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OBJECTIVE: To study the etiology, outcome and prognostic indicators in children with fulminant hepatic failure in the United Kingdom. DESIGN: Retrospective review of all patients <17 years with fulminant hepatic failure from 1991 to 2000. Fulminant hepatic failure was defined as presence of coagulopathy (prothrombin time >24 seconds or International Normalized Ratio >2.0) with or without hepatic encephalopathy within 8 weeks of the onset of symptoms. SETTING: Liver Unit, Birmingham Children's Hospital, United Kingdom. RESULTS: Ninety-seven children (48 male, 49 female; median age, 27 months; range, 1 day-192.0 months) were identified with fulminant hepatic failure. The etiologies were: 22 metabolic, 53 infectious, 19 drug-induced, and 3 autoimmune hepatitis. The overall survival rate was 61%. 33% (32/97) recovered spontaneously with supportive management. Fifty-five children were assessed for liver transplantation. Four were unstable and were not listed for liver transplantation; 11 died while awaiting liver transplantation. Liver transplantation was contraindicated in 10 children. Of the 40 children who underwent liver transplantation, 27 survived. Children with autoimmune hepatitis, paracetamol overdose or hepatitis A were more likely to survive without liver transplantation. Children who had a delay between the first symptom of liver disease and the onset of hepatic encephalopathy (median, 10.5 days versus 3.5 days), higher plasma bilirubin (299 micromol/L versus 80 micromol/L), higher prothrombin time (62 seconds versus 40 seconds) or lower alanine aminotransferase (1288 IU/L versus 2929 IU/L) levels on admission were more likely to die of fulminant hepatic failure or require liver transplantation (P < 0.05). On multivariate analysis, the significant independent predictors for the eventual failure of conservative therapy were time to onset of hepatic encephalopathy >7 days, prothrombin time >55 seconds and alanine aminotransferase 相似文献   
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PURPOSE: To examine the relationship between intraocular pressure (IOP), anthropomorphic, demographic, socioeconomic, systemic, and ocular factors and glaucomatous optic neuropathy (GON) in Chinese people. METHODS: Chinese people (n = 2000), aged 40 to 79 years, were selected from the Singapore electoral register. Of the 1717 considered eligible for examination, 1232 participated, representing a response rate of 71.8%. IOP was estimated with Goldmann applanation tonometry. The drainage angle was assessed with static and dynamic gonioscopy. The optic nerve was examined at high magnification through a dilated pupil with a fundus contact lens or a +78-D lens. Static automated visual field testing was performed on subjects with suspected glaucoma. GON was diagnosed on the basis of structural and functional abnormalities of the optic nerve. RESULTS: The main independent determinants of higher IOP were higher systolic blood pressure (P < 0.001), quadrants of any peripheral anterior synechiae (PAS, P = 0.02) and width of the drainage angle (P = 0.049). A 100- micro m increase in corneal thickness was associated with an increase in mean IOP of 1.5 to 1.8 mm Hg (P < 0.001). Odds of GON increased 1.2 times per 1-mm Hg increase in screening IOP. A clear association between corneal thickness and GON was not identified. CONCLUSIONS: Clinical IOP estimates are related to systolic blood pressure and corneal thickness. Variation in IOP with angle width may suggest that trabecular compaction significantly contributes to causes of the increase in IOP, independent of angle-closure. GON is an IOP-related phenomenon among Chinese Singaporeans.  相似文献   
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PURPOSE: To determine the prevalence and risk factors for pterygium in the Chinese population of Singapore. METHODS: A population-based survey was conducted in Singapore, an island located 1 degree north of the equator with a stable tropical climate. A disproportionate, stratified, clustered, random sampling procedure was used to select the names of 2000 Chinese people aged 40 to 79 years from the 1996 electoral register in the Tanjong Pagar district of Singapore. Selected subjects underwent a comprehensive interview and ocular examination. Pterygium was diagnosed and graded clinically as grade 1 (transparent), 2 (intermediate), and 3 (opaque). Risks factors associated with pterygium and grade 3 pterygium were evaluated with logistic regression