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51.
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   
52.
文章采用野外植物样方采取及实验室数据分析相结合的方法,以阿巴嘎旗北部牧户常年放牧和隔年休牧的冬季草场为例,探讨短期休牧对克氏针茅草原植物物种多样性及群落稳定性的影响。结论如下:(1)两个草场植物群落内植物数量差异不大,主要差异表现在主要植物的平均重要值及两个草场仅有2对共优种。此外,短期休牧冬季草场的禾本科植物比重提升的同时,一年生藜科植物也显著提升;(2)短期休牧冬季草场的植物群落物种多样性指数略高于常年放牧冬季草场,但差异不显著;(3)两个草场植物群落处于中等相似水平,植物种间存在分异化趋势;(4)短期休牧冬季草场植物群落总体呈微弱正联结,种间联结松散,处于正向演替阶段,常年放牧冬季草场呈微弱负相关,群落较不稳定,存在一定退化风险;(5)两个草场的植物群落离稳定性都有一定差距,但短期休牧冬季草场植物群落稳定性略好于常年放牧冬季草场。可见,短期休牧有利于克氏针茅草原植物群落物种多样性和稳定性保持。  相似文献   
53.
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   
54.
Effects of small population size and reduced genetic variation on the viability of wild animal populations remain controversial. During a 35-year study of a remnant population of greater prairie chickens, population size decreased from 2000 individuals in 1962 to fewer than 50 by 1994. Concurrently, both fitness, as measured by fertility and hatching rates of eggs, and genetic diversity declined significantly. Conservation measures initiated in 1992 with translocations of birds from large, genetically diverse populations restored egg viability. Thus, sufficient genetic resources appear to be critical for maintaining populations of greater prairie chickens.  相似文献   
55.
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   
56.
The government of Kenya encourages aquaculture development by offering credit facilities through the government agricultural finance institution, Agriculture Finance Corporation. Nevertheless, the level of credit use in fish farming is very low. Access to credit is among several factors that affect farmers’ decision of whether to use particular technology or services. The study examined factors that affected the decision of fish farmers in Kenya to utilize credit facilities in fish production using a probit model. The analysis suggests that farmers in the Western province will have a 19% more probability of using credit facilities for their fish farming operations than farmers from the other provinces such as the Rift Valley, Central, and the Eastern province. The effect of tilapia sales on the probability of credit use by fish farmers is more than three times that of catfish sales. Total pond acreage owned by fish farmers had a positive effect on credit use but the effect was very small and negligible. The level of fish farmers’ use of credit facilities is very low, and there is probably the need to educate farmers on credit use and for the government agricultural lending agency and other commercial agricultural lenders to invest in this enterprise. Kenyan lending institutions have financed traditional agricultural enterprises, and with the growing production of farmed fish, more research is needed to document the aquaculture business model to assist in assessing the profitability potential in aquaculture.  相似文献   
57.
Micronutrient deficiencies in diets, including iron (Fe) and zinc (Zn), are an important public health problem across population in Ethiopia. Potato is a modest source of dietary nutrients. The purpose of this study was to assess the mineral (Fe & Zn) composition of potato germplasm in Ethiopia and grower's willingness to try new potato types. The Fe and Zn contents were assessed in peeled tubers of popular farmer varieties, and newly introduced Andean diploid group Phureja accessions and improved tetraploid clones grown in multi-location trials. Grower's preferences for the new potato types was assessed using a participatory approach. Significant variations in mineral and tuber yield traits exist among the germplasm assessed and broad-sense heritability appears to be high for most traits measured, suggesting that progress through breeding can be made among these materials. However, the slightly negative correlation of tuber yield with Fe and Zn content and user appreciation traits found in this study suggests that progress in improving crops for yield and enhanced Fe and Zn concentrations with end-user acceptable quality will be challenging. The results from this study provide baseline information on Fe and Zn composition of many popular farmer varieties in Ethiopia and end-user preference criteria for evaluating new potato varieties that would help to orient the biofortification breeding to the conditions and preference of farmers.  相似文献   
58.
短期玉米秸秆还田对冷凉地区土壤真菌多样性的影响   总被引:1,自引:0,他引:1  
在玉米吐丝期,利用传统涂布平板法和高通量测序技术,设置常规秸秆不还田(CK)、秸秆深翻还田(SF)和秸秆旋耕还田(XG)3个处理,研究0~10 cm、10~20 cm和20~30 cm土层真菌群落丰富度、多样性和群落结构变化,揭示冷凉地区玉米秸秆还田真菌群落结构及其差异。结果表明:冷凉地区玉米秸秆还田对土壤真菌多样性的影响较大,秸秆还田土壤中可培养真菌数为SFXGCK;秸秆还田后土壤真菌优势菌群发生变化,CK优势菌为马拉色氏霉菌属、被孢霉属和葡萄孢属,XG优势菌为被孢霉属;XG和SF表层土壤中耐冷酵母菌属和被孢霉属是优势菌;SF处理20~30 cm土层优势菌为葡萄孢属。真菌菌群Alpha多样性、群落组成丰度、RDA(Redundancy analysis)和菌群相似性综合分析可知,SF和XG 0~20 cm土层菌群差异小;SF和XG均能增加10~30 cm土层真菌群落丰度。  相似文献   
59.
研究了沙质草地与高平原草地六种牧草的总糖含量与还原糖含量变化情况.结果表明:沙质草地与高平原草地供试牧草的总糖含量变化(除糙隐子草外)和还原糖含量变化不同;除羊草和寸草苔外,其余几种牧草的还原糖含量都是高平原草地高于沙质草地.  相似文献   
60.
Objective   To describe the structure of the Australian poultry industry and discuss the potential for highly pathogenic avian influenza (HPAI) to spread between Australian poultry farms.
Procedure   High densities of poultry farms, frequent contacts between farms by service providers, the supply of live poultry markets (LPM) and the presence of free-range duck flocks in affected regions have been identified as risk factors for the spread of HPAI between flocks in outbreaks causing the death or destruction of over 1 million poultry overseas. Data on 1,594 commercial Australian chicken meat, chicken egg, duck and turkey farms were collected by a telephone questionnaire of farm managers to assess the risk of a HPAI outbreak in Australia.
Results and Discussion   Five regions of Australia had farm densities comparable to overseas regions that experienced widespread HPAI. Common service providers routinely contacted different classes and types of farms over wide geographic areas. However, no responding farms supplied LPM and the majority of duck farms did not produce free-range ducks.
Conclusion   Outbreaks of HPAI have the potential to cause serious impacts on the Australian poultry industry. The risk posted by LPM and free-range ducks is limited, but the movement of genetic stock and common service providers could spread infection between companies, industries or geographical regions. Biosecurity measures are therefore considered critical to limit the secondary spread of infection should an outbreak occur.  相似文献   
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