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991.
992.
MicroRNAs have become recognized as key players in the development of cancer. They are a family of small non-coding RNAs that can negatively regulate the expression of cancer-related genes by sequence-selective targeting of mRNAs, leading to either mRNA degradation or translational repression. Lung cancer is the leading cause of cancer-related death worldwide with a substantially low survival rate. MicroRNAs have been confirmed to play roles in lung cancer development, epithelial-mesenchymal transition and response to therapy. They are also being studied for their future use as diagnostic and prognostic biomarkers and as potential therapeutic targets. In this review we focus on the role of dysregulated microRNA expression in lung tumorigenesis. We also discuss the role of microRNAs in therapeutic resistance and as biomarkers. We further look into the progress made and challenges remaining in using microRNAs for therapy in lung cancer.  相似文献   
993.
AIM:To determine whether magnified observation of short-segment Barrett’s esophagus(BE)is useful for the detection of specialized intestinal metaplasia(SIM).METHODS:Thirty patients with suspected short-segment BE underwent magnifying endoscopy up to×80.The magnified images were analyzed with respect to their pit-patterns,which were simultaneously classified into five epithelial types[Ⅰ(small round),Ⅱ(straight),Ⅲ(long oval),Ⅳ(tubular),Ⅴ(villous)]by Endo’s classification.Then,a 0.5%solution of methylene blue(MB)was sprayed over columnar mucosa.The patterns of the magnified image and MB staining were analyzed.Biopsies were obtained from the regions previously observed by magnifying endoscopy and MB chromoendoscopy.RESULTS:Three of five patients with a typeⅤ(villous)epithelial pattern had SIM,whereas 21 patients with a non-typeⅤepithelial patterns did not have SIM.The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of pit-patterns in detecting SIM were 100%,91.3%,92.3%,60%and100%,respectively(P=0.004).Three of the 12 patients with positive MB staining had SIM,whereas 14patients with negative MB staining did not have SIM.The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of MB staining in detecting SIM were 100%,60.9%,65.4%,25%and100%,respectively(P=0.085).The specificity and accuracy of pit-pattern evaluation were significantly superior compared with MB staining for detecting SIM by comparison with the exact McNemar’s test(P=0.0391).CONCLUSION:The magnified observation of a shortsegment BE according to the mucosal pattern and its classification can be predictive of SIM.  相似文献   
994.
AIM:To evaluate the effect of gastrectomy on diabetes control in patients with type 2 diabetes mellitus and early gastric cancer.METHODS:Data from 64 patients with early gastric cancer and type 2 diabetes mellitus were prospectively collected.All patients underwent curative gastrectomy(36 subtotal gastrectomy with gastroduodenostomy,16subtotal gastrectomy with gastrojejunostomy,12 total gastrectomy)and their physical and laboratory data were evaluated before and 3,6 and 12 mo after surgery.RESULTS:Fasting blood glucose(FBS),HbA1c,insulin,C-peptide,and homeostasis model assessment-estimated insulin resistance were significantly improved 3mo after surgery,regardless of operation type,and the significant improvement in all measured values,except HbA1c,was sustained up to 12 mo postoperatively.Approximately 3.1%of patients stopped diabetes medication and had HbA1c<6.0%and FBS<126 mg/dL.54.7%of patients decreased their medication,and had reduced FBS or HbA1c.In multivariate analysis,good diabetic control was not associated with operation type,but was associated with diabetes duration.CONCLUSION:Diabetes improved in more than 50%of patients during the first year after gastric cancer surgery.The degree of diabetes control was related to diabetes duration.  相似文献   
995.
Colorectal carcinomas(CRCs)are frequently found in industrialized countries and lead to a high incidence of malignancy-related mortality.Defined by histomorphological features,CRCs and their pre-invasive lesions are quite heterogeneous.The underlying molecular mechanisms include genomic instability,genomic mutation of tumor suppressor genes or oncogenes,epigenetic changes,and the microRNA network.The molecular mechanisms are guided by repeated clonal selections.The genotype-to-phenotype relation is assumed to be the great challenge of cancer research and the development of effective targeted therapies.At present a strong genotype-to-phenotype relation is characterized only for a minority of CRCs.Consequently,the molecular characterization of CRCs is essential to interpret histological patterns and to identify prognostic groups as well as patients for targeted therapy.  相似文献   
996.

Purpose  

The purpose of this study was to evaluate the feasibility and efficacy of laparoscopic lymphadenectomy in patients with gynecologic malignancies and improve upon the existing published data regarding laparoscopic lymphadenectomy.  相似文献   
997.
998.
Venous complications in patients with acute pancreatitis typically occur as a form of splenic, portal, or superior mesenteric vein thrombosis and have been detected more frequently in recent reports. Although a well-organized protocol for the treatment of venous thrombosis has not been established, anticoagulation therapy is commonly recommended. A 73-year-old man was diagnosed with acute progressive portal vein thrombosis associated with acute pancreatitis. After one month of anticoagulation therapy, the patient developed severe hematemesis. With endoscopy and an abdominal computed tomography scan, hemorrhages in the pancreatic pseudocyst, which was ruptured into the duodenal bulb, were confirmed. After conservative treatment, the patient was stabilized. While the rupture of a pseudocyst into the surrounding viscera is a well-known phenomenon, spontaneous rupture into the duodenum is rare. Moreover, no reports of upper gastrointestinal bleeding caused by pseudocyst rupture in patients under anticoagulation therapy for venous thrombosis associated with acute pancreatitis have been published. Herein, we report a unique case of massive upper gastrointestinal bleeding due to pancreatic pseudocyst rupture into the duodenum, which developed during anticoagulation therapy for portal vein thrombosis associated with acute pancreatitis.  相似文献   
999.
During the 2006-2007 winter season in South Korea, several outbreaks of highly pathogenic avian influenza virus (H5N1) were confirmed among domestic poultry and in migratory bird habitats. Phylogenetic analysis showed that all isolates were closely related and that all belong to the A/bar-headed goose/Qinghai/5/2005-like lineage rather than the A/chicken/Korea/ES/2003-like lineage.  相似文献   
1000.
We investigated the effects of fermentation filtrates from Rubus coreanus on the function of the male reproductive system. We performed an ex vivo study to determine if the candidate compounds relax isolated New Zealand white rabbit corpus cavernosum, which were precontracted by phenylephrine (5 x 10(-5) M). The results reveal that the filtrates of the reddish-purple (FRRC) and green (FGRC) R. coreanus exerted concentration-dependent relaxing effects, leading to median effective concentrations of 4.53 mg/mL and >10 mg/mL, respectively. For the in vivo study, male ICR mice were orally administered FRRC or FGRC (100 or 500 mg/kg) for 28 days, and the reproductive organ weights, serum testosterone level, cauda epididymal sperm counts, and motility were analyzed. Both the FRRC and FGRC had no significant effect on the reproductive organ weights; however, FRRC (100 or 500 mg/kg) enhanced testosterone levels and especially sperm counts at the higher dose (500 mg/kg). In comparison, FGRC increased hormone levels and sperm counts at a relatively low dose (100 mg/kg). In summary, it is proposed that the crude fermentation filtrates of ripe R. coreanus have positive effects on the function of the male reproductive system by triggering a penile erection, enhancing serum testosterone levels, and increasing epididymal sperm counts.  相似文献   
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