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991.
Xin-Da Zhou Zhao-You Tang Ye-Qin Yu Bing-Hui Yang Ji-Zhen Lu Zhi-Ying Lin Zeng-Chen Ma Bo-Heng Zhang 《Journal of cancer research and clinical oncology》1994,120(6):369-373
The long-term prognosis of surgery for hepatocellular carcinoma (HCC) is not yet satisfactory, the main reason being the high recurrence rate. The authors report the results of a long-term follow-up of 308 patients with HCC who became -fetoprotein-(AFP)-negative after resection between 1975 and 1991. By March 1992, there was recurrence in 134 patients (43.5%). The 1-, 3-, 5- and 10-year recurrence rates were 9.2%, 38.8%, 54.9% and 85.0%, respectively. The 5-year survival rate was 49.7% for patients who had undergone a second hepatic resection (n=48). Analysis of factors influencing postoperative recurrence indicated that patients subjected to mass survey, with a lower -glutamyltransferase level, at an early stage of TNM classification, with a tumour of less than 5 cm, without tumour embolus, and with postoperative immunotherapy had a lower incidence of recurrence. It is concluded that the earlier the disease is diagnosed, the less the recurrence rate; adjuvant immunotherapy may reduce postoperative recurrence, and the early detection and resection of a recurrent tumour are important to prolonging survival further after curative resection of HCC.Abbreviations HCC
hepatocellular carcinoma
- AFP
-fetoprotein
- HBsAg
hepatitis B surface antigen
Presented in part at the 4th Wilson T. S. Wang International Surgical Symposium, 11–13 December 1992, Hong Kong. 相似文献
992.
Serotonin (5-HT) nerve terminals innervate sympathetic preganglionic neurons of the intermediolateral cell column (IML); however, neither the depolarization-induced release of 5-HT nor the presence of presynaptic modulatory autoreceptors have been directly studied in this system. We used in vitro superfusion of the microdissected intermediate area (including the intermediolateral cell column, intercalated nucleus, and central autonomic nucleus) of the rat thoracic spinal cord to measure basal and stimulated release of preloaded [3H]5-HT. Elevated K+ evoked a concentration- and Ca2+ dependent release of [3H]5-HT. Exogenous 5-HT and the 5-HT1B agonist, CGS-12066B, both decreased the K+-stimulated release of [3H]5-HT. A 5-HT1B antagonist (methiothepin) blocked the 5-HT- and the CGS-12066B-induced inhibition of K+-evoked release of [3H]5-HT. A 5-HT1A antagonist (NAN-190) did not alter the inhibitory actions of exogenous 5-HT. Moreover, a 5-HT1A agonist (8-OH-DPAT), a 5-HT2A/2C agonist [(+/-)-DOI hydrochloride], and a 5-HT3 agonist (2-methyl-5-HT) did not alter the K+ evoked release of [3H]5-HT. These data demonstrate that 5-HT is released from the intermediate area of the rat thoracic spinal cord. The 5-HT receptor subtype involved in the inhibition of the evoked release of [3H]5-HT is of the 5-HT1B subtype. These findings may help clarify the complex role of 5-HT in spinal regulation of the sympathetic nervous system. © 1994 Wiley-Liss, Inc 1 This article is US Government work and, as such, is in the public domain in the United States of America. 相似文献
993.
应用反向被动血凝集抑制试验和血凝集抑制试验检测流行性出血热患者早期血清(7病日内)中病毒核蛋白、膜蛋白抗体。103例患者血清,仅核蛋白抗体出现者33例,病情转径及无变化者31例(93.94%).而转重者仅2例(6.06%),且其血清抗体主要为IgG型。仅膜蛋白抗体出现的患者9例,病情转重者8例(88.89%),其抗体主要为IgM.核蛋白、膜蛋白抗体均阳性的61例患者,病情转归介于上述二者之间.提示:核蛋白抗体先出现的患者,病情多转轻,而膜蛋白抗体先出现的患者,病情普遍转重,似与病毒的"一次性打击"有关。在仅核蛋白抗体出现的患者中,有2例病情转重,但其抗体球蛋白类型为IgG,故尚不能排除本病有"二次感染"的可能,这一现象在推行本病预防接种时值得重视,另对进一步探讨本病的发病机理及预测患者的病情转归亦具参考价值。 相似文献
994.
995.
所谓“小粘膜”型胃癌系指病灶直径小于4cm,局限于粘膜层或仅有轻度粘膜下层侵犯的早期胃癌。本文总结经内镜发现并得到手术、病理证实的“小粘膜”型胃癌12例,着重对期诊断问题作一探讨。 相似文献
996.
