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Kriegler  AB; Bernardo  D; Verschoor  SM 《Blood》1994,83(1):65-71
Corticosteroids have the ability to suppress the production of growth factors and cytokines and are thus implicated in the negative regulation of hematopoiesis. We have shown that the corticosteroids, prednisolone and dexamethasone, were able to effectively protect progenitor cells in four strains of mice against cell-cycle-specific antimetabolic chemotherapy agents. The highest levels of protection against 5-fluorouracil (FU; 200 mg/kg) were achieved when two or three intraperitoneal injections of dexamethasone were administered between - 7 and +3 hours at a dose of 7.5 mg/kg/injection (optimal dose) or by continuous infusion between -4 and +20 hours. This protective effect is manifested as an increase in the number of high proliferative potential colony-forming cells that survive in the bone marrow 3 days after treatment with FU from between 0.5% and 11% to between 10% and 34% of normal. The bone marrow progenitors and blood cell numbers return to normal from 3 to 5 days and 1 to 2 days earlier, respectively. Less dexamethasone than prednisolone is required to give an equivalent protective effect, which is consistent with their anti-inflammatory potency. These findings are further evidence of the negative regulatory role played by corticosteroids, and indicate that the treatment schedules of corticosteroids during cancer therapy need to be reexamined to obtain the maximum benefit from their use.  相似文献   
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Effects of bile salts on intestinal glucose transfer differ in diverse animal preparations exposed to various bile acids. Radiolabeled glucose influx into rat jejunum in vitro was studied in buffer and compared to taurodeoxycholate, taurochenodeoxycholate, taurocholate, and deoxycholate. Jejunum was obtained from intact, bile-diverted, and colestipoltreated rats and in similar categories after abdominal x-irradiation. Taurodeoxycholate but not taurocholate inhibited glucose influx only in bile-fistula and colestipol-treated rats. Bile diversion increased and colestipol decreased glucose uptake from buffer. Added inhibitory effects of irradiation and bile salts were seen in bile-fistula animals. These data suggest that normal exposure to bile is chronically inhibiting jejunal glucose transport and that dihydroxy bile salts are responsible for this effect. They do not provide an explanation for the role of bile in the intestinal radiation syndrome.This work was supported in part by contract No. AT-(40-1) 3882 from the U.S. Atomic Energy Commission.These data were presented in part at the annual meeting of the Southern Society for Clinical Investigation, New Orleans, La. February, 1975.  相似文献   
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Mitochondrial disorders are caused by impairment of the respiratory chain. Psychiatric features often represent part of their clinical spectrum. However, the real incidence of psychiatric disorders in these diseases is unknown. The aim of this study was to evaluate psychiatric involvement in a group of patients with mitochondrial disorders and without already diagnosed mental illness. Twenty-four patients with mitochondrial disorder and without already diagnosed mental diseases have been studied by means of the mini-international neuropsychiatric interview (MINI) and the newcastle mitochondrial diseases adult scale (NMDAS). In patients with mitochondrial disease, psychiatric conditions were far more common than in general Italian population (about 60 vs. 20–25%), and included major depression, agoraphobia and/or panic disorder, generalized anxiety disorder, social anxiety disorder, psychotic syndromes. Psychiatric involvement did not seem to depend on disease progression. Large, multicenter studies are strongly needed to better characterize the natural history of mitochondrial disorders and of their psychiatric involvement. Moreover, the possibility of mitochondrial diseases should be considered in patients with psychiatric diseases. Finally, we encourage psychiatric evaluation as a routinary approach to mitochondrial patients.  相似文献   
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Oral contraceptive-induced menstrual migraine (OCMM) is a particularly severe form of migraine triggered by the cyclic hormone withdrawal. To review the efficacy of frovatriptan vs. other triptans, in the acute treatment of OCMM through a pooled analysis of three individual randomized Italian studies. With or without aura migraineurs were randomized to frovatriptan 2.5 mg or rizatriptan 10 mg (study 1), frovatriptan 2.5 mg or zolmitriptan 2.5 mg (study 2), frovatriptan 2.5 mg or almotriptan 12.5 mg (study 3). All studies had a multicenter, randomized, double-blind, crossover design. After treating 1–3 episodes of migraine in 3 months with the first treatment, patients switched to the other treatment for the next 3 months. In this analysis, the subset of 35 of the 280 women of the intention-to-treat population taking combined oral contraceptives and experiencing a migraine attack during the withdrawal phase, were analyzed. The proportion of pain free and pain relief at 2 h were 25 and 51 % with frovatriptan and 28 and 48 % with comparators (p = NS). At 24 h, 71 and 83 % of frovatriptan-treated patients and 60 and 76 % of comparator-treated patients were pain free (p < 0.05 between treatments) and had pain relief (p = NS), respectively. Relapse at 24 and 48 h was significantly (p < 0.05) lower with frovatriptan (17 and 21 %) than with the comparators (27 and 31 %). Our results suggest that, due to its sustained antimigraine effect, frovatriptan may be particularly suitable for the management of OCMM than other triptans.  相似文献   
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