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排序方式: 共有110条查询结果,搜索用时 31 毫秒
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This case report describes the accidental intramuscular administration of 20 mL Gudair® vaccine to a 7‐year‐old Standardbred mare and successful treatment of the resulting inflammatory reaction by radical surgical resection. 相似文献
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Lunar surface magnetic fields and their interaction with the solar wind: results from lunar prospector 总被引:1,自引:0,他引:1
RP Lin DL Mitchell DW Curtis KA Anderson CW Carlson J McFadden MH Acuna LL Hood A Binder 《Science (New York, N.Y.)》1998,281(5382):1480-1484
The magnetometer and electron reflectometer experiment on the Lunar Prospector spacecraft has obtained maps of lunar crustal magnetic fields and observed the interaction between the solar wind and regions of strong crustal magnetic fields at high selenographic latitude (30 degreesS to 80 degreesS) and low ( approximately 100 kilometers) altitude. Electron reflection maps of the regions antipodal to the Imbrium and Serenitatis impact basins, extending to 80 degreesS latitude, show that crustal magnetic fields fill most of the antipodal zones of those basins. This finding provides further evidence for the hypothesis that basin-forming impacts result in magnetization of the lunar crust at their antipodes. The crustal magnetic fields of the Imbrium antipode region are strong enough to deflect the solar wind and form a miniature (100 to several hundred kilometers across) magnetosphere, magnetosheath, and bow shock system. 相似文献
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田间试验系统地比较了新冬20/沈玉2002不同套种模式(“522模式”与“952模式”)及“521模式”下保麦10号/蠡玉35、保麦10号/登海3672、新冬20/蠡玉35的产量、叶面积指数、光合势及干物质积累等性状的差异。结果表明,“522模式”新冬20/沈玉2002周年产量(17 838.2 kg·hm-2)较“952模式”(16 550.9 kg·hm-2)增产7.8%,其中,冬小麦增产18.4%。“521模式”保麦10号/蠡玉35、保麦10号/登海3672、新冬20/蠡玉35周年产量为19 905.0~20 751.0 kg·hm-2,其中,冬小麦产量为9 740~10 275 kg·hm-2、夏玉米产量为9 630~10 211.0 kg·hm-2;冬小麦孕穗期和开花期叶面积指数分别为6.0、5.0左右,返青至成熟的总光合势290.2~324.3×104·m2·d·hm-2;夏玉米生育期111 d,大喇叭口期至吐丝后20 d的叶面积指数均保持在4左右,生育期间总光合势233.1~257.5×104·m2·d·hm-2,冬小麦和玉米总光合势为523.3~581.8×104·m2·d·hm-2;总干物质量38 569.1~40 487.0 kg·hm-2;冬小麦产量的边际效应为85.7%~112.9%。“521模式”比“952模式”大幅度增产,是小麦行数和边行数及边际产量增大的结果,并将夏玉米播期提至麦收前15 d左右,延长玉米生育期(达110 d左右),优化株行配置使玉米增产显著,实现全年超高产。“521模式”同时充分利用了冬小麦边际补偿效应和玉米时间补偿效应,较“952模式”易获得周年超高产。并对超高产栽培技术进行了讨论。 相似文献
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Biosecurity risks are a major threat to the profitability of the industry as well as impacting human and animal health. Livestock producers play a crucial role in biosecurity as the first to notice changes in the health or productivity of their stock and are generally responsible for implementing protective measures. However, uptake of biosecurity measures by producers is variable. We critically appraised the current literature regarding biosecurity practices in Australian livestock industries and highlight aspects that are well understood as well as those where further research or information is needed. Findings from 12 cross-sectional studies suggest that Australian producers' knowledge of biosecurity methods and importance might have a positive influence on their willingness to implement or incorporate biosecurity practices. There is moderate evidence supportive of biosecurity being well understood by livestock producers across Australia. Barriers to producers using biosecurity practices included lack of information or communication from agricultural, veterinary or government organisations. It was found that larger stock numbers were positively correlated with biosecurity implementation and that producers used veterinarians, government and industry agencies as resources for trusted information. 相似文献
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KA Hewson GF Browning JM Devlin J Ignjatovic AH Noormohammadi 《Australian veterinary journal》2010,88(10):408-413
Objective A real-time polymerase chain reaction (PCR)/high-resolution melt (HRM) curve analysis protocol was developed in our laboratory to differentiate infectious bronchitis (IB) virus reference strains. In the current study, this method was used to detect and classify IB viruses in field submissions. Procedure Over an 11-month period samples from 40 cases of suspected IB virus were received and 17 submissions were positive for IB virus by polymerase chain reaction. HRM curve analysis classified each strain as subgroup 1, 2 or 3 strain (12 submissions) or a strain that was unable to be classified (5 submissions). The 3′ untranslated region (UTR) and partial S1 gene nucleotide sequences for the 17 IB virus strains were determined and their identity with those of the relative reference strains compared to confirm the classifications generated using the HRM curve analysis. Results Of the 12 IB field viruses classified as subgroup 1, 2, or 3 using HRM curve analysis, the 3′UTR and S1 gene nucleotide sequences had identities ≥99% with the respective subgroup reference strain. Analysis of the 3′ UTR and S1 gene nucleotide sequences for the five IB virus strains that could not be classified indicated that four belonged to one of the subgroups, and one was a potential recombinant strain (between strains from subgroups 2 and 3). A novel recombinant strain was also detected. Conclusion HRM curve analysis can rapidly assign the majority of IB viruses present in field submissions to known subgroups. Importantly, HRM curve analysis also identified variant genotypes that require further investigation. 相似文献
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Cost-benefit evaluation of artificial insemination for genetic improvement of wool-producing sheep 总被引:1,自引:0,他引:1
KA ABBOTT 《Australian veterinary journal》1994,71(11):353-360
SUMMARY The financial costs and benefits associated with the use of artificial insemination (AI) in commercial flocks are evaluated. Benefits are calculated in terms of net present values after summing the discounted value of benefits over 20 years. Two breeding strategies are evaluated. With the first, AI is used to produce flock ewes and wethers. The method is unlikely to be profitable unless high breeding value rams are available for AI programs with fresh semen. With the second, AI is used to produce home-bred rams, which in turn sire flock ewes and wethers. This approach is more likely to be profitable. The cost of AI per lamb weaned from laparoscopic AI programs is about $100. Benefits exceed this cost for rams of very high merit when wool prices are moderate or higher. Flock structure has a significant effect on the benefits. Flocks with low wether retention rates have benefits half that of flocks that retain most wethers to 6 years of age. AI with purchased semen also provides benefits to risk management for owners of commercial flocks who wish to breed their own replacement flock rams. 相似文献
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