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排序方式: 共有9438条查询结果,搜索用时 15 毫秒
911.
Issaka Sagara Alassane Dicko Ruth D. Ellis Michael P. Fay Sory I. Diawara Mahamadoun H. Assadou Mahamadou S. Sissoko Mamady Kone Abdoulbaki I. Diallo Renion Saye Merepen A. Guindo Ousmane Kante Mohamed B. Niambele Kazutoyo Miura Gregory E.D. Mullen Mark Pierce Laura B. Martin Amagana Dolo Dapa A. Diallo Ogobara K. Doumbo Louis H. Miller Allan Saul 《Vaccine》2009
A double blind, randomized, controlled Phase 2 clinical trial was conducted to assess the safety, immunogenicity, and biologic impact of the vaccine candidate Apical Membrane Antigen 1-Combination 1 (AMA1-C1), adjuvanted with Alhydrogel®. Participants were healthy children 2–3 years old living in or near the village of Bancoumana, Mali. A total of 300 children received either the study vaccine or the comparator. No impact of vaccination was seen on the primary endpoint, the frequency of parasitemia measured as episodes >3000/μL/day at risk. There was a negative impact of vaccination on the hemoglobin level during clinical malaria, and mean incidence of hemoglobin <8.5 g/dL, in the direction of lower hemoglobin in the children who received AMA1-C1, although these differences were not significant after correction for multiple tests. These differences were not seen in the second year of transmission. 相似文献
912.
Issaka Sagara Ruth D. Ellis Alassane Dicko Mohamed B. Niambele Beh Kamate Ousmane Guindo Mahamadou S. Sissoko Michael P. Fay Merepen A. Guindo Ousmane Kante Renion Saye Kazutoyo Miura Carole Long Gregory E.D. Mullen Mark Pierce Laura B. Martin Kelly Rausch Amagana Dolo Dapa A. Diallo Louis H. Miller Ogobara K. Doumbo 《Vaccine》2009
A double blind, randomized and controlled Phase 1 clinical trial was conducted to assess the safety and immunogenicity in malaria-exposed adults of the Plasmodium falciparum blood stage vaccine candidate Apical Membrane Antigen 1-Combination 1 (AMA1-C1)/Alhydrogel® with and without the novel adjuvant CPG 7909. Participants were healthy adults 18–45 years old living in the village of Donéguébougou, Mali. A total of 24 participants received 2 doses one month apart of either 80 μg AMA1-C1/Alhydrogel® or 80 μg AMA1-C1/Alhydrogel® + 564 μg CPG 7909. The study started in October 2007 and completed follow up in May 2008. Both vaccines were well tolerated, with only mild local adverse events and no systemic adverse events judged related to vaccination. The difference in antibody responses were over 2-fold higher in the group receiving CPG 7909 for all time points after second vaccination and the differences are statistically significant (all p < 0.05). This is the first use of the novel adjuvant CPG 7909 in a malaria-exposed population. 相似文献
913.
Yukiko Miura Akitaka Shibuya Shigeru Adachi Atsuko Takeuchi Takeshi Tsuchihashi Takahide Nakazawa Katsunori Saigenji 《Hepatology research》2008,38(6):546-556
Aim: Recent studies have suggested that an occult hepatitis B virus (HBV) infection negative for HBsAg but positive for HBV-DNA contributes to hepatocellular carcinoma (HCC) development in patients with chronic hepatitis C. Some follow-up studies have suggested the clinical importance of occult HBV infections in HCC development even after interferon (IFN) therapy, but a recent study denies the significance of the impact of occult HBV infection. Focusing on HCC development in patients in whom hepatitis C virus (HCV) eradication by interferon (IFN) therapy had failed, we conducted this study in order to assess the impact of occult HBV infections on HCC development in these patients. Methods: We enrolled 141 patients with chronic hepatitis C (histological stage F2 or F3) who were seropositive for HCV-RNA even after IFN therapy. Serum HBV-DNA was assayed using the real-time polymerase chain reaction. During follow-up, ultrasonography and/or computed tomography (CT) were performed at least every 6 months to monitor HCC development. Results: The cumulative incidence rates of HCC were 8.9%, 25.7% and 53.7% at 5 years, 10 years and 15 years, respectively, after IFN therapy. Multivariate analysis indicated that low platelet counts (<12 x 10(4)/mm(3)), occult HBV infection, high ALT levels (>/=80 IU/L) after IFN therapy and the staging of liver fibrosis were important independent factors affecting the appearance of HCC. Conclusions: Occult HBV was a risk factor for HCC development in patients with chronic hepatitis C in whom HCV eradication had failed. Therefore, patients with chronic hepatitis C with occult HBV should be monitored carefully for HCC after IFN therapy. 相似文献
914.
915.
916.
