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91.
胃癌病人天然杀伤细胞活性监测 总被引:2,自引:0,他引:2
报道微量细胞毒试验——LDH 释放法用于对胃癌病人临床免疫的监测.测定100例正常人和50例胃癌病人外周血 NK 细胞毒.结果:正常人值为36.10±5.68,胃癌组中,10例早期胃癌为28.76±4.70,25例进展期胃癌为14.51±5.80,15例晚期胃癌为11.86±4.43,与正常人值比较,P 值分别>0.05,<0.01和<0.01.NK 细胞毒活性随胃癌病变的进展和肿瘤体积的增大而逐渐降低,手术切除肿瘤后可有不同程度回升,甚至恢复到正常水平。长期化疗能损伤 NK 活性. 相似文献
92.
门脉高压性胃病患者的胃壁血气变化 总被引:1,自引:0,他引:1
作者观测了43例门脉高压症患者股动脉血PO2、胃网膜有动静脉胃壁支血PO2、胃壁支静脉及肘静脉血pH、HCO3-和胃网膜右静脉压力,其中23例并有非出血期门脉高压性胃病。结果表明:①门脉高压症患者的股动脉血PO2低于对照组;②门脉高压症患者胃网膜右动静脉胃壁支血氧分压差低于对照组,胃网膜右静脉压力高于对照组,胃壁支静脉血pH和HCO3-低于对照组和同组肘静脉血。并有门脉高压性胃病者这些变化更为显著。提示门脉高压性胃病的发病机制在于门脉系压力增高、胃粘膜下动静脉短路开放、胃粘膜缺血缺氧和胃壁局部酸中毒。 相似文献
93.
D. A. Haskins J. S. Jahr M.D. M. Texidor U. Ramadhyani 《Acta anaesthesiologica Scandinavica》1992,36(6):513-515
Omeprazole is a substituted benzimidazole that causes dose-dependent intracellular inhibition of gastric acid secretion in humans. This double-blind study examined the effect of omeprazole in decreasing gastric acidity and gastric residual volume in outpatient adults. Unpremedicated outpatients, ASA I-III, 18 years or older (n = 17), were randomly assigned to receive omeprazole 80 mg, or placebo by mouth the night before scheduled elective outpatient surgery. The patients were fasted for 8 h prior to surgery. After the patient was anesthetized, an orogastric tube was inserted with proper placement verified by auscultation for gastric sounds. Gastric residual contents were withdrawn into a Luken's trap, and pH was then determined and gastric volume indexed to weight (ml.kg-1). Data were analyzed by a t-test, with P less than 0.05 considered statistically significant. Patient characteristics of both groups were similar. There was a statistically significant difference between the two groups for pH (P = 0.02), but not between the two groups for gastric volume indexed to weight (P = 0.07). 相似文献
94.
应用原位杂交技术,观察了二乙基亚硝胺(DEN)诱发大鼠肝癌前病变组织中胎盘型谷胱甘肽S转移酶(GST-P)mRNA的表达。结果显示,GST-PmRNA主要在癌前病变肝组织中的变异灶及灶外卵圆形细胞内表达,且在变异灶间或和同一灶内阳性细胞间表达程度不尽一致,而正常肝、再生肝组织中未见其表达。提示在分子水平上变异灶细胞及卵圆型细胞可能成为实验性肝癌的癌前期细胞 相似文献
95.
Abstract The aim was to measure the effect of gastric electrical stimulation on the frequency of canine antral pacesetter potentials (PPs), the strength of antral contractions, and the rate of gastric emptying while fasting, after feeding and with pentagastrin stimulation. Four conscious dogs with a stimulating electrode placed 10 cm proximal to the pylorus and recording electrodes and strain gauges placed 7, 5 and 3 cm proximal to the pylorus underwent myoelectric and strain gauge recordings while fasting, after feeding (250 ml 5% dextrose labelled with polyethylene glycol), and during pentagastrin infusion (0.5 μg kg?1 min?1) on four separate days. On each day, electrical stimulation was done using one of four stimulation frequencies (0, 6, 30 and 1200 stimuli per minute ***[s.p.m.]). Stimulation at 6 and 30 s.p.m. increased the fasting and fed PP frequency, whereas 1200 s.p.m. stimulation did not. Feeding decreased the maximum driven frequency, and pentagastrin increased it. Neither the motility index nor the gastric emptying rate were consistently changed by stimulation at any frequency. In conclusion, canine proximal antral stimulation at 6 and 30 s.p.m. sped PP frequency during fasting and after feeding, but stimulation over a wide range of frequencies had little effect on gastric contractions and emptying. 相似文献
96.
紫杉醇诱导体外培养胃腺癌细胞系SGC-7901凋亡 总被引:2,自引:0,他引:2
目的:研究紫杉醇对胃腺癌细胞系SGC—7901的凋亡诱导作用。方法:紫杉醇不同浓度、不同作用时间分别处理胃腺癌细胞系SGC—7901。采用MTT法测定胃癌细胞的生长抑制率,通过组织学观察、TUNEL等手段检测胃腺癌细胞系SGC--7901细胞凋亡情况。结果:紫杉醇对胃腺癌细胞系SGC—7901有明显的抑制作用,并在一定剂量和时间范围内诱导胃腺癌细胞系SGC—7901凋亡,随着药物浓度的增加及时间的延长,凋亡细胞明显增多,当紫杉醇作用浓度为20μmol/L以上时,细胞出现破碎、坏死。结论:紫杉醇对胃腺癌细胞系SGC—7901有明显的抑制作用,诱导凋亡是其发挥抗癌作用的机制之一。 相似文献
97.
