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961.
Activating effect of substance P on nerve tissue in culture 总被引:1,自引:0,他引:1
The effect of substance P on organotypic culture of rat sympathetic ganglia and spinal cord was studied. Substance P was able to stimulate the fibre outgrowth from explant, to increase the numbers of glial and fibroblasttypic cells in ganglia growth zone. The effect was observed in the range from 10(-5) to 10(-12) M (for sympathetic ganglia) and from 10(-5) to 10(-14) M (for spinal cord culture). It is suggested that substance P can be used as a nonspecific growth factor for peripheral and central nervous tissue. 相似文献
962.
We reviewed 86 consecutive patients undergoing elective carotid endarterectomy to determine whether preoperative clinical and angiographic data could be used to predict the risk of intraoperative cerebral ischemia during carotid occlusion. Electroencephalographic (EEG) monitoring with on-line Berg-Fourier transformation was carried out in all patients. A total of 32 patients (37.2%) underwent intraoperative shunting. Of these, 13 had no EEG changes but underwent shunting because of the surgeon's preference, while 19 patients underwent shunting because of EEG changes consistent with cerebral ischemia. There was one permanent (1.2%) and one transient (1.2%) neurologic deficit. Angiographic findings, clinical histories, and intraoperative EEGs were retrospectively reviewed to determine which risk factors best predicted the occurrence of intraoperative cerebral ischemia. Stroke within six weeks increased the risk of intraoperative cerebral ischemia 20-fold. Intracranial disease and contralateral carotid stenosis increased the risk of ischemia 17-fold and 16-fold, respectively. Statistical summation of all risk factors yielded a probability equation for EEG change that accurately quantitated pre-operative risk. Prospective application of this probability equation may simplify operative decision making if EEG monitoring is not available. 相似文献
963.
A V Pinto V F Ferreira R S Capella B Gilbert M C Pinto J S da Silva 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(4):609-610
Accidental transmission of Chagas disease to man by blood transfusion is a serious problem in Latin America. This paper describes the testing of several naphthoquinones, some of which were active against blood trypomastigotes in vitro at 4 degrees C and might therefore warrant further study for preventing transmission of Chagas disease by blood transfusion. 相似文献
964.
965.
966.
967.
Single units were recorded using extracellular glass microelectrodes in all laminae of the superior colliculus of the rat under halothane nitrous oxide anaesthesia. Fifty-one units were encountered which responded to a low intensity mechanical stimulus applied to a contralateral or bilateral field located in the oral sphere (intraoral 11, perioral 16), on the face (29) or on the rest of the body (21). Sixteen units responded to a jaw movement. Sixty-one cells were recorded which were preferentially (10) or only (51) activated (30) or inhibited (21) by noxious stimuli. Contralateral or bilateral mechanoreceptive fields located in intraoral (34) and perioral (35) areas were frequent. There is therefore a high incidence of the nociceptive representation of the mouth in the superior colliculus. The other functional properties of the nociceptive units were similar to those reported in other studies. From the subsequent histological localization of the recorded units, it appeared that the nociceptive projections from the intraoral and perioral regions to the superior colliculus reach the lateral part of the intermediate and deep layers of the superior colliculus. 相似文献
968.
Respiratory symptoms and bronchial reactivity: identification of a syndrome and its relation to asthma 总被引:17,自引:0,他引:17
A K Mortagy J B Howell W E Waters 《British medical journal (Clinical research ed.)》1986,293(6546):525-529
Two postal questionnaire surveys were carried out among the adult population of Southampton aimed at clarifying the diagnostic criteria for asthma (study 1) and at testing the validity of symptoms so identified as diagnostic of bronchial hyper-reactivity (study 2). The questionnaires asked about respiratory symptoms and included three questions thought likely to disclose increased bronchial reactivity. Laboratory measurements on subsamples of respondents included spirometry and bronchial challenge with increasing doses of histamine till a concentration was reached provoking a fall of more than 20% (PC greater than 20) in forced expiratory volume in one second. In the first study no normal subject (that is, one who did not report shortness of breath or wheezing on the questionnaire) had a PC greater than 20 below 0.5 g/l. Of 51 subjects who reported shortness of breath or wheezing, or both, nine had a cluster of abnormalities consisting of one or more symptoms of bronchial irritability, nocturnal dyspnoea, and prolonged morning tightness together with PC greater than 20 values of 0.5 g/l or less. These symptoms in conjunction with a low PC greater than 20 were termed the bronchial irritability syndrome. In the second study bronchial challenge confirmed the close association of these symptoms with bronchial hyper-reactivity, all other subjects being less reactive to histamine. Only 27% of subjects with symptoms of the bronchial irritability syndrome had been diagnosed as asthmatic by their general practitioners. The bronchial irritability syndrome is a definable entity for epidemiological study and patient care. 相似文献
969.
B Adelsberg 《Pediatric annals》1987,16(6):477, 480-477, 484
The activities of the complement system encompass cell destruction either directly through the membrane attack complex or indirectly via the effects of inflammation. The effects of complement fragments on immune functioning are just now being elucidated. Recent advances in methodology have allowed recognition of complement deficiencies of both quantitative and structural varieties. Complement activation studies may detect subclinical activation and be useful guideposts for therapeutic intervention. Coupling our new understanding of the mechanisms of complement activation with new technologies to measure this activation may result in the better understanding of the pathology of inflammation and its concurrent immunologic reactions. 相似文献
970.
Trends in cervical cancer in New Zealand 总被引:2,自引:0,他引:2
Analysis of mortality and incidence rates over a 30-year period discloses differing trends in the risk of cervical cancer in older and younger women. Age-specific rates have been declining in older women, but there has been a marked rise in incidence among women under 40. Birth-cohort analyses show declining risks in successive cohorts of women born from late in the last century until the 1930's, except that risks were slightly elevated in the generation who were young adults during the Second World War. The risk of cervical cancer has increased very rapidly in cohorts born since the 1930s. A mathematical model suggests that women born around 1957 may have over three times the risk experienced by women born around 1932. The numbers of New Zealand women developing, and dying from, cervical cancer will increase strikingly over the next few decades unless effective control measures are introduced. 相似文献