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111.
Gastric carcinoma is one of the most serious diseases in mankind. Its pathogenesis has not been understood very clearly. Recent researches suggested that oncogenes (such as cyclin D1), antioncogenes (ie., p16, Rb) and cell cycle played an important role in the pathogenesis of gastric carcinoma. But there are few reports about the relationship between these genes in gastric carcinoma and gastric premalignant lesions. In this study, we will discuss these problems. MATERIALS AND METHO…  相似文献   
112.
目的检测慢性胃炎儿童胃液中幽门螺杆菌DNA,探讨其在临床诊断中的实用价值。方法应用PCR检测胃液中幽门螺旋菌DNA,应用Warthin-Starry银染色检测胃粘膜组织中的幽门螺旋菌。结果胃炎组与非胃炎组比较,敏感性为75.0%,特异性为96.2%,两组有显著性差异(P<0.01)。PCR与Warthin-Starry银染色比较,PCR优于Warthin—Starry银染色法。结论PCR检测患儿胃液中的幽门螺旋菌DNA,具有敏感、快速、特异、高效等优点,是基因水平上检测幽门螺旋菌一项新技术,用于慢性胃炎的早期诊断,具有较好的实用价值,值得推广应用。  相似文献   
113.
Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non-scirrhous cancer tissues (n=10) by means of two-dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 Neu-Acα-LacCer, II3 NeuAcα2-LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3+ Gb4=58%) were two times higher than those in non-scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Lea (pentaglycosylceramide) and Leb (hexa- and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells.  相似文献   
114.
Background. In Japan, much attention has recently been paid to super-extended paraaortic lymphadenectomy (PAL) for the treatment of advanced gastric cancer. However, it has been reported that PAL is associated with increased morbidity and mortality, as compared to conventional extended lymphadenectomy (D2 or D3). Therefore, an analysis of the effects of PAL on perioperative changes in the biological responses of patients essential for determining the potential utility of this procedure. Methods. The current non-randomized prospective study included evaluations of perioperative changes in parameters of surgical stress (series I; serum levels of antidiuretic hormone, interleukin-6, trypsin, and phospholipase A 2 ) and immunocompetence (series II; phytohemagglutinin- and concanavalin A-induced blastogenesis, activity of natural killer cells and the ratio of CD4 cells to CD8 cells) in patients with advanced gastric cancer (T3 or T4), comparing groups treated with D3 plus PAL ( n = 12) and D3 ( n = 13), and a control group with early gastric cancer ( n = 16) treated with D1 lymphadenectomy (perigastric N1 nodes) between April 1995 and April 1997. Results. The duration of surgery and the amount of blood lost were longer and greater in the D3 plus PAL group than in the D3 and D1 groups. D3 plus PAL and D3 were associated with significant postoperative increases in parameters of surgical stress, as well as with significant postoperative immunosuppression, compared to results with D1. However, there were no significant differences in the respective parameters between the D3 plus PAL and D3 groups. Conclusions. Our results indicate that there are no essential differences in patients' biological responses between D3 plus PAL and D3 lymphadenectomy. It appears that PAL-associated morbidity can be minimized by very careful manipulation during the dissection of paraaortic lymph nodes. Received for publication on Feb. 10, 1998; accepted on Jun. 3, 1998  相似文献   
115.
The activity of the striatum is regulated by glutamate and dopamine neurotransmission. Consequent to striatal dopamine depletion the corticostriatal excitatory input is increased, which in turn can raise intracellular calcium levels. We investigated changes in the neuronal expression of the calcium binding protein calretinin related to dopamine depletion and l-DOPA administration. Immunohistochemical methods were used to assess calretinin in the striatum of rats with unilateral lesions of the nigrostriatal system. In these animals we observed a loss of the patchy distribution of calretinin fibers. Moreover, after dopaminergic depletion we detected two new, not previously described, calretinin cell types, the presence of which could be related to morphological changes induced by loss of a dopaminergic input. We also found an increase in the number of calretinin-labeled cells in the striatum ipsilateral to the lesion compared to the contralateral striatum or to the striatum of normal rats. This increase was mostly evident at 3 weeks postlesion and tended to decrease toward normal levels at 6, 10, and 18 weeks postlesion. In unlesioned animals, l-DOPA administration did not induce changes in the expression of calretinin. In unilaterally lesioned animals, l-DOPA reversed the increase in the number of calretinin-positive cells induced by the lesion. However, chronic l-DOPA administration was less effective than acute l-DOPA in reversing the effect of the lesion. The present data suggests that striatal calretinin neurons are sensitive to dopamine depletion. Increased expression of calretinin in striatal cells may be consequent to enhanced striatal excitatory input.  相似文献   
116.
鼻内镜下治疗真菌性鼻窦炎93例   总被引:1,自引:0,他引:1  
目的探讨真菌性鼻窦炎经鼻内镜手术治疗的方法及疗效.方法回顾性分析93例真菌性鼻窦炎病例,经鼻内镜下手术治疗的疗效及有关问题.结果93例患者术后经随访3月~2年,窦口引流通畅,无1例复发.结论非侵袭型鼻窦真菌病宜行鼻内镜手术,以彻底清除窦腔病变,术后应继续反复冲洗窦腔,术后不必全身应用抗真菌药物.  相似文献   
117.
胃癌是我国最常见的恶性肿瘤之一,死亡率很高。胃癌的发生是细胞凋亡与增殖调控失衡的结果。现综述细胞凋亡相关基因在胃癌的发生、发展、转归和治疗中的地位及其应用前景。  相似文献   
118.
Hologic FD原理浅析及维护   总被引:1,自引:1,他引:1  
本文浅析了FD(平板探测器)的成像原理,探讨空间分辨率的计算方法,并对DR的使用环境,日常维护、维修作了介绍。  相似文献   
119.
120.
OBJECTIVE To study the inhibition of adhesion and invasion of SGC7901cells into the ECM by integrinβ1 antisense oligodeoxynucleotide asODN.METHODS asODN and control ODN were transfected into SGC7901 cells using liposomes as vectors. The distribution of the ODN was followed by immunochemistry and changes in the expression of integrinβ1 mRNA and protein were determined by RT-PCR and FCM, respectively. The adhesion and invasion into the ECM were measured by the MTT and Boyden chamber methods, respectively.RESULTS Integrinβ1 asODN which was transfected into SGC7901 cells distributed evenly in the cytoplasm and nucleus. PCR and FCM revealed a weakened band at 489bp and a left-shift curve, respectively. Adhesion and invasion assays showed decreased activity with an inhibition rate of 54% and 76%. The extent of decrease induced by integrinβ1 asODN was larger than that caused by random control ODN (P<0.001).CONCLUSION Transfection of integrinβ1 asODN into SGC7901 cells induced a decrease in the expression of integrinβ1 mRNA and protein,resulting in a decrease in adhesion and invasion into the ECM, with a greater effect than random control ODN.  相似文献   
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