B. Hohenester A. Rühl O. Kelber† & M. Schemann 《Neurogastroenterology and motility》2004,16(6):765-773
Functional dyspepsia (FD) is amongst the most common functional gastrointestinal disorders. Symptomatic treatment includes the use of herbal preparations whose effects on gastric motility are unclear. The present study aimed at investigating the effects of STW 5 (Iberogast), a fixed combination of hydroethanolic herbal extracts, on gastric motility in vitro. Muscle strips from guinea-pig gastric fundus, corpus and antrum were set up in organ baths either in circular or longitudinal orientation. Addition of ethanol-free STW 5 to the organ baths (32-512 microg mL(-1)) dose-dependently evoked a sustained and reversible relaxation of circular and longitudinal fundus and corpus muscle strips without changes in phasic activity. In contrast, antral muscle strips responded to STW 5 with a significant increase in the contractile force of phasic contractions without changes in tone. All effects were resistant to tetrodotoxin (0.5 micromol L(-1)), atropine (1 micromol L(-1)), omega-conotoxin GVIA (0.5 micromol L(-1)), capsaicin (1 micromol L(-1)) or L-NAME (100 micromol L(-1)), suggesting that neither nerves nor nitric oxide pathways were involved. These data demonstrate that STW 5 profoundly alters gastric motility in a region-specific but not layer-specific manner and thus implicates Iberogast in the treatment of FD patients suffering from motility disorders with impaired fundus accommodation and/or antral hypomotility. 相似文献
98.
K. Jonderko A. Kasicka-jonderko B. Krusiec-świdergoł M. Dzielicki L. Strój M. Doliński K. Doliński B. Błońska-fajfrowska 《Neurogastroenterology and motility》2005,17(6):800-809
AIM: To check on reproducibility of parameters of the cutaneous electrogastrogram registered at a close or a distant time span. METHODS: Twenty-two volunteers recruited by an advertisement (11 females and 11 males, median age 25 years, range: 18-35) underwent three surface electrogastrography examinations of which two were taken on consecutive days and the third one was accomplished at least 2 weeks before or after the two other sessions. The examination involved a 30-min fasted recording, followed by a 90-min postprandial registration after intake of a 394-kcal mixed solid-liquid test meal. RESULTS: Parameters of the electrogastrogram pertaining to the frequency of the gastric slow waves exhibited good to moderate reproducibility, whereas fair reproducibility characterized parameters expected to describe the power of gastric slow waves. With the exception of the difference fed minus fasted power (DeltaDP), in no instance was the medium term reproducibility any worse than the short term one. Categorical data analysis revealed that the relative time share of normogastria postprandially exhibited a better reproducibility than in the fasted period. The Cohen's kappa-value of 0.459 for the DeltaDP for the medium term reproducibility placed this parameter within the range of moderate agreement between repeat examinations. Of the two two-parameter combinations considered, the alliance of the fasted and fed normogastria performed worse than any of those parameters considered alone, whereas a combination of the DeltaDP with the fed-state normogastria revealed a kappa-value amounting to 0.510 for the medium term reproducibility. CONCLUSIONS: The feasibility of some electrogastrographic parameters to convey clinically useful information may be hampered by their fair reproducibility. Recoding of parameters of the cutaneous electrogastrogram from primary continuous to secondary categorical may help achieve a better agreement between repeat examinations. 相似文献
99.
目的 研究十二指肠溃疡患者胃上皮化生和幽门螺杆菌的关系。方法 收集门诊行上消化道胃镜检查确诊的十二指肠溃疡患者70例,另选胃和十二指肠黏膜正常患者55例为对照组。用快速尿素酶法和幽门活组织检查半定量法检测幽门螺杆菌(Hp),苏木素一伊红染色和Schiff过碘酸染色半定量法检测十二指肠球部胃上皮化生。结果 十二指肠溃疡患者与对照组相比,十二指肠球部胃上皮化生检出率高;十二指肠球部胃上皮化生检出率和评分与胃幽门部Hp的检出率和评分无相关关系。结论 Hp不是十二指肠黏膜胃上皮化生的决定因素,也不是十二指肠黏膜胃上皮化生范围得以扩展的因素。十二指肠溃疡病本身的一些特点是十二指肠黏膜胃上皮化生的主要因素。 相似文献
100.
胃幽门弯曲菌感染对胃癌发生影响的探讨 总被引:1,自引:1,他引:0
应用Warthin-starry镀银技术检查胃幽门弯曲菌,对中国胃癌高发区及美国胃癌高发区新奥尔良检查了300例具有胃症状的胃粘膜标本。结果发现幽门弯曲菌阳性率为60~62%,并且看到这种细菌的感染与慢性胃炎病变的程度有明显的关系。本文探讨了幽门弯曲菌的感染与胃癌癌前病变的关系。 相似文献