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1.
BACKGROUND: Gastric bypass is an established bariatric procedure that has undergone multiple modifications to improve its effectiveness. The side-to-side stapled technique is well recognized, but closure of the gastrotomy/enterotomy by the stapler can potentially narrow the Roux limb. Because of this, many surgeons will hand suture the closure of the gastrotomy/enterotomy. To obviate this difficulty, we inserted the linear stapler from the stomach's greater curvature, using a double-stapled anastomosis that minimized the need for hand suturing. METHODS: We performed a retrospective analysis of 307 patients undergoing this technique for laparoscopic gastric bypass. The weight loss and 30-day morbidity and mortality were tabulated and compared with those in other published series. RESULTS: Of the 307 patients, none died postoperatively. The overall 30-day morbidity rate was 15%. Two leaks from the gastrojejunostomy and 2 from the jejunojejunostomy (1.2%) developed. The mean percentage of excess weight loss was 34% at 3 months, 52% at 6 months, 73% at 1 year, 71% at 2 years, and 69% at 3 years. CONCLUSION: The greater curve approach avoids Roux limb obstruction, minimizes the need for hand suturing, and uses standard trocar incisions. Our short-term follow-up results are similar to those of series of other techniques.  相似文献   
2.
背景:Nissen胃底折叠术(Nissen fundoplication,NF)已不是治疗胃食管返流性疾病(gastroesophageal reflux disease,GERD)的唯一、有效的方法。对于能降低胃酸的手术方式来讲,如高选择性迷走神经切断术(highly selective vagotomy,HSV),也不仅仅是一种辅助治疗方法。对高选择性迷走神经切断术联合Nissen胃底折叠术(Nissen fundoplication with highly selective vagotomy,NFHSV)治疗GERD的作用目前尚无完整的评价。方法:2003年6月~2005年6月8例女性病人接受NFHSV,8例均有6个月GERD病史,经药物治疗症状无缓解,有餐前痛、消化性溃疡或严重的胃炎。平均随访时间12个月,术前、术后进行烧心严重程度评分测定(heart burn severity score,HSS)。结果:平均手术时间110min,无手术并发症。1例术后须用质子泵抑制剂,术后经戒烟5个月后停药。8例术后症状和烧心严重程度评分测定有明显改善。结论:NFHSV是有效的联合手术方式,尚需要进一步的研究证实这一联合术式的完全有效性和安全性。  相似文献   
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Recently an unconjugated hyperbilirubinaemia, without any other abnormalities in liver function test, in 14.3% of HBV Japanese carriers has been noticed. Therefore, it would be possible to argue that the persistent infection of HBV in hepatocytes might play a role in an hypothetical metabolic derangement of bilirubin clearance. Twenty-five subjects in a group of 468 HBsAg+ patients (equal to 5.33%) presented an hyperbilirubinaemia. This percentage was not different from the 5.83% found in 3083 HBsAg- controls coming from the same institution. Therefore we could exclude that in our population the presence of HBV surface antigen itself would determine a statistically higher level of total bilirubin (TB) than in controls. The nicotinic acid (NA) loading test may reveal some bilirubin metabolic defects (i.e. Gilbert syndrome), even in subjects with normal basal values of TB. According to this background, we performed in 11 HBsAg+ males with basal TB higher than 17.1 mumol/l (1 mg%) (group A/1), 13 HBsAg+ males with basal TB lower or equal to 17.1 mumol/l (group A/2) and 14 HBsAg- normal controls matched for sex and age (group B) the NA test according to R?llinghoff et al. All the parameters calculated by the NA test resulted significantly different in the A/1 group compared with the B group, but not different from those found by several authors in the Gilbert's syndrome. On the contrary, no significant differences have been noticed between the latter group and the A/2 group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
6.
