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排序方式: 共有635条查询结果,搜索用时 15 毫秒
1.
Post K 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(5):152-153
A four month old female toy Poodle showing multiple nodules 2 to 3 cm in diameter, some of which had ruptured over the neck and trunk area, was diagnosed as having nodular panniculitis. The animal had been treated with a course of chloramphenicol and ampicillin for one month with no response. The diagnosis was based on history, clinical signs, laboratory data and dramatic response to the addition of corticosteroid to the antibiotic therapy. 相似文献
2.
Effects of human chorionic gonadotrophin and castration on plasma gonadal steroid hormones of the dog 总被引:1,自引:1,他引:0 下载免费PDF全文
Post K 《The Canadian veterinary journal. La revue veterinaire canadienne》1982,23(3):98-101
An intramuscular injection of 500 I.U. of human chorionic gonadotrophin resulted in an increase of plasma testosterone and progesterone concentrations in the intact male dog, but had no effect on plasma 17B-estradiol concentration. Castration caused a rapid decrease in concentration of testosterone, progesterone, and 17B-estradiol, indicating that the tests were the major organs producing these hormones in the male dog. 相似文献
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Sherry Rachel Jacob MB Arunkumar Madhuban Gopal Chitra Srivastava SN Sinha 《Pest management science》2009,65(7):817-822
BACKGROUND: An efficient delivery system for seed‐protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film‐coat application in maintaining the persistence and potency of imidacloprid on Lycopersicon esculentum (L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages. RESULTS: High‐performance liquid chromatography (HPLC) revealed 0.135 mg kg?1 of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half‐dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide. CONCLUSION: Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry 相似文献
5.
Varwi Jacob Tavaziva Theo Verwijst 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(3):189-198
The aim of this study is to assess control effects of 2-methyl-4-chlorophenoxyacetic acid (MCPA) dosage, application timing and crop presence on the weed Cirsium arvense. Swedish farmers are recommended to control C. arvense chemically when most shoots are 10-20 cm tall, and mechanically at the compensation point (CP). Recent studies have shown that the CP occurs before shoots reach the three-leaf stage. We hypothesised that (i) herbicide application near the three-leaf stage gives the strongest control, (ii) crop presence increases herbicide effects, and (iii) a 50% herbicide dose gives the same effect as 100%. Treatments of the pot experiment consisted of MCPA 750; 0%, 50% and 100% of the recommended dose applied at leaf stages 3-8, with and without barley. The strongest control was obtained at four leaves and a maximum shoot height of 13 cm, using the recommended dose and with spring barley. In a field population, a maximum shoot height of 13 cm corresponded to a medium height of 6 cm. The 50% dose gave poorer control. Spraying with the recommended dose at the four-leaf stage reduced the development of C. arvense most effectively. Based on this, we recommend that herbicide spraying should be performed at earlier leaf stages/median heights than previously recommended. 相似文献
6.
国家森林防火指挥部赴黑龙江省检查组 《森林防火》2007,(4):8-9
根据国家森林防火指挥部领导的指示要求,国家林业局防火办组成了由国家森防指专家组成员、森林防火专业委员会主任朴东赫带队的秋防工作检查组,于2007年10月12日~19日赶赴黑龙江省,对当地秋季森林防火工作进行了检查调研。检查期间,工作组主要采取实地检查、抽查、座谈了解、听取汇报等方式,重点检查了哈尔滨、佳木斯、鹤岗三个地市辖区内的地方林业局、省森工总局林管局、 相似文献
7.
A silvopastoral agroforestry system involving sheep is an important silvicultural issue. We examined the factors that affect
the continuation or discontinuation of sheep vegetation management (SVM) in British Columbia. A questionnaire was used to
conduct interviews with a randomly selected sample of contractors and farmers who were involved in SVM in British Columbia
(BC). Based on a stepwise discriminant analysis, we found that the profitability of SVM, and the practitioners' commitment
(number of ewes owned by the farmer or contractor), experience (number of years the farmer or contractor has practiced SVM
on public lands in BC) and trust or confidence (number of years the farmer or contractor has consistently worked for the landlord)
contributed to the farmer's or contractor's continuation or discontinuation of SVM practice. The factors we defined seemed
to be validated (corroborated) by a complex of determinants voiced by various experts concerning the relationship between
SVM and the forestry economy in BC, the scale of sheep farming in BC, the relative absence of an agricultural infrastructure
to support sheep farming in BC, and the continuity of SVM from year to year. Further investigation into these factors and
others is required to advance our understanding of SVM in British Columbia.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
通过对澳大利亚维多利亚州森林大火相关情况的分析,结合我国森林防火特点,从国家和武警森林部队两个层面提出了加强森林防火工作的对策和措施. 相似文献
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10.
Grimm V Revilla E Berger U Jeltsch F Mooij WM Railsback SF Thulke HH Weiner J Wiegand T DeAngelis DL 《Science (New York, N.Y.)》2005,310(5750):987-991
Agent-based complex systems are dynamic networks of many interacting agents; examples include ecosystems, financial markets, and cities. The search for general principles underlying the internal organization of such systems often uses bottom-up simulation models such as cellular automata and agent-based models. No general framework for designing, testing, and analyzing bottom-up models has yet been established, but recent advances in ecological modeling have come together in a general strategy we call pattern-oriented modeling. This strategy provides a unifying framework for decoding the internal organization of agent-based complex systems and may lead toward unifying algorithmic theories of the relation between adaptive behavior and system complexity. 相似文献