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71.
Novel intestinal polypeptide YY (PYY) and pancreatic polypeptide (PP) were infused in fed anaesthetized rats. The peptides (10 and 100 pmol/kg · min) were administered during 30 min, alone, together with glucose or together with arginine. Plasma concentrations of glucose, insulin and glucagon were measured. At the dose of 10 pmol/kg · min the peptides had no effect. PP at the dose of 100 pmol/kg · min slightly augmented basal, but had no effect on stimulated insulin and glucagon release. PYY at the dose of 100 pmol/kg · min was without effect on basal insulin and glucagon levels and on glucose-induced insulin release, but exerted an inhibitory effect on arginine-induced secretion of both insulin and glucagon. It is unlikely that PYY and PP can affect secretion of insulin and glucagon via blood circulation. The potential capability of high doses of PP to affect insulin and glucagon secretion suggests that this peptide may exert direct (paracrine) effects on the pancreatic A-and B-cells  相似文献   
72.
The ontogeny of alkaline phosphatase in the bursa of Fabricius was studied by histochemical and biochemical methods. According to the quantitative determinations, the activity of alkaline phosphatase increased from the 11th to 17th day of incubation--that is, during the time of the lymphoid follicle formation in the developing bursa. The activity was localized in the mesenchymal tissue surrounding the lymphoid follicles. Testosterone given in ovo prevented the appearance of alkaline phosphatase in the bursal mesenchyme but had no effect on the activity of the embryonic liver. In contrast, in ovo treatment with cyclophosphamide had no effect on the alkaline phosphatase in the bursa. By using transplantation of embryonic bursal stem cells, it was further shown that, in contrast to cyclophosphamide, testosterone destroys the capacity of the bursa to serve as a differentiation site for the B-cell lineage. The results indicate that testosterone affects the stromal cells of the bursa, whereas cyclophosphamide destroys only the lymphoid population undergoing differentiation and leaves the bursal stroma intact.  相似文献   
73.
Atrial natriuretic factor (ANF) was determined in pulmonary and systemic arterial plasma during diagnostic left and right heart catheterization in twenty-three patients. In twenty of these patients ANF was subsequently measured in systemic arterial plasma during nuclear magnetic resonance (NMR) imaging of the heart with computation of left heart chamber volumes and left ventricular mass. Left ventricular end-diastolic pressure was the strongest independent predictor of pulmonary arterial plasma ANF, whereas cardiac index best predicted aortic plasma ANF. Both pulmonary and aortic plasma ANF correlated with systolic and diastolic pulmonary arterial pressure, left ventricular end-diastolic pressure and cardiac index. Left atrial volume index and left ventricular mass index did not correlate with systemic arterial plasma ANF whereas a positive linear correlation between left ventricular end-diastolic volume index and ANF could be demonstrated (r = 0.61, P less than 0.01). Left ventricular end-diastolic volume index was the most important independent predictor of systemic arterial plasma ANF. Systemic arterial plasma ANF might be a simple marker of left ventricular dilatation in patients with heart disease.  相似文献   
74.
Summary. The Universities of Kuopio and Tampere in collaboration with the Ministry of Social Affairs and Health and Finnish Medical Association carried out the 'Junior Physician 88' study in 1988, the purpose of which was to shed further light on the life situation and future plans of young doctors and their views concerning undergraduate and postgraduate medical education. The study concerned all the doctors registered during the years 1977–1986 in Finland (   n = 5208  ). After randomization, a postal questionnaire was sent to one half (   n = 2631  ) of these doctors. After the first reminder letter, 1745 questionnaires (66.3%) were returned. According to the views of the respondents undergraduate hospital teaching was adequate but the teaching of practice in health centres, school health care, team-work, health care of the elderly, home health care, rehabilitation, environmental health care and administration did not meet the professional needs of doctors. All doctors were satisfied with the hospital teaching in their undergraduate curriculum. However, only the doctors who graduated from the two modern universities in Kuopio and Tampere were satisfied with their undergraduate health centre teaching.  相似文献   
75.