After consuming comparable amounts of ethanol, women have higher blood ethanol concentrations than men, even with allowance for differences in size, and are more susceptible to alcoholic liver disease. Recently, we documented significant "first-pass metabolism" of ethanol due to its oxidation by gastric tissue. We report a study of the possible contribution of this metabolism to the sex-related difference in blood alcohol concentrations in 20 men and 23 women. Six in each group were alcoholics. The first-pass metabolism was determined on the basis of the difference in areas under the curves of blood alcohol concentrations after intravenous and oral administration of ethanol (0.3 g per kilogram of body weight). Alcohol dehydrogenase activity was also measured in endoscopic gastric biopsies. In nonalcoholic subjects, the first-pass metabolism and gastric alcohol dehydrogenase activity of the women were 23 and 59 percent, respectively, of those in the men, and there was a significant correlation (rs = 0.659) between first-pass metabolism and gastric mucosal alcohol dehydrogenase activity. In the alcoholic men, the first-pass metabolism and gastric alcohol dehydrogenase activity were about half those in the nonalcoholic men; in the alcoholic women, the gastric mucosal alcohol dehydrogenase activity was even lower than in the alcoholic men, and first-pass metabolism was virtually abolished. We conclude that the increased bioavailability of ethanol resulting from decreased gastric oxidation of ethanol may contribute to the enhanced vulnerability of women to acute and chronic complications of alcoholism.  相似文献   
7.
We have sequenced and compared DNA from the ends of three human chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub- domains with entirely different patterns of homology to other chromosome ends. The distal regions contain numerous, short (<2 kb) segments of interrupted homology to many other human telomeric regions. The proximal regions show much longer (approximately 10-40 kb) uninterrupted homology to a few chromosome ends. A comparison of all yeast subtelomeric regions indicates that they too are subdivided by degenerate TTAGGG repeats into distal and proximal sub-domains with similarly different patterns of identity to other non-homologous chromosome ends. Sequence comparisons indicate that the distal and proximal sub-domains do not interact with each other and that they interact quite differently with the corresponding regions on other, non- homologous, chromosomes. These findings suggest that the degenerate TTAGGG repeats identify a previously unrecognized, evolutionarily conserved boundary between remarkably different subtelomeric domains.   相似文献   
8.
Background: Peripheral B-cell lymphoma of the marginal zone (MALT, low-grade), presenting as localized, extranodal disease, usually affects the elderly. The gastrointestinal tract is the most frequently involved extranodal location, representing 70% of all MALT lymphomas. Recently, numerous other extranodal sites involved by MALT lymphomas have also been described.Patients and methods: From January 1990 to October 1995, 24 patients with untreated nongastrointestinal low-grade MALT lymphoma were submitted to treatments ranging from the local approach of radiotherapy and local -interferon (-IFN) administration to chemotherapy. The tumours were located in the lung (seven cases), conjunctiva (four cases), lachrymal gland and orbital soft tissue (four cases), salivary glands (three cases), skin (three cases), breast (two cases)' and thyroid (one case). All patients had low-grade stage IE tumours.Results: Chemotherapy was administered in 11 patients (six with lung, three with salivary gland, one with breast, and one with thyroid locations); radiation therapy was employed in seven patients (three with lachrymal gland, three with skin, and one with breast locations); local -IFN administration was administered in five patients (four with conjunctival, and one with lachrymal gland sites); and surgery was employed in one patient with a lung tumour. All patients achieved complete remissions; three local recurrences and two relapses in other sites were observed. The global five-year survival rate was 100% with a relapse-free survival rate of 79%.Conclusions: These data confirm the significant efficacy of different therapeutic approaches to specific sites inbes obtaining a good remission rate for nongastrointestinal localized low-grade MALT lymphomas.  相似文献   
9.
