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51.
Lower birth weight is associated with an increased occurrence of type 2 diabetes in later life. Whether this relationship is explained by environmental or genetic factors is unknown. We have examined the potential for genetic influences by determining whether parental diabetes is associated with lower birth weight in 1,608 children of known birth weight and gestational age born between 1941 and 1993 in the Gila River Indian Community in Arizona. The previously described relationships of maternal diabetes to increased birth weight and offspring diabetes were observed. In contrast to this we have determined novel relationships between low birth weight and paternal diabetes. The offspring of diabetic fathers were, on average, 78 g lighter than the offspring of nondiabetic fathers. For fathers, lower birth weight in their offspring was associated with an increased risk of later diabetes, i.e., fathers of offspring in the lowest quintile of birth weight, who were not diabetic at the time of birth of their child, had a 1.8-fold increased risk of developing diabetes later in life (95% CI 1.2-2.7; P = 0.004). For children, lower birth weight predicted diabetes in the offspring if paternal but not maternal diabetes was present, but it was not associated with higher plasma glucose if neither parent had diabetes. We conclude that the risk of diabetes associated with low birth weight is strongly related to the development of paternal diabetes, suggesting a genetic link between lower birth weight and later diabetes.  相似文献   
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PurposeThe aim of this study was to assess both retinal and cortical structure in a cohort of patients with long-term acquired central retinal disease in order to identify potential disease biomarkers and to explore the relationship between the anterior and posterior visual pathways.MethodsFourteen participants diagnosed with long-term central retinal disease underwent structural assessments of the retina using spectral-domain optical coherence tomography, including macular ganglion cell layer (GCL) and peripapillary retinal nerve fiber layer (pRNFL) thickness. Structural magnetic resonance imaging was used to measure visual cortex, including cortical volume of the entire occipital lobe and cortical thickness of the occipital pole and calcarine sulcus, representing the central and peripheral retina, respectively.ResultsMean thickness was significantly reduced in both the macular GCL and the inferior temporal pRNFL across patients. Cortical thickness was significantly reduced in both the occipital pole and calcarine sulcus, representing the central and peripheral retina, respectively. Disease duration significantly correlated with GCL thickness with a large effect size, whereas a medium effect size suggests the possibility that cortical thickness in the occipital pole may correlate with visual acuity.ConclusionsLong-term central retinal disease is associated with significant structural changes to both the retina and the brain. Exploratory analysis suggests that monitoring GCL thickness may be a sensitive biomarker of disease progression and reductions in visual cortical thickness may be associated with reduced visual acuity. Although this study is limited by its heterogeneous population, larger cohort studies would be needed to better establish some of the relationships detected between disease dependent structural properties of the anterior and posterior visual pathway given the effect sizes reported in our exploratory analysis.  相似文献   
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Two non-covalently linked copies of the retrovirus genome are specifically recruited to the site of virus particle assembly and packaged into released particles. Retroviral RNA packaging requires RNA export of the unspliced genomic RNA from the nucleus, translocation of the genome to virus assembly sites, and specific interaction with Gag, the main viral structural protein. While some aspects of the RNA packaging process are understood, many others remain poorly understood. In this review, we provide an update on recent advancements in understanding the mechanism of RNA packaging for retroviruses that cause disease in humans, i.e., HIV-1, HIV-2, and HTLV-1, as well as advances in the understanding of the details of genomic RNA nuclear export, genome translocation to virus assembly sites, and genomic RNA dimerization.  相似文献   
54.
Interventricular septal thickness in fetuses of diabetic mothers.   总被引:8,自引:0,他引:8  
Sixty-four diabetic women had their fetuses studied by M-mode echocardiogram between 20-41 weeks of gestation. The mean septal size during both diastole and systole increased in a linear fashion with advancing gestational age in both the normal and diabetic groups. Ventricular septal hypertrophy (ie, more than 2 standard deviations above the normal mean) was present in 48 of 64 (75%) of the fetuses of diabetic women. The ratio of septal size to the anteroposterior cardiac dimension was significantly greater in the diabetic than in the normal group (12 versus 8%; P less than .05). The anteroposterior cardiac dimension indexed to the estimated fetal weight was also greater in the diabetic group. Because both septum and cardiac dimension are larger with maternal diabetes, there may be a specific diabetic cardiomyopathy that originates in utero.  相似文献   
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Further delineation of Weaver syndrome   总被引:6,自引:0,他引:6  
Seven new cases of Weaver syndrome are described, including the first reported case in an adult. Overgrowth is usually but not always present. The combination of characteristic facies and developmental delay, with the peculiar radiographic findings of accelerated dysharmonic osseous maturation and splaying of the distal long bones, is diagnostic of Weaver syndrome.  相似文献   
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Many azoospermic men do not possess mature spermatozoa at the time of surgical sperm extraction.This study is a systematic review and meta-analysis evaluating o...  相似文献   
60.
Benoxaprofen (BPF) induces a clinical photosensitivity which resembles idiopathic solar urticaria. This response is mediated by degranulation of mast cells. Since mast-cell degranulation is known to be modulated by phospholipid alteration, we examined the effect of BPF and ultraviolet radiation (UV) on phospholipid metabolism of C3H 10 T1/2 cells in culture. BPF + UVB (280-320 nm) induced release of [3H]arachidonic acid (AA) but did not alter the release of [3H]choline from prelabelled cells. This suggests that BPF photosensitizes phospholipase A2 activation. Such activation probably represents an integral step in the mechanism of BPF photosensitization of mast-cell degranulation.  相似文献   
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