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651.
AIM: TO determine whether -1195 A→G and/or -765 G→C polymorphisms in Cyclooxygenase-2 CCOX-2) may have a risk modifying effect on the development of esophageal carcinoma in a Dutch Caucasian population. METHODS: Two study groups were recruited, 252 patients with esophageal carcinoma and 240 healthy controls, matched for race, age, gender and recruiting area. DNA was isolated from whole blood and used for genotyping. PCR products were digested with restriction enzymes and products were analyzed by agarose gel electrophoresis. Odds ratios (OR) and 95% confidence intervals (CI) were estimated. RESULTS: The distribution of the -1195A→G polymorphism was significantly different in esophageal cancer patients compared to controls. The -1195 GG genotype resulted in a higher risk of developing esophageal adenocarcinoma (OR = 3.85, 95% CI: 1.45-10.3) compared with the -1195AA genotype as a reference. The -765 G→C genotype distribution was not different between the two groups. The GG/ GG haplotype was present more often in esophageal adenocarcinoma patients than in controls (OR = 3.45, 95% CI: 1.24-9.58; with AG/AG as a reference). The same trends were observed in patients with squamous cell carcinomas, however, the results did not reach statistical significance. CONCLUSION: Presence of the COX-2 -1195 GG genotype and of the GG/GG haplotype may result in a higher risk of developing esophageal carcinoma.  相似文献   
652.
AIM: TO determine the possible modulating effect of the COX-2 polymorphisms, -765G→C and -1195A→G, on the risk of colorectal cancer (CRC) in a Dutch population. METHODS: This case-control study includes 326 patients with CRC and 369 age- and gender-matched controls. Genotypes of the COX-2 polymorphisms -7dEG→C and -1195A→G were determined by polymerase chain reaction-based restriction fragment length polymorphism. COX-2 genotypes and haplotypes were analyzed and odds ratios with 95% confidence intervals were estimated by logistic regression. RESULTS: The -765GG genotype was associated with an increased risk of developing CRC (OR, 1.45; 95% CI, 1.03-2.04). No significant difference was observed in the genotype distribution of the -1195A→G polymorphism between patients and controls. The GG/AC haplotype was present significantly less often in patients than in controls (OR 0.44; 95% CI, 0.22-0.85). When the AC, AG and GG haplotypes were investigated separately, the AC haplotype showed a tendency to be less frequent in patients than in controls (OR(AG/AC) 0.78; 95% CI, 0.57-1.06). CONCLUSION: The -765GG genotype is associated with an increased risk of developing CRC and the G6/ AC haplotype seems to protect against CRC. These findings suggest a modulating role for the COX-2 polymorphisms -765G→C and -1195A→G in the development of CRC in a Dutch population.  相似文献   
653.

Background

To potentially improve outcomes in pancreatic resection, robot-assisted pancreatic surgery has been introduced. This technique has possible advantages over laparoscopic surgery, such as its affordance of three-dimensional vision and increased freedom of movement of instruments. A systematic review was performed to assess the safety and feasibility of robot-assisted pancreatic surgery.

Methods

The literature published up to 30 September 2011 was systematically reviewed, with no restrictions on publication date. Studies reporting on over five patients were included. Animal studies, studies not reporting morbidity and mortality, review articles and conference abstracts were excluded. Data were extracted and weighted means were calculated.

Results

A total of 499 studies were screened, after which eight cohort studies reporting on a total of 251 patients undergoing robot-assisted pancreatic surgery were retained for analysis. Weighted mean operation time was 404 ± 102 min (510 ± 107 min for pancreatoduodenectomy only). The rate of conversion was 11.0% (16.4% for pancreatoduodenectomy only). Overall morbidity was 30.7% (n = 77), most frequently involving pancreatic fistulae (n = 46). Mortality was 1.6%. Negative surgical margins were obtained in 92.9% of patients. The rate of spleen preservation in distal pancreatectomy was 87.1%.

