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1.
Mixed cropping of leguminous underseed species and cereal crops may increase productivity and serve some additional purposes. Two leguminous weed species which are widely distributed in annual crops of the Ethiopian highlands have been studied with varying coverage in greenhouse trials in Ethiopia with regard to their suitability as underseeds and with wheat ( Triticum turgidum [L.] Thell. var. durum [Desf.] MacKey) as a main crop. The competitive effects of Scorpiurus muricatus L. on the grain yield of wheat were smaller than those of Medicago polymorpha L. (-14.1 % and -23.6 % respectively, compared with the underseed free control) which is mainly ascribed to differences in their speed of development and shoot height. The residual effects of the underseed's root masses on the grain yield of the successive teff crop (Eragrostis tef [Zucc] Trotter) were significantly higher with Scorpiurus muricatus (+99.3 %) than with Medicago polymorpha (+63.6 %). The results are discussed with regard to the specific site conditions in the cereal-dominated cropping systems of the Ethiopian highlands.  相似文献   
2.
ObjectiveTo investigate complications associated with, and without, bupivacaine retrobulbar local anesthesia in dogs undergoing unilateral enucleation surgery.Study designRetrospective, observational study.AnimalsA total of 167 dogs underwent unilateral enucleation surgery via a transpalpebral approach.MethodsRecords from 167 dogs that underwent unilateral enucleation surgery that did (RB) or did not (NB) include retrobulbar bupivacaine anesthesia were reviewed, including anesthetic record, daily physical examination records, surgery report, patient discharge report and patient notes within 14 days of the surgery. Specific complications and severity were compared between RB and NB using the Wilcoxon rank-sum test. A ‘complication burden’ (0–5) comprising five prespecified complications was assigned and tested using rank-sum procedures. Statistical significance was set to 0.05.ResultsGroup RB included 97 dogs and group NB 70 dogs. Dogs in NB had a 17.0 percentage points (points) greater risk for a postoperative recovery complication (38.6% versus 21.6%; 95% confidence interval: 3.0–30.6 points; p = 0.017). There was inconclusive evidence that dogs in group RB had a lower risk of requiring perioperative anticholinergic administration (12.4% versus 22.9%; 10.5 points; p = 0.073). Other complications were similar between groups RB and NB with risks that differed by <10 points. The risk of hemorrhage was similar between groups RB (22.7%) and NB (20.0%) with no significant difference in the level of severity (p = 0.664).Conclusions and clinical relevanceIn this retrospective study, the use of retrobulbar bupivacaine for enucleation surgery in dogs was not associated with an increased risk of major or minor complications.  相似文献   
3.
随着分子遗传学的发展,已经鉴定出了影响剩余采食量(RFI)的大量数量性状位点和候选基因。有丝分裂原活化蛋白3激酶5(MAP3K5),也称凋亡信号调节激酶1(ASK1),属于MAPK超家族基因之一。目前,已有细胞外信号调节蛋白激酶(ERK)、c-Jun N-末端激酶(JNK)和p38丝裂原激活蛋白激酶(p38-MAPK)这3个MAPK家族成员在哺乳动物细胞中被克隆和鉴定,其主要作用机制是介导3条MAPKs信号通路,从而影响家畜的生长、体型及产奶性状等。课题组在前期对RFI的研究中筛选出与牛剩余采食量相关的MAP3K5基因,但其功能作用尚不明确,笔者在此基础上回顾了该基因的结构、生物学功能,概述了该基因在主要畜禽采食量变异及人类肥胖表型中的功能及作用,并从遗传学的角度重点分析了MAP3K5基因在畜禽RFI表型调控中的可能机制。通过对MAP3K5基因在畜禽RFI表型调控中的研究进展进行综述,期望为后期深入开展MAP3K5基因在畜禽采食量性状调控中的分子机制研究提供思路;对于其他可能通过MAP3K5基因影响畜禽表型的因素(如肠道菌群)有待进一步探讨。  相似文献   
4.
ObjectiveTo evaluate the efficacy of combined femoral and sciatic nerve blocks as an alternative to epidural anesthesia and analgesia in dogs undergoing stifle surgery under general anesthesia.Study designProspective, blinded, randomized, clinical comparison.AnimalsTwenty dogs weighing 37 ± 11 (mean ± SD) kg, aged 3 (1–8) [median (minimum–maximum)] years undergoing elective unilateral tibial-plateau leveling osteotomy.MethodsDogs were assigned randomly to receive either epidural anesthesia (bupivacaine 0.5%, 0.5 mg kg?1 + morphine 0.1%, 0.1 mg kg?1, in 0.2 mL kg?1; EPID) or femoral and sciatic nerve blocks (Bupivacaine 0.5%, 0.1 mL kg?1, was administered at each site; F + S) guided by electrolocation. All patients received a standard general anesthesia technique. Pain and sedation were scored (on scales of 0–10 and 0–3, respectively) pre-operatively, at extubation, and at 1, 4 and then every 4 hours thereafter up to 24 hours. Postoperatively, hydromorphone was administered to any patient with a pain score of >5 or whenever the blinded caregiver determined that more hydromorphone was necessary. Intraoperative heart rate (HR), mean arterial pressure (MAP), end tidal isoflurane (FE′ISO), body temperature, post-operative pain scores, time to first hydromorphone dose after surgery, time to first feeding, time to first drinking, time to first urination, time to first ambulation (walk on a lead) and cumulative dose of hydromorphone were recorded.ResultsIntra-operatively, FE′ISO and MAP were significantly lower in the EPID group (p = 0.05 and p = 0.04, respectively). Postoperatively, the cumulative hydromorphone consumption (p = 0.04) and the incidence of urinary retention (p = 0.03) were higher in the EPID group.Conclusion and clinical relevance F + S is a practical alternative to EPID that produces less urine retention and reduces opioid consumption in the 24 hours after surgery. EPID might be associated with a lower isoflurane requirement and lower systemic blood pressure.  相似文献   
5.
ObjectiveTo develop and describe an acoustic window to access and inject the retrobulbar region in donkey cadavers.Study designProspective cadaveric experimental study.AnimalsA total of 14 donkey cadaver heads.MethodsUltrasound landmarks for retrobulbar injection were identified by dissection of two cadavers. Ultrasound-guided retrobulbar injection of 3, 6 and 9 mL of contrast–lidocaine mixture (1:1) were evaluated using computed tomography (CT) in 12 cadavers for needle position and spread of injectate into the extraocular muscle cone.ResultsReal-time visualization of needle, extraocular muscle cone and optic nerve enabled successful intraconal instillation of injectate, as documented on CT images.Conclusions and clinical relevanceUltrasound-guided retrobulbar injections in cadaver donkeys provided adequate infiltration of the intraconal space.  相似文献   
6.

