首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   10篇
  免费   2篇
  5篇
水产渔业   3篇
畜牧兽医   2篇
植物保护   2篇
  2018年   2篇
  2016年   1篇
  2015年   1篇
  2013年   1篇
  2008年   2篇
  2005年   1篇
  2000年   1篇
  1998年   1篇
  1992年   2篇
排序方式: 共有12条查询结果,搜索用时 31 毫秒
1.
A virus, isolated from faba bean (Vicia faba) obtained from Algeria, was readily recognized as a tobravirus by its particle sizes and morphology. Pea (Pisum sativum) and French bean (Phaseolus vulgaris) characteristically reacted to the isolate like pea early-browning virus (PEBV), but faba bean,Antirrhinum majus, Nicotiana rustica, andN. tabacum reacted with line-pattern symptoms which were unusually brilliant on theNicotiana species. In electronmicroscope decoration tests, the isolate did not react with an antiserum to the Dutch type strain of PEBV, but with one to the broad bean yellow band (BBYB) serotype from Italy. It resembles this serotype in reaction on faba bean, but seems to differ appreciably onN. rustica, N. tabacum, andPetunia hybrida. It is described as a deviant isolate of the BBYB serotype of PEBV.All thirteen faba-bean genotypes tested were found to be susceptible to the Algerian isolate and two Dutch type strain isolates of the virus, and to react with erratic line-pattern symptoms to the Algerian isolate only. All ten genotypes of chickpea (Cicer arietinum) tested reacted hypersensitively, and four out of ten genotypes of lentil (Lens culinaris) were susceptible to the virus but reacted differentially to the three isolates. Seed transmission of PEBV, including the new isolate, in faba bean is confirmed (9% for the Algerian isolate, and over 45% for one of the Dutch type strain isolates), and seed transmission of the virus in a non-legume (N. rustica, 4%) is herewith first reported. This is the first report on the occurrence of the BBYB serotype of PEBV outside Italy, and of PEBV outside Morocco in North Africa.  相似文献   
2.
Most research works on the production frontier in aquaculture focus on efficiency measurement using either Stochastic Production Frontier (SPF) or Data Envelopment Analysis (DEA). The studies on productivity growth in aquaculture were limited, perhaps due to lack of time-series data. Nevertheless, total factor productivity analysis (TFP) in fish farms has started gaining popularity in recent years. In addition, the majority of the efficiency studies have centered on technical efficiency analysis but substantial increases in the output levels can be fully realized through improving overall economic efficiency. Therefore, this review suggests that future research should estimate all three efficiency indices (i.e., technical, allocative and economic efficiencies).  相似文献   
3.
A partial characterization of polyphenol oxidase (PPO) activity in Ocimum basilicum L. is described. PPO in O. basilicum L. was extracted and purified through (NH4)2SO4 precipitation, dialysis, and a Sepharose 4B-l-tyrosine-p-aminobenzoic acid affinity column. The samples obtained from (NH4)2SO4 precipitation and dialysis were used for the characterization of PPO. At the end of purification by affinity chromatography, 11.5-fold purification was achived. The purified enzyme exhibited a clear single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular mass of the enzyme was estimated to be approximately 54 kDa. The contents of total phenolic and protein of O. basilicum L. extracts were determined. The total phenolic content of O. basilicum L. was determined spectrophotometrically according to the Folin-Ciocalteu procedure and was found to be 280 mg 100 g(-1) on a fresh weight basis. The protein content was determined according to the Bradford method. The enzyme showed activity to 4-methylcatechol, catechol, and pyrogallol substrates, but not to tyrosine. Therefore, of these three substrates, 4-methylcatecol was the best substrate due to the highest V(max)/K(m) value, followed by pyrogallol and catechol. The optimum pH was at 6, 8, and 9 for 4-methylcatechol, catechol, and pyrogallol, respectively. The enzyme had an optimum temperature of 20, 40, and 50 degrees C for 4-methylcatechol, catechol, and pyrogallol, respectively. It was found that optimum temperature and pH were dependent on the substrates studied. The enzyme activity with increasing temperature and inactivation time for 4-methylcatechol, catechol, and pyrogallol substrates decreased due to heat denaturation of the enzyme.  相似文献   
4.
