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61.
62.
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   
63.
Ho  CP; Kim  RW; Schaffler  MB; Sartoris  DJ 《Radiology》1990,176(1):171-173
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   
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66.

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   
67.
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   
68.
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   
69.
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   
70.
Apoptosis, or programmed cell death, is a general mechanism for removal of unwanted cells from the immune system. It is characterized by chromatin condensation, a reduction in cell volume, and endonuclease cleavage of DNA into oligonucleosomal length fragments. Apoptosis is also accompanied by a loss of membrane phospholipid asymmetry, resulting in the exposure of phosphatidylserine at the surface of the cell. Expression of phosphatidylserine at the cell surface plays an important role in the recognition and removal of apoptotic cells by macrophages. Here we describe a new method for the detection of apoptotic cells by flow cytometry, using the binding of fluorescein isothiocyanate-labeled annexin V to phosphatidylserine. When Burkitt lymphoma cell lines and freshly isolated germinal center B cells are cultured under apoptosis inducing conditions, all cells showing chromatin condensation strongly stain with annexin V, whereas normal cells are annexin V negative. Moreover, DNA fragmentation is only found in the annexin V-positive cells. The nonvital dye ethidium bromide was found to stain a subpopulation of the annexin V-positive apoptotic cells, increasing with time. Our results indicate that the phase in apoptosis that is characterized by chromatin condensation coincides with phosphatidylserine exposure. Importantly, it precedes membrane damage that might lead to release from the cells of enzymes that are harmful to the surrounding tissues. Annexin V may prove important in further unravelling the regulation of apoptosis.  相似文献   
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