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21.
基于田块尺度采集农田表层土壤样品120件,采用绝对因子分析/多元线性回归(APCS-MLR)受体模型与地统计学分析对研究区域内As、Cd、Cu、Cr、Mn、Ni、Pb和Zn这8种重金属污染空间分布特征及来源进行解析,利用地累积指数和潜在生态风险指数法评价土壤生态风险。研究结果表明:研究区表层土壤中8种重金属含量差异较大,As、Cd和Cr点位超标率分别为61.83%、90.83%和92.52%,土壤重金属Zn、Cu、Cr和Ni主要以残渣态存在(占比在80%以上)。土壤中Cd、Cr和Cu含量空间分布格局呈东南部较高、中部次之、西北部较低的趋势,而Mn、Ni、Pb和Zn含量的空间分布格局与此相反。APCS-MLR模型表明研究区域土壤重金属As、Cr、Cu和Ni的来源以自然源为主,占比分别为39.34%、47.32%、44.53%和50.23%; Pb、Zn的来源以工业活动源和交通源为主,占比分别为31.93%、30.53%和23.36%、22.17%; Cd的农业活动源占比为53.63%。土壤pH与有效态As、Cd、Cu和Ni含量呈极显著负相关性(P<0.01),土壤有机质与有效态As、Cd和Cr呈极显著负相关性(P<0.01)。地累积指数显示土壤Cr总体处于中、重度污染水平,其次是Cd;生态危害指数也表明Cr和Cd是主要生态危害元素,潜在生态危害系数变化范围分别为5.20~41.12和11.56~113.35。总体来看,研究区域Cr和Cd污染较为严重,存在潜在风险,应采取安全利用和修复等措施,降低其风险水平。  相似文献   
22.
目的分析通过刺络拔罐配合静力练习治疗急性踝关节扭伤的临床疗效。方法收集2009年-2013年病例共71例,根据治疗方案随机分为观察组36例、对照组35例,观察组采用刺络拔罐配合静力练习治疗,对照组采用单纯刺络拔罐治疗。7 d为1个疗程,1个疗程后观察疗效,2个月后复查或随访患者,评价踝关节Kofoed评分。结果两组治疗后临床疗效比较,差异有统计学意义(P<0.05)。2个月后评价踝关节Kofoed评分,观察组与对照组比较,差异有统计学意义(P<0.05)。结论急性踝关节扭伤通过刺络拔罐配合静力练习治疗效果优于单纯刺络拔罐治疗。  相似文献   
23.

Background

Outcomes of colic treatment are of great interest to clinicians, horse owners and insurers. One commonly used criterion of success is the overall short-term survival rate. This is used as to compare treatments and to measure quality of veterinary care, but may be biased by demographic or social factors such as attitudes towards animal suffering and euthanasia. The aims of this study were to 1) describe and analyse characteristics in horses with signs of colic referred to the University Hospital for Large Animals (UHLA), University of Copenhagen, Denmark over a 10-year period and 2) to compare these rates with those published in other comparable studies.

Results

The overall survival rate for colic horses over the 10-year study period was 68% (confidence intervals (CI): 66–71%; 1087/1588). In the medical group, 1093 horses, short-term survival was 87% (CI: 85–89%). Thirty one % of referred horses were given diagnoses requiring surgical intervention (CI: 29–33%). In this group 32% of the horses were euthanized before surgery (CI: 28–36%; 159/495). Of the surgical cases 27% (CI: 23-31%) were euthanized or died during surgery. Of the horses that recovered from surgery 25% died or were euthanized (CI: 19–32%; 48/189), while 75% survived to discharge (CI: 68–81%).

