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1.
Lower gastrointestinal bleeding is a frequent cause of hospitalization, particularly in the elderly, and its incidence appears to be on the rise. Colonic diverticular bleeding is the most common form of lower gastrointestinal bleeding and is responsible for 30–40 % of bleeding episodes. Risk factors associated with diverticular bleeding include obesity, hypertension, anticoagulants, diabetes mellitus, and ischemic heart disease. Recent studies have suggested a relationship between usage of non-steroidal anti-inflammatory drugs (NSAIDs) and colonic diverticular bleeding; however, most studies were small with wide confidence intervals. We identified studies by searching the PubMed and Scopus databases (from inception through 31 December 2012) and by searching bibliographies of relevant articles. Summary relative risks (RRs) with 95 % confidence intervals (CIs) were calculated with fixed-effects and random-effects models. A total of six studies (five case–control studies and one cohort study) met inclusion criteria for analysis. Non-aspirin NSAIDs (NANSAIDs) and aspirin were associated with an increased risk of colonic diverticular bleeding (summary RR = 2.48, 95 % CI 1.86–3.31), with moderate heterogeneity among these studies (P heterogeneity = 0.11, I 2 = 44.4 %). Stratification to evaluate the heterogeneity found that both NANSAIDs (summary RR = 2.24, 95 % CI 1.63–3.09; 5 studies) and aspirin (summary RR = 1.73; 95 % CI 1.31–2.30; 3 studies) were associated with the risk of diverticular bleeding. Aspirin/NANSAIDs use was strongly and consistently associated with an increased risk of colonic diverticular bleeding. Further studies are needed to stratify individuals at risk of diverticular bleeding associated with the use of these agents.  相似文献   
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Three-dimensional imaging with MRI is a useful method for neurosurgical simulations. As in our previous study, we have constructed three-dimensional surface anatomical scanning (3D-SAS) from the data of contrast enhanced 3D fast spoiled gradient recalled acquisition in the steady state (3D-FSPGR) sequence. Using this technique, it is possible to generate 3D images from the data of only one acquisition, without using the fusion function. In our previous study, we did not compare the 3D images with the operative views at surgery. In the present study, two radiologists and one neurosurgeon assessed the 3D images in comparison with the operative views. There were problems in some cases, including unclear cortical sulci owing to brain swelling, lack of depiction of the cortical veins owing to meningeal enhancement, inadequate distinction between pial veins and meningeal veins, and so forth. However, in the majority of cases, 3D-SAS with 3D-FSPGR was able to demonstrate good anatomical conformity with the operative views, indicating the clinical usefulness of this technique.  相似文献   
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Nasopharyngeal transmission of Streptococcus pneumoniae was evaluated among 23 siblings with acute otitis media (AOM). Restriction fragment length polymorphism revealed that the nasopharyngeal strains were identical between siblings in 12 of 13 clusters of AOM experienced in 11 families. This study demonstrated person-to-person transmission of S. pneumoniae, especially drug-resistant strains, among siblings with AOM.  相似文献   
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Streptococcus pneumoniae is a leading causative pathogen responsible for various types of bacterial infectious diseases in children. The aim of this study was to evaluate the protection conferred against fatal pneumococcal infections during infancy by maternal intranasal immunization with pneumococcal surface protein A (PspA). Four-week-old female BALB/c mice were immunized with PspA mixed with, or without, cholera toxin B (CTB) intranasally twice a week for 3 weeks. After the final immunization, they were mated with male mice to obtain offspring. Offspring at 10 days old were intraperitoneally inoculated with a pneumococcus strain, TIGR4, serotype 4. After the infections their survival periods were monitored. Anti-PspA-specific IgG antibody was induced in sera and breast milk at birth and maintained for 14 days during nursing periods in the PspA-immunized mother mice. At birth, offspring delivered from PspA-immunized mother mice had levels of anti-PspA-specific IgG antibody in sera same to those in their mothers on the day of birth. The survival times to death of offspring delivered from PspA-immunized mother mice after systemic fatal pneumococcal infections were significantly extended compared to those of controls. These findings suggest that maternal intranasal immunization with PspA could be an attractive procedure to employ against pneumococcal infections in early childhood.  相似文献   
