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141.
This retrospective study describes the outcome of patients with chronic myeloid leukaemia after allografting using dose-reduced conditioning with fludarabine and busulphan. Forty-four Philadelphia chromosome (Ph)-positive patients were transplanted in nine German centres; 26 patients were in chronic phase, 11 in accelerated phase and seven in blast crisis. Thirty-four patients achieved complete remission, with 18 alive and disease-free at a median follow-up of 562 d (range 244-922 d). Grade II-IV acute graft-versus-host disease (GVHD) incidence was 43%. Twenty patients died, 15 of causes unrelated to relapse. Risk factors predisposing to graft failure by univariate analysis were an unrelated donor (8/23 compared with a related donor 2/21, P = 0.07) and interferon therapy within 90 d of transplant (4/6 versus 3/17, P = 0.025). At the last follow-up, of 31 patients for whom molecular or cytogenetic data were available, 16 (52%) were polymerase chain reaction-negative, and seven (23%) were Ph-negative by fluorescent in situ hybridization. These findings demonstrate that dose-reduced conditioning with fludarabine and busulphan provides durable engraftment and a low rate of relapse. However, in this population, many of whom were not eligible for high-dose conditioning due to age, reduced performance status, previous complications or extensive pre-treatment, these data highlight the need for effective anti-infectious and GVHD prophylaxis. In addition, this study supports the discontinuation of interferon therapy at least 90 d before transplant  相似文献   
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Growing teratoma syndrome (GTS) is rare and can mimic disease recurrence in patients with a history of immature teratoma. Benign hypermetabolic lymphadenopathy found on staging and surveillance computed tomography (CT) and positron emission tomography (PET) may lead to the presumption of metastatic malignancy. We report a case of a 38 year old with mixed mature and immature teratomas who developed new peritoneal masses after adjuvant chemotherapy despite a normalization of tumor markers. In addition to low FDG uptake observed in these peritoneal masses, a PET scan showed hypermetabolic lymphadenopathy and pulmonary and spleen lesions suggesting widespread metastases. Subsequent surgical resection confirmed a mixed pathology with GTS and sarcoidosis. We reviewed the current literature evidence of GTS and sarcoidosis as a benign cause of lymphadenopathy in cancer patients. We emphasize the importance of a tissue diagnosis before instituting therapy for presumed cancer recurrence to avoid potentially fatal diagnostic traps and management errors. A multiple disciplinary team approach is imperative in managing patients with suspected recurrent immature teratomas.  相似文献   
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The effect of varying the fatty acid composition of the lipid components of the diet on the activity of epoxide hydratase in the rat liver and intestinal mucosa has been studied. Feeding a 10% cod liver oil diet (containing 18% C20:5 and 11% C22:6) resulted in a 3-fold increase in epoxide hydratase activity in the liver and a 1.6-fold increase in the intestine compared to rats fed a fat-free diet. The activity of epoxide hydratase in rats fed a cod liver oil diet was significantly greater than that for the group fed a lard diet (containing mainly saturated and mono-unsaturated fatty acids) containing the same quantity of vitamin E. Thus, the enhancing effect of the cod liver oil diet was due to the polyunsaturated fatty acids in this oil. Dietary corn oil (58% C18:2) also stimulated epoxide hydratase activity in the liver but not in the intestine. Vitamin E levels of up to 500 mg/kg diet were ineffective at inducing epoxide hydratase activity in both the liver and intestine. Significant changes in the fatty acid composition of hepatic and intestinal microsomes took place when rats were fed diets of different fatty acid composition. These changes were such that the proportions of polyunsaturated fatty acids in the microsomal fractions reflected the amounts of these fatty acids in the dietary fat. Hepatic epoxide hydratase activity was found to be positively correlated to the proportion of polyunsaturated fatty acids in the microsomal fractions of the liver.  相似文献   
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The 12 isomeric phenols of benzo(a)pyrene were tested for their ability to inhibit the mutagenic activity of (+/-)-7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene [B(a)P 7,8-diol-9,10-epoxide-2], an ultimate mutagenic and carcinogenic metabolite of benzo(a)pyrene. 3-Hydroxybenzo(a)pyrene [3-HO-B(a)P], a major metabolite of benzo(a)pyrene, was the most potent antagonist tested. Approximately 3 nmol of 3-HO-B(a)P, 14 nmol of 10-HO-B(a)P, and 5-8 nmol of 1-, 2-, 4-, 5-, 6-, 7-, 8-, 9-, 11-, and 12-HO-B(a)P inhibited the mutagenic activity of 0.05 nmol of B(a)P 7,8-diol-9,10-epoxide-2 by 50% in Salmonella typhimurium strain TA 100. The importance of the phenolic group for antimutagenic activity was indicated by the lack of antimutagenic activity of benzo(a)pyrene itself. 3-HO-B(a)P also inhibited the mutagenic activity resulting from the metabolic activation of benzo(a)pyrene and (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene by rat liver microsomes. This inhibition may have resulted from an effect of 3-HO-B(a)P on the metabolic activation of these carcinogens and/or from a direct effect on the action of B(a)P 7,8-diol-9,10-epoxide-2. In a mammalian cell culture system utilizing Chinese hamster V79 cells, 3-HO-B(a)P (8 microM) inhibited the mutagenicity of B(a)P 7,8-diol-9,10-epoxide-2 (0.2 microM) by 50%. Although 3-HO-B(a)P was a potent inhibitor of the mutagenic activity of bay-region diol epoxides of benzo(a)pyrene, dibenzo(a,h)pyrene, and dibenzo(a,i)pyrene in S. typhimurium strain TA 100, higher concentrations of 3-HO-B(a)P were needed to inhibit the mutagenicity of the chemically less reactive benzo(a)pyrene 4,5-oxide and the bay-region diol epoxides of benz(a)anthracene, chrysene, and benzo(c)phenanthrene. Both 3-HO-B(a)P and 10-HO-B(a)P accelerated the disappearance of B(a)P 7,8-diol-9,10-epoxide-2 from 1:9 dioxane-water solutions at pH 7 and 25 degrees C. 3-HO-B(a)P, the most effective antimutagen of the B(a)P phenols tested, was much more reactive with the diol epoxide than 10-HO-B(a)P, the least effective antimutagen. The rate constant for the reaction of 3-HO-B(a)P with the diol epoxide exhibited a nonlinear (greater than first-order) dependence on the concentration of the phenol. Evidence was obtained for covalent adduct formation between the diol epoxide and each of the two phenols.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Background  

Restraint stress has been shown to elicit numerous effects on hippocampal function and neuronal morphology, as well as to induce dendritic remodeling in the prefrontal cortex (PFC). However, the effects of acute restraint stress on PFC cognitive function have not been investigated, despite substantial evidence that the PFC malfunctions in many stress-related disorders.  相似文献   
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