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991.
992.
Radiofrequency ablation(RFA)of pancreatic neoplasms is restricted to locally advanced,non-resectable but nonmetastatic tumors.RFA of pancreatic tumors is nowadays an ultrasound-guided procedure performed during laparotomy in open surgery.Intraoperative ultrasound covers the mandatory role of staging,evaluation of feasibility,guidance and monitoring of the procedure.Different types of needle can be used.The first aim in the evaluation of RFA as a treatment for locally advanced pancreatic ductal adenocarcinom...  相似文献   
993.
AIM:To investigate the effects of malnutrition and refeeding on the P2X2 receptor,nitric oxide synthase(NOS),calretinin,calbindin and choline acetyltransferase(ChAT) in neurons of the rat ileum.METHODS:We analyzed the co-localization,numbers and sizes of P2X2-expressing neurons in relation to NOS-immunoreactive(IR),calbindin-IR,ChAT-IR,and calretinin-IR neurons of the myenteric and submucosal plexus.The experimental groups consisted of:(1) rats maintained on normal feed throughout pregnancy until 42 d post-...  相似文献   
994.
AIM:To examine the detection rate of viable Mycobacterium avium subspecies paratuberculosis(MAP) in patients with inflammatory bowel disease [Crohn’s disease(CD) and ulcerative colitis(UC)].METHODS:Thirty patients with CD(15 with at least one NOD2/CARD15 mutation),29 with UC,and 10 with no inflammatory bowel disease(IBD).were tested for MAP by polymerase chain reaction(specific IS900 fragment) and blood culture.RESULTS:MAP DNA was detected in all original blood samples and 8-wk blood cultures(CD,UC and non-IBD).Positive MAP DNA status was confirmed by dot blot assays.All 69 cultures were negative by acid-fast Ziehl-Neelsen staining.Viable MAP,in spheroplast form,was isolated from the 18-mo blood cultures of all 30 CD patients,one UC patient,and none of the non-IBD controls.No association was found between positive MAP cultures and use of immunosuppressive drugs or CDassociated single nucleotide polymorphisms.CONCLUSION:MAP is widely present in our area and MAP DNA can be recovered from the blood of CD,UC and non-IBD patients.However,MAP spheroplasts were only found in CD patients.  相似文献   
995.

Background  

According to previous observations, basal gastric acid secretion is downregulated by phosphoinositol-3-(PI3)-kinase, phosphoinositide-dependent kinase (PDK1), and protein kinase B (PKBβ/Akt2) signaling. PKB/Akt phosphorylates glycogen synthase kinase GSK3. The present study explored whether PKB/Akt-dependent GSK3-phosphorylation modifies gastric acid secretion.  相似文献   
996.
American Trypanosomiasis or Chagas disease (CD) is a neglected disease that affects Latin American people worldwide. Two old antiparasitic drugs, benznidazole and nifurtimox, are currently used for specific CD treatment with limited efficacy in chronic infections and frequent side effects. New drugs are needed for patients with chronic CD as well as for immunosuppressed patients, for whom the risk of reactivation is life-threatening. We describe a case of chronic CD and systemic lupus erythematosus (SLE) that required immunosuppression to control the autoimmune process. It was found that benznidazole induced a reduction, but not an elimination, of circulating Trypanosoma cruzi levels, whereas subsequent treatment with posaconazole led to a successful resolution of the infection, despite the maintenance of immunosuppressive therapy.  相似文献   
997.
Epidemiologic studies have adapted to the genomics era by forming large international consortia to overcome issues of large data volume and small sample size. Whereas both cohort and well-conducted case-control studies can inform disease risk from genetic susceptibility, cohort studies offer the additional advantages of assessing lifestyle and environmental exposure-disease time sequences often over a life course. Consortium involvement poses several logistical and ethical issues to investigators, some of which are unique to cohort studies, including the challenge to harmonize prospectively collected lifestyle and environmental exposures validly across individual studies. An open forum to discuss the opportunities and challenges of large-scale cohorts and their consortia was held in June 2009 in Banff, Canada, and is summarized in this report.  相似文献   
998.