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Pneumococcal phase variation of 37 middle ear and 31 nasopharyngeal isolates obtained from children with acute otitis media was examined in the absence of intervening culture. The fraction of the opaque colonies was significantly higher in middle ear isolates than in nasopharyngeal isolates. The difference is probably the result of the pneumococci adapting to differential selective environments.  相似文献   
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Kita T  Hata Y  Miura M  Kawahara S  Nakao S  Ishibashi T 《Diabetes》2007,56(5):1421-1428
Connective tissue growth factor (CTGF) level is elevated in eyes with proliferative vitreoretinal diseases, such as proliferative diabetic retinopathy and proliferative vitreoretinopathy (PVR), as we previously reported, but its functional characteristics on vitreoretinal cells are yet to be clarified. In this study, we demonstrated a growth-promoting effect of CTGF on cultured hyalocytes and bovine retinal pigment epithelial cells (BRPEs) with the induction of p44/p42 mitogen-activated protein kinase phosphorylation and [(3)H]thymidine incorporation. CTGF also stimulated the synthesis of fibronectin by hyalocytes and BRPEs without significant effect on collagen gel contraction by these cells. On the other hand, CTGF had no direct effects on the proliferation, migration, or in vitro tube formation by vascular endothelial cells. Nevertheless, CTGF promoted vascular endothelial growth factor (VEGF) gene expression by hyalocytes and BRPEs. Although the concentrations of both CTGF and VEGF in the human vitreous samples with proliferative vitreoretinal diseases were elevated, there was no significant correlation between these concentrations. These findings indicate that CTGF appears to be involved in the formation of proliferative membranes without direct regulation of their cicatricial contraction in the pathogenesis of proliferative vitreoretinal diseases. Whereas CTGF might have no direct effects or minimal effects, if any, on retinal neovascularization, it is possible that CTGF has indirect effects by modulating the expression of VEGF.  相似文献   
9.
Focal nodular hyperplasia (FNH) of the liver is a relatively uncommon pathology, with only 68 cases having been documented to date in Japan. Here, we describe an interesting case; the patient had two concurrent lesions of FNH in segments three (S3) and five (S5), respectively. The two lesions differed from each other in their behavior on various radiographic imagings, i.e., computed tomography, magnetic resonance imaging, and hepatic angiography, leading to a misdiagnosis of hepatocellular carcinoma for the S3 lesion. The patient underwent left lateral hepatic resection, along with excision of the S5 lesion. Histological examination confirmed that these two lesions were FNH. Retrospective assessment of the correlation between the radiographic imagings and the morphological architecture suggested that the architectural differences between the two lesions (i.e., that, in the S3 lesion, the central scar was more developed than in the S5 lesion and was more prominent in the periphery than in the central area of the lesion) had contributed to the misdiagnosis.  相似文献   
10.
We believe that regional vascular occlusion of the liver is more effective for the treatment of hepatocellular carcinoma (HCC) than transcatheter arterial embolization or percutaneous ethanol injection. We report a patient with HCC in whom regional vascular occlusion by means of radiological intervention was successfully performed. A 68-year-old man was admitted to our hospital because of a HCC measuring 2 cm in diameter in segment VIII (S8). For treatment, we initially performed subsegmental vascular occlusion by simultaneous transcatheter arterial embolization and percutaneous transhepatic portal-venous embolization. Both the arterio-and the portograms taken immediately after the procedure demonstrated the lack of arterial and portal blood supply to S8. Subsequent evaluation of the liver by computed tomography and magnetic resonance imaging suggested that S8 had become completely infarcted and the segment appeared wedge-shaped. This finding was histologically confirmed when hepatic subsegmentectomy was performed 5 weeks later. The results in this patients confirmed the results reported by Nakao et al. in 1986 (Hepatocellular carcinoma: Combined hepatic arterial and portal venous embolizationRadiology 161:303–307) suggesting that regional vascular occlusion of the liver was safe and that the effectiveness was comparable to that of hepatic resection.  相似文献   
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