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971.
20例肾胚胎瘤患儿中18例是晚期病人。全部病人均于发现包块前一周~半年(平均50天)在各地儿科门诊以发烧为主诉就诊过,都被诊断为“上呼吸道感染”。3例腹部包块被诊断为肝癌或脾肿大而收住儿科。作者认为,对于不明原因的经常发烧的儿童应疑及该肿瘤。B型超声波有助于早期发现肾胚胎瘤。 相似文献
972.
重新复查我院1960~1980年收治原诊为卵巢女性化性索间质性肿瘤39例的病理切片,可疑者再切片作特殊染色,复查后纠正了11例误诊病例,对确诊的28例的临床表现、病理特征、随访结果及预后等进行了分析。讨论了误诊病例的病理后,建议此类肿瘤中的粒层细胞瘤命名为“恶性粒层细胞瘤”,其恶性度与细胞分级密切相关,预后与卵巢外扩散及治疗是否彻底相关。 相似文献
973.
The patient described here, with malignant non-beta islet cell tumor of the head of the pancreas, was treated by resection of the tumor and metastases. Additional pathology of perforated duodenal ulcer and pyloric stenosis required vagotomy and pyloroplasty. The maintenance of normal gastrin levels after the operation indicates a good prognosis. We believe that the low-risk Zollinger-Ellison patient should be treated surgically and the tumor removed. When no tumor can be detected, parietal cell vagotomy should be performed to assist the pharmacological control of the gastric acid hypersecretion. Extensive surgery, such as total gastrectomy, is no longer the treatment of choice and is reserved for the so-called "cimetidine failure." 相似文献
974.
The liver is a major site for synthesis and catabolism of plasma proteins. Albumin has various binding sites for anionic drugs,
1acid glycoprotein possesses a single binding site for cationic drugs. In spite of extensive protein binding, the liver can efficiently remove drags from the circulation. Intrahepatic dissociation of the drag-protein complex may involve dissociation-limited debinding under non-equilibrium conditions or surface interaction-facilitated dissociation phenomena. During liver or renal disease and acute-phase conditions plasma protein binding of drugs may be affected. Changes in the unbound drag fraction do not always result in proportional changes in clearance or distribution volume. Potential changes in the unbound concentration in steady-state as well as the fluctuations in total plasma levels depend on the extent of protein binding of a drug, the relative change in the unbound drug fraction, type of clearance, the size of the distribution volume, route of administration as well as concomitant changes in intrinsic (cellular) clearance function. Optimization of dosage regimens for certain drags and interpretation of liver function tests with diagnostic dyes may largely benefit from determination of the unbound rather than the total concentration of the drags involved.Part of this work was supported by Grant 900-521-078 from MEDICON, which is subsidized by The Netherlands' Organization of Pure Research. 相似文献
975.
Martin R. Schneider Erwin von Angerer Jelica Prekajac Wolfgang P. Brade 《Journal of cancer research and clinical oncology》1986,111(2):110-114
Summary Diethylstilbestrol (DES), diethylstilbestrol monophosphate (DES-MP) and diethylstilbestrol diphosphate (DES-DP) were tested for their estrogen receptor affinity, estrogenic potency and mammary tumor-inhibiting activity in vitro and in vivo. DES had a much higher receptor binding affinity than its mono-or diphosphate. All three compounds inhibited the growth of the hormone-dependent MCF-7 and hormone-independent MDA-MB 231 breast cancer line only at relatively high concentrations. The estrogenic potency in the immature mouse uterine weight test decreased in the order DES>DES-MPDES-DP. The hormone-dependent MXT mammary tumor of the mouse was inhibited by all three compounds at a dosage of 1.0 mg/kg per week. At a dose of 0.01 mg/kg, DES, DES-MP, and DES-DP stimulated the tumor growth. Thus, for the first time, a biphasic effect on tumor growth was demonstrated in intact mature animals. As the effects of all three compounds were similar in this assay, a cleavage of the phosphate groups is likely. A decrease in estrogenic potency concomitant with a retained antitumor effect of DES-MP and DES-DP compared to DES was not demonstrable in the mature mouse using the MXT assay, only in the uterotrophic test in the immature mouse.Dedicated to Professor Dietrich Schmähl on occasion of his 60th birthdaySupported by the Deutsche Forschungsgemeinschaft and by the Verband der Chemischen Industrie, Fonds der Chemischen Industrie. The authors thank Dr. Weigert, Asta-Werke AG, Degussa Pharma Gruppe, Bielefeld, FRG, for the analysis of DES-MP and DP 相似文献
976.
