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41.
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   
42.
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   
43.
为探究羊经布鲁菌病疫苗(S2株)免疫后的血清抗体长期动态消长规律,本试验于2012年9月-2015年9月选取阿拉善盟阿拉善左旗96只山羊、100只绵羊作为试验动物,经布鲁菌疫苗(S2株)100亿CFU、200亿CFU不同免疫剂量灌服,分别于免疫前和免疫后不同时间段采血分离血清,应用虎红平板凝集试验和试管凝集试验进行抗体监测。结果表明,绵羊组在一免后20d时,血清抗体阳性率达到最高峰,之后呈下降趋势,150d抗体阳性率降至0%,免疫后180d^360d,绵羊组抗体阳性率一直处于较低水平(0%~4%),二免和三免后不同时间段免疫抗体消长规律与首次免疫基本一致;山羊组抗体阳性率在免疫后20 d时,血清抗体阳性率达到最高峰,之后呈下降趋势,免疫后90 d^360 d,免疫抗体时高时低,起伏较大,无明显规律,二免和三免后不同时间段免疫抗体消长规律与首次免疫基本一致,结果同时表明,100亿CFU和200亿CFU两个免疫剂量组的抗体阳性率无明显差异。  相似文献   
44.
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   
45.
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   
46.
不同质地土壤玉米秸秆还田配施腐熟剂效应的研究   总被引:5,自引:0,他引:5  
为研究鉴选不同质地土壤秸秆还田适宜的秸秆腐熟剂,于2017—2018年在西辽河平原灌区中壤土和砂壤土秸秆还田配施人元腐熟剂和中农绿康腐熟剂,以秸秆还田不施腐熟剂为对照,共设置6个处理,测定玉米秸秆腐解率、玉米产量、玉米根系特性和土壤化学性状,研究不同秸秆腐熟剂对玉米产量及土壤特性的影响。结果表明:不同质地土壤2种腐熟剂秸秆腐解率间无显著差异;中壤土2年各处理玉米产量及根系特性、土壤化学性状均表现为人元腐熟剂中农绿康腐熟剂秸秆还田不施腐熟剂,且中农绿康腐熟剂和人元腐熟剂显著高于秸秆还田不施腐熟剂,而2种腐熟剂处理之间无显著差异;砂壤土2年各处理玉米产量及根系特性、土壤化学性状均表现为中农绿康腐熟剂人元腐熟剂秸秆还田不施腐熟剂,且中农绿康腐熟剂显著高于人元腐熟剂和秸秆还田不施腐熟剂。2年不同质地土壤中配施腐熟剂在根系特性、土壤化学性状方面表现为砂壤土配施中农绿康腐熟剂效果优于人元腐熟剂,而中壤土配施2种腐熟剂效果无显著性差异。  相似文献   
47.
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   
48.
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   
49.

Background:

Hypertension is considered an independent risk factor for cardiovascular mortality in diabetic patients. The present study was designed to determine the role of gamma amino butyric acid B (GABAB) receptor and L-arginine (L-Arg) in GABA-induced vasorelaxation in normal and streptozotocin-induced diabetic rat vessels.

Methods:

Diabetes was induced by a single i.p. injection of streptozotocin (STZ, 60 mg/kg). Eight weeks later, superior mesenteric arteries of all groups were isolated and perfused according to the McGregor method.

Results:

Baseline perfusion pressure of STZ diabetic rats was significantly higher than non-diabetic rats in both intact and denuded endothelium. In the presence of faclofen, a selective GABAB receptor blocker, GABA-induced relaxation in intact and denuded endothelium mesenteric beds of STZ diabetic rats was suppressed, but this response in non-diabetic rats was not suppressed. Our results showed that in the presence of L-Arg, a nitric oxide precursor, GABA induced vasorelaxation in both diabetic and non-diabetic vessels.

Conclusion:

From the results of this study, it may be concluded that the vasorelaxatory effect of GABA in diabetic vessel is mediated by the GABAB receptor and nitric oxide, but it seems that in non-diabetic vessel GABAB receptor does not play any role in GABA-induced vasorelaxation, but nitric oxide induced GABA relaxation in non-diabetic vessel. Key Words: Gamma amino butyric acid (GABA), Diabetes, GABAB receptor  相似文献   
50.
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   
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