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Mutations in PAX6/Pax6 lead to a variety of ocular anomalies in humans and mice. The aim of the study was to characterise the ocular abnormalities caused by the missense Pax6Leca4 mutation and compare them to published observations on Pax6 alleles that are functionally equivalent to Pax6 null alleles (such as Pax6Sey and Pax6Sey-Neu) and human inherited eye diseases. Ocular features of homozygous Pax6Leca4/Leca4 and heterozygous Pax6Leca4/+ embryos at E12.5-E18.5, heterozygous Pax6Leca4/+ young mice at P18 and heterozygous Pax6Leca4/+ adults at 12 weeks were analysed histologically with their wild-type Pax6+/+ littermates. Homozygous Pax6Leca4/Leca4 fetuses died perinatally with no eyes although an optic cup rudiment with pigmented cells developed. Pax6Leca4/+ mice were microphthalmic and a range of other severe ocular phenotypes affected both the anterior and the posterior segments. In contrast to Pax6+/−, the Pax6Leca4/+ eyes had no goblet cells in the corneal epithelium, the iris was not hypoplastic and there was no lens-corneal epithelial plug. However, microphthalmia was more severe, corneal vascularisation occurred earlier (during fetal stages), pigmented cells were present in the vitreous and corneal stroma and the ciliary body was malformed or abnormal. These results show that, although Pax6Leca4/+ lacked some eye abnormalities commonly seen in Pax6Sey/+ and Pax6Sey-Neu/+ eyes, in most respects their eyes were more severely affected. These differences probably reflect both differences between the Pax6Leca4 and the Pax6Sey-Neu mutations and differences in modifier gene expression in different genetic backgrounds. The presence of pigmented cells in the cornea is a novel observation. Some Pax6Leca4/+ ocular abnormalities were similar to those present in human Peters' anomaly and persistent hyperplastic primary vitreous (PHPV) so Pax6Leca4/+ mice provide a useful model for some inherited eye diseases.  相似文献   
963.
BackgroundSeveral studies have shown that socioeconomic deprivation is associated with increased hospitalization lengths of stay (LOS) and costs. Yet, the French DRG-based information system (PMSI) does not take deprived situations into account. Hence, we aimed at extracting routinely available variables measuring deprivation from the Hospital Information System and at assessing their association with severity of illness and hospital LOS.MethodsWe performed record linkage between the PMSI database concerning stays of patients aged more than 16 years in the short-stay sector of Assistance publique–Hôpitaux de Paris in 2007 and an administrative database which provided the following deprivation measures: recipients of Couverture Médicale Universelle (basic or complementary health insurances adapted for underprivileged French citizens) or Aide Médicale d’État (health and medical emergency insurances adapted for underprivileged non French citizens living in France) and homeless patients. We compared length of stays showing a deprivation measure to others after adjustment on morbidity, age and sex.ResultsAmong 352,721 stays, the prevalence of the deprivation measures ranged from 0.71% for “homelessness” to 6.24% for complementary Couverture Médicale Universelle. Stays showing a deprivation measure had specific illnesses and had more frequently associated comorbidities or complications than others. After adjustment, deprivation measures were associated with significantly increased LOS (by 5% for Couverture Médicale Universelle to 48% for emergency Aide Médicale d’État.ConclusionRoutine extraction of deprivation measures from Hospital Information Systems is feasible. Age, sex and illness being equal, these deprivation measures were associated with more complicated cases and increased LOS. We recommend that case mix-based hospital prospective payment systems take socioeconomic deprivation into account.  相似文献   
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Heat shock proteins are diverse and essential components of cell physiology. Their expression is elevated in the cell undergoing stress, where they protect the cell from death by necrosis or apoptosis and accelerate recovery. Significant advances have been made in studies relevant to plastic surgery regarding these proteins and their manipulation. This review introduces the heat shock proteins and appraises these studies in skin, ultraviolet light exposure, neoplasia, wound healing, ageing, burns, and reconstructive surgery.  相似文献   
968.
OBJECTIVES: Angioplasty is often used in the management of lower limb ischaemia and can reduce the need for infrainguinal bypass in some patients. There is an associated failure rate with this technique and bypass surgery is often used in this situation as a secondary limb salvage procedure. We aimed to evaluate the outcome of infrainguinal bypass grafting following failed attempt at angioplasty. METHODS: All cases of infrainguinal bypass at a single centre over a seven year period were identified and notes reviewed. Cases were divided into four groups according to their indication for surgery; acute ischaemia, chronic critical ischaemia, failed angioplasty and an 'other' group including aneurysmal disease and claudicants. The failed angioplasty group was compared with the other three groups. Survival analysis was performed using Kaplan Meier curves and groups compared in terms of long term patency and survival. RESULTS: Primary patency was 61.2% in the failed angioplasty group at 12 months compared with 60.6% in the other groups (P=1.11). There was also no significant difference in primary patency at 60 months (50% vs 40.6%, P=0.26). Survival at 12 months was also comparable between the groups (failed angioplasty group 74.2% compared with 77.3% in the other groups, P=0.662) as was 60 months survival (33.3% and 35.4% respectively, P=0.166). DISCUSSION: In this study, outcome of infrainguinal bypass following failed angioplasty was comparable to outcome of surgery performed for another indication. This paper supports the use of distal bypass surgery for limb salvage in cases where minimal access techniques have failed.  相似文献   
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