Objective

To compare left ventricular synchronization and systolic performance with transvenous pacing of the right ventricular apex (RVA), left ventricular free wall (LVF) or simultaneous pacing of the RVA and LVF (BiV).

Animals, materials and methods

Seven canine patients with complete heart block. Prospective study evaluating effect of pacing site. Twenty four hours following implantation of transvenous BiV pacing systems, electrocardiograms and echocardiograms were assessed during pacing from the: (1) Right Atrial Appendage/RVA (RAA/RVA), (2) RAA/LVF, and (3) RAA/BiV.

Results

QRS duration was significantly shorter with BiV pacing versus LVF pacing (p < 0.001), or RVA pacing (p < 0.001). Echocardiographic indices of systolic performance fractional shortening (FS), ejection fraction (EF), cardiac output (CO) were significantly higher with BiV pacing than with pacing from the RVA (P = 0.023, 0.006, and 0.002 respectively). Cardiac output, measured by the biplane Simpson's method, was higher with LVF versus RVA pacing (P = 0.036). There was no difference in FS or EF when comparing LVF to RVA pacing. Tissue Doppler measurements of synchronization and systolic performance did not show any difference between pacing mode, but a significantly increased number of segments were seen to contract following aortic valve closure during LVF pacing (P = 0.0268) and RVA pacing (P = 0.0197) as compared to BiV pacing.

Conclusions

Findings suggest that BiV pacing improves cardiac output and systolic performance versus RVA pacing. This improvement however, is not reflected in tissue Doppler indices of synchronization and systolic performance.  相似文献   
7.
为解决现有残膜回收机集膜装置在集膜和卸膜过程中残膜质地松散、作业效率低等问题,设计了一种带式卷膜装置.阐述了该带式卷膜装置的基本结构和工作原理,通过理论分析确定了关键部件结构参数,分析了卷膜作业过程,经过计算分析得到可卷收残膜膜卷的最大直径、卷膜速比范围、卷膜倾角范围.采用三因素三水平Box-Behnken试验设计方法...  相似文献   
8.
Sources of residual setup error after image guidance include image localization accuracy, errors associated with image registration, and inability of some treatment couches to correct submillimeter translational errors and/or pitch and roll errors. The purpose of this experimental study was to measure setup error after image‐guided correction of the canine intracranial region, using a four degrees‐of‐freedom couch capable of 1 mm translational moves. Six cadaver dogs were positioned 45 times as for clinical treatment using a vacuum deformable body cushion, a customizable head cushion, a thermoplastic mask and an indexed maxillary plate with a dental mould. The location of five fiducial markers in the skull bones was compared between the reference position and after megavoltage (MV), kilovoltage (kV) and cone‐beam computed tomography (CBCT)‐guided correction using orthogonal kV images. The mean three‐dimensional distance vectors (3DDV) after MV, kV and CBCT‐guided correction were 1.7, 1.5 and 2.2 mm, respectively. All values were significantly different (P < .01). The 95th percentiles of the 3DDV after online MV, kV and CBCT‐guided correction were 2.8, 2.6 and 3.6 mm, respectively. Residual setup error in the clinical scenario examined was on the order of millimetres and should be considered when choosing PTV margins for image‐guided radiation therapy of the canine intracranial region.  相似文献   
9.
抗生素类药物在蛋鸡养殖过程中起着非常重要的作用,但一直以来抗生素的使用缺乏科学的指导,致使抗生素残留在动物性食品和环境中,给生态系统和人类健康带来了巨大的威胁。从21世纪初开始,全球各个国家和相关国际组织采取相应的措施控制动物性食品中抗生素的残留,并逐渐加大了监察力度。文章对蛋鸡饲养过程中常用抗生素在鸡体内的消除和在鸡蛋中的残留规律进行综述,并根据我国部分省市鸡蛋中抗生素残留现状,综述影响鸡蛋抗生素残留的因素,拟为抗生素的合理使用和休药期的制订提供参考。  相似文献   
10.
This report describes transient trifascicular block in three cats presented with lethargy and inappetence, and elevated cardiac troponin I concentrations.The electrocardiogram (ECG) of cat 1 showed a sinus rhythm with pronounced first-degree atrioventricular (AV) block, right bundle branch block, and left anterior fascicular block. The ECG of cat 2 showed truncular left bundle branch block alternating with left anterior fascicular block coupled with prolonged PR intervals, second-degree heart block, and paroxysmal third-degree AV block. The ECG of cat 3 showed first-degree AV block with concomitant right bundle branch block. The diagnosis of trifascicular block was made when paroxysmal third-degree AV block was documented.All cats recovered with medical management within weeks. Each cat resumed a sinus rhythm. Elevated cardiac troponin I concentrations suggested myocarditis that improved.  相似文献   
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