Abstract. Objectives. To study the infarct size and mortality in patients with non-insulin-dependent diabetes mellitus (NIDDM) and in non-diabetic subjects with their first acute myocardial infarction. Design. Seven year follow-up study of large representative cohorts of patients with non-insulin-dependent diabetes mellitus and non-diabetic subjects (study 1) and the FINMONICA acute myocardial infarction register study in 1988-89 (study 2). Setting. Populations of the districts of the Kuopio University Hospital and Turku University Central Hospital (study 1). Populations of Kuopio and North Karelia provinces and Turku/Loimaa area (study 2). Subjects. Study 1: 1059 patients with non-insulin dependent diabetes mellitus and 1373 non-diabetic subjects aged 45–64 years at baseline; during the follow-up 166 patients with non-insulin-dependent diabetes mellitus (91 men and 75 women) and 30 non-diabetic subjects (25 men and five women) were hospitalized for their first acute myocardial infarction. Study 2: 1622 patients aged 25–64 years hospitalized for their first acute myocardial infarction; 144 patients (90 men and 54 women) had non-insulin-dependent diabetes mellitus and 1153 (890 men and 263 women) were non-diabetic. Main outcome measures. The infarct size was assessed on the basis of maximum levels of serum cardiac enzymes (studies 1 and 2) and QRS-score (study 1). Results. No differences were found in maximum levels of serum cardiac enzymes between diabetic and non-diabetic patients. Similarly QRS-score gave no suggestion of a difference in infarct size between diabetic and non-diabetic patients. In both studies mortality before hospital admission was similar in diabetic and non-diabetic patients, but mortality within 28 days from hospital admission was twice as high in diabetic patients as in non-diabetic patients. Cardiac failure was the main cause of death significantly more often in diabetic patients than in non-diabetic patients (study 2). Conclusions. Poorer prognosis of acute myocardial infarction in diabetic patients appears not to be explained by a larger infarct size but probably by adverse effects of the diabetic state itself on myocardial function.  相似文献   
76.
The fatty acid composition of serum phospholipids and cholesteryl esters was analysed in 71 male patients with angiographically defined three-vessel coronary artery disease (CAD) selected for a coronary bypass operation. Their 71 control subjects were matched according to age, sex, smoking, relative weight, and absence of CAD. The concentrations of fatty acids, 14:0, 16:0 and 16:1 of the serum phospholipids, were significantly (P less than 0.01, P less than 0.05 and P less than 0.01, respectively) higher in CAD patients than in the controls. On the other hand, linoleic (18:2 omega 6), linolenic (18:3 omega 3) and arachidonic (20:4 omega 6) acids were at a significantly lower level in the patients when compared to the controls. The polyunsaturated/saturated fatty acids (P/S) ratio in serum phospholipids was significantly (P less than 0.01) lower in the patients than in the controls. In the cholesteryl ester fraction the results paralleled those of the phospholipids. Significant correlations were obtained between the polyunsaturated fatty acids and the high density lipoprotein cholesterol or apolipoprotein A-I in the control subjects but most of these correlations were absent in the patients. Our present results further support the importance of linoleic acid in the protection against atherosclerosis. However, no unequivocal evidence on the possible beneficial effect of long-chain omega 3-fatty acids in comparison with omega 6-acids was obtained.  相似文献   
77.
78.
