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Alternative splicing has been shown to occur at the metabotropic glutamate receptor 1 (mGluR1) gene. Three main isoforms that differ in their carboxy-termini have been described so far and named mGluR1alpha, mGluR1beta and mGluR1c. These variants when expressed in recombinant systems all activate phospholipase C, although the [Ca2+] signals generated have different kinetics. Tissue distribution studies of specific mGluR1 splice variants are limited to the mGluR1alpha isoform. In the present work, we examined the localization of mGluR1beta in the adult rat and mouse forebrain by using a specific antipeptide antibody. Furthermore, the mGluR1beta immunostaining was compared with that obtained with antibodies specific for mGluR1alpha or with a pan-mGluR1 antibody which recognizes all isoforms. mGluR1beta-like immunoreactivity (LI) was found confined to the neuropil and neuronal perikarya and appeared discretely distributed in the rodent forebrain. Differential cellular distribution between mGluR1alpha and mGluR1beta was observed. In the hippocampus, mGluR1alpha-LI was restricted to non-principal neurons in all fields, whereas mGluR1beta-LI was strongest in principal cells of the CA3 field and dentate granule cells but absent in CA1. We have also shown that the vast majority of neurons in the striatum express mGluR1. The predominant form appeared to be mGluR1beta, with a distribution pattern reflecting the patch-matrix organization of the striatum. The specificity of the immunoreactivity described for mGluR1 splice variants was confirmed in mGluR1-deficient mice. The observation of a different cellular and regional distribution of mGluR1 splice variants, in particular in the hippocampus, suggests that they may mediate different roles in synaptic transmission.  相似文献   
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The features of the rare interstitial hernia, as seen in four children, are described. All were boys ranging in age from 7 days to 7 years. The presenting sign was swelling in the right side of the abdomen associated with undescended testis. The hernias arose at the deep inguinal ring and expanded superiorly between the internal and external oblique muscles. Repair involved a standard herniotomy and orchidopexy through an oblique inguinal incision-except in one patient with a vanishing testis. The importance of being aware of this rare type of hernia is stressed.  相似文献   
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Withdrawal from dialysis has been a significant cause of mortality among dialysis patients, accounting for 6 to 22% of deaths. Since 1990, a new death notification form has allowed more detailed analyses of withdrawal from dialysis separate from causes of death. Using the U.S. Renal Data System data base, this study examined 116,829 deaths in adult patients from 1990 to 1995. Adjusted odds ratios were calculated for the risk of withdrawal using logistic regression. Adjustments included age at death, ethnicity, gender, cause of death, primary cause of end-stage renal disease, time on dialysis, and dialysis modality. In addition, odds ratios of withdrawal were calculated for deaths in patients who started dialysis after age 65. Death was preceded by withdrawal significantly more frequently in women than in men, more than twice as frequently in Caucasians than in African-Americans or Asians, and more frequently in older than in younger age groups. Patients who died of chronic diseases (e.g., dementia, malignancy) were much more likely to withdraw before death, whereas patients who died from more acute causes (e.g., coronary artery disease) were less likely to withdraw before death. It is concluded that patients who are Caucasian, female, older, or die of chronic or progressive diseases are more likely to withdraw from dialysis before death. The ethnic and gender differences in withdrawal do not appear to have a medical explanation from this analysis. Further research along sociologic lines is needed to better explain the differences in withdrawal from chronic dialysis.  相似文献   
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Renal transplantation is the most successful treatment strategy for patients with ESRD to improve survival and quality of life. The study presented here examines the relationship of gender and living related (LR) transplantation donor and recipient rates in the United States. National data from the United States Renal Data System (USRDS) were used for this study. All LR transplants occurring between 1991 and 1993 among blacks and whites were included (N = 6193). Transplantation and donation rates for men and women were calculated. Poisson regression was used to calculate female/male transplantation and donation rate ratios. Overall, women were 10% less likely to receive a LR transplant than men (rate ratio [RR] = 0.90, P < 0.001). This gender difference increased over time from 1991 (Female/Male RR = 0.95, P = not significant [NS]) to 1993 (RR = 0.85, P < 0.001). In contrast, women were significantly