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71.
To eliminate abnormal behaviors in leopards (Panthera pardus), such as stereotypic pacing, by utilizing environmental enrichment techniques, a proper understanding of their behavior in captive environments is required. Hence there is a need for animal welfare studies in Indian zoos. The activity budgets of 16 leopards were recorded across four southern Indian zoos: Thiruvananthapuram Zoo, Arignar Anna Zoological Park, Shri Chamarajendra Zoological Gardens, and the Guindy Children's Park. Of the 16 study animals, 14 were studied on‐exhibit on zoo holidays as well as on days with visitors present, and all 16 individuals were studied off‐exhibit on other days with visitors present. The 11 behaviors recorded were categorized into active, resting, and stereotypic behaviors. Leopards exhibited higher levels of activity in the on‐exhibit enclosures on days with no visitors. Feeding time influenced the behavioral repertoire of all 14 leopards studied on‐exhibit. Lower proportions of resting were exhibited during the hours before feeding. The proportion of active behaviors differed significantly across zoos. Stereotypic pacing levels were not influenced by the presence of visitors or by feeding time, but was significantly influenced by enclosure features. Higher levels of stereotypic pacing were exhibited in off‐exhibit than on‐exhibit enclosures. Our study shows that the behavior of captive leopards is influenced by enclosure type, feeding regime, and the presence of visitors. Zoo Biol 21:585–595, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
72.
Leaflet thrombosis following transcatheter aortic valve replacement (TAVR) and Valve-in-Valve (ViV) procedures has been increasingly recognized. This study aimed to investigate the effect of positioning of the transcatheter aortic valve (TAV) in ViV setting on the flow dynamics aspect of post-ViV thrombosis by quantifying the blood stasis in the intra-annular and supra-annular settings. To that end, two idealized computational models, representing ViV intra-annular and supra-annular positioning of a TAV were developed in a patient-specific geometry. Three-dimensional flow fields were then obtained via fluid-solid interaction modeling to study the difference in blood residence time (BRT) on the TAV leaflets in the two settings. At the end of diastole, a strip of high BRT (1.2s) region was observed on the TAV leaflets in the ViV intra-annular positioning at the fixed boundary where the leaflets are attached to the frame. Such a high BRT region was absent on the TAV leaflets in the supra-annular positioning. The maximum value of BRT on the surface of non-, right, and left coronary leaflets of the TAV in the supra-annular positioning were 53%, 11%, and 27% smaller compared to the intra-annular positioning, respectively. It was concluded that the geometric confinement of TAV by the leaflets of the failed bioprosthetic valve in ViV intra-annular positioning increases the BRT on the leaflets and may act as a permissive factor in valvular thrombosis. The absence of such a geometric confinement in the ViV supra-annular positioning leads to smaller BRT and subsequently less likelihood of leaflet thrombosis.  相似文献   
73.
Low pasture allowance during gestation affects ewes’ BW at parturition, the bond with their lamb, lamb development, and thus also may affect their responses to weaning. The objectives were to determine if native pasture allowance from before conception until late pregnancy affects ewe–lamb behaviours at lambing, ewes’ milk yield, lambs’ BW, and the behavioural and physiological changes of ewes and lambs at weaning. From 23 days before conception until 122 days of pregnancy, 24 ewes grazed on two different native pasture allowances: high (10 to 12 kg of dry matter (DM)/100 kg of BW per day; HPA treatment; n=12) or low (5 to 8 kg of DM/100 kg of BW per day; LPA treatment; n=12). Thereafter, all ewes grazed on Festuca arundinacea and received rice bran and crude glycerine. Ewes’ body condition score (BCS) and BW were recorded during pregnancy and postpartum periods. Milk yield was determined on days 32, 41 and 54 after lambing. Lambs’ BW was recorded from birth until 72 days after lambing. Latency from parturition until the ewe licked her lamb, maternal behaviour score (a test that evaluates maternal attachment to the lamb) and latency for lamb to stand up and suckle were determined. The behaviour of the lambs and ewes was recorded before and after weaning (at 65 days). The ewes’ serum total protein, albumin and globulin concentrations were measured before and after weaning. The HPA ewes presented greater BW (P<0.005) and BCS (P<0.005) than the LPA ewes during pregnancy and postpartum (P<0.04), and had a greater milk yield than the LPA ewes (P<0.03). Treatments did not influence any behaviour at lambing, lambs’ BW, neither the ewes’ behavioural and physiological changes at weaning. HPA lambs paced and vocalized more than LPA lambs (P<0.0001). The variation of albumin concentration before and after weaning was greater in the HPA lambs than in the LPA lambs (P<0.0001). In conclusion, although ewes’ BW, BCS and milk production were affected by pasture allowance until late pregnancy, this did not affect the behaviours that lead to the establishment of the mother–young bond, nor the ewes’ behavioural responses at weaning. Lambs reared by ewes that grazed on low pasture allowance during pregnancy presented fewer behavioural changes and a lower decrease of albumin concentration after weaning. Lambs’ BW was not affected by the feeding received by their mothers.  相似文献   
74.
