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371.
The accuracy of thermodilution for measuring flow rates of 10–40 L/min was evaluated using a commercially available thermodilution cardiac output computer in an in vitro model. Water (36.5–37.5°C) was directed through a mixing chamber via a constant flow pump. Thermodilution estimates of flow using four different volumes (10, 20, 30, 40 ml) of iced water injectate were compared to simultaneous measurements of timed samples of effluent from the mixing chamber. Injectate volume had a significant impact on the accuracy of thermodilution estimation (p < 0.05). Thermodilution overestimated measured flow when 10 and 20 ml of injectate were used to determine flow rates < 20 L/min but underestimated flow when injectate volumes of 30 and 40 ml were used, or when measured flow was > 25 L/min. The discrepancy between thermodilution flow and measured flow increased as rate of fluid flow increased.  相似文献   
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373.
Thirty-eight dogs with hip dysplasia were studied to evaluate the use of gold wire implants at acupuncture points around the hip joints. They were assigned at random into two groups of 19. In the treated group, gold wire was inserted through hypodermic needles at electrically found acupuncture points around both hips. In the control group, the areas were prepared in the same way but had only the skin pierced at sites which were not acupuncture points, with a needle of the same size as that used in the treated group. Over a period of six months the dogs were studied repeatedly by two veterinarians and by the dogs' owners who were unaware of the treatments the dogs had received; they assessed the dogs' locomotion, hip function and signs of pain. Radiographs were taken at the beginning and end of the study. Although the data collected from both groups by the veterinarians and the owners showed a significant improvement of locomotion and reduction in signs of pain (P=0.036 for the veterinary evaluation and locomotion and P=0.0001 and P=0.0034 for the owners' evaluation of locomotion and pain, respectively), there were no statistically significant differences between the treated and control groups (P=0.19 and P=0.41, P=0.24, respectively).  相似文献   
374.
The effects of lipopolysaccharide ( Escherichia coli , O55:B5), administered 18 h after ovulation in the second oestrus after weaning on the hormonal profiles in 14 Swedish cross-bred (Landrace × Yorkshire) multiparous sows were studied. The endotoxin group (E-group) sows were administered with 300 ng/kg of lipopolysaccharide (LPS) whereas the control group (C-group) sows were administered 5 ml of saline intravenously via an indwelling jugular cannula. Blood samples for hormonal analyses were collected from all sows until slaughter. In the E-group, progesterone, cortisol and prostaglandin F metabolite levels increased significantly (p < 0.05) following LPS compared with the C-group. It can be concluded from this study that apart from elevating cortisol and prostaglandin F metabolite, LPS also elevates progesterone levels.  相似文献   
375.
Cardio pulmonary embarrassment was induced with thiopentone sodium in 35 healthy adult donkeys divided in to seven groups of five animals. “To effect” anaesthetic dose was (12.72 ± 0.69 mg/kg) which caused transient hypotension, tachycardia and hypoxemia. A stable fall in MAP 1. 6.77 ± 0.287 Kpa (50.78 ± 2.15 mmHg) and a flat EEG were considered to indicate acute circulatory insufficiency due to thiopentone overdose.  相似文献   
376.
377.
The purpose of this study was to determine whether lingual vanous blood gas samples reflect arterial acid-base gas status in anethetized dogs. Heparinized blood samples were drawn simultaneously from the lingual vein and a peripheral artery in 50 anestheized dogs that were clinical surgical patients, as well as from four experimental dogs in which hemorrahaic shock was being studied. Blood pH, oxygen tension (PO2), and bicarbonate (HCO3-)) from the two sources in clinical patients showed significant liner correlation, although arterial PO2)(PaO2)) tended to be approximately 110mm Hg higher than lingual venous PO2). During hemorrahgic shock, however, PaO2) and PaCO2) were significantly different from lingual venous PO2) and PCO2), Lingula venous blood gas analysis may be useful in assessing acid-base and blood gas status in routline cases, but should not be relied upon in dogs with low cardiac output or poor perfusion.  相似文献   
378.
Canine thyroglobulin (cTg) has been isolated and purified. It has similar electrophoretic patterns as Tg from other mammalian species. The main fraction had a MW of 660,000, whereas also fractions of a MW of approximately 1,300,000 (dimer) and 330,000 (subunit) were present. The iodine content was 0.8 to 1.0 % (w/w). cTg did not cross-react with antibodies against human Tg to a degree that would allow the use of a radioimmunoassay for human Tg for the determination of cTg in serum or plasma. Therefore a polyclonal antiserum was raised against cTg and a homologous radioimmunoassay was developed, which was sensitive (0.4 μg/l) and specific (cross-reactivity in cTg assay of human Tg, goat Tg, T4, T3, and DIT < 0.01 %).

Plasma Tg levels in normal dogs of both sexes and aged 3–15 years amounted to 192 ± 73 μg/l (mean ± SD, n=30). There was no relation between plasma Tg and T4 levels.  相似文献   

379.
380.
荷兰是全世界畜牧业高度发达的国家之一。养猪业也象奶牛业一样发展很好,特别是猪场管理很值得我国养猪同行学习。该国的养猪规模很大,一般都在2000头左右。其养猪业的先进性在于:年头均产胎指数2.3,年头均母猪出栏仔猪23头,胎产活仔数11.8头,受胎率85%,仔猪早期断奶及母猪年更新率为50%。  相似文献   
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