial zoonosis for which two causal bacterial species have been identified: Streptobacillis moniliformis and Spirillum minus. Haverhill fever (HF) is a form of S. moniliformis infection believed to develop after ingestion of contaminated food or water.  相似文献   
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