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AIM: The aim of this study was to evaluate the practice of colonoscopy and sigmoidoscopy in France in 2000. METHODS: A prospective study was conducted in November 2000 using questionnaires sent to all gastroenterologists practicing in France (N=2858) who were asked to reply to items concerning colonoscopies and sigmoidoscopies performed on two workdays chosen in advance. The response rate was 32.8%. Data were extrapolated to establish estimates for the entire year. RESULTS: An estimated 894000 colonoscopies and 115320 sigmoidoscopies were performed in 2000. Single-use material was used in 22.1% of the procedures. Indications for endoscopy were mainly hematochezia (21.6%), gastrointestinal symptoms (35%) and surveillance of patients with a history of previous polypectomy (15%). Colorectal cancer screening was the indication for 20% of colonoscopies. Abnormal findings were reported for 54.8% of the endoscopies (polyps for 287218 procedures and cancer for 32799). Failure was noted in 4.9% of colonoscopies. The complication rate was 0.48%. Most polyps were adenomas (64.4%) or hyperplasic polyps (28.1%). The overall estimated number of colonoscopies with polypectomy was 224133. CONCLUSION: In 2000 there was an increased rate of colonoscopy for colorectal cancer screening (20%) but an overall decrease (2.5%) in the total number of colonoscopies compared to 1999. Abnormal findings were disclosed by 54.8% of the procedures. Extrapolation from these data indicates that colonoscopic screening enabled the diagnosis of 32799 colorectal cancers.  相似文献   
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Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.  相似文献   
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BackgroundReference values for cardiac magnetic resonance imaging (cMRI) in children and young adults are scarce. This leads to risk stratification of patients with congenital heart diseases being based on volumes indexed to body surface area (BSA). We aimed to produce cMRI Z score equations for ventricular volumes in children and young adults and to test whether indexing to BSA resulted in an incorrect assessment of ventricular dilation according to sex, body composition, and growth.MethodsWe retrospectively included 372 subjects aged < 26 years with either normal hearts or conditions with no impact on ventricular volumes (reference group), and 205 subjects with repaired tetralogy of Fallot (TOF) aged < 26 years. We generated Z score equations by means of multivariable regression modelling. Right ventricular dilation was assessed with the use of Z scores and compared with indexing to BSA in TOF subjects.ResultsVentricular volume Z scores were independent from age, sex, and anthropometric measurements, although volumes indexed to BSA showed significant residual association with sex and body size. In TOF subjects, indexing overestimated dilation in growing children and underestimated dilation in female compared with male subjects, and in overweight compared with lean subjects.ConclusionsIndexed ventricular volumes measured with cMRI did not completely adjust for body size and resulted in a differential error in the assessment of ventricular dilation according to sex and body size. Our proposed Z score equations solved this problem. Future studies should evaluate if ventricular volumes expressed as Z scores have a better prognostic value than volumes indexed to BSA.  相似文献   
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Chronic total coronary occlusions were more frequently crossed using the Crosswire as a primary guidewire strategy than with the conventional strategy. This strategy resulted in a lower number of guidewires being used, a trend toward shorter procedural and fluoroscopy times, and decreased use of contrast media.  相似文献   
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Endoscopic treatment of pancreatico-biliary malignancies   总被引:8,自引:0,他引:8  
Biliary obstructions, due to pancreatic cancer and cholangiocarcinoma, have an ominous prognosis. At the time of diagnosis, most patients are beyond any curative treatment. Palliative therapies, such as transhepatic biliary drainage, bypass surgery, and endoscopy, have an established role in the management of such patients. Endoscopic retrograde cholangio-pancreatography (ERCP) plays a key role, allowing diagnosis, collection of cytologic and bioptic specimens, and insertion of large-bore biliary stents. The major drawback of plastic stents is the high rate of clogging, requiring frequent stent exchange. In the 1990s, self-expanding metal stents (SEMS) were developed and randomized studies have shown their superiority over plastic stents. SEMS can be successfully used in patients with hilar tumors. Duodenal obstruction due to biliopancreatic neoplasms can also be managed endoscopically. ERCP can be performed on an outpatient basis in selected patients, reducing costs related to hospitalization. A team approach is mandatory to obtain the best results.  相似文献   
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