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81.
Effects of stimulation of brainstem sites on hemodynamics and plasma catecholamine levels were assessed in cats under chloralose-urethane anesthesia. Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection. Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in caval blood above the adrenal veins. Electrical stimulation of the DM and VLM produced increases in blood pressure and in plasma NE and EPI levels that were enhanced after acute vagotomies. The NE and EPI responses were attenuated after acute, bilateral adrenalectomies, confirming augmented adrenomedullary secretion, whereas the pressor responses were intact. Injection of sodium glutamate into the same pressor regions of the DM or VLM also produced pressor responses and elevated plasma catecholamine levels, indicating that the responses resulted from activation of neuronal perikarya. Stimulation of the PRN attenuated pressor and catecholamine responses during stimulation of the DM and VLM. The results indicate that pressor responses during stimulation of the DM and VLM are due at least partly to activation of perikarya in these regions, are associated with but not dependent on adrenomedullary activation, and are enhanced after vagotomy; and that neurons of the PRN exert inhibitory modulation of the pressor and adrenomedullary responses during stimulation of VLM and DM.  相似文献   
82.
M Ma  H Hu  F Kutlar  J B Wilson  T H Huisman 《Hemoglobin》1987,11(5):473-479
A slow-moving gamma chain variant was discovered in the cord blood of an infant born to parents of the Han nationality from Jiangsu. The variant, which migrated electrophoretically at alkaline pH between Hb A and Hb D, was characterized by an Asp----His substitution at gamma 73, while residues gamma 75 and gamma 136 were occupied by Ile and Ala, respectively. As the A gamma T-chain was also present, this baby has two types of abnormal gamma-chain. The variant was named Hb F-Xin-Su.  相似文献   
83.
The present paper deals with the susceptibility of common laboratory animals, such as mouse, rat, hamster, jird, rabbit and rhesus monkey, to infection with different isolates of Schistosoma japonicum in the mainland of China under laboratory conditions. With the exception of the rat, all the animals under study were permissive hosts for different isolates though their worm recovery rates varied. The mean body length of pair-worms of the Yunnan isolate was considerably smaller than that of the Anhui, Hubei, Guangxi and Sichuan isolates, and the percentage of male specimens with 7 testes in the Yunnan isolate was also significantly less than that in the other 4 isolates. Judging from the egg index (width/length x 100), the eggs of the Sichuan isolate were broad and short in shape, giving a high index; those of Guangxi and Hubei isolates were oblong, giving the lowest index; the other two isolates from Yunnan and Anhui, lay between these two extremes. The mean prepatent periods were longer in mice, hamsters and rhesus monkeys infected with Yunnan and Guangxi isolates, than those with Sichuan isolate. A dendrogram of the 5 isolates of S. japonicum was constructed on the basis of similarity coefficients by means of fuzzy cluster analysis on the biological characters mentioned above. Our results provide evidence of the existence of different strains of S. japonicum in the mainland of China as shown by comparative studies of their characteristics in the final hosts.  相似文献   
84.
目的 了解绥芬河公路口岸附近EHF亚在鼠类中的流行动态。方法 对鼠类进行EHF IgG抗体监测。结果 检测142只、5种鼠类的血样,检出EHF IgG抗体阳性29例,阳性率为20.42%。其中黑线姬鼠的移抗体IgG抗体阳性率较高,为30.95%。结论 EHF宿主是属于多源性动物宿主,而黑线姬鼠是主要贮存宿主和传染源,提示我们要注意防鼠、灭鼠。  相似文献   
85.
高血压病人药物治疗期间动态血压变化   总被引:49,自引:0,他引:49  
目的评价高血压病人药物治疗期间24h动态血压变化。方法26例住院的高血压病人经药物治疗4周连续3d随测血压,血压正常后进入本研究。治疗前后进行24h动态血压监测。结果患者随测血压(8~9AM,3~4PM)血压恢复到正常水平,但动态血压显示在一段时间内(6~8AM,6~11PM)平均收缩和舒张压仍明显高于正常人平均水平(P<0.01),而该时间段易被临床医生忽视。结论随测血压不能实际全面反映高血压病人药物治疗的疗效,24h动态血压的监测可以正确评价高血压病人药物治疗的效果并根据高血压分布的时间来调整降压药的种类和剂量。  相似文献   
86.
肺炎性假瘤(附52例报告)   总被引:4,自引:1,他引:3  
目的:分析肺炎性假瘤的临床病理特点,并探讨其诊断问题,方法:回顾性分析52例肺炎性假瘤的临床病理资料。结果:男女发病比为2.25:1,平均年龄50.6岁,平均病程10.8个月,临床主要表现为咳嗽或咳痰,痰中带血或咯血,胸痛或背痛;影像检查见肿块位于肺周边部,单发,圆形或类圆形,病理检查肿块最大平均直径为3.9cm,见于各肺多于左肺,双上肺多于双下肺,44.2%同侧肺门淋巴结因反应性增生而肿大;经系统抗炎,抗结核治疗,肺肿块影均无改变,手术切除可治愈,结论:肺炎性假瘤有其特点,可与肺癌、肺结核、肺炎相区别;确诊仍需病理活检;CT或超声引导经皮活检值得推广,并应重视电视胸腔腔镜在诊治中的作用。  相似文献   
87.
应用高压氧治疗尺桡神经损伤修复术后11例,与同期单纯手术修复14例相比,优良率明显提高,二组间有显著差异。P<0.05,提示高压氧对尺桡神经损伤的修复有促进作用  相似文献   
88.
Chronic lead exposure may cause hypertension in normotensive rats. This hypertensinogenic effect has been attributed to perturbations in the renin-angiotensin axis, the contractile response of the vascular smooth muscle, or the intracellular Ca2+ homeostasis as a consequence of the inhibition of Na(+)-K(+)-ATPase activity. In this study we examined the short-term effect of lead exposure on blood pressure, plasma renin activity, vascular contractility, and renal Na(+)-K(+)-ATPase activity and abundance in the spontaneously hypertensive rat. Our data indicate that modest lead exposure caused blood pressure elevation within two weeks in this rat strain that is genetically susceptible to the development of hypertension. This rapid blood pressure-elevating effect did not appear to depend on the mechanisms described in hypertension associated with more chronic lead exposure listed above. This acute model provides an additional approach to the study of lead-induced hypertension.  相似文献   
89.
为探索天然超氧化物岐化酶(SOD)岐化超氧离子的机理,及用于临床的可能性,我们合成了乳酸、柠檬酸和酒石酸的锰(Ⅱ)配合物作为Mn-SOD的模拟物,用光照法测定了它们的活性,得到了有意义的结果:锰配合物作为Mn-SOD的模拟物,有肯定的活性,其中以乳酸锰配合物活性最高。  相似文献   
90.
P C Hu 《中华结核和呼吸杂志》1992,15(3):163-4, 191-2
In our study, we observed that (1) High RCIA were discovered in these two groups. (2) In the group of pulmonary tuberculosis, the C3b receptor activities remained no change after antituberculous therapy, but the amounts of immune complexes bearing on RBC decreased. In the patients with the high RCIA, CIC was discharged rapidly and the lesions of tissue produced by CIC were prevented. In the patients with silicotuberculosis, both silica and tuberculous bacilli may act as immune adjuvant and enhance the hypersensitivity. So the C3b receptor activities were higher in silicotuberculosis patients.  相似文献   
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