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81.
Alexander Valverde DVM DVSc DACVA Giacomo Gianotti DVM Eva Rioja DVM PhD DVSc DACVA Amanda Hathway RVT 《Journal of Veterinary Emergency and Critical Care》2011,21(4):328-334
Objective – To compare the determination of cardiac output (CO) via arterial pulse pressure waveform analysis (FloTrac/Vigileo) versus lithium dilution method. Design – Prospective study. Setting – University teaching hospital. Animals – Six adult dogs. Interventions – Dogs were instrumented for CO determinations using lithium dilution (LiDCO) and FloTrac/Vigileo methods. Direct blood pressure, heart rate, arterial blood gases, and end‐tidal isoflurane (ETIso) and CO2 concentrations were measured throughout the study while CO was manipulated with different depth of anesthesia and rapid administration of isotonic crystalloids at 60 mL/kg/h. Measurements and Main Results – Baseline CO measurements were obtained at 1.3% ETIso and were lowered by 3% ETIso. Measurements were obtained in duplicate or triplicate with LiDCO and averaged for comparison with corresponding values measured continuously with the FloTrac/Vigileo method. For 30 comparisons between methods, a mean bias of ?100 mL/kg/min and 95% limits of agreement between ?311 and +112 mL/kg/min (212 mL/kg/min) was determined. The mean (mL/kg/min) of the differences of LiDCO?Vigileo=62.0402+?0.8383 × Vigileo, and the correlation coefficient (r) between the 2 methods 0.70 for all CO determinations. The repeatability coefficients for the individual LiDCO and FloTrac/Vigileo methods were 187 and 400 mL/kg/min, respectively. Mean LiDCO and FloTrac/Vigileo values from all measurements were 145 ± 68 mL/kg/min (range, 64–354) and 244 ± 144 mL/kg/min (range, 89–624), respectively. The overall mean relative error was 48 ± 14%. Conclusion – The FloTrac/Vigileo overestimated CO values compared with LiDCO and the relative error was high, which makes this method unreliable for use in dogs. 相似文献
82.
紫花苜蓿不同品种对卡那霉素敏感性分析 总被引:2,自引:0,他引:2
组织培养条件下卡那霉素(Kan)对不同紫花苜蓿品种(秘鲁、富平、甘农3号)愈伤组织诱导及芽分化的影响进行了研究,实验结果表明:不同的外植体对卡那霉素的敏感性差异较大,不同品种间也存在差异。子叶对卡那霉素的敏感性高于下胚轴,当卡那霉素的浓度为20mg/L时,子叶的愈伤率极低。子叶愈伤阶段卡那霉素的有效工作浓度为15~18mg/L,分化阶段为40mg/L。下胚轴对卡那霉素的敏感性因品种不同:秘鲁苜蓿愈伤阶段的选择压为60mg/L,分化阶段以50mg/L为宜。富平苜蓿和甘农3号苜蓿愈伤阶段的选择压力分别为80mg/L9、0mg/L,分化阶段选择压降低到60mg/L。另外,如果在愈伤阶段加入选择压,后期分化中应适当降低压力或除去压力,以利于体细胞胚的产生和发育。 相似文献
83.
