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991.
用吐温80-乙醚(TE)法、蔗糖-丙酮(SA)法、丙酮-乙醚(AE)法分别从肾综合征出血热病毒(HFRSV)感染的Vero-E6细胞培养和乳小白鼠脑组织中制备病毒血凝素(HAN),定量对比证明其制备效果,结果无明显差异。粗制HAN经高压液相色谱(EPLC)纯化,有4个洗脱峰,血凝活性物质存在于峰1。纯化HAN在SDS-PAGE中呈单一区带,分子量56.6KD,HAN相对含量79.6%。纯化HAN在蔗糖密度梯度液中有一条1.15~1.16g/cm3的沉淀,粗制HAN有3条沉淀。电镜观察纯化HAN中为大小相等的球状颗粒。粗制HAN的高密度沉淀中可见到病样颗粒。对几种常用消毒剂、氧化剂、去垢剂对HAN的灭活作用做了实验对比观察。 相似文献
992.
本研究通过整体及离体灌流实验观察到重庆冠脉狭窄时,犬冠脉流量(CBF),平均动脉压(MAP)明显减小,而心率(HR)则增加。狭窄30min后由冠状动脉注射降钙素基因相关肽(CGRP)0.3μg/kg后,CBF、MAP和HR可恢复正常水平。同时,缺血犬的离体冠状动脉对CGRP的反应也出现改变。大冠脉舒张反应明显降低,而小冠脉的舒张反应与正常相比,无明显改变,这可能与缺血后大冠脉的内皮细胞容易损伤有关。同时也提示:急性心肌缺血时,冠脉流量的减少,主要由于小冠状动脉收缩所致。 相似文献
993.
Summary The case of a 75-year-old man with Guillain-Barré syndrome is presented. By means of transcranial electrical stimulation and epidural recording at the spinal level L2-3, distinct potentials with a latency of 21ms were obtained when the patient was tetraplegic. At the same time electromyographic responses of the thenar and anterior tibial muscles were absent following both transcranial and peripheral nerve stimulation. The patient recovered partially within 4 weeks. It is concluded that epidurally recorded motor evoked responses allow electrophysiological assessment of the descending pathways even in severe cases of Guillain-Barré syndrome and might contribute to a more accurate prediction of outcome. 相似文献
994.
Seven middle-aged men with manifest type II diabetes mellitus underwent an endurance training programme for 10–15 weeks. The maximal aerobic capacity, as well as the endurance capacity, was improved by 10% (p<0.05). The intramuscular glycogen store increased by more than 80% (p<0.05) from 350 μmol/g dw (dry weight), and the activities of citrate synthase and 3-hydroxy-acyl-CoA dehydrogenase increased by more than 50% (p<0.05) and 30% (p<0.05). The activity of glycogen synthase was decreased by approximately 20% (p<0.05), whereas lactate dehydrogenase remained unchanged. Capillaries/fibre and fibre area increased by more than 50% (p<0.05) and 30% (p<0.05) leaving the area of supply constant. Training did not influence fasting blood lipids and glucose, glycosylated hemoglobin, oral glucose tolerance, and insulin response to an oral glucose load measured 72 hours post-exercise. It is concluded that patients with manifest type II diabetes, as normoglycaemic individuals, adapt to physical training. However, no persistent effect on glucohomeostasis and lipaemia is produced by short-term training in the diabetic patients. 相似文献
995.
The superior sagittal sinus (SSS) and the trigeminal ganglion (Vg) of anesthetized cats were stimulated electrically and field potentials in the upper cervical spinal cord and regional cerebral blood flow were recorded. Stimulation of the entire ganglion produced smaller field potential changes in two regions (medioventral area (MVA); dorsolateral area (DLA] of the upper spinal cord than did stimulation of the sagittal sinus (Vg/SSS response ratio = 17% for the MVA and 48% for the DLA). Stimulation of the trigeminal ganglion increased blood flow in only the frontal and parietal cortices (+93% and +33%), whereas stimulation of the sinus produced both larger changes in these areas (+137% and +139%) and also produced changes in regional cerebral blood flow in the thalamus (+122%). 相似文献
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W L de Kort M A Verschoor A A Wibowo J J van Hemmen 《American journal of industrial medicine》1987,11(2):145-156
A group of workers, occupationally exposed to lead and cadmium compounds (n = 53), was compared to a group of workers not exposed to these metals (n = 52). The average values of systolic, diastolic, and mean blood pressure were found to be higher in the exposed group (p less than 0.05). In contrast with the correlation between CdU and blood pressure, the correlation between PbB and systolic and mean blood pressure remained statistically significant after controlling for age and pulse rate (r = 0.22, p less than 0.05). The prevalence of potential hypertension (defined as systolic blood pressure greater than or equal to 160 mm Hg and/or diastolic blood pressure greater than or equal to 95 mm Hg and/or under treatment for hypertension) was higher in the exposed group, but the observed relative risk was not statistically significant: relative risk = 1.91 (95% confidence limits, 0.90-4.05). Furthermore, a significant correlation between PbB and Hgb (r = -0.28, p = 0.004) was observed. Differences in kidney function, as assessed in this study, were not detected. 相似文献