models. RESULTS: From a total of 1717 eligible subjects, 1232 (71.8%) were examined. There were 120 people with either unilateral (n = 70) or bilateral (n = 50) pterygium, equivalent to an overall prevalence of 6.9% (95% confidence interval [CI], 5.2, 8.8) in the Chinese population aged 40 and older. The prevalence increased linearly with age (chi-square test of trend P <.001) and was higher among men than women (age-adjusted odds ratio [OR], 4.2; 95% CI, 2.5, 6.9). Men aged 70 and above had the highest overall prevalence of 25.4% (95% CI, 18.2, 19.4), but pterygium was not seen in women aged 40 to -49 years. In multivariate analysis, ptergyium was independently associated with increasing age (OR, 7.8; 95% CI, 3.2, 18.8 for persons 70 to 81 years, compared with 40 to 49 years), male sex (OR, 5.1; 95% CI, 2.9, 9.3) and certain occupations; factory workers, production workers and machine operators (OR, 3.1; 95% CI, 1.5, 6.3), as well as laborers and agricultural workers (OR, 3.3; 95% CI, 1.6, 7.0) had higher risks, compared with professionals and office workers. Grade 3 pterygium (n = 36) was also independently associated with male sex (OR, 11.6; 95% CI, 3.5, 38.6) and similar occupations but was not related to age. CONCLUSIONS: The prevalence of pterygium in Singapore is 7% among Chinese aged 40 years and older. Independent associations with increasing age, male sex, and occupations linked to outdoor work and other exposures suggest a multifactorial cause of this condition.  相似文献   
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Purpose: To investigate the results of combined phacoemulsification, intraocular lens implantation and trabeculectomy in Asian patients with chronic angle closure glaucoma (CACG). Methods: This was a retrospective non-comparative case series of 55 consecutive patients (57 eyes) who underwent phacoemulsification, posterior chamber intraocular lens implantation and trabeculectomy for CACG at the Singapore National Eye Centre between 1997–1998. The surgical outcome was assessed in terms of intraocular pressure (IOP), the incidence of complications and the visual acuity at last follow-up. Success was defined as final IOP 21 mmHg without medication and qualified success as final IOP 21 mmHg with medication. Patients with final IOP > 21 mmHg who required further glaucoma surgery, lost light perception or became pthisical, were classified as failures. The eyes were further categorized into two groups according to whether single-site or separate-sitesurgery was performed. The outcome was also compared among eyes in which per-operative antimetabolites were applied to the trabeculectomy site and those without antimetabolites. Results: The mean follow up was 22.0 ± 5.6 months (mean ± SD). Success was achieved in 46 (81%) eyes, qualified success in 10 (17%) eyes, and failure in 1 (2%) eye. In terms of IOP outcome, the success rate was similar in the two surgical groups (single-site or separate-site).There was no significant difference in IOP outcome among eyes in which per-operative antimetabolites were used and eyes with no per-operativeantimetabolites use. Forty-one eyes (72%) had 6/12 or better vision. There were no cases of intraoperative complications and the incidence of postoperative complications was low. Conclusions: Combined phacoemulsification, intraocular lens implantation and trabeculectomy is associated with good intraocular pressure control and visual outcome in patients with CACG.  相似文献   
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Gustavsson N  Wang Y  Kang Y  Seah T  Chua S  Radda GK  Han W 《Diabetologia》2011,54(7):1824-1830

Aims/hypothesis  

Glucagon-like peptide-1 (GLP-1), a hormone with potent antihyperglycaemic effects, is produced and secreted from highly specialised gut endocrine L-cells. It regulates glucose homeostasis by promoting glucose-dependent insulin secretion, suppressing glucagon secretion and enhancing insulin sensitivity. Similar to islet alpha and beta cells, L-cells are electrically excitable, and express calcium channels and ATP-sensitive potassium channels. GLP-1 is also stored in secretory granules, the exocytosis of which is triggered by increased intracellular calcium levels. Although the calcium dependence of GLP-1 granule exocytosis is well established, the identities of calcium-sensing proteins in GLP-1 secretion remain elusive. Here we tested whether synaptotagmin-7, a calcium sensor in pancreatic alpha and beta cells, regulates GLP-1 secretion.  相似文献   
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