OBJECTIVE: To evaluate the effects on intraocular pressure (IOP), pupillary diameter (PD), blepharospasm score, conjunctival injection score, and aqueous humor flare score when either 0.03% bimatoprost solution is applied once daily or 0.15% unoprostone isopropyl solution is applied twice daily topically to the eyes of normal cats. MATERIALS AND METHODS: The aforementioned parameters were evaluated daily in each of 12 cats throughout the entirety of the study. During an initial 10-day treatment phase a single eye of six of the cats was treated with 0.03% bimatoprost solution while a single eye of the remaining six cats was treated with buffered saline solution (BSS) once daily. During a second 10-day treatment phase a single eye of six of the cats was treated with 0.15% unoprostone isopropyl solution while a single eye of the remaining six cats was treated with BSS twice daily. Contralateral eyes of all cats remained untreated at all time points. RESULTS: Blepharospasm score, conjunctival injection score, and aqueous humor flare score never rose from a value of 0, for any eye of any cat during the study. The mean +/- SD of IOP for eyes treated with 0.03% bimatoprost solution and BSS were 16.55 +/- 3.06 mmHg and 18.02 +/- 3.52 mmHg, respectively. The mean +/- of PD for eyes treated with 0.03% bimatoprost solution and BSS were 5.7 +/- 1.57 mm and 6.39 +/- 1.78 mm, respectively. The mean +/- SD of IOP for eyes treated with 0.15% unoprostone isopropyl solution and BSS were 15.7 +/- 2.91 mmHg and 17.2 +/- 2.9 mmHg, respectively. The mean +/- SD of PD for eyes treated with 0.15% unoprostone isopropyl solution and BSS were 5.8 +/- 1.43 mm and 6.9 +/- 1.37 mm, respectively. There was no significant difference (P > or = 0.05) in IOP or PD between eyes treated with 0.03% bimatoprost solution vs. eyes treated with BSS. Similarly, there was no significant difference (P > or = 0.05) in IOP or PD between eyes treated with 0.15% unoprostone isopropyl solution vs. eyes treated with BSS. CONCLUSION: Neither once daily topical administration of 0.03% bimatoprost solution nor twice daily topical administration of 0.15% unoprostone isopropyl solution significantly affect the IOP of normal cats. Both 0.03% bimatoprost solution and 0.15% unoprostone isopropyl solution induced no significant ocular side effects in normal cats when dosed over a 10-day treatment period. 相似文献
84.
Garofalo NA Teixeira Neto FJ Alvaides RK de Oliveira FA Pignaton W Pinheiro RT 《Veterinary anaesthesia and analgesia》2012,39(4):324-334
ObjectiveTo evaluate the agreement between invasive blood pressure (IBP) and Doppler ultrasound blood pressure (DUBP) using three cuff positions and oscillometric blood pressure (OBP) in anesthetized dogs.Study designProspective study.AnimalsNine adult dogs weighing 14.5–29.5 kg.MethodsThe cuff was placed above and below the tarsus, and above the carpus with the DUBP and above the carpus with the OBP monitor. Based on IBP recorded via a dorsal pedal artery catheter, conditions of low, normal, and high systolic arterial pressures [SAP (mmHg) <90, between 90 and 140, and >140, respectively] were induced by changes in isoflurane concentrations and/or dopamine administration. Mean biases ± 2 SD (limits of agreement) were determined.ResultsAt high blood pressures, regardless of cuff position, SAP determinations with the DUBP underestimated invasive SAP values by more than 20 mmHg in most instances. With the DUBP, cuff placement above the tarsus yielded better agreement with invasive SAP during low blood pressures (0.2 ± 16 mmHg). The OBP underestimated SAP during high blood pressures (?42 ± 42 mmHg) and yielded better agreement with IBP for mean (MAP) and diastolic (DAP) arterial pressure measurements [overall bias: 2 ± 15 mmHg (MAP) and 0.2 ± 16 mmHg (DAP)].ConclusionsAgreement of SAP determinations with the DUBP is poor at SAP > 140 mmHg, regardless of cuff placement. Measurement error of the DUBP with the cuff placed above the tarsus is clinically acceptable during low blood pressures. Agreement of MAP and DAP measurements with this OBP monitor compared with IBP was clinically acceptable over a wide pressure range.Clinical relevanceWith the DUBP device, placing the cuff above the tarsus allows reasonable agreement with IBP obtained via dorsal pedal artery catheterization. Only MAP and DAP provide reasonable estimates of direct blood pressure with the OBP monitor evaluated. 相似文献
85.
86.
日粮能量和蛋白水平对双向选择血浆极低密度脂蛋白浓度肉鸡腹脂和产肉性能的影响 总被引:1,自引:0,他引:1
对708只(公母各半)5~9周龄一世代高、低极低密度脂蛋白(VLDL)系肉鸡进行3个代谢能水平(13.4,12.5,11.6MJ/kg)和3个粗蛋白水平(22.4%,19.4%,16.4%)的三因子交叉的遗传-营养互作试验,以探讨肉鸡腹脂及屠体性状的遗传、营养、性别间的互作效应。结果表明:日粮对脂肪沉积的影响存在品系差异,品系与日粮代谢能互作对板油有明显影响(P<0.05);日粮代谢能和粗蛋白对高VLDL系板油的影响大于低VLDL系,高VLDL系板油随日粮代谢能的升高而升高,而低VLDL系无此规律。品系与日粮代谢能互作对肌胃脂率有明显影响(P<0.05),日粮代谢能对低VLDL系肌胃脂的影响大于高VLDL系,而粗蛋白对高VLDL系肌胃脂的影响大于低VLDL系。品系间肌胃脂的差异在不同日粮代谢能水平下表现不一致。品系与日粮互作对产肉性状未产生明显影响。日粮代谢能与性别间的互作对腿肌率有明显影响(P<0.05),雌性腿肌率随代谢能水平的升高而降低。 相似文献
87.
