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51.
Yoshikazu Noguchi Tatsuo Makino Takaki Yoshikawa Katsutoshi Nomura Kuniyasu Fukuzawa Akihiko Matsumoto Takuko Yamada 《Surgery today》1996,26(1):36-41
This study was conducted to investigate the role of tumor necrosis factor- (TNF-) and interleukin-2 (IL-2) in inducing cancer cachexia, and the results were compared with those obtained from our previous study on Fisher 344 rats with methylcholanthrene-induced sarcoma. Three groups of male Fisher 344 rats received one of the following regimens: 4×104 IU of human recombinant TNF- per rat per day subcutaneously (sc) for 5 consecutive days (n=5), 3.5×105 U human recombinant IL-2 per rat per day sc for 14 consecutive days (n=5), or normal saline (n=5). The activities of both phosphoenolpyruvate carboxykinase (PEPCK) and malic enzyme (ME) were increased slightly in the IL-2 group. Furthermore, LPL activity was significantly increased in the adipose tissue of the TNF group and in the cardiac muscle of the IL-2 group, but not in that of the TNF group. These results show that there is a significant difference between the metabolic alterations seen in the tumor-bearing state and those induced by either TNF- or IL-2 alone. Thus, it is unlikely that IL-2 or TNF- is the sole mediator of cancer cachexia in this tumor and rat model. 相似文献
52.
In rats, circulating corticosterone and insulin are involved in regulation of the hypothalamic neuropeptide Y (NPY) system, which in turn, is involved in regulation of the hypothalamic-pituitary-adrenal (HPA) axis. Since the HPA axis and stress responsivity is altered in diseases such as depression, we investigated interactions between the effects of stress and antidepressant drug treatment on arcuate nucleus and locus coeruleus NPY mRNA expressions using in-situ hybridization histochemistry. After acute (2 h) and repeated immobilization (2 h daily, for 14 days), plasma concentrations of corticosterone increased, and those of insulin decreased. The expression of NPY mRNA was significantly increased in the arcuate nucleus, but was unchanged in the locus coeruleus following acute and repeated immobilization. Adrenalectomized rats with systemic corticosterone replacement (ADX+CORT), whose corticosterone concentration was maintained at approximately 50-100 ng/ml during repeated stress, showed a decrease in plasma insulin and an increase in arcuate nucleus NPY mRNA similar to that observed in sham rats, suggesting that changes in NPY mRNA levels are more closely tied to circulating insulin than to circulating corticosterone. In contrast, locus coeruleus NPY mRNA expressions in ADX+CORT rats were significantly higher than those in sham rats after repeated stress. Desmethylimipramine (DMI) treatment for 24 days did not affect basal plasma concentrations of corticosterone or insulin, or arcuate nucleus NPY mRNA expressions, but significantly decreased basal levels of locus coeruleus NPY mRNA compared to saline-treated rats. After repeated immobilization (2 h daily, for 4 days), DMI significantly reduced the stress-induced rise in locus coeruleus NPY mRNA levels, but potentiated the stress-induced rise in arcuate nucleus NPY mRNA expression. These results demonstrate that: (1) the increase in arcuate nucleus NPY mRNA expressions in stressed rats closely follows the decrease in plasma concentrations of insulin; (2) increases in NPY mRNA expressions occur in the absence of changes in plasma corticosterone; and (3) desipramine treatment potentiated the effect of stress on arcuate nucleus NPY mRNA expressions, but blocked the repeated stress-induced increase in locus coeruleus NPY mRNA expressions. Thus, NPY mRNA expression in the arcuate nucleus and the locus coeruleus is sensitive to the effects of stress and to the antidepressant drug desipramine, but the arcuate nucleus NPY system is regulated by different mechanisms than the locus coeruleus NPY system. The results provide further evidence for the importance of circulating insulin in the regulation of the arcuate nucleus NPY system. 相似文献
53.
升麻地上部分化学成分研究升麻地上部分化学成分研究 总被引:3,自引:0,他引:3
目的 为开发中药升麻(Cimicifuga foetida L.)的地上部分资源,从中寻找新的天然活性成分。方法 利用多种色谱技术进行分离纯化,根据理化性质和现代波谱技术并辅以化学方法进行结构鉴定。结果 从升麻地上部分80%乙醇提取物的乙酸乙酯部分分得5个9,19-环菠萝蜜烷型三萜皂苷和1个甾醇苷。分别鉴定为:西麻苷I(1),西麻苷II(2),升麻醇半乳糖苷(3),12β-羟基升麻醇木糖苷(4),12β-羟基升麻醇阿拉伯糖苷(5),胡萝卜苷(6)。结论 1和2为新化合物,4及5为首次从该植物中分得。 相似文献
54.
Magnetic resonance imaging evaluation and arthroscopic resection of localized pigmented villonodular synovitis of the knee 总被引:6,自引:0,他引:6
Diagnosis of localized pigmented villonodular synovitis is clinically difficult, and plain radiographs are usually normal. This article presents five patients with localized pigmented villonodular synovitis of the knee. Symptoms suggested a meniscal lesion in three patients and a loose body in two. Magnetic resonance imaging performed prior to arthroscopic resection revealed a preoperative diagnosis of a tumor in all five patients. Magnetic resonance imaging is a valuable clinical tool for the assessment of intra-articular soft-tissue tumors of the knee that may otherwise be misdiagnosed. 相似文献
55.
