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81.
82.
Physiologic measurements in nonhuman primates usually are collected from animals that are chemically or physically restrained. Both types of restraint may affect the parameters measured, and those effects can vary with age. Heart rate, respiratory rate, oxygen saturation, expired CO2, blood pressure, temperature, blood glucose, hematocrit, and venous blood gasses were measured in rhesus monkeys that were either infused intravenously with ketamine for 24 h or were cage-housed and physically restrained for sample collection. The subjects were pregnant monkeys at gestational day 120 to 123, infants 5 to 6 d old, and infants 35 to 37 d old. Heart rate and blood pressure were lower in ketamine-treated monkeys than physically restrained monkeys. Heart rate was higher in infants than adults, whereas blood pressure was lower in infants. Respiratory rate was higher in infants than adults and higher in physically restrained infants than ketamine-sedated infants but was not affected by ketamine in pregnant adults. Hematocrit was decreased in older infants. In summary, both physical restraint and ketamine sedation altered several physiologic parameters in pregnant and infant rhesus macaques. Investigators should consider these effects when designing experiments and evaluating experimental outcomes in monkeys.  相似文献   
83.
Postoperative deep vein thrombosis in the Taiwanese Chinese population   总被引:1,自引:0,他引:1  
Reports of the incidence of postoperative deep vein thrombosis in the Chinese population of Taiwan are few in the literature. Over a 3 year period, the fibrinogen degradation products test, the pulse volume recorder, and venography were used to study 220 patients undergoing major operations at the Veterans General Hospital in Taipei, Taiwan. Deep vein thrombosis was found in 17 patients (7.7 percent). A comparison of the three diagnostic methods showed that the sensitivities of the fibrinogen degradation products test and the pulse volume recorder were 56.3 percent and 93.7 percent, respectively; the specificities, 97.4 percent and 95.7 percent, respectively; and the accuracies, 85.5 percent and 95.5 percent, respectively. These results support the combined use of the fibrinogen degradation products test and the pulse volume recorder for screening and diagnosing deep vein thrombosis.  相似文献   
84.
We have examined polyol pathway kinetics in the lenses of rats made diabetic with streptozotocin. At up to 11 days after diabetes induction, the lenses were isolated and subjected to 'pulse-chase' studies: the lenses were incubated with [13C]glucose and lens metabolism followed by [13C]nuclear magnetic resonance (NMR) spectroscopy. Proton NMR spectroscopy was also performed to measure the hexose monophosphate shunt (HMPS) activity. The results showed that (1) the activity of aldose reductase increased initially and decreased after 11 days of diabetes; (2) the fructose pool increased initially but started to decline after 3 days; (3) the HMPS activity increased nearly 40% immediately after diabetes induction; and (4) the turnover rates of glucose, alpha-glycerophosphate (GP), lactate, sorbitol, and fructose were 80.8 +/- 2.6, 10.1 +/- 1.4, 47.7 +/- 3.7, 7.9 +/- 0.9 and 5.2 +/- 2.2 nmol hr-1 lens-1 (34 mg wet weight lens-1), respectively. Up to 35% of lactate appeared to derive from the polyol pathway. Further, GP was rapidly metabolized, although its fate is currently unknown. These results reveal a far more complex pattern of glucose metabolism in the diabetic lens than that in lenses incubated in high glucose.  相似文献   
85.
High speed colour cinematography at 400 frames per second was used to photograph both single and train burst Nd/YAG laser applications in ox eyes at threshold energy levels. Measurements of the extent and speed of particle scatter and tissue distortion from the acoustic transient were made from a sequential freeze frame analysis of the films. Particles were observed to travel over 8 mm from the site of Nd/YAG application 20 milliseconds after a single pulse at initial speeds in excess of 20 km/h. The use of train bursts of pulses was seen to increase the number of particles scattered and project the wavefront of particles further from the point of laser application.  相似文献   
86.