Previous studies have shown that xenobiotic compounds such as the environmental pollutant -hexa-chlorocyclohexane (-HCH) and the synthetic sex steroid cyproterone acetate (CPA) induce growth of rat liver by hypertrophy and hyperplasia. After withdrawal of the growth stimuli, liver hypertrophy was usually found to be readily reversible. Conflicting observations were made concerning the fate of liver hyperplasia: hepatic hyperplasia persisted when induced by -HCH but was found to be partially reversible when induced by CPA. The present study confirms the reversibility of hepatic hyperplasia induced by CPA in rats: about 30% of liver DNA present at maximal liver enlargement disappeared within 6 days after cessation of CPA treatment. Simultaneously, a dramatic increase in the rate of cell elimination by apoptosis was found. Glutamate-pyruvate transaminase and alkaline phosphatase in serum did not show major increases, suggesting that cell death was not due to lytic membrane damage. Furthermore, if treatment with CPA was continued or resumed, the enhanced DNA content persisted and the number of apoptotic bodies was greatly reduced. These observations suggest that the occurrence of cell death is due to withdrawal of the growth stimulus CPA. It may reflect a regulatory phenomenon serving to maintain homeostasis of cell number.Further studies showed that CPA is rapidly eliminated from rat liver and serum: t 1/2 in the liver is about 11 h. In contrast, -HCH was previously found to be eliminated more slowly: t 1/2 approximately 144 h. The present study revealed that -HCH, CPA and nafenopin lower the number of apoptotic bodies. This suggests that inducers of liver growth can inhibit hepatocellular death by apoptosis. It is concluded that the regression of hyperplasia after CPA withdrawal may be due to its rapid elimination. On the other hand the relatively long persistence of -HCH may result in inhibition of cell death and thereby stabilize hepatic hyperplasia.Abbreviations CPA
cyproterone acetate
- -HCH
-hexachlorocyclohexane
- PB
phenobarbital
- NAF
nafenopin
- AB
apoptotic body
- b.w.
body weight
- p. admin.
post-administration
- GPT
glutamate-pyruvate transaminase
- ALP
alkaline phosphatase
Dedicated to Professor W. Koransky on the occasion of his 65th birthday 相似文献
977.
Amadou Kane Edmond Ekué Creppy Angelika Roth Robert Röschenthaler Guy Dirheimer 《Archives of toxicology》1986,58(4):219-224
The distribution of a single low dose of [3H]ochratoxin A (OTA) in different tissues of male Wistar rats, after administration by intubation, was investigated after 5 h, 24 h and 48 h. This dose corresponds to concentrations encountered in naturally contaminated feed (4 ppm). The distribution of [3H]-label varied with the time elapsed after administration; at 5 h the highest specific label was found in the stomach contents and in decreasing order in: intestinal contents, lung, liver, kidney, heart, fat, intestine, testes, and the lowest in muscles, spleen and brain. With exception of brain, fat, stomach and lung, all tissues showed maximum levels at 24 h, after which time the label decreased steadily, whereas in fat it increased.After a 12-week feeding experiment, with doses of 288.8 g/kg corresponding to an intake of 4 ppm in feed each 48 h, the DNA in liver and kidneys was investigated for damage. By the alkaline elution method combined with micro-spectrofluorimetric determinations of DNA, evidence for DNA single-strand breaks was obtained. These findings support reports on the carcinogenic action of OTA. 相似文献
978.