Information is key in reducing the uncertainties of sustainable agricultural practices (SAPs). The objective of this study was to improve the understanding of the relationship between utilized informational sources and other key identified factors affecting Malaysian vegetable producers' choices. The findings of a multivariate probit model suggest that information sources are complementary. The choices for these sources are influenced by heterogeneity in access to credit, social network (member of farmers association), and farm settings (distance from farm to market, resource depletion issues, and geographical regions). Future promotion of SAPs should be delivered through the provision of quality content disseminated through the preferred information sources, which target potential users.  相似文献   
5.
6.
A new strain of broad bean mottle virus, isolated from faba bean (Vicia faba L.) in the Sudan, is described. It differs considerably from known isolates by its nearly symptomless infection of faba bean in spite of high concentrations of the virus in infected plants. It does not differ from regular isolates in gel-diffusion serology, light and electron microscopy, host range and symptoms in major hosts other than faba bean. It may constitute a potential threat to other food legumes in the region.  相似文献   
7.
Tropical Animal Health and Production - The potential of using whole corn crop silage and rice straw as an alternative feed for the beef cattle based on the intake and growth performance were...  相似文献   
8.
Our objective was to evaluate kidney antioxidant status in rats subjected to an ultrasound examination. Thirty rats were divided into five groups for injection of saline (S) or anesthetic (A), and application of ultrasound using different modes, B mode, pulsed wave Doppler, and continuous wave Doppler, under anesthesia. Ultrasound was performed on days 1, 3, and 5 relative to the initiation of the experiment. Rats were then scarified on day 6. The kidney tissue thiobarbituric acid reactive substance (TBARS) level and superoxide dismutase (SOD) activity were measured. Both TBARS level and SOD activity increased, 21% and 38%, respectively, due to anesthesia (P < 0.04 for both). SOD activity increased further by a factor of 1.2 in response to ultrasound examination (P < 0.05), whereas TBARS level was not affected by Doppler and continuous wave Doppler compared to anesthesia. Increases in the level of TBARS (P < 0.03) and SOD activity (P < 0.01) were greatest when B-mode ultrasound was employed. These substances did not increase further when continuous wave Doppler was employed. The peak-negative acoustic pressure (9.16 vs. 9.74 MPa) and frequency (3.57 vs. 6.95 MHz) for B mode and pulsed wave Doppler were greater than those for continuous wave Doppler (0.22 MPa and 1.96 MHz). The estimated mechanical indexes were 4.87, 3.70, and 0.15 for B mode, pulsed wave Doppler, and continuous wave Doppler, respectively. In conclusion, anesthesia may cause tissue damage as reflected by elevated lipid peroxidation and free radical formation and ultrasound examination may amplify tissue damage through mechanical effects caused by ultrasound absorption.  相似文献   
9.
Adsorption of methylene blue from aqueous solutionsonto unexpanded and expanded perlite samples activatedby H2SO4 and NaCl solutions has beeninvestigated, to assess the possibility of usingperlite for removing cationic dyes from aqueoussolutions. The effects of pH and temperature of dyesolution on the adsorption capacities have beenevaluated. The experimental data were correlatedreasonably well by the Langmuir adsorption isothermand the isotherm parameters (Q m and K) have beencalculated. The removal efficiency (P) anddimensionless separation factor (R) have shown thatperlite can be used for removal of methylene blue fromaqueous solutions, but unexpanded perlite is more effective.  相似文献   
10.
Borax slime is formed during the production of borax from tincal, which is an important borate ore. It is a liquid containing the suspanded solid particles at high levels and is formed under the rich-in-borax solution in the reactor. This waste is discharged into the Marmara Sea and so causes environmental problems in Band?rma Golf. In this work, Borax production is aimed from the slime containing B2O3 at important levels. As a result it was found that B2O3 can be recovered and therefore the B2O3 pollution can be prevented by removing it from the waste.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号