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91.
BACKGROUND AND AIMS: The purpose of this study was to compare the effects of exercise habituation (3-32 years, mean 13.2 years) on physical vitality among five different groups. METHODS: One hundred and two independent, community-dwelling elderly Japanese men, aged 64.6 +/- 6.6 years, were recruited as subjects. The vital age test battery consisted of various coronary heart disease risk factors and physical fitness elements. RESULTS: The results of analysis of variance revealed that vital age as an index of physical vitality was youngest in joggers (47.9 yr, N=18), intermediate in trekkers (55.8 yr, N=20) and walkers (59.1 yr, N=18), and oldest (69.6 yr, N=20) in patients with ischemic heart disease (IHD). The difference between chronological age and vital age was approximately 15 years (p<0.05) in joggers, and 8 years (p<0.05) in trekkers and walkers. The vital age of sedentary persons (N=26) was only 1.9 years (NS) younger than their chronological age, which was similar to the difference (vital age of 64.1 +/- 8.5 yr vs chronological age of 65.7 +/- 5.4 yr) previously observed in similarly aged exercising IHD patients. CONCLUSIONS: These results indicate that exercise habituation significantly affects the overall health status of most individuals, irrespective of mode of exercise. Among the three modes of exercise, jogging may be most beneficial. Furthermore, regularly exercising coronary patients may have physical vitality similar to that of sedentary men.  相似文献   
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Annual mass examination was performed between 1972 and 1997 in Tomie-town, Goto Islands, Japan, where hepatitis B virus (HBV) infection is very prevalent. In the present study, the incidence of spontaneous loss of hepatitis B surface antigen (HBsAg) in HBsAg carriers was determined in this area. Three thousand and nineteen inhabitants were tested for HBsAg two or more times in our annual surveys. Among them, 131 (4.3%) were defined as chronic HBsAg carriers based on the persistence of HBsAg for 1 or more years. These 131 subjects were followed for 12.2 ± 7.6 years. During the follow-up period, spontaneous loss of HBsAg occurred in 38 (29%) of the 131 carriers, with a yearly incidence of 2.5%. This loss was seen more frequently in carriers aged 40 years or more on enrollment than in those aged less than 40 years during the same observation periods (P = 0.0141), irrespective of sex or the results of liver function tests. The values for liver function test results were similar before and after loss of HBsAg in these carriers. Stored serum samples were available for later analysis of HBV-DNA by polymerase chain reaction in 32 carriers with loss of HBsAg. The HBV-DNA sequence was detected in 26 (81%) and 2 of the 32 carriers (6%) before and after loss of HBsAg, respectively. These results indicate that spontaneous loss of HBsAg, largely attributable to clearance of viremia, occurs age-dependently in chronic carriers. Received: July 23, 1999 / Accepted: September 24, 1999  相似文献   
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Prolonged exposure of tissues to a receptor agonist often leads to adaptive changes that limit the subsequent responsiveness of the tissue to the same agonist. Recently, we have generated rats transgenic for the metallothionein I-human arginine vasopressin (AVP) fusion gene (Tg), which produced high plasma AVP with relatively preserved renal water excretion, suggesting that there might be adaptive mechanism(s) for maintaining water and electrolyte homeostasis against chronic AVP oversecretion from the earliest stage of life. In this study, to investigate whether down-regulation of AVP V2 receptor (V2R), which could possibly be caused by long-standing high plasma AVP, participates in this adaptive mechanism(s), non-peptidic V2R antagonist OPC31260 was administered to reverse the down-regulation, and water loading was performed after V2R antagonist treatment had been withdrawn. Additionally, to confirm the down-regulation, Northern blotting analysis for V2R mRNA was carried out. Tg rats showed slightly decreased urine volume and water intake with an equivalent plasma [Na(+)] level (Tg 140.4 +/- 0.6 mEq/l; control 139.3 +/- 0.6 mEq/l) under basal conditions. After water loading using a liquid diet containing zinc, which stimulates the promoter region in the transgene, the urine increase showed only limited suppression with a dramatically increased plasma AVP level and mild hyponatremia (135.8 +/- 1.8 mEq/l) in Tg rats. When diet containing OPC31260 had been provided for 4 days until the day before the start of water loading, antidiuresis and hyponatremia (125.4 +/- 1.mEq/l) were significantly potentiated. V2R mRNA expression in kidney was significantly less in Tg rats than in control rats under basal conditions, and this suppression was restored by OPC31260 treatment to levels comparable with those of control rats. These results suggest that long-standing high plasma AVP causes V2R down-regulation, and it may play an important role in the adaptive mechanism(s) for maintaining water and electrolyte homeostasis in chronically AVP-overexpressing rats.  相似文献   
