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991.
Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a new disease entity characterized by limited mouth opening due to contracture of the masticatory muscles resulting from hyperplasia of tendons and aponeuroses. The other clinical feature is that the face of the patient with this disease displays a square mandible configuration. Muscle relaxants provide no relief for the limited mouth-opening ability. Anesthesiologists need to suspect difficult airway when patients have limited mouth opening with square mandible configuration. MMTAH can therefore be a possible cause of difficult intubation.  相似文献   
992.
Commercial fisheries exert high mortalities on the stocks they exploit, and the consequent selection pressure leads to fisheries-induced evolution of growth rate, age and size at maturation, and reproductive output. Productivity and yields may decline as a result, but little is known about the rate at which such changes are likely to occur. Fisheries-induced evolution of exploited populations has recently become a subject of concern for policy makers, fisheries managers, and the general public, with prominent calls for mitigating management action. We make a general evolutionary impact assessment of fisheries by calculating the expected rate of fisheries-induced evolution and the consequent changes in yield. Rates of evolution are expected to be ≈0.1–0.6% per year, and the consequent reductions in fisheries yield are <0.7% per year. These rates are at least a factor of 5 lower than published values based on experiments and analyses of population time series, and we explain why the published rates may be overestimates. Dealing with evolutionary effects of fishing is less urgent than reducing the direct detrimental effects of overfishing on exploited stocks and on their marine ecosystems.  相似文献   
993.
994.
Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn disease (CD), is a disorder characterized by diffuse inflammation of the gastrointestinal tract. The immune response and inflammation are mediated by polyunsaturated fatty acids and influenced by dietary fats and lipid metabolism. This study examined the qualitative and quantitative fat intake of IBD patients and healthy controls on plasma phospholipid and erythrocyte membrane phospholipid (EMP) fatty acid content. Measurement of the fatty acid composition of plasma phospholipid and EMP were performed in 29 UC patients, 20 CD patients, and 31 healthy controls. Anthropometric characteristics and data on dietary intake were also collected. We observed significantly lower lipid intake in UC and CD patients vs controls. The UC and CD patients had significantly higher levels of linoleic acid in their EMP than did controls. There were no significant differences in the levels of n-3 polyunsaturated fatty acids, but there were significantly higher levels of the n-6 in the EMP of UC and CD patients compared with controls. The significant differences persisted after the data were adjusted for potential confounders and lipid intake. Higher levels of linoleic acids and n-6 fatty acids, which are involved in production of proinflammatory mediators, were found in IBD patients compared with controls, thereby implicating n-6 fatty acids in the pathophysiology of the disease.  相似文献   
995.
996.
PURPOSE: To identify novel endometrial cancer-specific methylation markers and to determine their association with clinicopathologic variables and survival outcomes. EXPERIMENTAL DESIGN: Differential methylation hybridization analysis (DMH) was done for 20 endometrioid endometrial cancers using normal endometrial DNA as a reference control. Combined bisulfite restriction analysis (COBRA) was used to verify methylation of sequences identified by DMH. Bisulfite sequencing was undertaken to further define CpG island methylation and to confirm the reliability of the COBRA. The methylation status of newly identified markers and the MLH1 promoter was evaluated by COBRA in a large series of endometrioid (n=361) and non-endometrioid uterine cancers (n=23). RESULTS: DMH and COBRA identified two CpG islands methylated in tumors but not in normal DNAs: SESN3 (PY2B4) and TITF1 (SC77F6/154). Bisulfite sequencing showed dense methylation of the CpG islands and confirmed the COBRA assays. SESN3 and TITF1 were methylated in 20% and 70% of endometrioid tumors, respectively. MLH1 methylation was seen in 28% of the tumors. TITF1 and SESN3 methylation was highly associated with MLH1 methylation (P<0.0001). SESN3 and TITF1 were methylated in endometrioid and non-endometrioid tumors, whereas MLH1 methylation was restricted to endometrioid tumors. Methylation at these markers was not associated with survival outcomes. CONCLUSIONS: The 5' CpG islands for SESN3 and TITF1 are novel cancer-specific methylation markers. Methylation at these loci is strongly associated with aberrant MLH1 methylation in endometrial cancers. SESN3, TITF1 and MLH1 methylation did not predict overall survival or disease-free survival in this large cohort of patients with endometrioid endometrial cancer.  相似文献   
997.
998.
The Wilms' tumor gene WT1 is overexpressed in most of human leukemias regardless of disease subtypes. To characterize the expression pattern of WT1 during normal and neoplastic hematopoiesis, we generated a knock-in reporter green fluorescent protein (GFP) mouse (WT1(GFP/+)) and assayed for WT1 expression in normal and leukemic hematopoietic cells. In normal hematopoietic cells, WT1 was expressed in none of the long-term (LT) hematopoietic stem cells (HSC) and very few (<1%) of the multipotent progenitor cells. In contrast, in murine leukemias induced by acute myeloid leukemia 1 (AML1)/ETO+TEL/PDGFbetaR or BCR/ABL, WT1 was expressed in 40.5 or 38.9% of immature c-kit(+)lin(-)Sca-1(+) (KLS) cells, which contained a subset, but not all, of transplantable leukemic stem cells (LSCs). WT1 expression was minimal in normal fetal liver HSCs and mobilized HSCs, both of which are stimulated for proliferation. In addition, overexpression of WT1 in HSCs did not result in proliferation or expansion of HSCs and their progeny in vivo. Thus, the mechanism by which expansion of WT1-expressing cells occurs in leukemia remains unclear. Nevertheless, our results demonstrate that the WT1(GFP/+) mouse is a powerful tool for analyzing WT1-expressing cells, and they highlight the potential of WT1, as a specific therapeutic target that is expressed in LSCs but not in normal HSCs.  相似文献   
999.
Gastric carcinosarcoma often presents with an elevated lesion or increased thickness of the stomach wall. Histological diagnosis is achieved using conventional hematoxylin and eosin staining to confirm the coexistence of both epithelial and mesenchymal elements. We report a case of gastric carcinosarcoma presenting as a large mass in the epigastric region. Specimens obtained by endoscopic biopsy and surgical excision showed diffuse proliferation of atypical cells in sheet formation. No mucus production or glandular structures were apparent, but immunoreactivity for both epithelial and mesenchymal markers was noted. These findings led to a definitive diagnosis of gastric carcinosarcoma. Immunohistochemical analysis is useful for the early diagnosis and treatment of gastric carcinosarcoma.  相似文献   
1000.
We herein present a case of recurrence of gastric cancer in the jejunal pouch after total gastrectomy in a 74-year-old man. He had a history of two operations for gastric cancer. The second operation was a completion gastrectomy with jejunal pouch reconstruction and regional lymphadenectomy, for gastric cancer in the cardia of the remnant stomach, performed 2 years and 9 months before the present admission. A follow-up endoscopy showed three elevated tumors along the suture lines in the jejunal pouch in the upper digestive tract. Resection of the jejunal pouch was performed. Gross pathological examination revealed elevated lesions along the staple suture lines in the jejunal pouch. Histopathologically, moderately differentiated tubular adenocarcinoma involving the muscular layer, without lymphatic metastases, was recognized. Recurrence of gastric cancer in the jejunal pouch after resection is rare. We suggest that implantation of exfoliated cancer cells gave rise to the recurrence of tumors on the suture line in this patient. We also review two cases of gastric cancer in the jejunal pouch after resection previously described in the literature.  相似文献   
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