目的:探讨沙利度胺对原发性肝癌(HCC)介入后血管内皮生长因子(VEGF)及生存质量的影响。方法:将2014年1月至2016年1月期间我院收治的拟行肝动脉栓塞化疗(TACE)的HCC患者60例按照随机数字表法分为A、B两组,各30例。A组患者采用TACE+沙利度胺治疗,每晚200 mg,口服一个月;B组患者单行TACE治疗。分别于治疗前、治疗后3周检测两组患者的VEGF水平,于治疗前、治疗后1个月应用生存质量评分量表(QOL)评价患者生存质量,并比较两组患者治疗前后的体重及治疗过程中的不良反应。结果:治疗前两组患者血清VEGF水平差异无统计学意义(P0.05)。治疗后两组患者VEGF水平均较治疗前升高,其中A组患者治疗后VEGF水平显著低于B组患者(P0.01)。治疗前两组患者QOL分数和体重比较差异无统计学意义(P0.05)。而治疗后两组患者的QOL分数较治疗前均有所降低,但A组患者的QOL分数显著高于B组患者(P0.05),而两组患者治疗后的体重无统计学差异(P0.05)。A组30例患者中有1例(3.33%)患者因严重嗜睡、2例(6.67%)患者因严重口腔干燥而终止口服沙利度胺,其余27例患者均能耐受。结论:沙利度胺联合TACE方法治疗HCC可降低VEGF水平和改善癌症患者的生存质量,值得在临床上推广使用。  相似文献   
75.
Cardiac resynchronization therapy (CRT) is a promising therapy for heart failure patients with a conduction disturbance, such as left bundle branch block. The aim of CRT is to resynchronize contraction between and within ventricles. However, about 30% of patients do not respond to this therapy. Therefore, a better understanding is needed for the relation between electrical and mechanical activation. In this paper, we focus on to what extent animal experiments and mathematical models can help in order to understand the pathophysiology of asynchrony to further improve CRT.  相似文献   
76.
为了探讨锥形束CT (DynaCT)在肝癌患者实施经导管肝动脉化疗栓塞(TACE)手术治疗中的指导作用、栓塞效果评估中的价值,本研究选取了2012年3月至2015年5月在本院实施TACE手术治疗的102例原发性肝癌或转移性肝癌患者进行研究。通过对102例患者病灶进行手术前螺旋CT检测、术中数字减影血管造影(DSA)及DynaCT检测,并对比DSA与DynaCT对肝癌病灶、供血动脉、术后栓塞效果的检测结果。本研究发现术前普通螺旋CT共计检出病灶105个,术中DSA检出病灶数目176个,DynaCT术中检出肿瘤病灶285个;DynaCT和DSA的平均检出病灶数目均显著的高于普通螺旋CT (p<0.05),DynaCT平均检出病灶数目均显著的高于DSA (p<0.05);DynaCT的病灶供血动脉检出率为86.67%,显著地高于DSA (55.68%)(p<0.05);DynaCT检出的285个病灶对栓塞效果评估结果与实际栓塞效果一致的有271个病灶(95.09%),DSA评估结果与实际结果一致的有138个病灶(78.41%),DynaCT对于TACE术后效果评估的一致性高于DSA (p<0.05)。本研究表明,DynaCT在肝癌患者实施TACE手术治疗中能够更有效的发现病灶,指导栓塞操作。  相似文献   
77.
IntroductionDespite considerable advances in the last decade, major adverse events remain a concern after transcatheter aortic valve implantation (TAVI). The aim of this study was to provide a detailed overview of their underlying causes and contributing factors in order to identify key domains for quality improvement.MethodsThis observational, prospective registry included all patients undergoing TAVI between 31 December 2015 and 1 January 2020 at the St. Antonius Hospital in Nieuwegein and the University Medical Centre in Utrecht. Outcomes of interest were all-cause mortality, stroke, major bleeding, life-threatening or disabling bleeding, major vascular complications, myocardial infarction, severe acute kidney injury and conduction disturbances requiring permanent pacemaker implantation within 30 days after TAVI, according to the Valve Academic Research Consortium‑2 criteria.ResultsOf the 1250 patients who underwent TAVI in the evaluated period, 146 (11.7%) developed a major complication. In 54 (4.3%) patients a thromboembolic event occurred, leading to stroke in 36 (2.9%), myocardial infarction in 13 (1.0%) and lower limb ischaemia in 11 (0.9%). Major bleeding occurred in 65 (5.2%) patients, most frequently consisting of acute cardiac tamponade (n = 25; 2.0%) and major access-site bleeding (n = 21; 1.7%). Most complications occurred within 1 day of the procedure. Within 30 days a total of 54 (4.3%) patients died, the cause being directly TAVI-related in 30 (2.4%). Of the patients who died from causes that were not directly TAVI-related, 14 (1.1%) had multiple hospital-acquired complications.ConclusionA variety of underlying mechanisms and causes form a wide spectrum of major threats affecting early safety in 11.7% of patients undergoing TAVI in a contemporary cohort of real-world patients.Supplementary InformationThe online version of this article (10.1007/s12471-021-01638-8) contains supplementary material, which is available to authorized users.  相似文献   
78.
