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991.
992.
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   
993.
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   
994.
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   
995.
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   
996.
Background Interleukin (IL)-6, cyclooxygenase (COX)-2, and monocyte chemoattractant protein (MCP)-1 contribute to renal injury. The promoter regions of these genes contain CCAAT/enhancer-binding protein (C/EBP)-binding sites. In this study, we investigated the role of C/EBP-δ in mesangial cells (MCs). Methods In an in vivo study, anti-Thy 1.1 glomerulonephritis rats were generated and C/EBP-δ, IL-6, COX-2, and MCP-1 expressions were assessed by immunohistochemistry. In an in vitro study, cultured MCs were transfected with non-silencing (NS) short interfering RNA (siRNA) or C/EBP-δ siRNA. Subsequently, after stimulation with IL-1β, C/EBP-δ, IL-6, COX-2, and MCP-1 mRNA expression levels were evaluated using real-time polymerase chain reaction (PCR). IL-6 concentration in the culture medium was determined by enzyme-linked immunosorbent assay. In addition, cell proliferative activity against IL-1β or platelet-derived growth factor-BB was assessed by bromodeoxyuridine incorporation. Results In the in vivo study, C/EBP-δ, IL-6, COX-2, and MCP-1 were expressed in the mesangial region of anti-Thy 1.1 glomerulonephritis rats on day 1. In the in vitro study, IL-1β increased C/EBP-δ mRNA levels in NS siRNA-transfected MCs (7.3-fold), but no increase was evident in C/EBP-δ siRNA-transfected MCs. IL-6, COX-2, and MCP-1 mRNA levels in C/EBP-δ siRNA-transfected MCs were all lower than those in NS siRNA-transfected MCs (decreases of 57.7%, 85.7%, and 69.3%, respectively). The IL-6 concentration in the culture medium from C/EBP-δ siRNA transfected MCs (7.37 ± 4.3 pg/ml) was also lower than that in the culture medium from NS siRNA-transfected MCs (25.2 ± 3.4 pg/ml). Cell proliferative activity in C/EBP-δ siRNA-transfected MCs was lower than that in NS siRNA transfected MCs. Conclusions C/EBP-δ was induced in the mesangial region during the early stages of anti-Thy1.1 glomerulonephritis. C/EBP-δ contributes to inflammatory gene expression and MC proliferation.  相似文献   
997.
A 58-year-old woman underwent laparoscopy-assisted transverse colectomy for transverse colon cancer. On postoperative day 7, she experienced sudden abdominal pain accompanied by vomiting and fever. Computed tomography showed a small bowel obstruction caused by an internal hernia. Laparotomy revealed an internal hernia through the mesenteric defect at the anastomotic colonic stumps, which had not been closed in the previous operation. Almost the entire small bowel protruding through the mesenteric defect was found in the omental bursa. We resected part of the jejunal loop, which was strangulated and congested by an adherent band. Our experience suggests that if the mesenteric defect is relatively small, it should be closed completely during laparoscopy-assisted colectomy; however, more studies are required to determine the indications for closure of the mesenteric defect to prevent this complication.  相似文献   
998.
Objectives Centchroman (Ormeloxifene) is a novel non-steroidal, selective antiestrogen. Because of its selective antiestrogen action, centchroman has been used for treatment of mastalgia and fibroadenoma. Materials and Methods Benign breast disease patients up to 35 years of age attending our surgery outpatient department from August 2003 to September 2004 and fulfilling the inclusion criterion were included in this study. They were started on centchroman 30 mg on alternate days for a period of 3 months and were followed up for 6 months. Results were recorded as per clinical examination, visual analog scale (VAS) for pain, and ultrasonography for breast lump size. Results A total of 60 patients were included in this pilot study, 42 (70%) of whom had mastalgia with or without nodularity, and 18 (30%) had fibroadenoma. Noncyclical pain was recorded in 38 patients (90%), and cyclical pain was recorded in only 4 (10%) patients. A VAS score of 10 was recorded by 33 (80%) patients (severe pain), and the remaining 9 patients (20%) had VAS scores from 7 to 10. Fibroadenoma size ranged from 1.5 to 5 cm., single or multiple in one or both breasts. There was a good response in the mastalgia group, with a decrease in the VAS scoring from 10 to 3 in 90 % of the patients in the first week. Almost all of the patients were painless at the end of one month, with complete disappearance of the nodularity. In the fibroadenoma group there was a mixed response, with complete disappearence in 40%, partial regression in 20%, and no response at all in the remaining 40%. There were very few side effects. Conclusions Centchroman is a safe nonsteroidal drug for the treatment of mastalgia and fibroadenoma. It has shown good results in mastalgia and is a safe drug as compared to the drugs of choice used at present (danazole and bromocriptine). Further randomized studies are in progress and are needed to determine its definitive role in this patient group. Presented at the BSI Prize Session, International Surgical Week “ISW2005,” 41st World Congress of Surgery of ISS/SIC, 21–25 August 2005, Durban, South Africa  相似文献   
999.
Fifteen skeletally immature patients with double major adolescent idiopathic scoliosis with large lumbar curves and notable L4 and L5 coronal plane obliquity were retrospectively studied. Seven patients who underwent anterior release and fusion of the lumbar curve with segmental anterior instrumentation and subsequent posterior instrumentation ending at L3 were compared with eight patients treated with anterior release and fusion without anterior instrumentation followed by posterior instrumentation to L3 or L4. At 4.5 years follow-up (range 2.5-7 years), curve correction, coronal balance and fusion rate were not statistically different between the two groups; however, the group with anterior instrumentation had improved coronal plane, near normalangulation in the distal unfused segment compared with the group without anterior instrumentation. In cases involving severe lumbar curvatures in the context of double major scoliosis, when as a first stage anterior release is chosen, the addition of instrumentation appears to restore normal coronal alignment of the distal unfused lumbar segment, and may in certain cases save a level compared with traditional fusions to L4.  相似文献   
1000.
Peptic ulcer in the excluded segment of a gastric bypass has been reported in the literature in only 17 cases.We report a 54-year-old woman with a perforated duodenal ulcer, who had undergone laparoscopic Roux-en-Y gastric bypass surgery for morbid obesity 15 months previously. She was successfully treated by a laparoscopic repair of the perforated duodenal ulcer.  相似文献   
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