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91.
3-Allyl-5-substituted 2-thiohydantoins (ATH-amino acids) derived from allyl isothiocyanate and amino acids can inhibit the mutagenicity of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in the Salmonella assay. In this report, we studied possible mechanisms for the inhibition using rat liver S9 in assays for ethoxyresorufin O-deethylase (EROD), a marker activity for cytochrome P450 1A (CYP1A), which activates heterocyclic amines, and the Salmonella assays with the direct-acting mutagen 2-hydroxyamino-3-methylimidazo[4,5-f]quinoline (N-hydroxy-IQ). Quantitative analysis of ATH-amino acids and IQ during incubation with rat liver S9 fraction by HPLC showed that ATH-amino acids could act as S9-inhibitors, thereby inhibiting metabolic activation of IQ. Among the tested ATH-amino acids, ATH-Phe, ATH-Trp, ATH-Leu and ATH-Val showed a dose-dependent inhibition of EROD activity. ATH-Gly, ATH-Glu, and ATH-Asp behaved as blocking agents toward N-hydroxy-IQ, but exhibited no inhibition of EROD activity.  相似文献   
92.
We studied 867 junior high school children and administered a questionnaire documenting allergic symptoms and environmental variables, and measured Immunoglobulin E serum levels and the immunoglobulin G titers of serum antibody to microflora. A total of 716 subjects were ultimately used for statistics; those with at least two of the following allergic symptoms: asthma, rhinitis, eczema, or food allergy, showed significantly higher IgG titers to Bactroides vulgatus than other groups. This finding suggests that a species of the Bacteroides genus of the intestinal microflora tends to affect the gut issues, but further studies are needed to clarify this.  相似文献   
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Neovascularization of the outer membrane plays a critical role in the development and enlargement of chronic subdural hematomas (CSHs) and vascular endothelial growth factor (VEGF) may promote their progression. However, the precise mechanisms remain to be determined. We focused on the signaling pathway upstream of VEGF, transforming growth factor β (TGF-β), and activin receptor-like kinase 1 (ALK-1) to identify the mechanisms underlying the neovascularization of the outer membrane of CSH. Retrospective comparative study was conducted on 15 consecutive patients diagnosed as CSH with burr-hole drainage. Dura and the outer membrane were collected. We immunohistochemically examined the expression of VEGF, integrin-α, TGF-β, and ALK-1 on the outer membrane and dura of CSH and compared our findings with control samples and the signal intensity of hematomas on computed tomography (CT) scans. VEGF and integrin-α expression was markedly up-regulated in both the dura and outer membrane of CSH, the expression of TGF-β and ALK-1 in the dura was slightly increased in the dura and markedly up-regulated in the outer membrane. There was no significant correlation between their expression and CT density. Here we first report the expression of TGF-β and ALK-1 in the outer membrane and dura mater of CSH. We suggest that the TGF-β–ALK-1 pathway and VEGF affect neovascularization and the progression of CSH.  相似文献   
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Emphysematous cholecystitis is a rare variant of acute cholecystitis with a high mortality rate.The combination of emphysematous cholecystitis and pneumoperitoneum is also rare.We herein describe a case of emphysematous cholecystitis with massive gas in the abdominal cavity.A 77-year-old male presented with epigastric pain and lassitude lasting for one week.A computed tomography scan demonstrated massive gas in the abdominal cavity.Gas was also detectable inside the gallbladder.Massive ascites as well as a pleural effusion were also detected.Under the diagnosis of perforation of the digestive tract,we performed emergency surgery.Beyond our expectations,the perforation site was not in the alimentary tract,but rather in the gallbladder.We then diagnosed the patient with emphysematous cholecystitis with perforation,and performed cholecystectomy.A pathological examination of the resected gallbladder revealed necrosis in the mucosa and thinning of the wall.Cultures of the ascites detected Clostridium perfringens,a gas-producing microorganism.  相似文献   
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Bohring–Opitz syndrome (BOS) is a rare disease with a number of characteristic features, including hypertelorism, prominent metopic suture, exophthalmos, cleft palate, abnormal posture, and developmental retardation. Here, we report a BOS patient presenting with lethal persistent pulmonary hypertension of the newborn (PPHN) and inspiratory respiratory failure. The female infant was treated with nitric oxide and vasodilator, which did not improve her condition. The inspiratory respiratory failure required management with deep sedation. She died on postnatal day 60 due to progressed heart failure. Whole exome sequencing revealed de novo mutation in the ASXL1 gene, c.1934dupG, p.Gly646TrpfsTer12.  相似文献   
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