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71.
72.
H M Payne-Robinson J F Doherty M H Golden D T Simeon 《The West Indian medical journal》1990,39(4):218-224
The effect of a controlled stress (DPT inoculation) on the hormonal control of glucose homeostasis was investigated in children nutritionally rehabilitated from severe malnutrition. The age range of the 15 children studied was 6-26 months. Plasma insulin (INS), growth hormone (GH) and interleukin-1 (IL-1) were measured by radioimmunoassay; plasma glucose (GLU) by a glucose oxidase method; and red cell insulin binding (%SB) was determined, using A-14 monoiodinated insulin. Measurements were made on two occasions: (T-0) at 10 a.m., 12 hr before DPT inoculation, and (T-36) 36 hr. after inoculation. On both occasions, 4 hr post-prandial blood samples were used, and the mean body temperature (T) on the day of the test was determined. Red cell insulin binding (%SB) was significantly higher at T-36 than at T-0 (16.8 +/- 1.7 vs 12.1 +/- 1.2 (14), p = 0.005). (Results were expressed as mean +/- SEM, numbers of paired observations in parentheses). The higher %SB after DPT was accompanied by an increase in the number of receptor sites (S) (29.05 +/- 6.5 vs 15.6 +/- 2.5 (14), p = 0.025). However, insulin receptor affinity (K x 10(9) M-1) was decreased (0.7 +/- 0.1 vs 1.5 +/- 0.3 (14), p = 0.008). There were no significant differences in the plasma levels of insulin, glucose and interleukin-1, but plasma growth hormone (microU/ml) was increased after DPT, (18.0 +/- 3.0 vs. 11.5 +/- 1.2 (13), p = 0.04). Body temperature (degree C) was also significantly increased after DPT, (99.6 +/- 0.4 vs. 98.3 +/- 0.2 (14), p = 0.006).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
73.
Accuracy of dual-energy radiographic absorptiometry of the lumbar spine: cadaver study 总被引:1,自引:0,他引:1
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001). 相似文献
74.
75.
目的:骨髓基质干细胞移植到心肌梗死的瘢痕心肌组织中可以改善心功能,但以心电图为观察指标的研究不多。实验观察骨髓基质干细胞移植对正常和心肌梗死大鼠心电图及心功能的影响。方法:实验于2004-01/2005-03在哈尔滨医科大学完成。①实验动物:选取4周龄雄性Wistar大鼠80只,随机数字表法分为梗死移植组、正常移植组、梗死非移植组、正常非移植组,20只/组。另选取7d龄Wistar雄鼠30只作为骨髓基质干细胞的来源。②实验方法:采用密度梯度离心法获取鼠骨髓基质干细胞,配成1×109L-1的细胞悬液,使用5-氮胞苷体外诱导培养3~4周,移植前24~48h行Brdu标记。取载有细胞的盖玻片,测定钙释放时将20mmol/L的caffeine快速加在细胞表面。梗死移植组、梗死非移植组大鼠建立心肌梗死模型。造模4周后,梗死移植组将0.25mL诱导的骨髓基质干细胞悬液注射至大鼠心肌梗死后的瘢痕组织,正常移植组同法将骨髓基质干细胞悬液注射至正常心肌组织,梗死非移植组、正常非移植组注射等量不含骨髓基质干细胞的培养液基质。③实验评估:观察骨髓基质干细胞的诱导分化情况及其植入后在瘢痕心肌组织中的生存状态。测定细胞内钙离子浓度。记录术前、冠脉结扎后即刻/细胞移植即刻、术后4周的心电图变化。检测术后4周的超声和血流动力学指标变化。结果:80只大鼠均进入结果分析。①骨髓基质干细胞的诱导分化及其植入后的生存状态:5-氮胞苷诱导3周后,骨髓基质干细胞表达肌钙蛋白Ⅰ和肌凝蛋白重链,细胞内有丰富的肌丝和Z线,细胞器较多。植入4周后在心肌瘢痕组织中分化为心肌细胞。②细胞内钙离子浓度:两组细胞在caffeine刺激下钙离子的释放均呈波峰状,但诱导组应用caffeine后钙离子浓度降低且低于基础状态,钙释放受到抑制,未诱导组不受影响。③心电图观察:与术前比较,梗死移植组QRS波变窄,R波降支出现正常顿挫波,未见显著心律失常。④超声检测及血流动力学分析:术后4周,与梗死非移植组比较,梗死移植组左室收缩末压、左室射血分数和压力变化速率最大值均显著升高(P<0.05或0.01)。结论:骨髓基质干细胞体外诱导后能分化为心肌样细胞,植入到瘢痕心肌组织中生存、增殖良好,可改善心电图及心肌弹性,从而改善心肌梗死大鼠的心功能。 相似文献
76.
77.
