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21.
Shang-Jin Shi Hiromi Rakugi Koichi Higashimori Jitsuo Higaki Hiroshi Mikami Toshio Ogihara 《Clinical and experimental pharmacology & physiology》1994,21(10):767-773
1. We previously reported that angiotensin II release from the mesenteric arteries of Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) increased in a time-dependent manner as a result of the isolation of the arteries and perfusion. This phenomenon appeared to be due to the withdrawal of circulating angiotensin II (AII). 2. The purpose of the present study was to test the hypothesis that vascular AII generation may be negatively regulated by circulating AII in WKY and SHR, and to clarify the role of this vascular angiotensin II in the sustained hypertension of SHR following nephrectomy. 3. The mesenteric arteries from kidney-intact and nephrectomized WKY and SHR were perfused and the amount of AII released into the perfusate was measured. The effects of the angiotensin converting enzyme inhibitor, captopril, and the effects of supplementation of renal renin and circulating angiotensins to nephrectomized rats, by blood exchange between kidney-intact and nephrectomized rats, on AII release were examined to clarify the pathway of vascular AII generation after nephrectomy. 4. Nephrectomy caused augmentation of vascular AII release both in WKY and SHR in spite of the abolishment of circulating renin. Captopril reduced this enhanced release of AII, but blood exchange did not affect it. There was no significant difference in these responses between WKY and SHR. 5. These results suggest that WKY and SHR have in common a potent pathway for production of vascular AII in response to the withdrawal of circulating AII, although this pathway is not responsible for the sustained hypertension of SHR after nephrectomy. The precise pathophysiological role of this pathway remains to be elucidated. 相似文献
22.
分别采用联合火箭免疫电泳技术和酶法对49例冠心病患者和50例健康人血清载脂蛋白 A_1(apoA_1),载脂蛋白 B_(100)(apoB_(100)),以及血清总胆固醇(TC)、甘油三酯(TG),高密度脂蛋白胆固醇(HDL—ch)的含量进行了测定。结果冠心病患者血清 apoB_(100)(0.99±0.26g/L)明显高于健康人(0.62±0.18g/L);而apoA_1/apoB_(100)比值(1.22±0.35)则明显低于健康人(2.12±0.49);TC,TG,HDL-ch 的含量亦有统计学意义。提示,在预示冠心病危险因素的各种脂类及脂蛋白中,以 apoB_(100)增高 apoA_1/apoB_(100)比值降低最为灵敏,最为准确,且高于单纯测定TC,TG 和 HDL-ch。 相似文献
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Efficacy of radical neck dissection for the control of cervical metastasis after radiotherapy for nasopharyngeal carcinoma 总被引:5,自引:0,他引:5
Fifty-one patients who had persistent or recurrent neck disease from nasopharyngeal carcinoma after radiotherapy underwent radical neck dissection. The follow-up period ranged from 0.5 to 9 years (median: 2 years). Multiple cervical lymph node involvement was present in 51% of the patients (26 of 51). Malignant cells were detected in 88% of the resected specimens (45 of 51). The clinical sign of fixation of lymph node is the only factor that affects the successful control of neck disease (p = 0.04). Extracapsular extension of the nodal disease was present, and 35% of the lymph nodes were adherent to surrounding structures at operation (18 of 51). There was one hospital mortality and the overall morbidity was minimal. The actuarial survival at 5 years was 38%, and the probability of control of neck disease was 66%. Radical neck dissection is effective in controlling post-irradiation cervical metastasis from nasopharyngeal carcinoma. 相似文献
25.
MRI同层动态增强对垂体微腺瘤的诊断价值 总被引:3,自引:0,他引:3
目的:分析垂体微腺瘤的MPd同层动态增强特征。方法:对40例临床怀疑为垂体微腺瘤的病人行同层动态增强MPd扫描,并绘出时间一信号强度曲线图。结果:40例病人中共检出垂体微腺瘤26例。同层动态增强后垂体微腺瘤的MPd表现为圆或椭圆形的低或稍低信号,似“充盈缺损”;垂体微腺瘤的最大信号强度多出现在注入造影剂后32~96s,以64s最明显。结论:同层MPd动态增强对垂体微腺瘤的诊断有较高价值。 相似文献
26.
结肠癌伴糖尿病病人的围手术期护理 总被引:2,自引:0,他引:2
[目的]探讨结肠癌伴糖尿病围手术期的最佳护理措施。[方法]对41例患有糖尿病的结肠癌围手术期病人,采取术前心理护理、控制血糖、清洁肠道、术后安置合适体位、加强引流管护理、积极预防并发症、良好的营养支持。针对易发生感染性并发症的特点,加强对呼吸道、皮肤、泌尿系、伤口感染预防的护理。[结果]发生与感染有关的并发症5例,其中肺部感染2例、切口感染2例、尿路感染1例。[结论]通过以上方法护理,使围手术期并发症明显减少,而且方法简便易行,容易做到。 相似文献
27.
MHC—I类抗原加工途径异常与肿瘤关系的研究进展 总被引:1,自引:0,他引:1
随着免疫学研究的不断深入,MHC-I类抗原呈递细节已逐渐明晰,全面认识肿瘤细胞MHC-I类相关抗原加工途径缺陷或改变与肿瘤生物学及肿瘤临床的关系,将有助于肿瘤的诊治和预防。 相似文献
28.
目的 为构建生物人工肝进行肝细胞的准备。方法 采用胶原酶半原位灌流法分离单个乳猪肝细胞,并对其活力及单层和聚集培养后的白蛋白、尿素合成功能进行检测。结果 采用本方法从每头乳猪中分离到的单个肝细胞数为(3.1±1.5)×10~(10),活性超过95%。在加入激素和生长因子的培养基中单层培养时,肝细胞功能良好,可维持2周左右。而在未加入激素和生长因子的培养中肝细胞虽能存活1周,但功能于24h后即丧失。球形聚集培养可实现肝细胞的大量培养,且生物学活性较单层培养显著提高。结论 采用胶原酶半原位灌注法所得单个乳猪肝细胞基本能满足构建生物人工肝对肝细胞数量的要求。聚集培养接种密度大,细胞生物学活性高,可用于构建生物人工肝。 相似文献
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30.
A randomly selected sample of 662 12-year-old Hong Kong children, 529 of whom were Southern Chinese and 133 non-Chinese, was clinically examined for dental caries. The DMFT values were 2.76 and 1.66 for the Chinese and non-Chinese children, respectively. The D component for the Chinese children was 2.12, while for the non-Chinese children it was only 0.45. Approximately 24.0% of the Chinese children had attended the dentist because they were in pain. Only 3.8% of the Chinese children had sought orthodontic or preventive treatment, compared with 24.0% of the non-Chinese children. Although these findings indicate the caries experience to be well below the FDI/WHO global goal for the year 2000, there is a great need to increase the level of dental awareness among Chinese children. 相似文献