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The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients.  相似文献   
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In a study of 972 women, sexual characteristics of 66 women with a cervical human papillomavirus infection (CHPI) were compared to the remaining study population. Among a number of sexual variables that were significantly correlated with CHPI were number of lifetime sexual partners, short partnerships, many recent partners, infidelity, casual travel sex, sexual début abroad, oral and anal sex, and sexual abuse. In multifactorial analyses four variables remained significantly correlated with CHPI, i.e., number of lifetime sexual partners, casual travel sex, sexual début abroad, and infidelity. It is concluded that CHPI shows most of the epidemiological characteristics of a sexually transmitted disease.  相似文献   
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Sixty women with breast cancer (mean age: 61 years; range 36-78 years) were treated with Epirubicin (4’epi-Dox-orubicin), 60 mg m-2 , as single drug therapy. The drug was administered as 2 hours’ constant rate infusions. The pharmacokinetics of the drug during the first course of treatment was evaluated by measurements of the plasma concentration of Epirubicin at the end of the infusion period. There was a five-fold inter-individual variation of the dose-normalized maximum plasma concentration, which increased with increasing age of the patients. There was no correlation between this pharmacokinetic parameter and degree of obesity.  相似文献   
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The effect of splanchnic nerve activation on intestinal fluid transport and intramural blood flow distribution was examined in the cat. Previous reports from our laboratory have demonstrated that splanchnic nerve activation increases fluid absorption. The present study was performed to elucidate the mechanisms behind this effect. The results showed an increase in net sodium and chloride transport on splanchnic nerve activation whether intestinal blood flow decreased or not. The effect on sodium transport was due to a decrease in lumen to tissue flux. The effect could not be explained by a decrease in local blood flow, as it was present despite constant blood flow in both the villous and crypt regions. No change was seen in the villous osmolality gradient on splanchnic nerve activation. On the basis of these findings, it is proposed that the in vivo effect of splanchnic nerve activation is due to a decrease in fluid and electrolyte secretion, probably occurring in the intestinal crypts.  相似文献   
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The gene of the p85alpha regulatory subunit of phosphatidylinositol (PI) 3-kinase gives rise to several splice variants. We hypothesized that the expression of p85alpha splice variants may be altered in skeletal muscle from subjects with type 2 diabetes mellitus. Skeletal muscle biopsies were obtained from nine type 2 diabetic and eight healthy men, matched for age, body mass index (BMI) and physical fitness. PI 3-kinase activity in skeletal muscle following in vitro insulin stimulation was reduced in subjects with type 2 diabetes. p85alpha mRNA was elevated fourfold in type 2 diabetic as compared to healthy control subjects ( P<0.05). p85alpha mRNA abundance was positively correlated with plasma insulin concentration ( P<0.01) and serum glucose concentration ( P<0.01). Despite this, protein levels of p85alpha, p55alpha, and the novel human p50alpha were not altered in type 2 diabetic subjects. Thus, although gene expression of full-length p85alpha is increased in skeletal muscle from type 2 diabetics, this is not reflected by increased protein levels. Therefore, defects in PI 3-kinase activity are likely due to impaired activation of the enzyme rather than changes in protein expression of the isoforms of the regulatory subunit.  相似文献   
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We have previously found that interleukin-4 and CD40 monoclonal antibodies (mAb) are strong potentiatiors of homotypic B cell aggregation which is dependent on LFA-1. We show here that CD23 mAb were also able to inhibit aggregation to a similar extent as LFA-1 antibodies. This inhibition was restricted to the MHM6 epitope of CD23 and antibodies to other epitopes [Epstein-Barr virus (EBV) CS-1, EBV CS-2, EBV CS-5 and mAb 25] or occupation of the Fc-binding site by IgE had no or a slightly enhancing effect on aggregation. When testing two antibodies to CD21, the recently defined ligand for CD23, one of these (BU32) was found to be inhibitory whereas the other (THB5) had no effect. By combining antibodies to LFA-1 and CD23, aggregation was often completely inhibited. These data suggest that LFA-1/ICAM-1 and CD23/CD21 are the major molecules involved in homotypic aggregation of human B cells.  相似文献   
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The perforin (PFN) protein is essential for the elimination of target cells by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. The study of cells releasing PFN has been hampered by a lack of sensitive methods. We therefore produced PFN-reactive monoclonal antibodies (mAb) and developed capture enzyme-linked immunosorbent (ELISA) and enzyme-linked immunospot (ELISpot) assays. Three mAbs were generated and shown to react with unique determinants of PFN. All mAbs recognized intracellular PFN in human peripheral blood mononuclear cell (PBMC) as assessed by flow cytometry and immunohistochemistry. Functional PFN capture ELISA and ELISpot assays were developed utilizing two of the mAbs for capture and the third mAb for detection. When examining PFN release by the YT lymphoma cell line, the ELISpot displayed a greater detection sensitivity than the ELISA. Assessment of PFN release by a CTL clone using ELISpot gave results consistent with a parallel (51)Cr-release cytotoxicity assay. Moreover, PFN release by PBMC could be quantified by ELISpot and ELISA after ex vivo stimulation with defined CTL epitopes from common viruses. These novel immunoassays will be valuable for further investigations of the mechanisms underlying granule-mediated apoptosis. In addition, the capture immunoassays could provide tools for studying CTL responses in infectious and tumor diseases as well as for vaccine development.  相似文献   
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