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Renal function has been evaluated in 45 diabetic children (age 12.5±4 years) with a mean diabetes duration of 4.9±3.5 years. Glomerular filtration rate (GFR; inulin and creatinine clearances), renal plasma flow (RPF; PAH clearance), resting urinary albumin excretion (UAE) were measured and compared with indexes of metabolic control: Hb A1C and blood glucose values (mean, post-prandial and maximal excursion) on the same day. GFR (inulin clearance) and RPF were significantly increased in the diabetic group (171±31 and 778±172 ml/min per 1.73 m2) compared with controls (124±18 and 631±128 ml/min per 1.73 m2). Both parameters were strongly correlated (r=0.73;P<0.001). Creatinine clearance was not correlated to inulin clearance. Hyperfiltration (inulin clearance above 160 ml/min per 1.73 m2) was noted in 61% of the patients and was independent of diabetes duration. Five diabetic children had a UAE level above 15 g/min. No relationship could be established between UAE and any of the metabolic indexes; GFR was weakly correlated to HbA1C (r=0.35;P<0.05), to mean (r=0.35;P<0.05) and post-prandial blood glucose (r=0.37;P<0.05). In contrast, there was a strong correlation between GFR and the maximal blood excursion (r=0.62;P<0.001). The study shows that renal abnormalities can be detected with a high frequency in diabetic subjects characterized by both an early onset and a short duration of diabetes and suggests the need for a more systematic evaluation of renal parameters in this population.  相似文献   
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A review of nine adenocarcinomas of the esophagus arising in Barrett's epithelium was undertaken. We found the disease among white males disproportionately. Risk factors and incidence rate remain to be clarified. Only one patient was in a surveillance program and only he had carcinoma discovered "early." He still survives while only one of the eight whose diagnosis followed investigation of symptoms remains alive.  相似文献   
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BACKGROUND: Mixed allogeneic hematopoietic chimerism has previously been reliably achieved and shown to induce tolerance to fully MHC-mismatched allografts in mice and monkeys. However, the establishment of hematopoietic chimerism has been difficult to achieve in the discordant pig-to-primate xenogeneic model. METHODS: To address this issue, two cynomolgus monkeys were conditioned by whole body irradiation (total dose 300 cGy) 6 and 5 days before the infusion of pig bone marrow (BM). Monkey anti-pig natural antibodies were immunoadsorbed by extracorporeal perfusion of monkey blood through a pig liver, immediately before the intravenous infusion of porcine BM (day 0). Cyclosporine was administered for 4 weeks and 15-deoxyspergualin for 2 weeks. One monkey received recombinant pig cytokines (stem cell factor and interleukin 3) for 2 weeks, whereas the other received only saline as a control. RESULTS: Both monkeys recovered from pancytopenia within 4 weeks of whole body irradiation. Anti-pig IgM and IgG antibodies were successfully depleted by the liver perfusion but returned to pretreatment levels within 12-14 days. Methylcellulose colony assays at days 180 and 300 revealed that about 2% of the myeloid progenitors in the BM of the cytokine-treated recipient were of pig origin, whereas no chimerism was detected in the BM of the untreated control monkey at similar times. The chimeric animal was less responsive by mixed lymphocyte reaction to pig-specific stimulators than the control monkey and significantly hyporesponsive when compared with a monkey that had rejected a porcine kidney transplant. CONCLUSION: To our knowledge, this is the first report of long-term survival of discordant xenogeneic BM in a primate recipient.  相似文献   
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  • 1 It was first shown several years ago that the rostral part of the ventrolateral medulla (VLM) contains a high density of receptor binding sites for angiotensin II (AngII). In the present paper we briefly review recent studies aimed at determining the actions of both exogenous and endogenous angiotensin peptides in the rostral VLM, as well as their specific sites of action.
  • 2 The results of these studies have shown that angiotensin peptides can excite pressor and sympathoexcitatory neurons in the rostral VLM, but do not appear to affect non-cardiovascular neurons in this region.
  • 3 It is known that pressor neurons in the rostral VLM include both catecholamine and non-catecholamine neurons. There is evidence that, at least in conscious rabbits, both of these types of neurons are activated by AngII. The specific endogenous angiotensin peptide or peptides that affect pressor neurons in the rostral VLM have not yet been definitively identified.
  • 4 It is also possible that different angiotensin peptides may have different effects on pressor neurons in the rostral VLM, mediated by different receptors. Further studies will be needed to define these different functions as well as the specific receptors and cellular mechanisms that subserve them.
  相似文献   
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Physician advice and counseling can significantly help patients stop smoking. Consequently, we surveyed 588 of 2,207 actively practicing American pulmonary clinicians attending the 1983 Annual Meeting of the American Thoracic Society to determine what they did to help their patients stop smoking. Ninety-nine and one tenth percent of those pulmonary internists who had never smoked recorded the smoking habits of their patients and 100% advised smokers to stop. In contrast, pulmonary internists who themselves smoked cigarettes were significantly less inclined to do these two things; 84.6% and 92.3%, respectively (p less than 0.01). There was also a trend for more never smoking internists to provide additional services to patients wishing to stop smoking. Of the pulmonary internists, 86.8% wanted to learn new techniques to help their patients stop smoking. Essentially, 75% of the small sample of pediatric pulmonary specialists surveyed felt that determining whether their patients smoked or not and providing services to help them stop smoking was "not applicable" to their practice.  相似文献   
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