Sepehr A Mino-Kenudson M Ogawa F Brugge WR Deshpande V Lauwers GY 《The American journal of surgical pathology》2008,32(12):1770-1779
Autoimmune pancreatitis (AIP) shows a unique spectrum of histologic features and commonly presents with an abundant IgG4-positive (IgG4+) plasma cell infiltration. However, differentiating AIP from other mass lesions, particularly pancreatic cancer [invasive ductal carcinoma (IDC)] can be clinically challenging. In this study, we evaluated the validity of IgG4 and IgG immunohistochemistry of ampullary and periampullary tissue for the diagnosis of AIP. Our study group consisted of 14 resected AIP cases with appropriate ampullary sections. Superficial ampullary tissue and "shouldering" duodenal mucosa were evaluated for several histologic variables. Immunohistochemistry for IgG4 and IgG was performed. The number of IgG4 and IgG-positive plasma cells was counted and an IgG4+ to IgG+ plasma cells ratio (IgG4/IgG ratio) was evaluated. A control cohort was composed of IDC (n=30) and chronic pancreatitis (CP) (n=29). Although an overlap was present between the groups, the overall inflammation and number of plasma cells in and around the ampulla was significantly increased in AIP compared with CP and IDC. Furthermore, although there was some overlap in the crude number of IgG4+ plasma cells of the ampullary and duodenal tissue between AIP, IDC, and CP, an IgG4/IgG ratio, especially of the ampulla, seems diagnostically useful in differentiating AIP from other "mass forming" lesions. When a cut-off of 0.10 was applied, the diagnostic sensitivity and specificity of the ampullary IgG4/IgG ratio was 86% and 95%, respectively. In conclusion, evaluation of ampullary histology and IgG4/IgG ratio might be proven beneficial in discriminating AIP from other mass forming pancreatic lesions. 相似文献
917.
Miyakawa S Ishihara S Takada T Miyazaki M Tsukada K Nagino M Kondo S Furuse J Saito H Tsuyuguchi T Kimura F Yoshitomi H Nozawa S Yoshida M Wada K Amano H Miura F;Japanese Association of Biliary Surgery;Japanese Society of Hepato-Biliary-Pancreatic Surgery;Japan Society of Clinical Oncology 《Journal of Hepato-Biliary-Pancreatic Surgery》2008,15(1):7-14
No strategies for the diagnosis and treatment of biliary tract carcinoma have been clearly described. We developed flowcharts
for the diagnosis and treatment of biliary tract carcinoma on the basis of the best clinical evidence. Risk factors for bile
duct carcinoma are a dilated type of pancreaticobiliary maljunction (PBM) and primary sclerosing cholangitis. A nondilated
type of PBM is a risk factor for gallbladder carcinoma. Symptoms that may indicate biliary tract carcinoma are jaundice and
pain in the upper right area of the abdomen. The first step of diagnosis is to carry out blood biochemistry tests and ultrasonography
(US) of the abdomen. The second step of diagnosis is to find the local extension of the carcinoma by means of computed tomography
(CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), percutaneous transhepatic cholangiography
(PTC), and endoscopic retrograde cholangiopancreatography (ERCP). Because resection is the only way to completely cure biliary
tract carcinoma, the indications for resection are determined first. In patients with resectable disease, the indications
for biliary drainage or portal vein embolization (PVE) are checked. In those with nonresectable disease, biliary stenting,
chemotherapy, radiotherapy, and/or best supportive care is selected. 相似文献
918.
Mataki N Kikuchi K Kawai T Higashiyama M Okada Y Kurihara C Hokari R Kawaguchi A Nagao S Kondo T Itoh K Miyakawa H Miura S 《The American journal of gastroenterology》2007,102(2):302-312
OBJECTIVES: PD-L1 (also B7-H1) and PD-L2 (also B7-DC) are ligands for programmed death-1 (PD-1), which is a member of the CD28/B7 superfamily of costimulatory molecules and plays an inhibitory role on the periphery. Impaired regulation of this system may cause disruption to self-tolerance leading to autoimmunity; however, the role of these molecules in the liver is unknown. Therefore, we examined the expression of PD-1, PD-L1, and PD-L2 in the liver in autoimmune liver diseases. METHODS: We examined the liver expression of these molecules in autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) with no previous medical treatment using immunohistochemical staining and real-time PCR, and compared with chronic hepatitis type C (CHC) as a control. RESULTS: Although PD-1, PD-L1, and PD-L2 were expressed in the liver in AIH, PBC, as well as CHC, the expressions were relatively lower in PBC. In AIH, despite more severe inflammation than in CHC, the expression of these molecules was not greater than in CHC, and when compared with the relative expression of PD-L1, PD-L2 was lower in AIH. PD-L1 and PD-L2 expressions were well correlated with the level of IFN-gamma; however, relatively decreased induction for PD-L1 and PD-L2 by IFN-gamma was observed in AIH or PBC than in CHC. CONCLUSION: Modulation of PD-1/PD-L1 and PD-L2 systems may play a role in the development of autoimmune liver diseases. 相似文献
919.
Miura T Nishida H Kawai A Maeda T Kurosawa H Koyanagi H 《General thoracic and cardiovascular surgery》2008,56(10):521-525
A 33-year-old-man had severe secondary pulmonary hypertension due to perivalvular leakage at the aortic and mitral positions after aortic and mitral valve replacement. Preoperative cardiac catheterization revealed pulmonary artery pressure of 105/45 mmHg and pulmonary vascular resistance of 929 dynes.s.cm(-5) To save the patient, we performed aortic and mitral valve re-replacement, and tricuspid annuloplasty. After surgery, selective pulmonary vasodilators, beraprost sodium, inhaled nitric oxide, and intravenous prostaglandin (PG) I(2) were administered because of persistent severe pulmonary hypertension. Cardiac catheterization on postoperative day 58 showed that the pulmonary artery pressure and pulmonary vascular resistance had decreased to 40/20 mmHg and 87.7 dynes x s x cm(-5), respectively The simultaneous use of inhaled nitric oxide, intravenous PGI(2), and oral beraprost sodium might be useful for treating postoperative persistent pulmonary hypertension. 相似文献
920.