B. D. Leece M. A. Denomme S. M. A. Li R. A. Towner J. W. Gyorkos B. G. Chittim S. Safe 《Archives of toxicology》1986,59(3):186-189
The effects of o-, m- and p-terphenyl, 2,4-dichloro-, 2,4,6-trichloro-, 2,3,5,6-tetrachloro-, 2,3,4,6-tetrachloro-, 2,4,4'",6- tetrachloro- and 2,3,4,5-tetrachloro-p-terphenyl, 2,3,4,5-tetrachloro-m- and o-terphenyl as inducers of hepatic drug-metabolizing enzymes were determined in immature male Wistar rats. o-Terphenyl, 2,4-dichloro-, 2,4,6-trichloro-p-terphenyl and 2,3,4,5-tetrachloro-o-terphenyl induced 4,4-dimethylamino antipyrine N-demethylase at total dose levels of 300 mol/kg and the 2,3,4,5-tetrachloro-p-terphenyl induced ethoxyresorufin O-deethylase (EROD). In contrast, none of the other terphenyls or polychlorinated terphenyls (PCTs) induced these enzyme activities. Previous studies have demonstrated that 2,3,4,5-tetrachloro-p-terphenyl did not exhibit a high affinity for the 2,3,7,8-tetrachlorodibenzo-p-trachlorodibenzo-p-dioxin (TCDD) receptor protein (EC50= 6.6×10–6M). In contrast, this study showed that 2,3,4,5-tetrachloro-p-terphenyl was more active than either 2,3,4,5-tetrachloro-o- or m-terphenyl as an inducer of EROD. Moreover, the competitive receptor binding EC50 values for the latter two isomers were > 10–5 M and this result was also consistent with their lack of EROD induction activity. Previous studies showed that analysis of the data for a series of 4-substituted-2,3,4,5-tetrachlorobiphenyls indicated that the p-terphenyl structural moiety (i.e. 4-substituent = phenyl) did not interact with high affinity with the receptor protein binding site. Since the 2,3,4,5-tetrachloro o- and m-terphenyls are also poor ligands for the receptor protein, this data and results from other studies indicate that PCT congeners (and commercial mixtures) are therefore unlikely to elicit significant 2,3,7,8-TCDD-like biologic or toxic effects in target species. 相似文献
979.
癌光啉对动物移植瘤的光化学诊治作用 总被引:11,自引:0,他引:11
本文报道了肿瘤光化学诊治新药癌光啉(PsD-007)对三种动物移植瘤(S_(180)肉瘤、Lewis肺癌、U_(14)宫颈癌)的实验性光化学诊治效果,初步探讨了辐照光能量和药物剂量与肿瘤实验性诊治效果的关系。作者采用“透镜光阑”法改善辐射光斑内功率密度分布的不均匀性。提供了一种能比较客观地评价药物对动物移植瘤的光动力学治疗效价的模型体系。 相似文献
980.
目的了解郑州市二七区居民2011—2020年恶性肿瘤死亡流行趋势及对居民寿命的影响情况,为制定恶性肿瘤防治对策提供科学依据。方法对2011—2020年郑州市二七区居民恶性肿瘤死亡资料进行分析,计算恶性肿瘤死亡率、潜在减寿年数(potential years of life lost,PYLL)、标化潜在减寿年数(standardized potential years of life lost,SPYLL)、标化潜在减寿率(standardized potential years of life lost rate,SPYLLR)和人均减寿年数(average years of life lost,AYLL)等指标,采用年度变化百分比(annual percent change,APC)分析率的时间变化趋势。结果2011—2020年郑州市二七区居民恶性肿瘤年均死亡率为114.68/10万,标化死亡率为103.52/10万,男性年均死亡率(146.09/10万)高于女性(84.56/10万)。恶性肿瘤前5位死因依次为肺癌、肝癌、胃癌、结直肠癌和食管癌,共占恶性肿瘤死亡构成的65.36%。2011—2020年该区居民恶性肿瘤死亡率呈上升趋势(APC=3.70%,P<0.001)。0~44岁年龄组恶性肿瘤死亡率处于较低水平,45岁后随年龄增长逐渐升高,75岁以后迅速升高。恶性肿瘤总PYLL为39067人年,SPYLLR为6.73‰,AYLL为12.59年。结论肺癌、肝癌、胃癌、结直肠癌和食管癌是二七区恶性肿瘤预防控制的重点工作,同时宫颈癌和乳腺癌对女性健康的影响不可忽视,应针对主要恶性肿瘤和重点人群开展综合防控措施,以降低恶性肿瘤的死亡率。 相似文献