本试验旨在研究低磷低鱼粉饲料中添加植酸酶和蛋白酶对草鱼生长性能、消化酶活性、营养物质表观消化率和免疫力的影响。试验选取平均体重为9.66 g的健康草鱼630尾,随机分为7个组,每组3个重复,每个重复30尾鱼。7组草鱼饲喂如下试验饲料:正常磷(磷酸二氢钙添加量2.0%)正常鱼粉(鱼粉添加量3.0%)饲料(对照)、低磷(磷酸二氢钙添加量1.3%)正常鱼粉饲料、低磷正常鱼粉并添加0.03%植酸酶饲料、正常磷低鱼粉(鱼粉添加量1.5%)饲料、正常磷低鱼粉并添加0.05%蛋白酶饲料、低磷和低鱼粉饲料、低磷低鱼粉并添加0.03%植酸酶和0.05%蛋白酶饲料。饲养试验持续56 d。结果显示:与饲喂正常磷正常鱼粉饲料草鱼相比,饲喂低磷低鱼粉饲料草鱼的增重率、特定生长率、营养物质(干物质、蛋白质、钙和磷)表观消化率、肠道消化酶(胰蛋白酶、糜蛋白酶和淀粉酶)活性、血清溶菌酶活性均显著降低(P<0.05),饲料系数和血清丙二醛含量显著升高(P<0.05)。在低磷正常鱼粉饲料、正常磷低鱼粉饲料、低磷低鱼粉饲料中分别添加植酸酶、蛋白酶、植酸酶与蛋白酶后,草鱼的上述指标均得到显著改善(P<0.05)。以上结果表明,在低磷低鱼粉饲料中添加植酸酶和蛋白酶能够提高草鱼的营养物质表观消化率、肠道消化酶活性和免疫力,从而改善其生长性能。 相似文献
88.
The combined occurrence of ocular pigment deposition and glaucoma has been described in Cairn Terriers. Recently, this condition was also observed in two other breeds: the Boxer (two cases) and the Labrador Retriever (one case). Six dogs were referred to the Ophthalmology section of the Department of Clinical Sciences of Companion Animals and to a private referral clinic because of glaucoma or blindness in one or both eyes. In five cases ophthalmic examination showed pigment depositions in the sclera around the entire circumference of the perilimbal zone. Eight enucleated eyes (four eyes of two Cairn Terriers, three eyes of two Boxers and one eye of a Labrador Retriever) were examined microscopically. All eyes showed the same findings: an extensive infiltration of large melanin-containing cells with an eccentric nucleus, located in the iris, ciliary body, retina, choroids and sclera. Transmission electron microscopy of two of the examined eyes revealed that the morphology of most of these cells was consistent with melanophages. While reports in the veterinary literature concerning this condition are limited the cells concerned have been described to be melanocytes. Further research is needed to conclusively identify the cell type. As described in the present report, the histologic and transmission electron microscopic findings suggest a different etiology of the ocular pigment deposition and glaucoma compared with the pigment dispersal syndrome in humans. 相似文献
89.
90.
钼酸钠对低温胁迫下狼尾草渗透调节物质和膜稳定性的影响 总被引:2,自引:0,他引:2
以狼尾草(Pennisetum alopecuroides)为材料,研究了不同质量浓度的钼酸钠对低温胁迫下狼尾草幼苗中几种渗透调节物质含量和细胞膜稳定性的影响。结果表明,钼酸钠可显著提高低温胁迫下的狼尾草叶片总叶绿素、可溶性蛋白质、抗坏血酸、可溶性糖、游离脯氨酸等物质的含量,降低丙二醛含量和细胞膜透性,缓解狼尾草受到的低温冷害;钼酸钠缓解低温胁迫的最低效应质量浓度为0.5 mg·L-1,且在0.5~5.0 mg·L-1质量浓度范围内对狼尾草渗透调节物质和细胞膜稳定性的影响无显著差异。 相似文献