Purpose

To study the association between occupational exposure to metals including chromium, cadmium, nickel, and arsenic compounds, within a population-based study design, while adjusting for confounding factors.

Methods

A population-based lung cancer case?Ccontrol study in Central/Eastern Europe and UK was conducted in 1998?C2003, including 2,853 cases and 3,104 controls. Exposure to 70 occupational agents was assessed by local expert-teams for all subjects. Odds ratios (OR) for exposure to dust and fumes/mist of chromium, nickel, cadmium, arsenic, as well as inorganic pigment dust and inorganic acid mist, were adjusting for smoking, age, center, sex, and exposure to other occupational agents including the metals under study.

Results

Exposure to arsenic (prevalence = 1.4%) was associated with an increased lung cancer risk ((OR) 1.65, 95% confidence interval (95% CI):1.05?C2.58). For chromium dust (prevalence = 4.8%, OR: 1.25, 95% CI: 0.95?C1.65), a linear upward trend for duration and cumulative exposure was observed. A weak association was observed for exposure to cadmium fumes (prevalence = 1.8%, OR: 1.19, 95% CI: 0.77?C1.82), which was strongest for the highest category of cumulative exposure (OR: 2.04, 95% CI: 1.07?C3.90). No increased risk was observed for inorganic acid mist, inorganic pigment dust, or nickel, after adjustment for other metals. An independent effect of nickel cannot be excluded, due to its collinearity with chromium exposure.

Conclusions

Occupational exposure to metals is an important risk factor for lung cancer. Although the strongest risk was observed for arsenic, exposure to chromium dust was most important in terms of attributable risk due to its high prevalence.  相似文献   
999.

Objective

Folate is involved in the one-carbon metabolism that plays an essential role in the synthesis, repair, and methylation of DNA. We examined whether child??s germline genetic variation in the folate pathway is associated with childhood acute lymphoblastic leukemia (ALL), and whether periconception maternal folate and alcohol intake modify the risk.

Methods

Seventy-six single nucleotide polymorphisms (SNPs), including 66 haplotype-tagging SNPs in 10 genes (CBS, DHFR, FOLH1, MTHFD1, MTHFR, MTR, MTRR, SHMT1, SLC19A1, and TYMS), were genotyped in 377 ALL cases and 448 controls. Log-additive associations between genotypes and ALL risk were adjusted for age, sex, Hispanic ethnicity (when appropriate), and maternal race.

Results

Single and haplotype SNPs analyses showed statistically significant associations between SNPs located in (or adjacent to) CBS, MTRR, TYMS/ENOFS, and childhood ALL. Many regions of CBS were associated with childhood ALL in Hispanics and non-Hispanics (p < 0.01). Levels of maternal folate intake modified associations with SNPs in CBS, MTRR, and TYMS.

Conclusion

Our data suggest the importance of genetic variability in the folate pathway and childhood ALL risk.  相似文献   
1000.
Although the association for esophageal cancer with tobacco smoking and alcohol drinking has been well established, the risk appears to be less strong in China. To provide more evidence on the effect of smoking and alcohol consumption with esophageal cancer in China, particularly among Chinese women, a population-based case-control study has been conducted in Jiangsu, China, from 2003 to 2007. A total of 1,520 cases and 3,879 controls were recruited. Unconditional multivariate logistic regression analysis was applied. Results showed that the odds ratio (OR) and confidence interval (CI) for ever smoking and alcohol drinking were 1.57 (95% CI: 1.34-1.83) and 1.50 (95% CI: 1.29-1.74). Dose-response relationships were observed with increased intensity and longer duration of smoking/drinking. Risk of smoking and alcohol drinking at the highest joint level was 7.32 (95% CI: 4.58-11.7), when compared to those never smoked and never drank alcohol. Stratifying by genders, smoking and alcohol drinking increased the risk among men with an OR of 1.74 (95% CI: 1.44-2.09) and 1.76 (95% CI: 1.48-2.09); however, neither smoking nor alcohol consumption showed a significant association among women. In conclusion, smoking and alcohol drinking were associated with esophageal cancer risk among Chinese men, but not among Chinese women.  相似文献   
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