BackgroundSymptomatic tricuspid regurgitation (TR) is increasingly prevalent and impairs quality of life and survival, despite medical treatment. Transcatheter tricuspid valve repair (TTVR) has recently become available as a treatment option for patients not eligible for tricuspid valve surgery. In this study we describe the early experience with TTVR in the Netherlands.MethodsAll consecutive patients scheduled for TTVR in two tertiary hospitals were included in the current study. Patients were symptomatic and had severe functional TR. TTVR was performed either with the MitraClip (off-label use) or dedicated TriClip delivery system and device. Procedural success was defined as achievement of clip implantation, TR reduction ≥ 1 grade and no need for re-do surgical or transcatheter intervention. Clinical improvement was evaluated after 4 weeks.ResultsTwenty-one patients (median age 78 years, 33% male, 95% New York Heart Association class ≥ 3, 100% history of atrial fibrillation) underwent TTVR. Procedural success was achieved in 16 patients, of whom 15 reported symptomatic improvement (New York Heart Association class 1 or 2). There was no in-hospital mortality and no major complications occurred. Baseline glomerular filtration rate and TR coaptation gap size were associated with procedural success.ConclusionThe current study showed that TTVR seems a promising treatment option for patients with severe functional TR deemed high risk for surgery. Successful TR reduction is most likely in patients with limited coaptation gap size and strongly determines clinical benefit. Adequate patient selection and timing of treatment seem essential for an optimal patient outcome.Supplementary InformationThe online version of this article (10.1007/s12471-021-01613-3) contains supplementary material, which is available to authorized users.  相似文献   
79.
摘要 目的:探讨仑伐替尼联合肝动脉化疗栓塞术(TACE)对不可切除肝细胞癌患者肿瘤标志物、凋亡分子和血清唾液酸转移酶1(ST6Gal1)、血管生成素-2(ANG-2)、肝细胞生长因子(HGF)的影响。方法:采用随机数字表法将四川绵阳四0四医院2020年3月~2022年12月期间收治的114例不可切除肝细胞癌患者分为对照组(n=57,TACE治疗)和研究组(n=57,仑伐替尼联合TACE治疗)。对比两组疗效、肿瘤标志物[甲胎蛋白(AFP)、糖类抗原199(CA199)、癌胚抗原(CEA)]、血清凋亡分子[B淋巴细胞瘤-2相关X蛋白(Bax)、B淋巴细胞瘤-2基因(Bcl-2)、存活素(Survivin)、半胱氨酸天冬氨酸蛋白酶-4(Caspase-4)]和血清ST6Gal1、ANG-2、HGF水平,并观察两组治疗期间不良反应发生情况。结果:与对照组相比,研究组的临床总有效率更高(P<0.05)。与对照组相比,研究组治疗后AFP、CA199、CEA水平更低(P<0.05)。与对照组相比,研究组治疗后Bcl-2、Survivin水平更低,Bax、Caspase-4水平更高(P<0.05)。与对照组相比,研究组治疗后ST6Gal1、ANG-2、HGF水平更低(P<0.05)。两组不良反应总发生率组间对比未见差异(P>0.05)。结论:仑伐替尼联合TACE用于不可切除肝细胞癌患者,可提高临床治疗效果,调节肿瘤标志物、凋亡分子和血清ST6Gal1、ANG-2、HGF水平,安全性较好。  相似文献   
80.
Inadvertent lead placement in the left ventricle (LV) is an uncommon and often under-diagnosed complication of cardiac device implantation. Thromboembolic (TE) events are common and usually secondary to fibrosis or thrombus formation on or around the lead. Anticoagulation can prevent TE events. Percutaneous and surgical LV lead extractions have been performed successfully, but the risks of percutaneous lead removal are not well-defined. In this report, we describe a case of inadvertent LV lead placement and briefly review the contemporary literature.  相似文献   
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