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991.
Isolated granulomatous inflammation of the appendix is extremely rare, and its etiology is still unknown. Thus, differentiating between idiopathic granulomatous appendicitis and isolated appendiceal Crohn's disease is difficult. We report a case of idiopathic granulomatous appendicitis with long-term follow-up after surgery. A 26-year-old woman was referred to our hospital for investigation of persistent right lower abdominal pain. Abdominal computed tomography showed a mass, suggesting an inflammatory tumor around the appendix; thus, we suspected subacute appendicitis and performed laparoscopically assisted ileocecal resection. Histological examination of the resected specimen revealed several noncaseous epithelioid granulomas in the wall of the appendix, but no foreign bodies, obstructing lesions, or parasites. Stains for acid-fast bacillus and fungi, and serology for yersinia were all negative. The patient has been followed up for 9 years and remains asymptomatic. This clinical course suggests that her isolated granulomatous appendicitis was idiopathic granulomatous appendicitis unrelated to Crohn's disease.  相似文献   
992.
Background We investigated factors affecting 5-year survival in patients undergoing hepatic resection for colorectal cancer metastases, including events long after initial hepatectomy. Although retrospective studies have demonstrated survival benefit of hepatectomy for metastatic colorectal cancer, few have included sufficient 5-year survivors to identify survival-related factors throughout the clinical course. Methods We divided 156 patients with hepatectomy for colorectal cancer metastases into 5-year survivors (n = 64) and patients dying before 5 years after hepatectomy (n = 92). Clinicopathologic data were compared retrospectively with respect to long-term outcome. Results By multivariate analysis, large liver tumors (adjusted relative risk, 2.029; P = .011), short tumor doubling time (1.809; P = .026), and origin from poorly differentiated primary adenocarcinoma (12.632; P = .001) compromised survival, whereas initial treatment-related variables did not. Although no difference was seen in initial treatment-related variables between 5-year survivors with recurrence after hepatectomy and patients dying before 5 years, repeat surgery was used more frequently in survivors (P < .001), typically with adjuvant chemotherapy. Conclusions Reoperations for each recurrence of metastases, followed by additional chemotherapy, frequently resulted in long survival.  相似文献   
993.
Introduction Down-regulation of apoptosis genes has been implicated in the development and progression of malignant melanoma. We used cDNA microarray to evaluate pro-apoptotic gene expression comparing normal skin to melanoma (thin and thick), nodal disease and distant metastases. Methods Twenty-eight specimens including skin (n = 1), thin melanoma (n = 6), thick melanoma (n = 7), nodal disease (n = 6), and distant metastases (n = 8), were harvested at the time of resection from 16 individuals. RNA was isolated and microarray analysis utilizing the Affymetrix GeneChip (54,000 genetic elements, U133A+B... levels) was performed. Mean level of expression was calculated for each gene within a sample group. Expression profiles were then compared between tissue groups. Student’s t-test was used to determine variance in expression between groups. Results We reviewed the expression of 54,000 genetic elements, of which 2,015 were found to have significantly altered expression. This represents 1,602 genes. Twenty-two pro-apoptotic genes were found to be down-regulated when compared to normal skin. Overall reduction was evaluated comparing normal skin to metastases with a range of 3.31–64.04-fold-decrease. When comparing the tissue types sequentially, the greatest fold-decrease in gene expression occurred when comparing skin to all melanomas (thin and thick) (p = 0.011). Subset analysis comparing normal skin to thin melanoma or thick melanoma, revealed the greatest component of overall reduction at the transition from thin to thick lesions (p = 0.003). Conclusion Sequential down-regulation of pro-apoptotic genes is associated with the progression of malignant melanoma. The greatest fold-decrease occurs in the transformation from thin to thick lesions.  相似文献   
994.
