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ResearchGate is a world wide web for scientists and researchers to share papers, ask and answer questions, and find collaborators. As one of the more than 15 million members, the author uploads research output and reads and responds to some of the questions raised, which are related to type 2 diabetes. In that way, he noticed a serious gap of knowledge of this disease among medical professionals over recent decades. The main aim of the current study is to remedy this situation through providing a comprehensive review on recent developments in biochemistry and molecular biology, which can be helpful for the scientific understanding of the molecular nature of type 2 diabetes. To fill up the shortcomings in the curricula of medical education, and to familiarize the medical community with a new concept of the onset of type 2 diabetes, items are discussed like: Insulin resistance, glucose effectiveness, insulin sensitivity, cell membranes, membrane flexibility, unsaturation index (UI; number of carbon-carbon double bonds per 100 acyl chains of membrane phospholipids), slow-down principle, effects of temperature acclimation on phospholipid membrane composition, free fatty acids, energy transport, onset of type 2 diabetes, metformin, and exercise. Based on the reviewed data, a new model is presented with proposed steps in the development of type 2 diabetes, a disease arising as a result of a hypothetical hereditary anomaly, which causes hyperthermia in and around the mitochondria. Hyperthermia is counterbalanced by the slow-down principle, which lowers the amount of carbon-carbon double bonds of membrane phospholipid acyl chains. The accompanying reduction in the UI lowers membrane flexibility, promotes a redistribution of the lateral pressure in cell membranes, and thereby reduces the glucose transporter protein pore diameter of the transmembrane glucose transport channel of all Class I GLUT proteins. These events will set up a reduction in transmembrane glucose transport. So, a new blood glucose regulation system, effective in type 2 diabetes and its prediabetic phase, is based on variations in the acyl composition of phospholipids and operates independent of changes in insulin and glucose concentration. UI assessment is currently arising as a promising analytical technology for a membrane flexibility analysis. An increase in mitochondrial heat production plays a pivotal role in the existence of this regulation system.  相似文献   
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To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty.  相似文献   
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The bioavailability in rabbit cornea and aqueous humor of an ophthalmic formulation of suprofen, a nonsteroidal anti-inflammatory drug, was evaluated following topical administration of a single dose to the eye. The drug penetrated rapidly into the uninflamed cornea with intact epithelium; highest levels occurred during the first 30 to 45 min after instillation and decreased thereafter. The bioavailability of suprofen in cornea and aqueous humor following administration of a 1.0% concentration was twice that produced by a 0.5% concentration of the drug. Topical application of multiple doses of suprofen failed to suppress polymorphonuclear leukocyte invasion of the cornea if treatment was started after the induction of inflammation. Suprofen therapy initiated prior to the induction of corneal inflammation and maintained into the post-inflammation period did produce a significant (P less than 0.01) decrease in the numbers of PMNs that invaded the inflamed cornea. There was no significant difference (P greater than 0.05) in the corneal anti-inflammatory effect achieved by the 0.5% and 1.0% concentrations of suprofen when administered according to this regimen.  相似文献   
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A retrospective review of post-delivery antibody records was performed at a teaching hospital and a community hospital to determine the frequency of new red cell alloantibody production and transfusion during pregnancy. If alloantibody was undetected at delivery, it was assumed that alloimmunization had not occurred. When antibody was detected, a chart review was performed to determine if the antibody was present at the beginning of the pregnancy or was newly produced during the pregnancy. A total of 17,568 pregnancies were reviewed. Antibody was detected at delivery in 948 (5.4%) cases, of which 89.5 percent (848/948) involved passive anti-D or clinically insignificant antibodies. The remaining 100 pregnancies involved clinically significant IgG antibodies. In 58 pregnancies, the antibody was detected in the first trimester, and in 42, new antibody production occurred during the pregnancy. Thus, the prevalence of new antibody production during pregnancy was 0.24 percent (95% confidence interval [CI], 0.17-0.32). Transfusion records indicated that the prevalence of transfusions during pregnancy was 0.09 percent (95% CI, 0.04-0.14). None of the women with new alloantibody formation during their pregnancies required transfusion; hence, new alloantibody production and the need for transfusion appear to be independent events. The probability of these events occurring together was 2.1 × 10(-6), or 1 in 500,000 deliveries.  相似文献   