Conclusions

The short term survival rates of Danish horses with colic were similar or lower to those reported from other countries. Apart from variability of veterinary care, attitudes towards euthanasia vary among the countries, which may bias the outcomes. This study indicates that qualitative interview studies on owners’ attitudes towards animal suffering and euthanasia need to be conducted. Our opinion is that survival rates are not valid as sole indicators of quality of care in colic treatment due to selection bias. If the survival rates are to be compared between hospitals, techniques or surgeons, prospective studies including mutually agreed-on disease severity scores and a predefined set of reasons for euthanasia are needed.  相似文献   
24.
Previous work has hypothesised that cows in low body condition become lame. We tested this in a prospective longitudinal study. Body condition score (BCS), causes of lameness and milk yield were collected from a 600-cow herd over 44-months. Mixed effect binomial models and a continuous outcome model were used to investigate the associations between lameness, BCS and milk yield. In total, 14,320 risk periods were obtained from 1137 cows. There were 1510 lameness treatments: the most common causes of lameness were sole ulcer (SU) (39%), sole haemorrhage (SH) (13%), digital dermatitis (DD) (10%) and white line disease (WLD) (8%). These varied by year and year quarter. Body condition was scored at 60-day intervals. BCS ranged from 1 to 5 with a mean of 2.5, scores were higher in very early lactation but varied widely throughout lactation; approximately 45% of scores were <2.5. The key finding was that BCS < 2.5 was associated with an increased risk of treatment for lameness in the following 0–2 months and >2–4 months for all causes of lameness and also specifically for SU/WLD lameness. BCS < 2.5 was associated with an increased risk of treatment for SH in the following 0–2 months but not >2–4 months. There was no such association with DD. All lameness, SU/WLD, SH and DD were significantly more likely to occur in cows that had been lame previously, but the effect of BCS was present even when all repeat cases of lameness were excluded from the analysis. Milk yield was significantly higher and fell in the month before treatment in cows lame with SU/WLD but it was not significantly higher for cows that were treated for DD compared with non-lame cows. These findings support the hypothesis that low BCS contributes to the development of horn related claw lameness but not infectious claw diseases in dairy cows. One link between low BCS and lameness is a thin digital cushion which has been proposed as a trigger for claw horn disease. Cows with BCS 2 produced more milk than cows with BCS 2.5, however, this was only approximately 100 kg difference in yield over a 305-day lactation. Given the increased risk of lameness in cows with BCS 2, the direct costs of lameness and the small variability in milk yield by BCS, preventing cows from falling to BCS < 2.5 would improve cow welfare and be economically beneficial.  相似文献   
25.
[目的]为了充分了解牛群的体型外貌及生理指标情况,我们对牛群体型外貌进行了评定、同时对牛群的毛色、肤色、踢、角及生理指标进行了调查研究。[方法]通过对牛群生理指标测定、体型外貌评定及毛色、肤色、踢、角颜色和形状分析。[结果]表明:蜀宣花牛肉用指数公母牛分别为5.3769和4.0725,低于国外专门化肉牛品种,但也明显高于国内几个比较有名的地方牛品种,由此说明,蜀宣花牛的肉用指数界于专用型肉牛和肉役兼用型牛之间。毛色以黄白花和红白花为主,占90.16%;皮肤颜色以纯粉色和粉色有斑点的为主,占96.92%;蹄质颜色以纯蜡黄色为主,占86.28%;角型以照阳角为主,占93.94%。成年母牛的生理指标分别为:体温平均38.38℃、心跳74.56次/min、呼吸18.74次/min和瘤胃蠕动2.84次/2min;体型外貌线性评定分析表明,蜀宣花牛母牛的14个性状中,除后房宽度、尻角度和乳房底部3个性状平均分略低于75分,强壮度、后房高度、乳头位置和乳静脉4个性状的平均分高于80分外,其余7个性状的平均分都在75~80分之间。[结论]从乳用性能的角度看,牛群的平均体型尚处在较理想型和理想型之间,还有待进一步选育提高。  相似文献   
26.
乌龟肌肉营养价值的评定   总被引:4,自引:0,他引:4  
分析结果表明,乌龟的水分、总糖、灰分含量分别为80 24%,0 66%和0 95%。乌龟肌肉的蛋白质含量达16 64%,必需氨基酸和鲜味氨基酸分别占氨基酸总量的49 16%和43 39%,氨基酸组成中以Glu含量最为丰富,Ie是第一限制性氨基酸,氨基酸分为82 63;乌龟肌肉脂肪含量为1 51%,脂肪酸组成以C18∶1为主,达39.32%,其次为C16∶0及C22∶6,不饱和脂肪酸占脂肪酸总量的76 83%。  相似文献   
