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991.
The objective of the study was to describe the effects of carbon dioxide pneumoperitoneum and Trendelenburg position on arterial blood gas values in horses anesthetized for laparoscopy. The study design was a prospective case series using 14 healthy adult horses anesthetized for elective laparoscopic surgery. All horses in the study were maintained under anesthesia with halothane in oxygen with intermittent positive-pressure ventilation. A pneumoperitoneum of 15 mmHg or less was achieved with carbon dioxide, and horses were tilted to a 35-degree Trendelenburg position to allow the completion of laparoscopic cryptorchidectomy (n = 13) or ovariectomy (n = 1). Heart rate, mean arterial pressure, and arterial blood gases were recorded at six time intervals throughout the procedure. Results of the study indicated a pH that decreased and partial pressure of carbon dioxide (PaCO2) and mean arterial pressure that increased over time and differed significantly from baseline during Trendelenburg position. Partial pressure of oxygen (PaO2) was significantly lower than baseline after assumption of Trendelenburg position and did not improve on return to normal recumbency and abdominal pressure. As body weight increased, pH and PaO2 decreased and PaCO2 increased. We concluded that horses placed in Trendelenburg position have changes that are transient, with the exception of PaO2. Heavier horses have a greater change in pH, PaCO2, and PaO2 than lighter horses during abdominal insufflation and Trendelenburg position. The changes incurred during CO2 abdominal insufflation and Trendelenburg position are transient, with the exception of a decreased PaO2. Heavy horses undergoing abdominal insufflation and Trendelenburg position should be closely monitored for critical cardiopulmonary values.  相似文献   
992.
应用红细胞促淋巴细胞转化和促NK细胞活性试验,对不同生理发育时期日本大耳白兔红细胞调控淋巴细胞和NK细胞活性进行研究。结果表明:青年组日本大耳白兔红细胞调控淋巴细胞能力明显高于幼年兔和老年兔(P〈0.01);老年组红细胞调控NK活性能力明显高于青年组和幼年组(P〈0.01),青年组高于幼年组(P〈0.01)。日本大耳白兔红细胞调控淋巴细胞能力在青年时期达到了高峰.随后逐渐降低:而红细胞调控NK活性随年龄增长而显著增强,这提示老年兔的免疫活性细胞较多地处于预激活状态,并对刺激显示良好的免疫应答能力。  相似文献   
993.
This study which involved 140 Holstein and Montbeliard was carried out in the periurban area of Dakar with the aim to establish the relationship between ketosis, milk production and biochemical blood metabolites. The results showed that ketosis is a real problem in periurban farms around the city of Dakar with high proportions of 33.57% for subclinical ketosis and 6.43% for clinical ketosis. In their second month of milking, cows with subclinical ketosis had a decrease of 12.4 and 15.,6% in milk yield respectively for Montbeliard and Holstein, whereas cows with clinical ketosis had a decrease of 18.6 and 26%. Ketogenic cows (subclinical and clinical) have significantly lower average levels of blood glucose (p<0.05) and significantly higher average levels of blood urea (p<0.05) than cows with normal blood beta-Hydroxy Butyrate (BbHB) levels. Also, from one farm to another, significant difference was recorded with concentration of total proteins and globulin, calcium and magnesium.  相似文献   
994.
We studied the effects of storage time and temperature of clotted whole blood on the amounts of 17 analytes in bovine blood serum. Serum separated after blood was allowed to stand for 2, 4, 6, 12 and 24h at room temperature or on ice. Results obtained for phosphorous, magnesium, urea, cholesterol, beta-hydroxybutyrate (BHBA), triglyceride, albumin, total protein and gamma-glutamyletransferase (GGT) were not influenced by storage at room temperature or on ice for as long as 24h. Duration of the clotted whole blood storage had a significant effect on calcium, glucose concentrations, creatine kinase (CK) and aspartate aminotransferase (AST) activities and temperature had a significant effect on glucose, non-esterified fatty acids, CK and bilirubin concentrations.  相似文献   
995.
夏季磁处理水对产蛋鸡的影响   总被引:2,自引:0,他引:2  
本试验先后两次在夏季级300日龄左右的产蛋鸡喂饮了利用感应强度为2400高斯的磁水器制备的磁处理水,并观察了磁处理水对蛋鸡生产性能的影响,并测试了几项与产蛋性能有关血液指标。试验结果表明,磁处理水在夏季对产蛋鸡的生产性能具有良好的促进作用,而且对血液指标也有影响。  相似文献   
996.