Objective Gallstone bacteria provide a reservoir for biliary infections. Slime production facilitates adherence, whereas β-glucuronidase and phospholipase generate colonization surface. These factors facilitate gallstone formation, but their influence on infection severity is unknown. Methods Two hundred ninety-two patients were studied. Gallstones, bile, and blood (as applicable) were cultured. Bacteria were tested for β-glucuronidase/phospholipase production and quantitative slime production. Infection severity was correlated with bacterial factors. Results Bacteria were present in 43% of cases, 13% with bacteremia. Severe infections correlated directly with β-glucuronidase/phospholipase (55% with vs 13% without, P < 0.0001), but inversely with slime production (55 vs 8%, slime <75 or >75, P = 0.008). Low slime production and β-glucuronidase/phospholipase production were additive: Severe infections were present in 76% with both, but 10% with either or none (P < 0.0001). β-Glucuronidase/phospholipase production facilitated bactibilia (86% with vs 62% without, P = 0.03). Slime production was 19 (±8) vs 50 (±10) for bacteria that did or did not cause bacteremia (P = 0.004). No bacteria with slime >75 demonstrated bacteremia. Conclusions Bacteria-laden gallstones are biofilms whose characteristics influence illness severity. Factors creating colonization surface (β-glucuronidase/phospholipase) facilitated bacteremia and severe infections; but abundant slime production, while facilitating colonization, inhibited detachment and cholangiovenous reflux. This shows how properties of the gallstone biofilm determine the severity of the associated illness. Presented at the annual meeting of the Society for Surgery of the Alimentary Tract, held May 20–24, 2006 in Los Angeles, California.  相似文献   
995.
Background and Aim Results after curative liver resection in hepatocellular carcinoma are unsatisfactory with regard to high postoperative intrahepatic recurrence and liver failure. This study evaluates telomerase activity in liver with and without tumor as a predictor of recurrence and survival. Materials and Methods Liver tissue with and without tumor from 53 hepatocellular carcinoma patients receiving curative resection during the period of 1998–2000 was used for detecting telomerase activity by PCR-ELISA. Clinicopathological data were compared to identify predictors of recurrence and survival. Results Telomerase activity was detected in 98% of liver tissue with tumor and 70% liver tissue without. Telomerase activity in cancerous liver correlated significantly with HCV infection (P = 0.012) and cirrhotic change in liver parenchyma (P = 0.006). Telomerase activity in non-cancerous liver correlated with high serum AFP level (P = 0.002). The telomerase activity of liver tissue with and without tumor is significant higher in patients with recurrence than in those without recurrence, 413.7 ± 100.5 versus 110.8 ± 32.7, P = 0.006, and 34.7 ± 14.2 versus 4.2 ± 1.4, P = 0.039. Recurrence could be predicted by abnormally high tumor telomerase activity (P = 0.026) or by advanced TNM stage (P = 0.001). TNM stage or high serum ALT level could predict multinodular intrahepatic recurrence (P = 0.028 and P = 0.030). High serum AFP combined with high telomerase activity in liver without tumor had a significant ability to predict poor survival (OR: 11.19, CI: 1.95–64.12, P = 0.007). Conclusion Tumor telomerase is an independent predictor of recurrence. Simultaneous high remnant liver telomerase and high serum AFP is a strong negative predictor of survival.  相似文献   
996.
997.
Background Aging of the midface is complex and poorly understood. Changes occur not only in the facial soft tissues, but also in the underlying bony structure. Computed tomography (CT) imaging was used for investigating characteristics of the bony orbit and the anterior wall of the maxilla in patients of different ages and genders. Methods Facial CT scans were performed for 62 patients ranging in age from 21 to 70 years, who were divided into three age groups: 2130 years, 41–50 years, and 61–70 years. Patients also were grouped by gender. The lengths of the orbital roof and floor and the angle of the anterior wall of the maxilla were recorded on parasagittal images through the midline of the orbit for each patient. Results The lengths of the orbital roof and floor at their midpoints showed no significant differences between the age groups. When grouped by gender, the lengths were found to be statistically longer for males than for females. The angle between the anterior maxillary wall and the orbital floor was found to have a statistically significant decrease with advancing age among both sexes. Conclusion Bony changes occur in the skeleton of the midcheek with advancing age for both males and females. The anterior maxillary wall retrudes in relation to the bony orbit, which maintains a fixed anteroposterior dimension at its midpoint. These changes should be considered in addressing the aging midface.  相似文献   
998.
