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Anxiety levels in a sample of 65 long-term cancer survivors were assessed in a study of the effects of a planned discharge from an oncology clinic. Thirty-one percent of patients scored > or = 8, and 12% > or = 11 on the anxiety subscale of the Hospital Anxiety and Depression Scale (HADS), indicating that anxiety rates in patients in long-standing remission do not greatly differ from patients with active disease. Despite the provision of continued support and guaranteed fast-access return to the clinic if necessary, 28% of patients refused to be discharged. Fear that recurrence would not be detected was the reason most frequently cited. Seventy-five percent of these patients were HADS anxiety cases. A second assessment 4-5 months later of the 41 patients who were discharged showed a slight, but non-significant increase in anxiety rates suggesting that anxiety in cancer survivors may be persistent and not related to clinic attendance. 相似文献
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Ten groups of 14 immunosuppressed NMRI-mice (nu/nu) were raised and kept under germ-reduced conditions. The control animals were fed a germ-reduced diet, nine other groups received the same diet with selegiline (CAS 14611-51-9, Deprenyl) or lipoic acid (thioctic acid, CAS 62-46-4) admixed at various amounts. The 50% survival rate, the total life span of each group and the areas under the curves were determined to evaluate life expectancy as compared to the controls. The racemate of lipoic acid at high dosage (350 mg/kg body weight) reduced the life span significantly. The S(-)-enantiomer of lipoic acid (75 mg/kg body weight) increased the 50% survival rate, whereas the physiologic R(+)-enantiomer (9 mg/kg body weight) expanded the total life span of its group. Alteration of only one out of three parameters was not considered significant. All other groups except for one did not differ from controls: only animals which obtained 75 micrograms selegiline per kg of body weight and per day exerted increased life expectancies by all three parameters. This group exhibited also in statistical evaluation a significantly (p < 0.05) prolongated survival time up to about 200% as compared to the control animals. 相似文献
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Minimal model analysis with the frequently sampled intravenous glucose tolerance test provides an effective way to measure two important metabolic parameters in vivo under non-steady-state conditions: glucose effectiveness (SG) and insulin sensitivity (SI). Two questions regarding the validity of SG and SI have recently emerged. First, SG from the minimal model is suspected to be overestimated. Second, the occurrence of SI values indistinguishable from zero ("zero-SI") is not negligible in large clinical studies, and its physiological meaning is uncertain. In this study, we examined the significance of the assumed single-compartment glucose distribution embedded in the minimal model on the estimation of SG and SI. A more accurate two-compartment model was constructed by incorporating insulin action on hepatic glucose output and uptake into a previously validated construction. The two-compartment results were compared with the one-compartment minimal model results. It was shown that the one-compartment assumption contributes to a systematic deviation of SG (slope = 0.54, y-intercept = 0.014 min[-1]; n = 195 simulations). However, SG from the minimal model was linearly correlated to SG determined from the two-compartment model (r = 0.996). The one-compartment assumption also contributed to the occurrence of zero SI values for insulin-resistant subjects. A similar linear relationship was found between SI estimated by both the minimal model and the two-compartment model (slope = 0.58, y-intercept = -0.57 x 10[-4] min[-1] per pU/ml, r = 0.998). In conclusion, SG and SI from the minimal model are not necessarily equivalent to values emanating from the more accurate two-compartment model. However, the very high correlation between one- and two-compartment results suggests that the minimal model-derived SG and SI are dependable indexes of in vivo glucose effectiveness and insulin sensitivity. Minimal model analysis' advantages of simplicity, minimal invasiveness, reasonable reflection of non-steady-state glucose kinetics, and cost-effectiveness could in many cases outweigh the structural bias introduced by the model simplification. 相似文献
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P Malik TC Fisher LL Barsky L Zeng P Izadi AL Hiti KI Weinberg TD Coates HJ Meiselman DB Kohn 《Canadian Metallurgical Quarterly》1998,91(8):2664-2671
Hemoglobinopathies, such as beta-thalassemias and sickle cell anemia (SCA), are among the most common inherited gene defects. Novel models of human erythropoiesis that result in terminally differentiated red blood cells (RBCs) would be able to address the pathophysiological abnormalities in erythrocytes in congenital RBC disorders and to test the potential of reversing these problems by gene therapy. We have developed an in vitro model of production of human RBCs from normal CD34(+) hematopoietic progenitor cells, using recombinant growth factors to promote terminal RBC differentiation. Enucleated RBCs were then isolated to a pure population by flow cytometry in sufficient numbers for physiological studies. Morphologically, the RBCs derived in vitro ranged from early polylobulated forms, resembling normal reticulocytes to smooth biconcave discocytes. The hemoglobin pattern in the in vitro-derived RBCs mimicked the in vivo adult or postnatal pattern of beta-globin production, with negligible gamma-globin synthesis. To test the gene therapy potential using this model, CD34(+) cells were genetically marked with a retroviral vector carrying a cell-surface reporter. Gene transfer into CD34(+) cells followed by erythroid differentiation resulted in expression of the marker gene on the surface of the enucleated RBC progeny. This model of human erythropoiesis will allow studies on pathophysiology of congenital RBC disorders and test effective therapeutic strategies. 相似文献