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991.
C. W. Pagenkopf J-P. Bourreau C. E. Challice 《Clinical and experimental pharmacology & physiology》1990,17(8):557-565
1. Age-related changes in prejunctional alpha 2-adrenoceptors were examined in the rat vas deferens using pharmacological techniques. 2. B-HT 933 (1 x 10(-8) - 1 x 10(-6) mol/L) caused a concentration-dependent inhibition of isometric contractions (tetrodotoxin-sensitive) induced by stimulation with single field-stimulus pulses, in both the epididymal and prostatic regions of rat vas deferens. The concentration-response curve to B-HT 933 was shifted to the right with age in the prostatic regions of the vas deferens. 3. In high concentrations (10(-6) - 3 x 10(-4) mol/L), B-HT 933 caused concentration-dependent enhancement of the contractile response to stimulation and evoked spontaneous contractile activity. No significant difference in this postjunctional activity occurred with age in either the prostatic or epididymal regions of the vas deferens. 4. Schild analysis revealed no significant differences in pA2 values for the antagonisms of the prejunctional inhibitory effect of B-HT 933 by rauwolscine in either the prostatic or epididymal regions of vas deferens between young and old rats. 5. These results could be interpreted as a decrease in alpha 2-adrenoceptor number with age. The more marked decrease in the prejunctional inhibitor potency of B-HT 933 in prostatic regions of vas deferens with aging may be due to a smaller receptor reserve in this region of the vas deferens. 相似文献
992.
本文应用酶联免疫测定法对广西壮族自治区原发性肝癌高发的扶绥县和低发的阳朔县,进行了黄曲霉毒素B_1及代谢物黄曲霉毒素M_1和原发性肝癌关系的流行病调查。结果发现,原发性肝癌的死亡率与黄曲霉毒素B_1摄入量,晨尿黄曲霉毒素M_1排出量呈明显的正相关。展尿黄曲霉毒素M_1排出量可作为人群接触黄曲霉毒素B_1水平的指标。原发性肝癌死亡率与玉米、花生和花生油的摄入量有关。 相似文献
993.
15例肝癌患者施行外科治疗,12例兼用卡介苗、混合菌苗及干扰素,3例不用免疫治疗为对照。分离患者血单核细胞(MC)与淋巴细胞(LC)及肝枯否细胞(KC),以人肝癌细胞株为靶细胞(TC)。结果:①首次用免疫制剂7d后,MC对TC抑增殖作用及杀伤作用明显高于用药前,3次用药后MC抑TC效应提高至84%,对照组的仍为45%;②首次用药后7d,KC对TC的抑增殖率和杀伤率分别较对照组高0.5倍和1倍;③用免疫制剂后,血T细胞总数及Th数持续升高,T_s则显著下降。研究表明三联免疫制剂可有效地增强患者抗肝癌细胞的免疫功能。 相似文献
994.
Cardiac arrest after isoflurane anaesthesia in a patient with Duchenne''s muscular dystrophy 总被引:4,自引:0,他引:4
An 8-year-old boy known to have Duchenne's muscular dystrophy suffered a cardiac arrest 10 minutes after he regained consciousness after isoflurane anaesthesia for an orchidopexy procedure. Resuscitation was successful 2 hours after the start of external cardiac compression and after correction of hyperkalaemia and the administration of dantrolene. He later developed myoglobinuria elevated creatine kinase and a metabolic and respiratory acidosis. He demonstrated a delayed increase in rectal temperature. 相似文献
995.
996.
Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed. 相似文献
997.
应用单链构象多态性分析多聚酶链反应EB染色法(PCR-SSCP-EB)对40例肺癌组织标本的P53基因序列5~8外显子突变进行分析,同时应用PCR方法检测上述标本及18例肺良性疾病组织标本中HPV16、18型DNA相关序列,旨在分析二者在肺鳞癌发病中的作用及相互关系,并就肺鳞癌与P53基因结构和功能异常的关系进行初步探讨。 相似文献
998.
Ken Igawa Ryuji Maruyama Ichiro Katayama Kiyoshi Nishioka 《The Journal of dermatology》1997,24(5):328-331
A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease. 相似文献
999.
TAMÁS HENICS & DENYS N. WHEATLEY 《International journal of experimental pathology》1997,78(5):343-354
Hep-2, human epithelial carcinoma cells, and human foreskin fibroblasts (FF9 and FF13) were exposed to either an ultrafiltrate (< 50 kD) of human sera or the weak base, procaine hydrochloride, to induce reversible cytoplasmic vacuolization. The formation of vacuoles was shown not to be due to imbibition of medium. Ultrastructural details obtained from various stages of vacuole formation were compared. In both cases of induction vacuoles were irregular and often appeared membraneless, with little in the way of electron-dense content. They started to form in the perinuclear cytoplasm and progressed towards the periphery. Osmotic stress was not involved since mitochondria remained normal throughout a vacuolization episode.
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation.1 H-nmr relaxation measurements indicated intracellular water restricted in motional characteristics in vacuolized cells. The possibility of a restricted cytoplasmic phase separation as part of a transient adaptation response is raised, and a hypothesis to explain the findings is discussed. 相似文献
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation.
1000.
雪旺细胞源运动神经营养蛋白对周围神经再生的影响 总被引:3,自引:0,他引:3
目的:研究雪旺细胞源运动神经营养蛋白对周围神经再生的影响。方法:60只SD大鼠均分为3组,A和B组分别在桥接于大鼠右侧坐骨神经断端之间的硅胶管内加入26KD和50KD的雪旺细胞源运动神经营养蛋白,C组加PBS液作为对照。术后1~6月每隔半月测定实验侧坐骨神经功能指数,术后3月测定实验侧坐骨神经的电生理和形态学指标。结果:A和B组实验侧坐骨神经的功能指数、电生理和形态学指标与C组比较,差别有非常显著性。结论:26KD和50KD雪旺细胞源运动神经营养蛋白对周围神经再生有促进作用。 相似文献