在大气CO2体积分数为700×10-6条件下,对油桐和烟草的光合CO2同化速率、光呼吸18O2吸收速率、光合色素、叶的脂类和脂肪酸组成等进行了比较分析.结果表明:大气CO2体积分数为700×10-6时油桐和烟草的光合速率有所增加,并抑制光呼吸18O2的吸收,但是,油桐对CO2浓度升高比烟草敏感,它的光合速率在700×10-6CO2时增加了2倍,而光呼吸18O2吸收则完全消失;油桐在700×10-6CO2下生长,光合色素合成量增加较多,其中叶绿素b及类胡罗卜素等属于捕光色素系统的色素增加尤其明显,叶绿素a/b值显著下降,在同样条件下,烟草的叶绿素含量还略有减少,类胡罗卜素含量则明显减少;高浓度CO2影响这两种植物叶的脂类和脂肪酸的组成,700×10-6CO2下生长的这两种植物叶的饱和脂肪酸和磷脂含量有所增加,但油桐叶的糖脂含量有所下降,烟草的糖脂含量则不受CO2浓度升高的影响.  相似文献   
997.
Five mixed-breed dogs underwent splenic sequestration scintigraphy following intravenous injection of 647.5 to 740 MBq (17.5–20 mCi) of 99mTechnetium labeled autologous red blood cells (RBCs) that had been chemically denatured using two μg of stannous chloride. Left lateral dynamic images were obtained for 20 minutes after injection. Regions of interest (ROI) were drawn around the splenic body and ventral extremity, ventral liver and caudal abdominal great vessels and time activity curves created. Count density information was obtained and uptake ratios were calculated for the spleen ROI/vessel ROI, liver ROI/vessel ROI and spleen ROI/liver ROI at 1, 2.5, 5, 10, 15 and 20 minutes after injection. Two additional studies using different RBC denaturing procedures were done in four of the five dogs. In the second study, the stannous chloride level was doubled to 4.0 μg, while in the third study, the RBCs were denatured by addition of 2.0 μg of stannous chloride and heating at 49°C for 15 minutes. Progressive splenic uptake of denatured RBCs was seen in all dogs during the first 15 to 20 minutes of each study, no matter which denaturing technique was utilized. Significant increases in the spleen ROI:/vessel ROI and spleen ROI:liver ROI ratios were obtained at 5, 10, 15 and 20 minutes when compared to the 1 minute values for each of the labeling techniques. A significant difference was not identified between the three ratios at 15 minutes between the three labeling techniques. There was a trend of increasing values for each ratio where 2.0 μg of stannous chloride technique being the lowest, 4.0 μg of stannous chloride having an intermediate value and the heated technique had the highest values. The heating technique resulted in higher liver activity and increased variability of the mean liver ROI/vessel ROI ratios at all times (1, 2.5, 5,10, and 15 minutes). Using a non-linear least squares regression analysis, a double exponential equation fit the spleen ROI/vessel ROI and spleen ROI/liver ROI ratios for all three labeling techniques. Imaging of the spleen using all three techniques was acceptable, and a persistent blood pool image would allow for vascular imaging and cardiac gated studies 30 minutes after injection of the denatured, labeled autologous red blood cells. Veterinary Radiology & Ultrasound, Vol. 36, No. I, 1995, pp 57–63.  相似文献   
998.
以克新 1号和夏坡蒂原种为材料 ,通过田间试验和室内分析测定 ,对生育期间马铃薯块茎还原糖含量的变化与各器官含磷量的关系进行了初步研究。结果表明 :马铃薯块茎中还原糖含量随生育进程逐渐减少 ;品种之间各器官含P量与块茎还原糖含量呈显著负相关 ;增施磷肥可显著提高各器官含磷量 ,从而有利于块茎还原糖含量的降低  相似文献   
999.
热变性法提纯猪血SOD最适条件研究   总被引:5,自引:0,他引:5  
采用热变性法,研究不同的温度和不同的处理时间对提纯猪血中SOD的影响.结果表明,随着温度的升高和处理时间的延长,酶活性和杂蛋白均呈下降趋势.提纯猪血SOD的最适热变性温度为55 ℃,变性时间为15 min.  相似文献   
1000.
以Ross父母代肉仔鸡为对象,研究了日粮中添加牛磺酸对肝中矿物元素含量及血浆中牛磺酸水平的影响。结果表明,饲料中添加0.1%的牛磺酸,可使6日龄肉仔鸡肝中铁、铜、锰、锌含量分别高于对照组28.72%、43.93%、35.61%、60.16%;14日龄时肝中铜、锰、锌分别显著高于对照组25%、33%、38.5%;21日龄时,牛磺酸对肝中矿物元素含量无显著影响。0~14日龄肉仔鸡血浆中牛磺酸含量呈上升趋势(76.76~128.79mg/L),饲料中添加0.1%的牛磺酸可使血浆中牛磺酸水平显著提高;14日龄后,饲料中添加牛磺酸对血浆中牛磺酸水平无显著影响。  相似文献   
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