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Pancreas divisum (P.D.) is a congenital anatomic variant, characterized by the nonunion of dorsal and ventral pancreatic ducts. A 20 years old man followed for 8 years with reccurent abdominal pain and relapsing acute pancreatitis develope chronic calcific pancreatitis. He was diagnosed with P.D. on endoscopic retrograde pancreatography and operative pancreatography. The patient was treated with longitudinal pancreatico-jejunostomy (PUESTOW-GILLESBY procedure). His pain resolved following surgical drainage of the pancreatic duct. Evaluation of the clinical course of this patient and critical review of other such cases in the literature support the role of compromised ductal drainage of the pancreas in the pathogenesis of chronic pancreatitis in P.D.  相似文献   
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BACKGROUND: Lung cancer has the highest mortality-rate per cancer, with an overall 5-year survival <15%. Several non-randomized studies pointed out the high sensitivity of low dose computed tomography (LDCT) to detect early stage lung cancer. In France, Depiscan, a pilot RCT of LDCT versus chest X-ray (CXR), started on October 2002 to determine the feasibility of enrollment by general practitioners (GPs), investigations and diagnostic procedures by university hospital radiologists and multidisciplinary teams, data management by centralized clinical research assistants, and anticipate the future management of a large national trial. METHODS: GPs and occupational physicians (OPs) selected and enrolled 1000 subjects in 1 year. Eligible subjects were asymptomatic males or females aged 50-75 years with a current or former cigarette smoking history of >/=15 cigarettes per day for at least 20 years (former smokers having quit <15 years prior to enrollment). Based to randomization, annual LDCT or CXR screenings were planned at baseline and annually for 2 years. RESULTS: Between October 2002 and December 2004, 765 subjects were enrolled by 89 out of the 232 participating GPs and OPs. Complete clinical and imaging baseline data were available for 621 individuals out of the 765 enrolled, due to 144 noncompliant subjects who withdrew their consent. At least one nodule was detected in 152 out of 336 subjects (45.2%) in the LDCT screening, versus 21 out of 285 subjects (7.4%) in the CXR screening arm. Eight lung cancers were detected in the LDCT arm and one in the CXR arm. DISCUSSION: This pilot trial allows estimating that non-calcified nodules are 10 [6.36-17.07] times more often detected from LDCT than from CXR. However enrollment by GPs was more difficult than expected with 41% active investigators and a high rate (19%) of noncompliant patients. This experience speaks to the need for a high level of GPs formation and a large, coordinated clinical research team in such a trial. Trial registration number: 02526.  相似文献   
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Epidemiological and toxicological studies have provided evidence that accidentally inhaled nanosize ultrafine particles can induce chronic or acute health damage. MRI, being noninvasive, is able to assess the biodistribution and clearance of magnetically labeled nanoparticles induced by instillation or inhalation. We report 3He and proton MRI follow-up of lung, liver, spleen, and kidney distribution of USPIO (ultrasmall superparamagnetic iron oxide) in a rat model. The sensitivity of the imaging technique to various concentrations of instilled magnetite suspension was first assessed in vivo (n=12). A 2-week longitudinal imaging study was then performed on animals (n=7) instilled with a 0.5 mg magnetite solution. Hypointense and void signal regions associated with intrapulmonary USPIO were observed in the 3He ventilation images throughout the study, whereas no USPIO-related proton signal intensity changes were found. Intrapulmonary magnetite nanoparticle confinement was confirmed by ex vivo iron assay and histological analysis. This study demonstrates that combined 3He and proton MRI enables noninvasive assessment of the distribution and clearance of magnetically labeled instilled nanoparticles.  相似文献   
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In order to clear some aspects of HCV infection, we evaluated quarterly HCV markers by a RIBA 1 test (antigens c100-3 and 5.1.1) and monthly transaminases (ALT and AST) for 14 months in 89 HBsAg-free maintenance hemodialysis patients (MHP), and we retrospectively examined clinical records until the start of hemodialysis treatment. At the start of the study, 16 patients showed HCV antibodies (HCV+) and 73 were antibody-free (HCV-). 39 subjects of the staff were also examined. No HCV+ patient showed seroconversion, 10 showed irregular or persistent elevation of AST and ALT. In the retrospective evaluation 14 patients suffered from acute hepatitis (AH). Only 3 cases showed temporal relation with blood transfusions. In 1 case a 36-month temporary normalization of transaminases was noticed. 3 HCV-patients showed seroconversion (1 during AH), 13 showed severe or moderate elevations of transaminases. In the retrospective evaluation, 6 patients suffered from AH. All subjects of the staff were HCV- and showed no seroconversion or changes of transaminases. At the end of the study, we performed a RIBA 2 test containing the HCV antigens c100-3, 5.1.1, c22-3 and c33c. The 6 patients who suffered from AH showed at least 1 positivity for new proteins. Most of AH in MHP are likely due to HCV infection; besides transfusions, cross-infection during the dialytic procedure may be responsible for many cases of HCV infection; long-term normalization of transaminases may not secure against infectivity.  相似文献   
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Inflammatory bowel diseases(IBDs) are chronic disorders of modern society, requiring management strategies aimed at prolonging an active life and establishing the exact etiology and pathogenesis.These idiopathic diseases have environmental, genetic,immunologic, inflammatory, and oxidative stress components. On the one hand, recent advances have shown that abnormal immune reactions against the microorganisms of the intestinal flora are responsible for the inflammation in genetically susceptible individuals. On the other hand, in addition to T helper cell-type(Th) 1 and Th2 immune responses,other subsets of T cells, namely regulatory T cells and Th17 maintained by IL-23 are likely to develop IBD. IL-23 acts on innate immune system members and also facilitates the expansion and maintenance of Th17 cells. The IL-17/IL-23 axis is relevant in IBD pathogenesis both in human and experimental studies. Novel biomarkers of IBD could be calprotectin,microRNAs, and serum proinflammatory cytokines.An efficient strategy for IBD therapy is represented by the combination of IL-17 A and IL-17 F in acute IL-17 A knockout TNBS-induced colitis, and also definite decrease of the inflammatory process in IL-17 F knockout, DSS-induced colitis have been observed.Studying the correlation between innate and adaptive immune systems, we hope to obtain a focused reviewin order to facilitate future approaches aimed at elucidating the immunological mechanisms that control gut inflammation.  相似文献   
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