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排序方式: 共有852条查询结果,搜索用时 15 毫秒
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Gary W. Ellison DVM MS Diplomate ACVS J. Brad Case DVM MS Diplomate ACVS‐SA Penny J. Regier DVM MS Diplomate ACVS‐SA 《Veterinary surgery : VS》2019,48(7):1171-1180
Intestinal wounds require precise closure after intestinal biopsy, enterotomy, or enterectomy in small animals. Preexisting factors such as intra‐abdominal sepsis and hypoalbuminemia as well as poor surgical technique increase the risk of intestinal dehiscence, with considerable negative impact on patient morbidity and mortality. Live dog studies have demonstrated the dangers of mucosal eversion especially in the septic abdomen. Approximating patterns preserve luminal diameter, heal optimally, and have equal bursting strength compared with inverting patterns after 24 hours. Simple interrupted and simple continuous suture patterns and disposable skin staples are established alternatives for manual wound closure. Knotless quilled suture currently used in laparoscopic gastropexy techniques shows bursting strength equal to monofilament sutures in dog cadaveric intestine. Dehiscence rates with hand sewn vs titanium automated stapling anastomosis are similar in uncomplicated cases; however, auto stapling devices may be the preferred method of anastomosis when preexisting abdominal sepsis is present and when patient size allows it. Regardless of the technique, current standard of care involves leak testing and omental wrapping, followed by early postoperative feeding. The past decade has ushered in an exciting new era of laparoscopic assisted techniques that have the potential to reduce postoperative pain and patient morbidity. An understanding of these applications will establish the future of minimally invasive small animal intestinal surgery for veterinary specialists. In summary, surgeons have a variety of methods at their disposal for optimal clinical outcome in small animal intestinal surgery. 相似文献
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Invited review: Role of livestock in human nutrition and health for poverty reduction in developing countries 总被引:3,自引:0,他引:3
Randolph TF Schelling E Grace D Nicholson CF Leroy JL Cole DC Demment MW Omore A Zinsstag J Ruel M 《Journal of animal science》2007,85(11):2788-2800
Livestock keeping is critical for many of the poor in the developing world, often contributing to multiple livelihood objectives and offering pathways out of poverty. Livestock keeping also affects an indispensable asset of the poor, their human capital, through its impact on their own nutrition and health. This paper outlines the linkages between livestock keeping and the physical well-being of the poor, and examines a number of commonly held beliefs that misrepresent livestock development issues related to these linkages. These beliefs limit the scope of intervention programs to promote livestock and limit their potential contribution to poverty reduction. Recognition of the complexity of the role livestock play in household decision-making and of the opportunities foregone due to these misconceptions can enhance the ability of livestock to contribute to human well-being in the developing world. 相似文献
115.
Amphiphilic poly(phenylquinoline)-block-polystyrene rod-coil diblock copolymers were observed to self-organize into robust, micrometer-scale, spherical, vesicular, cylindrical, and lamellar aggregates from solution. These diverse aggregate morphologies were seen at each composition, but their size scale decreased with a decreasing fraction of the rigid-rod block. Compared to coil-coil block copolymer micelles, the present aggregates are larger by about two orders of magnitude and have aggregation numbers of over 10(8). The spherical and cylindrical aggregates have large hollow cavities. Only spherical aggregates with aggregation numbers in excess of 10(9) were formed in the presence of fullerenes (C60, C70) in solution, resulting in the solubilization and encapsulation of over 10(10) fullerene molecules per aggregate. 相似文献
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针对四轴卧式镗床旋转轴需测几何误差的数目不统一与完备性缺失的问题,提出了基于形状创成函数的四轴卧式镗床旋转轴PIGEs形成机理分析方法与旋转轴完备几何误差测量辨识方法。基于形状创成机理构建了卧式镗床几何误差创成函数,确定了旋转轴可通过误差补偿进行调整的最少与位置无关的几何误差(Position-independent geometric error, PIGEs)数目。建立了卧式镗床旋转轴4项PIGEs、6项与位置有关的几何误差(Position-dependent geometric error, PDGEs)、6项安装误差(Setup error, SEs)与球杆仪(Double ball bar, DBB)测量轨迹半径之间的完备性函数模型,设计了基于DBB的四轴联动Viviani曲线测量轨迹,构建了旋转轴6项PDGEs的NURBS表征与PIGEs、SEs辨识方法。开展了误差补偿对比实验验证,结果表明,利用几何误差完备性测量与辨识结果进行误差补偿,较仅单一补偿6项PDGEs可提升圆轨迹测量精度40.69%。 相似文献
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Using light microscopy, polarizable amorphorous bodies with tinctorial characteristics of lipochromes and flocculent pigmental materials were found within the alveolar macrophages and peribronchiolar region of the lungs in a pig-tailed macaque (Macaca nemistrina) infected with simian lung mite (Pneumonyssus simicola). Examination of these pigmental bodies, using a high-voltage (1.2 meV) electron microscope and an energy-dispersive X-ray analysis system, indicated that the pigmental bodies contained a high concentration of silica. One female adult P simicola also was examined, and its digestive tract had visible, polarizable pigment and a high concentration of silica. Thus, lesions associated with lung mite infection in Old World monkeys may be superimposed by this silicotic condition, which may be associated with their arid, dusty, environment. Therefore, until the link between lung mite infection and silicosis is clarified, experimental inhalation toxicologic findings in mite-infected Old World monkeys should be interpreted cautiously. 相似文献
118.
Relationship of vulvar swelling to estrus in mink 总被引:1,自引:0,他引:1
119.
基于EDA技术的自动立木整枝机无线遥控接收系统 总被引:1,自引:0,他引:1
在分析自动立木整枝机工作过程和控制要求的基础上,该文详细阐述了自动立木整枝机无线遥控接收系统的组成及工作原理,进而采用电子设计自动化(EDA)技术设计了自动立木整枝机无线遥控接收系统的数字控制逻辑.通过优化CPLD内部逻辑电路,有效消除了逻辑竞争冒险.仿真结果表明,该系统控制可靠性较高,能有效提高自动立木整枝机的功能安全性. 相似文献
120.