BACKGROUND: In adults with HIV infection, lipodystrophy syndrome may develop, characterized by peripheral wasting in the extremities, central obesity, hyperlipidemia, and insulin resistance. This syndrome occurs in HIV-positive pediatric patients who take protease inhibitors (PIs). However, the full characteristics of the syndrome in this population is not fully understood. OBJECTIVE: To evaluate the association between the use of PIs and the occurrence of lipodystrophy in HIV-infected children. METHODS: Pediatric patients attending an outpatient HIV clinic between 1994 and 2000 were prospectively enrolled. All patients were between 1 and 17 years of age and had received a PI for at least 1 month. The medical records were reviewed monthly for 3 months before PI therapy was started and then monthly for 36 months. At each evaluation, serum total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, triglycerides, and blood glucose concentrations were recorded, as well as physician-documented physical examination findings including subcutaneous fat in the arms, face, and legs, and abdominal girth. Baseline clinical and laboratory data were compared with follow-up data using a paired t-test. RESULTS: Twenty-one pediatric patients received a PI. Of these, 2 developed lipodystrophy, one at 15 months and one at 18 months after PI therapy was started. Neither child had had lipodystrophy before therapy. Twelve children who were taking ritonavir or nelfinavir, including 1 who developed lipodystrophy, developed abnormally high total cholesterol and triglyceride blood concentrations. All patients receiving indinavir also experienced a substantial increase in their triglyceride concentrations at follow-up evaluations, but no significant increases in total cholesterol occurred. Blood glucose concentrations were not significantly different between baseline and follow-up examinations in our patients. CONCLUSIONS: Lipodystrophy may occur in some HIV-infected children receiving PIs, and dyslipidemias may also develop in some patients taking these drugs.  相似文献   
79.
ABSTRACT. Evidence for the association between Coxsackie B virus infections and myocardial infarction was studied in a prospective follow-up examination. Using the micro neutralization test, 9 (15%) of 59 patients with acute myocardial infarction and 1 (2.6%) of 38 control patients showed a fourfold, or higher, antibody increase in paired serum samples against Coxsackie B1-5 viruses. This difference is significant (p≤0.05). None of the patients or controls revealed symptoms of a viral infection during the blood sampling. Virus isolation from throat and feces was negative in all patients and controls. This finding agrees with some previous studies suggesting that the Coxsackie B group may in some cases have a causal role in myocardial infarction, or may act as a triggering factor.  相似文献   
80.
OXIDATION OF GLUCOSE and D-B-OH-BUTYRATE BY THE EARLY HUMAN FETAL BRAIN   总被引:2,自引:0,他引:2  
Abstract. Adam, P. A. J., Räihä, N., Rahiala, E.-L. and Kekomäki, M. (Departments of Pediatrics, Case Western Reserve University at Cleveland Metropolitan General Hospital, Cleveland, Ohio USA, and the University of Helsinki at the Children's Hospital, Helsinki, Finland). Oxidation of glucose and D-B-OH-butyrate by the early human fetal brain. Acta Paediatr Scand, 64:17, 1975.–The isolated brains of 12 previable human fetuses obtained at 12 to 21 weeks' gestation, were perfused through the interval carotid artery with glucose (3 mM) and/or DL-B-OH-butyrate (DL-BOHB), 4.5 mM, plus tracer quantities of either glucose-6-14C (G614C) or β-OH-butyrate-3-14C (BOHB314C). Oxidative metabolism was demonstrated by serial collection of gaseous 14CO2 from the closed perfusion system, and from the recirculating medium. Glucose and BOHB were utilized at physiological rates as indicated (mean ±SEM): G614C at 0.10±0.01 μmoles/min g brain (n=7) or 17.5±1.9 μmoles/ min kg fetus; and BOHB314C at 0.16±0.05 μmoles/min g (n=5) or 27.3±7.4 μmoles/ min kg. Based on fetal weight, glucose metabolism by brain apparently accounted for about 1/3 of basal glucose utilization in the fetus. On a molar basis BOHB314C was taken up at 1.47 times the rate of G614C. Both BOHB314C and G6 14C were converted to 14C02. The rate of BOHB314C conversion to 14CO2 was equal to its rate of consumption, and exceeded the conversion of glucose to CO2 because 45% of the G614C was incorporated into lactate-14C. Accordingly, both substrates support oxidative metabolism by brain; and BOHB is a major potential alternate fuel which can replace glucose early in human development.  相似文献   
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