Here we confirm and extend our previous studies demonstrating that the mutagenic potency of 1,2-dibromoethane (DBE) and dibromomethane (DBM) is markedly enhanced (not prevented) in bacteria expressing the O6- alkylguanine-DNA alkyltransferase (ATase) encoded by the Escherichia coli ogt gene. We demonstrate that, in close parallel with mutagenesis, the Ogt ATase sensitizes the bacteria to the lethal effects of these carcinogens, suggesting that one or more of the potentially mutagenic lesions induced by DBE and DBM in the presence of Ogt has additional lethal capacity. We further demonstrate that the sensitization to both lethality and mutagenesis by DBE and DBM is a property shared by other DNA alkyltransferases. This objective was accomplished by quantifying the induction of mutations and lethal events in ogt- ada- E. coli expressing an exogenous bacterial or mammalian ATase from a multicopy plasmid. Mammalian recombinant ATases enhanced the lethal and mutagenic actions of DBE and suppressed the lack of sensitivity of the vector- transformed bacteria to DBM. In most cases the order of effectiveness of the ATases ranked: murine > human > Ogt > rat. Further comparisons included the full-length Ada ATase from E. coli and a truncated Ada version (T-ada) that retains the O6-methylguanine binding domain of the protein. The full-length Ada ATase was effective in enhancing the lethality but not the mutagenicity induced by DBE and DBM. The T-ada ATase provided less sensitization than Ada to lethality by DBE, but of the three bacterial ATases T-ada yielded the highest sensitization to mutagenesis by this compound. T-ada and Ada ATases were in general less effective than the mammalian versions, with the exception of the rat recombinant ATase. The effectiveness of the different mammalian and bacterial ATases in promoting the deleterious actions of dibromoalkanes was compared with the effectiveness of these proteins in suppressing the lethal and mutagenic effects induced by N-nitroso-N-methylurea. The ability to sensitize E. coli to the lethal and mutagenic effects of DBE and DBM seems restricted to DNA alkyltransferase, since overexpression of thioredoxin (Trx) or glutaredoxin (Grx1) in ogt- ada- cells showed no effect, in spite of the reported potential of bioactive dihaloethane- derived species to alkylate Trx.   相似文献   
10.
目的:了解丹参酮ⅡA对神经祖细胞系C17.2的保护作用,探讨其可能的作用机制。方法:本实验于2005年起在广州血液中心器官移植配型中心实验室进行。C17.2祖细胞系由澳大利亚新南威尔士大学解剖教研室David Walsh博士惠赠。将C17.2细胞以1×109L-1的密度接种,用含10%胎牛血清IMDM,37℃、体积分数为0.05CO2、饱和湿度的CO2培养箱培养,接近融合的C17.2细胞用含0.1mmol/LEDTA的胰酶室温消化,按1∶3的比例传代。C17.2细胞以5×107L-1的密度接种于96孔板或25cm2的培养瓶中,用含10%胎牛血清IMDM培养过夜后,加入含4g/L AAPH(水溶性偶氮引发剂2,2'-偶氮二(2-脒基丙烷)二盐酸盐)无血清的IMDM培养基培养建立神经细胞凋亡模型。C17.2细胞以5×103/孔的密度接种于96孔板中,用含10%胎牛血清IMDM培养过夜后,加入含4g/LAAPH无血清的IMDM培养基培养。对照组不加入丹参酮ⅡA,实验组分别加入0.02,0.05,0.1,0.2mg/L丹参酮ⅡA培养8h,噻唑蓝法检测细胞活性:细胞活性的相对值=(实验组吸光度值/对照组吸光度值)×100%,流式细胞仪检测细胞凋亡。结果:①AAPH处理8h后,C17.2细胞被过氧化损害,大多数细胞失去正常的形态,细胞呈圆形,脱落。加入丹参酮ⅡA后,细胞形态基本保持正常,少数细胞呈圆形。②C17.2细胞在IMDM的培养液中,细胞数量是含4g/L AAPH无血清的IMDM培养基条件下的2.5~3倍。浓度为0.02,0.05,0.1mg/L的丹参酮ⅡA对C17.2细胞有保护作用,质量浓度大于0.2mg/L丹参酮ⅡA对C17.2细胞保护作用降低。③AAPH作用前大部分C17.2细胞的线粒体完整,有少量的早期凋亡细胞和凋亡细胞,AAPH作用后凋亡细胞总数、凋亡细胞明显增加。丹参酮ⅡA处理组可以明显减少早期凋亡细胞。结论:在体外丹参酮ⅡA对神经细胞具有抗凋亡的作用,可以保护神经细胞。  相似文献   
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