Denis Libeert Dimitri Declercq Simeon Wanyama Muriel Thomas Sabine Van daele Frans De Baets Stephanie Van Biervliet 《Journal of cystic fibrosis》2018,17(2):264-270
Background
Long-term effect of enteral tube feeding (ETF) in cystic fibrosis (CF) remains equivocal.Methods
A Belgian CF registry based, retrospective, longitudinal study, evaluated the pre- and post- ETF (n?=?113) clinical evolution and compared each patient with 2 age, gender, pancreatic status and genotype class-matched controls.Results
At baseline ETF had a worse BMI z-score (p?<?0.0001) and FEV1% (p?<?0.0001) compared to controls. Patients eventually receiving ETF, had already a significant worse nutritional status and pulmonary function at first entry in the registry. Both parameters displayed a significant decline before ETF-introduction. ETF had more hospitalization and intravenous antibiotic (IVAB) treatment days (p?<?0.0001). After ETF introduction hospitalizations and IVAB decreased significantly. After ETF-introduction BMI z-score recuperated towards the original curve before the decline, but remained below the controls. Starting ETF had no effect on rate of height gain in children. The pre-index FEV1 decline (?1.52%/year (p?=?0.002)) stabilized to +0.39%/year afterwards. Controls displayed decline of ?0.48%/year (p?<?0.0001).Conclusion
ETF introduction improved BMI z-score and stabilized FEV1, associated with less hospitalizations and IVAB treatments. Higher mortality and transplantation in the ETF cases, leading to drop-outs, made determination of the effect size difficult. 相似文献78.
The separation and evaluation of puric bases and their nucleosides and nucleotides by thin-layer chromatography 总被引:1,自引:0,他引:1
J J Chivot M J Leibrandt H L Rouvroy J Simeon J P Caen 《Clinica chimica acta; international journal of clinical chemistry》1974,53(1):69-77
A method is described of thin-layer chromatography and liquid scintillation suitable for the separation and the evaluation of nucleotides, nucleosides and puric bases.The procedure employs PEI-cellulose plates with migration in two dimensions. The identification of the separated constituents utilizes radioactivity of 14C or UV light.The radioactive compounds are evaluated by liquid scintillation counting.This technique offers ease of manipulation, use of small quantities of material, highly consistent and reproducible results and good separation of the individual compounds.application of this technique to a plasma system is proposed.s method enables a present study to be made of the metabolism of platelets in our laboratory. 相似文献
79.
Summary AIM OF THE STUDY: To establish the prevalence of vertebral fractures according to age groups, sex and vertebral level in a sample of a Croatian urban population aged 50. We also tried to establish how many people had been diagnosed with osteoporosis by their family physician. PARTICIPANTS AND METHODS: Lateral thoracic and lumbar spinal radiographs were obtained in 425 ambulatory people (156 men and 269 women) aged 50 and living in the community as a random sample of the City of Zagreb (Croatia) population. An interviewer-administered questionnaire was used to obtain information on prior traumatic vertebral fractures and whether the person had been diagnosed with osteoporosis. Vertebral fractures in the population sample were defined using the morphometric method proposed by McCloskey et al., and normal values of the ratios of dimensions in non-fractured vertebrae with the iterative algorithm described by Melton et al. RESULTS: The prevalence of individuals with vertebral fractures was 11.8% (15.8% of men and 9.7% of women), ranking Zagreb mid-scale among other European cities. The prevalence of individuals with vertebral fractures rose with age. Sixty-nine (1.24%) of 5525 analysed vertebrae had been fractured. The most common fractures were those of lower thoracic and upper lumbar vertebrae. The elderly tend to sustain multiple fractures. Forty-one (9.6%) people had been previously diagnosed as having osteoporosis. Extrapolation to the Croatian population implies that approximately 90,000 men and 77,000 women aged 50 have vertebral fractures. CONCLUSION: Vertebral osteoporotic fractures are common in the Croatian population aged 50; however, awareness of osteoporosis appears to be low. 相似文献
80.
Leptin reverses insulin resistance and hepatic steatosis in patients with severe lipodystrophy 总被引:35,自引:0,他引:35
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Petersen KF Oral EA Dufour S Befroy D Ariyan C Yu C Cline GW DePaoli AM Taylor SI Gorden P Shulman GI 《The Journal of clinical investigation》2002,109(10):1345-1350
Lipodystrophy is a rare disorder that is characterized by selective loss of subcutaneous and visceral fat and is associated with hypertriglyceridemia, hepatomegaly, and disordered glucose metabolism. It has recently been shown that chronic leptin treatment ameliorates these abnormalities. Here we show that chronic leptin treatment improves insulin-stimulated hepatic and peripheral glucose metabolism in severely insulin-resistant lipodystrophic patients. This improvement in insulin action was associated with a marked reduction in hepatic and muscle triglyceride content. These data suggest that leptin may represent an important new therapy to reverse the severe hepatic and muscle insulin resistance and associated hepatic steatosis in patients with lipodystrophy. 相似文献