27.
In obese humans, mesenchymal stem cells differentiate to become ectopic fat cells in muscles. These ectopic fat cells inhibit the contraction of vascular smooth muscles. Stem cells have been recently identified in the human oviduct, a structure important in reproduction. We therefore investigated the number of Oil Red O (ORO)‐positive cells in the oviducts of control Japanese Black cows (n = 6; body condition score [BCS], 3.0 on a 5‐point scale) compared to those with diet‐induced obesity (n = 5; BCS, 4.0). We stained the ampulla and isthmus collected on the second day after ovulation with ORO and then counted the positive cells in each layer in 10 cross‐sections of the ampulla or isthmus. The obese group (23.4 ± 3.4 in the 10 sections) had larger numbers of ORO‐positive cells in the longitudinal muscularis of the isthmus (P < 0.05) than did the control group (15.0 ± 2.4). ORO‐positive cells were also observed in all other layers of the isthmus and ampulla; however, the number of cells in these layers did not differ significantly between obese cows and controls. Whether this observed increase in ORO‐positive cells in the oviducts of obese cows affects their reproduction warrants further study.  相似文献   
28.
及时高效预测和筛查潜在农药污染场地对环境污染风险管控具有重要意义。基于万维网公开的46个农药场地样本数据,利用五分制层次分析法建立农药场地土壤污染快速预测指标体系,包括产品特征、局部气候条件、土壤属性和场地生产特征4个因素及其相应的产品毒性、持久性、气温、降水、风速、光照、土壤质地、土壤pH、有机质含量、生产时间和闲置时间11个特征指标。其中,农药场地生产时间、产品毒性及其持久性指标五分制分级后与农药场地土壤污染均存在显著线性相关性,三个指标不同组合对场地土壤污染的线性综合预测精度小于65%,而基于11个指标的机器学习方法综合预测精度为82%,但存在污染场地严重漏判问题。以综合评价指数值P≥0.6作为农药场地土壤污染的预测阈值,五分制层次分析法综合预测精度达到91%,优于线性预测以及机器学习方法,具有关键数据需求少、预测快速高效特点,体现 “宁严勿漏”的预测原则,可用于各类型农药场地的土壤污染筛查。  相似文献   
29.
模拟比较了随机选择、标记值选择及BLUP选择3种背景选择方法在标记辅助导入(利用标记辅助将供体群中的一个有利QTL等位基因导入到受体群中)的选择效果。前景选择是借助与目标基因连锁的两侧标记对目标基因进行间接选择。研究结果表明,在背景选择中,利用标记值选择能使受体基因组很快得到恢复,2个世代的回交就能恢复90%以上,4个世代的回交就能完全恢复。利用BLUP选择虽然不能使受体基因组迅速全部恢复,但能使特定的背景性状得到最大的遗传进展。  相似文献   
30.
ObjectiveComparison of the analgesic effect of buprenorphine at 20 or 40 μg kg?1.Study designAn investigator ‘blinded’, randomised study.AnimalsTwenty six dogs presented for ovariohysterectomy.MethodsDogs were premedicated intramuscularly with acepromazine 0.03 mg kg?1 and buprenorphine at either 20 (B20, n = 12) or 40 μg kg?1 (B40, n= 14) followed by anaesthetic induction with propofol and maintenance with isoflurane. During anaesthesia non invasive blood pressure, heart rate, respiratory rate, blood oxygen saturation, inspired and expired volatile agent, end-tidal carbon dioxide and ECG were recorded. Pain and sedation were assessed using interactive VAS scores; mechanical nociceptive thresholds were measured at the wound and hindlimb - all were assessed before and up to 22 hours after administration. Carprofen was used for rescue analgesia.ResultsThere were no significant differences between the two groups for any of the parameters examined. Rescue analgesia was required around 5 hours after administration of buprenorphine in a significant number of animals. Sedation was good preoperatively and scores decreased over time postoperatively. Hock thresholds did not change over time; wound thresholds decreased significantly compared to the baseline value from 3 hours onwards.ConclusionsAdministration of buprenorphine at either 20 or 40 μg kg?1 IM with acepromazine provided good pre-operative sedation. Cardiovascular and respiratory values remained within clinically acceptable limits during anaesthesia. There was no evidence that increasing dose increased adverse events that may be associated with opioid administration (e.g. bradycardia and respiratory depression).Clinical relevanceIncreasing the dose of buprenorphine from 20 to 40 μg kg?1 did not provide any benefits with respect to analgesia after ovariohysterectomy as assessed using the VAS scoring system.  相似文献   
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