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101.
AIMS: To assess the relationship between neighbourhood deprivation and the rate of gestational diabetes mellitus (GDM) using routinely collected data from a clinical information system, in Plymouth, UK. METHODS: Between 1 January 1996 and 31 December 1997, 3933 women residing within the Plymouth Primary Care Trust (PCT) were screened for GDM using indices of neighbourhood deprivation and prevalence of GDM. Areas (n = 43) were classified according to the Townsend index, measuring material deprivation. Pregnant women with and without GDM were compared. RESULTS: The prevalence of GDM was 1.7%[95%, confidence interval (CI) 1.20, 2.11]. The prevalence of GDM ranged from 1.05% (95% CI 0.60, 1.70) in the most deprived to 2.10% (95%, CI 1.34, 3.13), in the least deprived neighbourhood. Crude rates decreased by 50%[relative prevalence (RP) (95% CI) 0.50 (0.27, 0.94); P = 0.06] amongst those living in the most-deprived compared with those living in the least-deprived areas. Using a stepwise binary logistic regression model, older age at delivery significantly increased the risk of developing GDM. [RP (95%, CI) 1.09, (1.04, 1.13)]. Townsend deprivation score had no significant independent association with GDM when other covariates were considered. CONCLUSION: These data suggest that the neighbourhood context in which women live has no impact on the risk of GDM. Diabet.  相似文献   
102.
In this review, we critically evaluate the evidence for local IgE production in allergic rhinitis mucosa and the concept of local allergy in non-atopic idiopathic rhinitis. Significantly, fewer studies have focused on the disease pathways associated with non-allergic rhinitis compared with their allergic counterparts. Recently, there's been a revival of the hypothesis concerning the existence of local tissue-specific allergic disease confined to the nasal mucosa of some systemically non-atopic rhinitis subjects. Providing the evidence for local mucosal IgE production in allergic rhinitis is a pre-requisite to reviewing its existence in non-allergic rhinitis. In addition, practical and theoretical approaches useful in the detection of allergy in non-allergic rhinitis will be discussed. Furthermore, successful therapeutic regimens used in the treatment of non-allergic rhinitis will be examined as these could provide an insight into the underlying pathophysiology of this common but poorly understood disease.  相似文献   
103.
Abstract   We evaluated the associations between glycemic therapies and prevalence of diabetic peripheral neuropathy (DPN) at baseline among participants in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial on medical and revascularization therapies for coronary artery disease (CAD) and on insulin-sensitizing vs. insulin-providing treatments for diabetes. A total of 2,368 patients with type 2 diabetes and CAD was evaluated. DPN was defined as clinical examination score >2 using the Michigan Neuropathy Screening Instrument (MNSI). DPN odds ratios across different groups of glycemic therapy were evaluated by multiple logistic regression adjusted for multiple covariates including age, sex, hemoglobin A1c (HbA1c), and diabetes duration. Fifty-one percent of BARI 2D subjects with valid baseline characteristics and MNSI scores had DPN. After adjusting for all variables, use of insulin was significantly associated with DPN (OR = 1.57, 95% CI: 1.15–2.13). Patients on sulfonylurea (SU) or combination of SU/metformin (Met)/thiazolidinediones (TZD) had marginally higher rates of DPN than the Met/TZD group. This cross-sectional study in a cohort of patients with type 2 diabetes and CAD showed association of insulin use with higher DPN prevalence, independent of disease duration, glycemic control, and other characteristics. The causality between a glycemic control strategy and DPN cannot be evaluated in this cross-sectional study, but continued assessment of DPN and randomized therapies in BARI 2D trial may provide further explanations on the development of DPN.  相似文献   
104.
105.

Background  

Long-term survival for combined aortic and mitral valve replacement appears to be determined by the mitral valve prosthesis from our previous studies. This 21-year retrospective study assess long-term outcome and durability of aortic valve replacement (AVR) with either concomitant mitral valve replacement (MVR) or mitral valve repair (MVrep). We consider only a single mechanical prosthesis.  相似文献   
106.
107.
Five studies were conducted to examine the degree of variability to be expected during the use of the non-imaging nuclear probe (BIOS Inc.) under a variety of clinical conditions. Comparison of the ejection fraction (EF) readings between the nuclear probe and a gamma camera showed good agreement, with the nuclear probe tending to underestimate lower, and overestimate higher camera EF values [mean (S.D.) difference, 0.84% (6.06)]. A comparison of two nuclear probes showed a small mean (S.D.) difference of EF readings of 0.063% (2.26). EF readings obtained in normal subjects 6 weeks apart were reproducible and differed by a mean (S.D.) of 0.23% (4.42). The administration of placebo to 10 normal subjects followed by sequential measurements for 4 h produced EF changes large enough to mimic a clinical effect, the largest hourly change observed being 5.4%, indicating the need for strict placebo control in interventional experiments. Data on four patients with heart failure showed small non-significant EF changes in the 1 h after placebo administration but a wide intra-subject range of ejection time and time to peak filling measurements. This highlights the problem of accurate, reproducible cursor placement in such patients. The nuclear probe is a portable, low cost instrument which produces accurate EF measurements when compared with the gamma camera.  相似文献   
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109.
Regional cerebral [11C]3-O-methyl-D-glucose ([11C]MeG) uptake kinetics have been measured in five insulin-dependent diabetic patients and four normal controls using positron emission tomography (PET). Concomitant measurement of regional cerebral blood volume and CBF enabled corrections for the presence of intravascular [11C]MeG signal in cerebral regions of interest to be carried out, and regional cerebral [11C]MeG unidirectional extraction fractions to be computed. Four of the five diabetic subjects were studied with their fasting plasma glucose level clamped at a normoglycaemic level (4 mM), and four were studied at hyperglycaemic plasma glucose levels (mean 13 mM). The four diabetic subjects whose fasting plasma glucose levels were clamped at a normoglycaemic level of 4 mM had mean fasting whole-brain, cortical, and white matter [11C]MeG extraction fractions of 15, 15, and 16%, respectively, values similar to those found for the four normal controls (whole brain, 14%; cortex, 13%; white matter, 17%). Mean regional cerebral [11C]MeG extraction fractions were significantly reduced in diabetic subjects during hyperglycaemia whether their plasma insulin levels were undetectable or whether they were raised by continuous intravenous insulin infusion. Such a reduction in [11C]MeG extraction under hyperglycaemic conditions can be explained entirely in terms of increased competition between [11C]MeG and D-glucose for the passive facilitated transport carrier system for hexoses across the blood-brain barrier (BBB). It is concluded that the number and affinity of D-glucose carriers present in the BBB are within normal limits in treated insulin-dependent diabetic subjects. In addition, insulin appears to have no effect on the transport of D-glucose across the BBB.  相似文献   
110.
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