Serotonin (5-HT), substance P (SP), neurokinin A (NKA), and thyrotropin-releasing hormone (TRH) coexist in the nerve terminals of the intermediolateral cell column (IML) of the thoracic spinal cord. The Ca2+-dependent release of 5-HT from the microdissected intermediate area (including the IML) of the rat thoracic spinal cord, and the 5-HT1B autoreceptor regulator of 5-HT release, were previously demonstrated. In this paper, the effects of SP, NKA, TRH, and/or their analogs on the release of [3H]5-HT from the intermediate area were investigated using an in vitro superfusion system. Both SP (the endogenous ligand for neurokinin-1 (NK1) receptor) and an NK1, agonist (GR 73632) significantly increased the basal release of [33H]5-HT. SP and GR 73632 did not change the K+-stimulated release of [3H]5-HT. The effect of the NK1 agonist on the basal release of [3H]5-HT was dose-dependent, was reduced by an NK1 antagonist (GR 82334), and was not dependent on extracellular Ca2+. Neither NKA, an NK2, agonist (GR 64349), nor a TRH analog (MK-771) altered the basal or stimulated release of [3H]5-HT. These data suggest that basal release of 5-HT from the intermediate area of the rat thoracic spinal cord is regulated by SP (acting through an NK1 receptor), but not by NKA or TRH. These results provide evidence for the role of SP as a modulator of serotoninergic neurons in the intermediate area of the thoracic spinal cord, and may help to clarify the role of coexisting neurochemicals in the spinal regulation of the sympathetic nervous system. © 1995 Wiley-Liss, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America. 相似文献
997.
A new type of ultra-short acting -blocker which might prove advantageous in treating acute arrhythmias was designed, synthesized and investigated. Based on the soft drug inactive metabolite approach, the inactive phenylacetic acid metabolite of both metoprolol and atenolol was reactivated by esterification with sulfur-containing aliphatic alcohols. Since the sulfur-containing moieties are labile to the ubiquitous esterases, the new compounds should be inactivated by a one step enzymatic cleavage back to the inactive phenylacetic acid derivative. Pharmacological and pharmacokinetic profiles of the new compounds were evaluated in rats and rabbits. Isoproterenol-induced tachycardia was inhibited with short-term infusion of each compound. This tachycardia blocking effect rapidly disappeared upon termination of infusion, while -blocking activity was 2–4-fold longer after comparable doses of the short-acting -blocker, esmolol. The rapid recovery from the -receptor blockade is believed due to fast hydrolysis of the soft drugs in the body. This is supported from in vitro results showing the tl/2 of esmolol is about 10-fold longer than the new soft drugs in rat, rabbit, dog and human blood. Hydrolysis studies in phosphate buffered solutions indicated that the esters are labile to base-catalyzed hydrolysis. However, the relative t1/2 values measured in biological media compared to phosphate buffered solution clearly support rapid enzymatic cleavage of the soft drugs. Interestingly, one of the soft -blockers, the sulfonyl ester derivative, showed a unique property of exhibiting good -receptor blocking activity without significant hypotensive action. 相似文献
998.
Li J Mori M Yang Y Inoue H Mimori K Shibuta K Nakashima H Mafune K Shimada Y Barnard G Sugimachi K Akiyoshi T 《International journal of oncology》1995,7(2):257-260
The multiple tumor suppressor 1 (MTS1) gene is homozygously deleted frequently in cell lines derived from a wide variety of tumors. We investigated the deletion of the MTS1 gene in esophageal cancer cell lines and primary esophageal squamous carcinomas using the polymerase chain reaction. Sixteen and 15 of 23 esophageal cancer cell lines showed homozygous deletion of MTS1 exon 1 and exon 2, respectively, while none of 21 primary esophageal carcinomas showed the deletion. An analysis of MTS1 gene mutations was carried out by direct DNA sequencing in 8 cell lines and 21 primary carcinomas showing no homozygous deletion. In contrast to previous reports of esophageal carcinoma, there were no mutations recognized in the region sequenced. Our study suggests that the inactivation of the MTS 1 gene may play an important role in esophageal carcinoma cell lines but may be less important in primary carcinomas of the human esophagus. 相似文献
999.
Hep3B and PLC/PRF/5 human hepatoma cells express epidermal growth factor (ECF) mRNA and secret this polypeptide growth factor into the culture medium. The production of EGF was inhibited by sodium butyrate in a dose-dependent manner. EGF receptor numbers in both cell lines were increased after treatment with butyrate for 2 days, In addition, the binding affinity of EGF to its receptor was decreased in butyrate-treated PLC/PRF/5 cells while it did not change in Hep3B cells. EGF-stimulated cell growth in PLC/PRF/5 cells was attenuated by sodium butyrate whereas no significant inhibition df cell growth of Hep3B cells was found in the same condition. Our results suggest that EGF acts as an autocrine growth stimulator in human hepatoma cells and sodium butyrate can differentially regulate the responses of hepatoma cells to EGF by modulating the differentiation states of these cells. 相似文献
1000.
We determined if we could transfer X-radiation resistance from CHO AA8 cells to their radiosensitive, mutant V3 cells by several methods. These methods include co-incubating the two cell lines for three days before irradiation, adding heavily-irradiated AA8 to V3 cells following irradiation of the latter and then co-incubating these cells for at least eight days during the colony-forming assay and lastly, adding conditioned medium from unirradiated, subconfluent AA8 cells to V3 cultures and incubating for two days before irradiation. None of these procedures enhanced the clonogenic survival of the V3 cells to a single dose of 4 Gy X-radiation. Adding heavily-irradiated V3, instead of AA8, cells did not increase the clonogenic survival of the 4 Gy-irradiated V3 cells either, indicating that there was no autocrine mode of action. Moreover, adding conditioned medium from a related CHO cell line, K1, to its own radiosensitive, mutant 5-11 and incubating for two days before irradiation did not enhance clonogenic survival of the latter to a single dose of 3 Gy X-radiation. We therefore conclude that it is unlikely that CHO cells have the X-radiation resistance factor that has been reported in some mouse melanoma cell lines by other investigators. 相似文献