目的 检测腹腔积液脱落细胞端粒酶活性,探讨端粒酶对良恶性腹腔积液的鉴别诊断价值。方法 运用半定量TRAP-银染法,检测38例恶性腹腔积液和20例良性腹腔积液(对照组)脱落细胞端粒酶活性。结果 肝硬化、结核性腹膜炎腹腔积液脱落细胞检测未发现端粒酶活性,而38例癌性腹腔积液36例(94.7%)端粒酶阳性。所有细胞学检查阳性的恶性腹腔积液端粒酶均为阳性,而3例恶性腹腔积液者,细胞学检查阴性但端粒酶阳性,当复查细胞学检查时,其中1例发现了癌细胞。结论 癌性腹腔积液端粒酶阳性。端粒酶活性的检测对良、恶性腹腔积液有重要鉴别诊断价值,尤其对细胞学检查阴性的病例。 相似文献
56.
端粒酶抑制剂对小鼠胃癌放疗的增敏作用研究 总被引:2,自引:0,他引:2
目的:探讨端粒酶抑制剂对动物在体肿瘤的治疗作用及对放射治疗的增敏价值。方法:将SGC-7901胃癌细胞接种BALB/c小鼠,采用端粒酶抑制剂AZT联合放疗治疗小鼠胃癌,观察其对肿瘤体积和肿瘤端粒酶活性的影响。结果:未治疗组小鼠肿瘤体积增加了2.5倍,而AZT组、放疗组及AZT联合放疗组肿瘤体积分别缩小了26.3%、36.8%及70.5%。肿瘤端粒酶活性检测,未治疗组、AZT、放疗均能使肿瘤体积缩小并降低前几天粒酶活性分别为100、55.2、24.5及12.1。结论:AZT放疗均能使肿瘤体积缩小并降低端粒酶活性,且AZT能增加肿瘤的放射敏感性。 相似文献
57.
目的探讨自拟绞贞汤或绞贞冲剂治疗放、化疗引起白细胞减少的疗效,及其对白细胞形态学变化的影响.方法 618例放、化疗引起白细胞减少患者随机分为3组,即绞贞汤(治疗)组518例、焦三仙对照组50例和鲨肝醇、维生素B4西药组50例,观察3组临床疗效及白细胞回升情况;并对50例白细胞低于3.9×109/L末梢血涂片进行细胞形态学分析,对25例白细胞减少为(0.7~3..9)×109/L患者应用绞贞汤或绞贞冲剂治疗前后的细胞形态学改变进行观察.结果①绞贞汤组白细胞回升至4.0×109/L及以上者时间、例数及总有效率分别与西药组和对照组比较,均有显著性差异(P<0.001);②50例白细胞减少患者细胞形态学分析主要为粒细胞绝对值减少、中性粒细胞有中毒性颗粒、单核细胞与淋巴细胞增多等;③绞贞汤或绞贞冲剂治疗白细胞减少为(0.7~3.9)×109/L 25例,白细胞均回升至(4.3~6.7)×109/L.结论绞贞汤或绞贞冲剂治疗放、化疗引起的白细胞减少疗效较好,且无任何副作用,便于临床推广应用. 相似文献
58.
A case of acute-on-chronic renal failure in a 70-year-old woman with ischemic nephropathy and primary hypothyroidism is presented. Her renal function became progressively worse as the level of serum creatinine increased from 283 to 628 micromol/l (3.2-7.1 mg/dl) within 8 months. Her thyroid function had been normal before the exacerbation of renal failure, but it was markedly reduced with a marked elevation of serum thyroid-stimulating hormone. Thyroid hormone replacement therapy resulted in rapid improvement of the renal function to 159 micromol/l (1.8 mg/dl) of serum creatinine. The development of primary hypothyroidism seemed to worsen the already impaired renal function in this case. We suggest the assessment of thyroid function in patients with unexplained deterioration of renal failure. 相似文献
59.
60.
雷公藤属3种植物不同群体和个体中雷公藤甲素的研究 总被引:19,自引:0,他引:19
目的测定雷公藤属3种植物(雷公藤、昆明山海棠和黑蔓)不同群体和个体中雷公藤甲素(tripto lide),为评价雷公藤药材质量和寻找雷公藤的优质种质奠定基础。方法建立雷公藤甲素HPLC测定方法,并测定了全国主要分布区25个群体91个个体的木质部和韧皮部中的雷公藤甲素。结果黑蔓的雷公藤甲素质量分数很低;雷公藤和昆明山海棠种间的雷公藤甲素差异不明显,个体质量分数木质部为1.0×10-6~5.83×10-5;韧皮部为2.3×10-6~1.030×1-0 4。结论雷公藤和昆明山海棠不同个体雷公藤甲素质量分数最高值与最低值相差约50倍,不同居群雷公藤甲素质量分数最高值与最低值相差10多倍,不同来源的药材质量差异极大,严重影响用药的安全性;雷公藤甲素质量分数高的居群位于浙江西南部和中部、湖南新宁、贵州雷山和安徽黄山;湖南新宁、贵州雷山和浙江江山居群中有雷公藤甲素质量分数极高的个体,值得进一步研究,以寻找质量分数高的优良单株。 相似文献