more likely to donate a kidney than men (RR = 1.28, P < 0.001 and RR = 1.29, P < 0.001 among whites and blacks, respectively). Analyses by age subgroups revealed that only among ESRD patients aged 20 to 44 yr was the likelihood of receiving a LR kidney transplant equal for men and women. Higher donation rates among women compared with men were observed in all donor age and race subgroups except young blacks (aged 0 to 19 yr). Recipient gender appeared to influence donation rates. The female-to-male relative donation rates were higher when donations were to female, compared with male, recipients. This study of national data suggests an imbalance in LR donation and transplantation between men and women. Women are more likely to donate a kidney but are less likely to receive a LR transplant than men. Several potential explanatory factors are explored. These findings suggest a need for the development of gender-appropriate interventions to encourage donation among men and LR transplantation among women, to ultimately facilitate greater use of this ESRD treatment modality.  相似文献   
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OBJECTIVE: To investigate the association of GAD (65-kDa) autoantibodies (GAD65-Abs) and IA-2 autoantibodies (IA-2-Abs) with human leukocyte antigen (HLA)-DQ and insulin gene (INS) risk markers in patients with recent-onset IDDM and their siblings. RESEARCH DESIGN AND METHODS: Blood was sampled from 608 recent-onset IDDM patients and 480 siblings, aged 0-39 years and consecutively recruited by the Belgian Diabetes Registry, to determine GAD65- and IA-2-Ab (radiobinding assay), HLA-DQ- (allele-specific oligonucleotyping), and INS-genotypes (restriction fragment length polymorphism analysis; siblings, n = 439). RESULTS: At the onset of IDDM, GAD65-Abs were preferentially associated with two populations at genetic risk but only in the 20- to 39-year age-group: 1) their prevalence was higher in carriers of DQA1*0301-DQB1*0302 (88 vs. 73% in non[DQA1*0301-DQB1*0302], P = 0.001), and 2) an association was found in patients lacking this haplotype but carrying DQA1*0501-DQB1*0201, together with INS I/I (87 vs. 54% vs. non[INS I/I], P = 0.003). Siblings of IDDM patients also presented the association of GAD65-Abs with DQA1*0301-DQB1*0302 (13 vs. 2% non[DQA1*0301-DQB1*0302], P < 0.001), while associations with the second genetic risk group could not yet be assessed. At the onset of IDDM, IA-2-Ab prevalence was higher in carriers of DQA1*0301-DQB1*0302 (69 vs. 39% non[DQA1*0301-DQB1*0302], P < 0.001) but not of DQA1*0501-DQB1*0201 or INS I/I. This association was present in both the 0- to 19- and the 20- to 39-year age-groups. It was also found in siblings of IDDM patients (4 vs. 0% non[DQA1*0301-DQB1*0302], P < 0.001). CONCLUSIONS: Both GAD65- and IA-2-Abs exhibit higher prevalences in presence of HLA-DQ- and/or INS-genetic risk markers. Their respective associations differ with age at clinical onset, suggesting a possible usefulness in the identification of subgroups in this heterogeneous disease.  相似文献   
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PURPOSE: The aim of this study was to evaluate the influence of optic disc size on the ability of variables generated by the Heidelberg Retina Tomograph, software version 1.11, to distinguish glaucoma patients from normals in a cross-sectional study. PATIENTS AND METHODS: For evaluation of the optic disc with the Heidelberg Retina Tomograph, eyes of 87 normals and 61 glaucoma patients were selected. Disc area, volume above reference, rim area, cup area, cup volume, third moment in contour and the mean retinal nerve fibre layer thickness at the border of the optic disc were selected for evaluation. The sensitivity at 80% specificity of these variables was calculated under three conditions: (1) no correction for disc size; (2) calculation in the following disc size ranges: class I (1.0-2.0 mm2), class II (2.0-2.5 mm2), class III (2.5-3.15 mm2) and class IV (3.15-5.0 mm2); (3) calculation globally, taking into account the different disc sizes of the four classes. RESULTS: Neuroretinal rim area, cup area and volume, third moment and nerve fibre layer thickness were significantly and positively correlated with optic disc size in normals. Neuroretinal rim volume measurements were statistically independent of optic disc size. Sensitivity was lowest when the size of the optic disc was not considered. Sensitivity increased when evaluated in four optic disc size classes. With growing optic disc size sensitivity of the retinal nerve fibre layer increased and third moment value decreased. Cup volume and area had their lowest sensitivity for large optic discs. The area of the neuroretinal rim was the only variable which showed similar sensitivity values under all three conditions. CONCLUSIONS: The sensitivities of HRT variables varied with optic disc size. Evaluation of their sensitivity requires the definition of optic disc classes or statistical correction for the size of the optic disc.  相似文献   
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