Conclusions

Robot-assisted pancreatic surgery seems to be safe and feasible in selected patients and, in left-sided resections, may increase the rate of spleen preservation. Randomized studies should compare the respective outcomes of robot-assisted, laparoscopic and open pancreatic surgery.  相似文献   
654.
Previous studies have demonstrated that significant hematologic improvement occurs in the majority of patients with hairy cell leukemia (HCL) treated with partially purified or recombinant interferon (IFN). Fifty-three patients received IFN alfa-2b for at least 3 months in a dose of 2 X 10(6) U/m2 subcutaneously thrice weekly. Of the 49 patients evaluable for response (at least 6 months of IFN therapy), there were ten complete responses and 29 partial responses for a total response rate of 80%. The peripheral blood counts and bone marrow continued to improve over the course of a full year of therapy. IFN was well tolerated, with no patients discontinuing therapy because of toxicity. Transient myelosuppression occurred in most patients during the first 1 to 2 months of therapy, occasionally precipitating a transfusion requirement. After IFN treatment was discontinued, there was a marked decrease in normal marrow elements and a relative increase in marrow hairy cells. This was associated with a transient increase in normal elements in the peripheral blood. Only one of 24 patients followed after receiving IFN for a median of 8.5 months (range, 3 to 16 months) has required further therapy. We conclude that low-dose IFN alfa-2b is highly effective in advanced HCL; responding patients should be treated for at least 1 year. The decision to initiate a second course of IFN therapy should be based primarily on peripheral blood counts and the clinical status of the patient rather than on the bone marrow.  相似文献   
655.
This study identifies the risk factors for hepatitis B virus (HBV) and hepatitis C virus (HCV) and measures the prevalence of hepatitis B surface antigen (HBsAg) and antibody to hepatitis C (anti-HCV) in the general population of Jakarta. A population-based sample of 985 people aged 15 and above was surveyed. Risk factors were identified through questionnaires and home visits. Serum was analysed for HBsAg, antibody to hepatitis B surface antigen (anti-HBs), anti-HCV, aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The seroprevalence was: 4.0% (39/985) for HBsAg, 17.2% (170/985) for anti-HBs, and 3.9% (38/985) for anti-HCV. The risk factors for hepatitis B and hepatitis C infection had little in common. Low socioeconomic status was a strong risk factor for HBsAg (adjusted odds ratio (OR) 18.09; 95% confidence interval (CI) 2.35–139.50). In addition, the Chinese group has 2.97 higher risk of having HBV infection compared with the Malayan ethnic group (adjusted OR 2.97; 95% CI 1.22–7.83). There was moderate positive trend between family size and risk of HBsAg positivity (P= 0.130). Age over 50 (adjusted OR 14.72; 95% CI 4.35–49.89) and history of transfusion were significant risk factors for hepatitis C (adjusted OR 3.03; 95% CI 1.25–7.33). Hepatitis B and hepatitis C infections have different risk factors in Jakarta, a high risk in population for both diseases. Hepatitis B transmission is associated with low socioeconomic status, Chinese ethnic group and large family size, while hepatitis C is associated with an older age and a history of transfusions.  相似文献   
656.
Purpose: This study was conducted to determine the abrasive effect of a porcelain and an Ni–Cr alloy on the wear of human enamel, and the influence of a carbonated beverage on the rate of wear. Materials and Methods: Tooth specimens were prepared by embedding 48 freshly extracted mandibular first premolars in acrylic. Twenty‐four of these specimens were abraded against Ni–Cr, and the remaining 24 against porcelain in artificial saliva and carbonated beverage media, respectively (n = 12), on a specially designed abrasive testing machine at a constant load of 40 N with 6 mm amplitude for 15,000 cycles. The cusp heights of the tooth specimens were measured both before and after abrasion using a profile projector. The abraded cast specimens were subjected to profilometry for computing the surface roughness; the abrading media was subjected to atomic absorption spectrophotometry for analyzing Ni and Cr ion levels. Data obtained were statistically analyzed. Results: Porcelain specimens in a medium of carbonated beverage caused the highest wear of tooth specimens. The lowest wear of tooth specimens was Ni–Cr specimens in artificial saliva medium. Carbonated beverage caused significantly higher wear of tooth specimens when abraded against Ni–Cr and porcelain specimens than did artificial saliva. The mean quantitative surface roughness of porcelain specimens was significantly higher than that of Ni–Cr specimens, irrespective of the medium in which abrasion testing was conducted. There was no statistically significant difference between the concentrations of Ni ions released in artificial saliva and carbonated beverage media. Also, there was no statistically significant difference between the concentrations of Cr ions released in artificial saliva and carbonated beverage media. Conclusions: The wear of human enamel was significantly higher in the presence of carbonated beverage than artificial saliva and against porcelain when compared with Ni–Cr. The surface roughness of porcelain in the presence of carbonated beverage was found to be highest, and the release of Ni and Cr was not affected by carbonated beverage.  相似文献   
657.
Lorenz  HM; Lagoo  AS; Hardy  KJ 《Blood》1994,83(7):1862-1870
We recently reported that cross-linking the leukocyte common antigen (CD45) can rapidly induce aggregation of human peripheral blood mononuclear cells via lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) interactions. Herein, we have examined both T-cell--monocyte cellular interactions and the molecular signaling that are involved in this phenomenon. Experiments using highly purified T lymphocytes showed that CD45-induced aggregation requires the presence of both T cells and monocytes. Cross- linking CD45 only on T lymphocytes, but not on monocytes, initiated cellular clustering after reconstituting to the respective untreated cell type. By several criteria, CD45-induced clustering of T cells to autologous monocytes was shown to be Fc-receptor--independent. When comparing intracellular signaling in leukocyte aggregation induced by CD45 cross-linking versus phorbol myristate-12-13-acetate (PMA) treatment, the former was found to be fivefold to 10-fold more sensitive to H-8, a reagent that effectively blocks cAMP- and cGMP- dependent protein kinases. On the other hand, reagents that increase intracellular cAMP levels (eg, dbcAMP, forskolin, and IBMX), protein kinase C (PKC) inhibitors (eg, staurosporine), and tyrosine kinase inhibitors (eg, herbimycin A and genistein) all readily inhibited PMA- induced, but not CD45 monoclonal antibody-induced, aggregation. We conclude that cross-linking the leukocyte common antigen on T cells induces LFA-1--/ICAM-1--dependent T-cell--monocyte aggregation through a unique signaling pathway independent of PKC, which involves instead cAMP-/cGMP-dependent protein kinases.  相似文献   
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