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991.
本文介绍一种简化的行之有效的去大鼠大脑方法。与传统方法相比,本法不需结扎颈总动脉或其分支,可简化手术程序,缩短手术时间,避免因手术操作对颈动脉窦区参与呼吸循环功能反射性调节的重要感受器及其传入神经的可能损伤。用此法去大脑后,动物的呼吸频率、心率、动脉血压等可稳定10小时以上,并能成功地进行延髓细胞内记录和标记。本法可用于研究脑干调控功能的急性动物实验。  相似文献   
992.
We did a prospective study of 70 adults with chronic subdural hematomas.We looked at the correlation between some aetiological, clinical, and radiological factors and outcome.The present analysis found a significant positive correlation of cephalea, isodense aspect of the hematoma at CT scan, and pulsatance of the encephalon at surgery to good clinical outcome.Viceversa, alcoholism and intracranial hypotension associated with postoperative pneumocephalus are factors usually correlated with a negative clinical course.  相似文献   
993.
Hepatic spiral CT: reduction of dose of intravenous contrast material   总被引:13,自引:0,他引:13  
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994.
Resistance of tumour-bearing mice to a second tumour challenge, that is concomitant resistance, was evaluated in euthymic and nude mice using nine tumours with widely different degrees of immunogenicity. Two temporally separate peaks of concomitant resistance were detected during tumour development. The first one was exhibited only by small immunogenic tumours; it was tumour specific and mediated by classical immunological T-cell-dependent mechanisms. The second peak was shared by both immunogenic and non-immunogenic large tumours; it was non-specific, thymus independent and correlated with the activity of a serum factor (neither antibody nor complement) that inhibited the in vitro proliferation of tumour cells. This factor was eluted from a Sephadex G-15 column at fractions corresponding to a molecular weight of approximately 1000 Da and it was recovered from a high-performance liquid chromatography column in one peak presenting maximum absorption at 215 and 266 nm. The data presented in this paper suggest for the first time, to our knowledge, that in spite of the differences between immunogenic and non-immunogenic tumours, a common serum-mediated mechanism seems to underlie the concomitant resistance induced by both types of tumours at late stages of tumour development.  相似文献   
995.
996.
Summary— In recent years, two key concepts having numerous interrelationships were advanced for the understanding of various cardiovascular diseases: the “endothelial dysfunction” and the “arterial remodelling”. Both endothelial dysfunction and arterial remodelling occur in various pathologies including essential hypertension, heart failure, atherosclerosis, restenosis after angioplasty, and pulmonary hypertension, and have modified the therapeutic approach by offering new pharmacological targets: specific receptors not only at the site of the vascular smooth muscle cells but also on the endothelial cells, growth factors that stimulate proliferation of smooth muscle, and receptors and enzymes of the extra-cellular matrix. Among the various substances under research, the present review will discuss angiotensin II receptor antagonists, endothelin receptor antagonists, nitrates-NO donors, potassium channel activators, and substances interfering with proteoglycans and other components of the extra-cellular matrix.  相似文献   
997.
998.
Orbital cellulitis is a rare, serious and potentially fatal condition, usually associated with trauma to the eyelids, external ocular infection, upper respiratory tract infection and, especially, sinusitis. It is distinct from the more common periorbital cellulitis because it involves all contents of the orbit and may threaten both the vision and the life of the patient. It occurs with greater frequency in children. We report the case of a 34-year-old woman with severe facial and right periorbital cellulitis who rapidly developed orbital involvement, as shown by computed tomography. Apart from a bilateral retroauricular dermatitis, present for several years, the woman had been always healthy. Systemic antibiotics were started without delay and she recovered very well, with no ocular sequelae. This case illustrates that a subset of bacterial skin infections is becoming more aggressive and should be recognized and treated early.  相似文献   
999.
1000.
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