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1.
The effect of chronic metabolic acidosis (0.1 g/(kg . day) X 3 days) on carbohydrate metabolism was examined with the glucose-clamp technique in 16 healthy volunteers. Hyperglycemic clamp. Plasma glucose concentration is acutely raised and maintained 125 mg/dl above the basal level. Because the glucose concentration is held constant, the glucose infusion rate is an index of glucose metabolism (M). Following NH4Cl, M decreased from 8.95 +/- 1.12 to 7.35 +/- 0.76 (P less than 0.05) despite an increased plasma insulin concentration (I) 23 +/- 9%, P less than 0.05). Consequently the M/I ratio, an index of tissue sensitivity to insulin, decreased by 32 +/- 5% (P less than 0.005). Euglycemic clamp. Plasma insulin concentration is acutely raised and maintained 101 +/- 3 microU/ml above basal and plasma glucose is held constant at the fasting level by a variable glucose infusion (M). Following NH4Cl both M and M/I decreased by 15 +/- 4% (P = 0.005) and 15 +/- 5% (P = 0.01), respectively. Metabolic acidosis had no effect on basal [3-3H]glucose production or the percent of decline (91 +/- 4%) following hyperinsulinemia. Both hyperglycemic and euglycemic clamp studies indicate that impaired glucose metabolism following metabolic acidosis results from impaired tissue sensitivity to insulin.  相似文献   
2.
OBJECTIVE: To compare the incidence rates of hypertension and non-insulin dependent diabetes mellitus in relation to ethnicity and other characteristics in a rapidly developing community. DESIGN: Prospective surveillance of a total community for five years. SUBJECTS: Cohort of 2491 men and women aged 35 to 69 years (79% response), of African, Indian and "other' (mainly Afro-European) descent. RESULTS: During surveillance, secular increases occurred in fasting blood glucose concentrations in both sexes and in body mass index (BMI) in men, with apparent secular reductions in systolic blood pressure in both sexes. Incidence rates of hypertension did not differ significantly with ethnicity, ranging between 33 and 41 per 1000 person-years in men and between 27 and 32 per 1000 person-years in women. In men, the incidence of diabetes (per 1000 person-years) in Indians (24) was significantly higher than in Africans (13) and others (11). In women, the diabetic incidence was similar to that for men in Indians (23) and Africans (14), but in others was twice that in men (21). In both sexes, weight gain was an important risk factor for hypertension, whereas risk of diabetes increased with BMI at baseline. The increased risk of diabetes in Indians among men was independent of baseline BMI and blood glucose. CONCLUSION: Apart from the increased risk of diabetes in Indians, ethnicity had no significant influence on incidence rates of hypertension and diabetes in Trinidad. Secular increases in blood glucose in both sexes and in BMI in men probably contributed to the concurrent increase in mortality from coronary heart disease in this community.  相似文献   
3.
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
4.
Guit  GL; Shaw  PC; Ehrlich  J; Kroon  HM; Oudkerk  M 《Radiology》1985,154(2):305-306
A case of mixed connective tissue disease (MCTD) is presented in which mediastinal lymphadenopathy was the most prominent radiological finding detected by plain chest radiographs and computed tomography. Pulmonary arterial hypertension, which is a rare and often fatal complication of MCTD, also developed in this patient.  相似文献   
5.
6.
High-dose (HD) cytosine arabinoside (ARA-C) is more effective treatment than conventional-dose ARA-C regimens for patients with relapsed acute nonlymphocytic leukemia (ANLL). We report here that HD ARA-C given during the first remission of ANLL has resulted in long remission durations and a high proportion of patients who survive more than three years free of disease. From August 1979 to September 1983, 36 adult patients with ANLL in first remission received one to three courses of HD ARA-C (3 g/m2 by one-hour infusion every 12 hours for 12 doses on days 1 through 6) alone or with daunorubicin (30 mg/m2 for two or three doses on days 7 through 9). Three patients died of sepsis or hemorrhage during consolidation, and 14 patients have relapsed from five to 48 months after diagnosis. The remaining 19 patients are in continued complete remission (CCR) from 11 to 62 months. Denoting all deaths in remission as relapse, the actuarial probability of CCR is 42% at 62 months, with an apparent plateau in the survival curve. Of the first 22 patients treated, ten remain in CCR from 37 to 62 months with no therapy for at least three years. Due to its heightened anti-leukemic activity, HD ARA-C allows brief but effective consolidation of ANLL in first remission, with long-term disease-free survival comparable to other approaches.  相似文献   
7.
Serum high-density lipoprotein (HDL) cholesterol, testosterone and sex-hormone-binding globulin (SHBG) were measured in 300 men, aged 35-64 years, of African and Indian descent who represented a 40% sample of participants in a community survey of coronary heart disease in Trinidad. Free testosterone was calculated from total testosterone and SHBG. In 113 men, HDL2 and HDL3 cholesterol were measured by a precipitation technique. Indian men had a significantly lower HDL-cholesterol concentration than African men (P = 0.003), which is known to be due to a reduction in the HDL3 fraction (demonstrable only in younger men in the subsample drawn for this study). Testosterone did not differ with ethnic group, but SHBG was reduced in Indians (P = 0.03). After allowance for age, ethnic group, alcohol consumption and smoking habit, HDL cholesterol was associated positively with SHBG (P = 0.025) but was not related significantly to either total testosterone or its free and bound components. Serum HDL2 cholesterol was associated positively and independently with SHBG (P = 0.001) and total and bound testosterone (P = 0.002), whereas HDL3 cholesterol showed no significant associations with these factors. Neither SHBG or testosterone afforded an explanation for the relatively low HDL and HDL3 cholesterol concentrations in Indian men.  相似文献   
8.
胰岛素样生长因子Ⅰ与肝纤维化   总被引:1,自引:1,他引:1  
胰岛素样生长因子I(IGF-I)是体内普遍存在的多肽,循环系统中IGF-I主要来源于肝脏.在垂体生长激素的调控下,IGF-I对多种细胞如成纤维细胞、成骨细胞、平滑肌细胞等的有丝分裂均有调节作用.目前观点认为肝星状细胞(HSC)活化后可分泌大量胶原纤维,是肝纤维化时细胞外基质的主要来源.实验表明 IGF-I能够促进体外培养HSC增殖、活化并抑制其凋亡.而体内研究发现,肝硬化患者血清IGF-I浓度显著下降,外源性小剂量IGF-I 注射能够改善肝功能,为肝纤维化的治疗提供了新的理念.  相似文献   
9.
Ganesan  TS; Min  GL; Goldman  JM; Young  BD 《Blood》1987,70(3):873-876
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone.  相似文献   
10.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
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