Introduction Postoperative treatment for colorectal cancer depends on tumor stage as defined by the International Union Against Cancer (UICC). Adjuvant chemotherapy is not recommended in patients without lymph node involvement (UICC stages I and II). As many as 20–30% of these patients, however, will develop recurrence. Aims and objectives We conducted this study to determine the presence of disseminated tumor cells in the lymph nodes by quantitative real-time polymerase chain reaction (QRT-PCR) for cytokeratin 20 (CK20) in an attempt to provide supplementary information compared to histopathological findings. Materials and methods Using a standard QRT-PCR assay, we examined primary tumors and 391 lymph nodes from 31 patients with completely resected colorectal cancer. Results Of the 31 primary tumors, 29 were positive for CK20 by QRT-PCR. Discussion An examination of the lymph nodes from the 29 patients with CK20-positive primary tumors revealed that 35 (92.1% sensitivity) of the 38 histopathologically positive lymph nodes and 54 (16.7%) of the 324 histopathologically negative lymph nodes were positive by molecular analysis. CK20 expression was detected in 10 (100%) of 10 patients with a histopathologically positive lymph node status (pN1). In 9 (47.4%) of 19 patients with negative histopathological results (pN0), we detected a CK20 mRNA signal in at least one lymph node. Whereas eight patients with histopathologically negative lymph nodes could be upstaged on the basis of the molecular findings, no patient would be downstaged. Conclusion Our results suggest that QRT-PCR for CK20 is a useful tool for the quantitative detection of micrometastases in the regional lymph nodes. We introduce a standardized procedure that integrates a molecular diagnostic technique in the clinical staging.  相似文献   
999.
Opinion statement Atherosclerotic narrowing of the proximal internal carotid artery is an important mechanism in ischemic stroke. Optimal medical management of internal carotid stenosis includes antiplatelet agent and statin administration, blood pressure reduction, weight control, and smoking cessation. Decisions regarding the use of invasive procedures to treat carotid disease—specifically carotid endarterectomy and carotid angioplasty and stenting—must weigh the long-term risk reduction in ipsilateral ischemic stroke against the immediate intervention risks. Clinical trials evaluating the benefits of carotid endarterectomy were conducted before widespread use of statins and newer blood pressure-lowering agents such as angiotensin-receptor blockers; it is unclear what impact this may have had on trial results. Regardless, carotid endarterectomy is clearly superior to medical therapy for patients with symptomatic severe stenosis. Conversely, the benefit from endarterectomy is muted in individuals with symptomatic moderate stenosis or asymptomatic stenosis, and decisions regarding surgical intervention must incorporate surgeon proficiency and patient comorbidity. Currently, there is a lack of evidence to support the use of carotid artery angioplasty and stenting in the routine management of carotid disease. Selected patients with severe symptomatic stenosis for whom endarterectomy cannot be safely performed may still benefit from endovascular management. However, it is unlikely that asymptomatic patients or symptomatic patients with moderate stenosis considered at high risk for endarterectomy would benefit from any intervention.  相似文献   
1000.
In this study, we compared the effects of vitamin K2 menatetrenone on bone mechanical properties in rats fed a low-magnesium (Mg) diet. In addition, the mechanism of bone quality was examined using Fourier transform infrared imaging (FTIRI). Thirty 4-week-old male Wistar rats were divided into three groups: intact, low-Mg-control, and low-Mg-MK-4 groups. Rats in the low-Mg groups were given a diet containing 6 mg/100 g Mg (intact, 90 mg/100 g). After an 8-week-treatment, the cortical bone mineral content (CtBMC), outer perimeter, and endo perimeter of the femoral diaphysis in the low-Mg-control group were significantly higher, while the maximum load (ML) and elastic modulus (EM) were 81% and 50% of those in the intact group, respectively (respectively, P < 0.05). In the low-Mg-MK-4 group, ML and EM were significantly higher than in the low-Mg-control group (P < 0.05), with no differences in CtBMC. The mineral/matrix ratios for the periosteal and central regions in the low-Mg-control group were 162% and 120% of those in the intact group (both, P < 0.05), respectively. MK-4 significantly inhibited these increases (P < 0.05). We found that the mineral/matrix ratios for the periosteal region of the femoral diaphysis were negatively correlated with EM, suggesting that an increase in the mineral/matrix ratio may be involved in the reduction of EM and that MK-4 may improve EM by improving the mineral/matrix ratio.  相似文献   
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