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OBJECTIVE: The novel vaso-constricting 31-amino acid-length endothelin-1 [ET-1(1-31)] is selectively produced by human mast cell chymase via its action on big ET-1. However, the pathological role of ET-1(1-31) in atherosclerosis remains unclear. The aim of this study was to clarify vasoconstrictive response and expression of ET-1(1-31) in atherosclerotic aorta. METHODS AND RESULTS: Syrian golden hamster, was used for preparing the atherosclerotic models by the administration of a high cholesterol diet (HC), treatment with the nitric oxide synthase inhibitor (Nomega-nitro-L-arginine methylester, L-NAME) alone, or both (HC and L-NAME) for 40 weeks. Early atherosclerosis was observed in the case of HC or L-NAME alone treatments respectively and severe atherosclerosis was observed in the case of combined HC and L-NAME treatment. Vasoconstriction induced by ET-1(1-31) was not altered by the atherosclerotic changes, but the expression pattern of ET-1(1-31) was different at each stage of the atherosclerotic aorta. ET-1(1-31) was observed rarely in normal aortas or in early atherosclerotic lesions, but ET-1(1-31) expression was dramatically increased in aortic neointima and adventitia in a state of atherosclerosis with severe inflammation. CONCLUSION: ET-1(1-31) might play in a role of promoting atherosclerosis, and especially be involved in inflammatory mediation during the progression of atherosclerosis.  相似文献   
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Summary 1255 cases of leukemia-lymphoma were tested between 1972 and 1984 by multiple marker analysis. Routine leukemia phenotyping was performed using standard morphological and cytochemical techniques in combination with clinical and histo-pathological information; the main emphasis was put on immunological surface marker analysis using erythrocyte rosette assays, TdT and a large panel of poly- and monoclonal antibody tests. The 1255 cases were divided into these major types and subtypes: 349 cases of ALL and related immature T- and Burkitt-lymphomas (cALL, pre B-ALL, B-ALL and Burkitt-lymphomas, T-ALL and immature, mostly leukemic T-lymphomas, Null-ALL), 454 cases of mature T- and B-cell malignancies (T-CLL, mycosis fungoides, Sezary-syndrome, T-lymphomas, B-CLL, hairy cell leukemia, multiple myeloma, B-lymphomas), 263 cases of acute myeloid leukemias (AML, AMMoL/AMoL), 182 cases of chronic myeloid leukemias (CML in chronic phase, CMoL, CML in blast crisis), 6 cases of erythroleukemia and 1 case of megakaryoblastic leukemia. A simplified classification scheme which has been used in our laboratories is presented. Phenotyping is of diagnostic, prognostic and therapeutic relevance, most evidently for patients with ALL. Routine leukemia phenotyping should be performed with highly standardized techniques and reagents and by combining information from several fields in the multiple marker analysis. New areas of leukemia research might become very useful for the routine procedure of phenotyping.Abbreviations ALL acute lymphoblastic leukemia - AML acute myeloblastic leukemia - AMMoL acute myelomonoblastic leukemia - AMoL acute monoblastic leukemia - cALL common ALL - CLL chronic lymphocytic leukemia - CML chronic myelocytic leukemia - CML-BC CML in blastic crisis - CMoL chronic monocytic leukemia  相似文献   
100.
Hypothyroidism is associated with increased morbidity from cardiovascular disease, and an increase in serum osteoprotegerin (OPG) has recently been reported to be associated with the severity of coronary heart disease and cardiovascular mortality. The present study was designed to examine whether hypothyroidism causes an increase in serum OPG, and to determine whether levothyroxine (L-T4) replacement therapy might suppress serum OPG levels in hypothyroid patients. Fifty-three hypothyroid patients with chronic thyroiditis and age- and sex-matched normal control subjects were examined for the levels of serum OPG and plasma von Willebrand factor (vWF), a vascular injury marker. Thirty-seven of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T4 replacement therapy. Baseline OPG was significantly higher in hypothyroid patients than in normal controls (4.51 +/- 0.50 vs 3.72 +/- 0.23 pmol/l (mean +/- S.E.); P = 0.0182). In multivariate analysis, baseline OPG was significantly associated with baseline levels of TSH (r = 0.280, P = 0.0162) and vWF (r = 0.626, P < 0.0001). During one year of L-T4 replacement therapy, hypothyroid patients showed a significant decrease in OPG levels from 4.35 +/- 0.51 to 3.48 +/- 0.26 pmol/l (P = 0.0166), a level comparable to normal controls. The change in serum OPG levels during L-T4 replacement therapy was significantly and independently associated in a negative fashion with baseline vWF (r = -0.503, P = 0.0014). This study suggested that the severity of hypothyroidism and vascular injury might have important independent roles in increasing the serum OPG level in hypothyroid patients. Furthermore, it was demonstrated that a sustained euthyroid state might have the potential to decrease the serum OPG level in hypothyroid patients and that the degree of vascular injury in the hypothyroid state is independently associated with a decrease in serum OPG during a 1-year normalization of thyroid function.  相似文献   
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