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91.
92.
Ohne Zusammenfassung 相似文献
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L. O. Howard 《Journal of pest science》1926,2(9):114-118
Ohne Zusammenfassung 相似文献
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Genetic diversity of Pueraria lobata (kudzu) and closely related taxa as revealed by inter-simple sequence repeat analysis 总被引:4,自引:0,他引:4
Kudzu (Pueraria lobata) is a noxious weed infesting some areas of the USA. Knowledge of its genetic variation in both native and invasive areas can lead to effective biological control measures. Inter-simple sequence repeat (ISSR) variations were studied in P. lobata and its four closely related congeneric species (P. edulis, P. montana, P. phaseoloides and P. thomsoni). ISSR results allowed a clear separation of these five species. For P. lobata, 108 plants from China and USA were analysed. The samples from the US were genetically closer to Chinese P. lobata populations than to other congeneric populations. High genetic differentiation was found for P. lobata, P. montana and P. thomsoni in Chinese samples. High genetic diversity and low population differentiation was found in P. lobata samples of the US. This supports the hypothesis of multiple introductions into the USA from different sources in Japan or China, followed by subsequent gene exchange and recombination. 相似文献
99.
Y.Hu B. Tan K. Mai Q.Ai S.Zheng K. Cheng 《饲料与畜牧》2009,(4):52-55
导读:虾料配制时首先考虑的因子。
前言
凡纳滨对虾原产于美洲中南部的太平洋沿岸,我国于1988年引进,由于该虾生长快、适应性强、食性广、价格高、抗病力强等优点,迅速成为主要养殖品种。当前,饲料成本占总养殖成本的50~60%,而蛋白水平又是影响生长性能和饲料成本的主要因素。那么怎样才能降低饲料成本呢?通过优化蛋白能量和非蛋白能量在饲料中的比例,可以达到这一目的。如果蛋白相对于能量过量,那么, 相似文献
100.
ismail M 《Veterinary research communications》2007,31(4):467-476
The pharmacokinetics of difloxacin (Dicural) was studied in a crossover study using three groups (n = 4) of male and female Friesian calves after intravenous (i.v.), intramuscular (i.m.) and subcutaneous (s.c.) administrations
of 5 mg/kg body weight. Drug concentration in plasma was determined by high-performance liquid chromatography using fluorescence
detection. The plasma concentration–time data following i.v. administration were best fitted to a two-compartment open model
and those following i.m. and s.c. routes were best fitted using one-compartment open model. The collected data were subjected
to a computerized kinetic analysis. The mean i.v., i.m. and s.c. elimination half-lives (t
1/2β) were 5.56 ± 0.33 h, 6.12 ± 0.42 h and 7.26 ± 0.6 h, respectively. The steady-state volume of distribution (V
dss) was 1.12 ± 0.09 L/kg and total body clearance (ClB) was 2.19 ± 0.1 ml/(min. kg). The absorption half lives (t
1/2ab) were 0.38 ± 0.027 h and 2.1 ± 0.09 h, with systemic bioavailabilities (F) of 96.5% ± 6.4% and 84% ± 5.5% after i.m. and s.c. administration, respectively. After i.m. and s.c. dosing, peak plasma
concentrations (C
max) of 3.38 ± 0.13 μg/ml and 2.18 ± 0.12 μg/ml were attained after (t
max) 1.22 ± 0.20 h and 3.7 ± 0.52 h. The MIC90 of difloxacin for Mannheimia haemolytica was 0.29 ± 0.04 μg/ml. The AUC/MIC90 and C
max/MIC90 ratios for difloxacin following i.m. administration were 120 and 11.65, respectively and following s.c. administration were
97.58 and 7.51, respectively. Difloxacin was 31.7–36.8% bound to calf plasma protein. Since fluoroquinolones display concentration-dependent
activities, the doses of difloxacin used in this study are likely to involve better pharmacodynamic characteristics that are
associated with greater clinical efficacy following i.m. administration than following s.c. administration. 相似文献