OBJECTIVE: To investigate the feasibility of intracoronary application of endothelial progenitor cells and the subsequent distribution within the heart. METHODS: Endothelial progenitors cells (EPCs) cultured from rat bone marrow were identified by double-positive staining with Dil-Ac-LDL and BS1-lectin. Twenty-four hours before cell transplantation, EPCs were labeled with 5-bromo-2'-deoxyuridine (BrdU). Cells (5 x 10(5) in 250-microl medium) were injected into healthy rats, either as intracoronary application (n=11) or as intramyocardial injection (n = 6). At 15 min or 3 days posttransplantation, hearts as well as other organs (lung, liver, kidney, and spleen) were collected and processed for subsequent BrdU immunohistochemistry. The number of BrdU-positive cells per tissue area was counted. RESULTS: Compared to intramyocardial injection, intracoronary administration resulted in more than twice as much positive cells in the heart (P < .05), with no local differences within the heart. Whereas after 15 min, EPCs were equally distributed in all examined organs (except for the spleen), cells that were still present after 3 days, approximately 10%, were selectively restricted to the heart. CONCLUSIONS: Our data indicate that the intracoronary application provides a promising technique for EPC transplantation in the rat heart.  相似文献   
87.
We hypothesized that sensory input from the moving leg induces presynaptic inhibition of the soleus H reflex pathway in the contralateral stationary leg. The results showed a crossed inhibition during passive pedalling movement of the leg, which was not removed by low levels of tonic contraction of soleus in the stationary leg. The inhibition was correlated exponentially to the rate of the movement (R2=0.934, P<0.05) and was not dependent on the quadrants through which the moving leg was passing. Static flexion of the stationary leg caused ipsilateral inhibition of the reflexes (t=5.590, P<0.05), independent of the orientations of the other leg. We concluded that sensory inflow from the moving leg induces presynaptic inhibition in the stationary leg, that a complex transformation of the sensory input in the spinal cord or brain underlies the tonic crossed inhibition and phasic ipsilateral inhibition, and that descending motor commands exert a powerful control over these sensorimotor modulatory mechanisms.  相似文献   
88.
微波氚标记法与化合物结构的关系   总被引:1,自引:1,他引:0  
本文报道了应用微波氚标记了许多不同类型的化合物,这些化合物的放射比度与结构紧密相关,对于在相同条件下研究不同化合物的标记比度提供了一些参考数据。  相似文献   
89.
采用微波炉中的谐振场和外辐射天线的平面波对冻存在-196℃的活细胞进行复温试验。结果表明:谐振场加温迅速但极不均匀,造成细胞大量死亡。平面电磁波微波泄漏大,效率低,加温时间过长,不能应用。本文阐述了微波对超低温细胞复温的可能性和现有微波仪不宜进行细胞复温的原因,并提出改进设计的建议。  相似文献   
90.
用酶联亲合组化法对46例肺肿瘤细胞进行了雌激素受体(ER)和孕激素受体(PR)检测。同时测定14例肺瘤肿患者血清雌二醇(E_2)浓度。结果表明:肺肿瘤 ER 阳性率为36.9%,PR 阳性率为13.0%。阳性率与性别、病理类型及血浆 E_2浓度无关。认为肺癌的发生发展可能与雌激素有依赖关系,提示内分泌疗法可能会成为原发肺肿瘤的一种治疗手段。另用 ABC 法对上述46例肺肿瘤中的29例进行了花生凝集素受体(PNA-R)和麦胚凝集素受体(WGA-R)的检测,PNA-R 在腺癌大都为顶浆型分布,鳞癌和透明细胞癌则多为胞膜型分布。结果提示 PNA-R 是肺癌分化过程中的一种标志,对肺癌分型、预后判断有一定协助作用。同时将29例肺肿瘤 PNA-R 与 ER 状况作对比研究,探讨了二者之间的相关性及可能的发生机制。  相似文献   
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