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Adult soft tissue sarcomas are a heterogeneous group of tumors, including well-described subtypes by histological and genotypic criteria, and pleomorphic tumors typically characterized by non-recurrent genetic aberrations and karyotypic heterogeneity. The latter pose a diagnostic challenge, even to experienced pathologists. We proposed that gene expression profiling in soft tissue sarcoma would identify a genomic-based classification scheme that is useful in diagnosis. RNA samples from 51 pathologically confirmed cases, representing nine different histological subtypes of adult soft tissue sarcoma, were examined using the Affymetrix U95A GeneChip. Statistical tests were performed on experimental groups identified by cluster analysis, to find discriminating genes that could subsequently be applied in a support vector machine algorithm. Synovial sarcomas, round-cell/myxoid liposarcomas, clear-cell sarcomas and gastrointestinal stromal tumors displayed remarkably distinct and homogenous gene expression profiles. Pleomorphic tumors were heterogeneous. Notably, a subset of malignant fibrous histiocytomas, a controversialhistological subtype, was identified as a distinct genomic group. The support vector machine algorithm supported a genomic basis for diagnosis, with both high sensitivity and specificity. In conclusion, we showed gene expression profiling to be useful in classification and diagnosis, providing insights into pathogenesis and pointing to potential new therapeutic targets of soft tissue sarcoma.  相似文献   
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Neuroprotective effects of eliprodil in retinal excitotoxicity and ischemia   总被引:9,自引:0,他引:9  
PURPOSE: To evaluate whether eliprodil (SL82.0715), a NR2B-selective N-methyl-D-aspartate (NMDA) antagonist, is protective of retina subjected to an excitotoxic or ischemic insult. METHODS: To evaluate protection against retinal excitotoxicity, eliprodil was administered intraperitoneally before and after the injection of NMDA (5 microl, 20 nmol) into the vitreous of rats. Integrity of the retina was assessed by counting cells in the retinal ganglion cell layer (GCL) and measuring choline acetyltransferase (ChAT) activity. In a subsequent experiment, total retinal ischemia, as measured by a cessation of electroretinographic (ERG) activity, was induced in anesthetized rabbits by elevating intraocular pressure above systolic blood pressure for 65 minutes. After ischemia, recovery of ERG activity was assessed at 24 and 48 hours in animals treated with vehicle or eliprodil (1.0-10.0 mg/kg). RESULTS: Intravitreal NMDA injection resulted in a dose-related decrease in cells of the GCL and in ChAT activity. Eliprodil administered intraperitoneally at 10 mg/kg completely prevented the loss of ChAT and the loss of cells in the GCL. Twenty-four hours after retinal ischemia, A and B waves of vehicle-treated animals were suppressed by 60% to 70%. Eliprodil administered intraperitoneally at 10 mg/kg ameliorated the A- and B-wave depression throughout the 48-hour experiment. CONCLUSIONS: Eliprodil is neuroprotective of retinae subjected to either an excitotoxic or ischemic challenge and may be useful for treating a variety of retinal and optic nerve head disorders.  相似文献   
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PURPOSE: To develop a genome-based classification scheme for clear-cell sarcoma (CCS), also known as melanoma of soft parts (MSP), which would have implications for diagnosis and treatment. This tumor displays characteristic features of soft tissue sarcoma (STS), including deep soft tissue primary location and a characteristic translocation, t(12;22)(q13;q12), involving EWS and ATF1 genes. CCS/MSP also has typical melanoma features, including immunoreactivity for S100 and HMB45, pigmentation, MITF-M expression, and a propensity for regional lymph node metastases. MATERIALS AND METHODS: RNA samples from 21 cell lines and 60 pathologically confirmed cases of STS, melanoma, and CCS/MSP were examined using the U95A GeneChip (Affymetrix, Santa Clara, CA). Hierarchical cluster analysis, principal component analysis, and support vector machine (SVM) analysis exploited genomic correlations within the data to classify CCS/MSP. RESULTS: Unsupervised analyses demonstrated a clear distinction between STS and melanoma and, furthermore, showed that CCS/MSP cluster with the melanomas as a distinct group. A supervised SVM learning approach further validated this finding and provided a user-independent approach to diagnosis. Genes of interest that discriminate CCS/MSP included those encoding melanocyte differentiation antigens, MITF, SOX10, ERBB3, and FGFR1. CONCLUSION: Gene expression profiles support the classification of CCS/MSP as a distinct genomic subtype of melanoma. Analysis of these gene profiles using the SVM may be an important diagnostic tool. Genomic analysis identified potential targets for the development of therapeutic strategies in the treatment of this disease.  相似文献   
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