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71.
T.‐F. WANG S. W. HORSLEY K.‐F. LEE S.‐C. CHU C.‐C. LI R.‐H. KAO 《International journal of laboratory hematology》2006,28(3):160-163
Cytogenetic abnormalities are observed in approximately two‐thirds of patients with acute myeloid leukemia (AML). Chromosome rearrangements are associated with specific subtypes of AML and associated prognosis. We report a patient with AML, M2, who was primarily refractory to standard induction chemotherapy with idarubicin and cytarabine. Flow cytometry of a bone marrow aspirate showed aberrant expression of B‐cell markers including CD19. Cytogenetic studies disclosed a translocation between 5q35 and 11q13. Fluorescence in situ hybridization analyses demonstrated that neither the NSD1 nor MLL genes were involved in this case. Further study is required to define conclusively the genes involved and their contribution to pathogenesis in this case. 相似文献
72.
The use of endogenous Protoporphyrin IX generated through the heme biosynthetic pathway after administration of 5-aminolevulinic acid (ALA) has led to many applications in photodynamic therapy (PDT). In Buenos Aires, Argentina, the Centro de Investigaciones sobre Porfirinas y Porfirias (CIPYP), reported for the first time, in 1975, porphyrin synthesis from ALA in highly dividing plant tissues. Increased porphyrin synthesis in tumours as well as cell photosensitisation was reported soon after. Our group is also interested in studying the use of new synthetic lipophilic derivatives of ALA as well as ALA delivery in liposomes. We have elucidated the mechanism of ALA transport in mammalian and yeast cells. The interactions between ALA-PDT and nitric oxide were investigated in three murine adenocarcinoma cell lines. In the National University of Río Cuarto, Córdoba, a group is devoted to the synthesis of new porphyrin-derived photosensitisers to study their effects on photoinactivation of bacterial and mammalian cells death by PDT. At the Centre of Electron Microscopy of the Cordoba National University, a prototype of a 630 nm noncoherent light source was designed and constructed. Cost of the light source and scarce knowledge of the benefits of PDT by physicians limit the spread of the treatment throughout the country. 相似文献
73.
TRAIL/死亡受体5途径在缺氧再给氧诱导人肝细胞凋亡中的作用及相关机制 总被引:3,自引:0,他引:3
目的:研究肿瘤坏死因子相关凋亡诱导配体(TNF-related apoptosis-inducing ligand,TRAIL)/死亡受体5(Death receptor 5,DR5)途径在人肝细胞缺氧/再给氧(Hypoxia/reoxygenation,H/R)损伤中的作用,并探讨其作用机制。方法:在体外建立肝细胞H/R模型,模拟肝脏的缺血再灌注。H/R处理后,培养基中加入不同浓度外源性TRAIL蛋白,噻唑盐比色法(MTT)和流式细胞术检测细胞活力和凋亡率。半定量RT-PCR检测DR5mRNA的表达。结果:以正常人肝细胞为对照,H/R使人肝细胞的DR5 mRNA的表达上调,再给氧2小时达峰值,此后直至再给氧20小时维持在相对高的水平。单纯缺氧6小时不能引起肝细胞的大量凋亡。TRAIL诱导H/R处理后的肝细胞发生凋亡,并呈浓度依赖性。H/R大大增强TRAIL的肝毒性。结论:H/R使DR5在人肝细胞的表达上调,增加TRAIL的肝毒性。TRAIL/DR5途径可能在IRI诱导人肝细胞凋亡过程中发挥重要作用。 相似文献
74.
Anne S Hinckers Manfred Laucht Martin H Schmidt Karl F Mann Gunter Schumann Marc A Schuckit Andreas Heinz 《Neuropsychopharmacology》2006,60(3):282-287
BACKGROUND: A low level of response to alcohol has been associated with both the genetic constitution of the regulatory region (SLC6A4) of the human serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) and with future alcohol intake and an increased risk for alcoholism. To date, all studies of relevant polymorphisms have been carried out in populations in the United States. METHODS: Data were extracted from a subset (n = 243) of a cohort of children who have been observed since birth through evaluation of the family history of alcoholism and psychosocial risk influences. At age 16 years, the response to alcohol was assessed with the Self-Rating of the Effects of Alcohol (SRE) questionnaire, and the average amount of alcohol intake per month was assessed during the prior 6 months. Additional variables that were measured included the 5-HTT genotype, externalizing behavior, and sociodemographic variables, such as gender and age. RESULTS: The level of response to alcohol was significantly lower among carriers of two long alleles of the 5-HTT regulatory region compared with carriers of one or two short alleles (Mann-Whitney U = 5225.0, p = .005). In a multiple regression analysis, the level of response to alcohol and externalizing behavior but not psychosocial factors significantly predicted the average amount of alcohol intake per month. CONCLUSIONS: This study demonstrates that, independent of the assessed psychosocial variables, the 5-HTT genotype correlated with the level of response to alcohol and predicted alcohol intake among 16-year-old adolescents. 相似文献
75.
The long-term cost of effective management for benign prostatic hyperplasia (BPH) remains an important issue in pharmacoeconomics because about 25% of men aged 50 yr and older experience voiding problems due to BPH. With the ageing population and the increase in the percentage of patients with BPH for whom any type of treatment can be considered, a substantial increase in total costs to society can be expected. The up-front costs of interventional approaches to BPH are being replaced by a pattern of long-term medical and preventive therapy. The age-adjusted rate of transurethral resection of the prostate (TURP) reached a high point in 1987 and TURP rates, but not costs, have been in decline ever since. Mean 1-yr treatment costs (medical therapy and TURP) have been estimated in a pan-European study to be 858 Euros per patient, 75% of which were medication costs. Using a 2-yr time frame for treatment, Medicare costs for finasteride, terazosin, and TURP have been estimated as $3874, $2161, and $1820, respectively. The available models of the total long-term cost for all therapies for BPH remain compromised by a lack of inclusion of indirect costs, the lack of true long-term data and, critically, the lack of human cost information (patient preference). Only medical therapy provides a preventive as well as symptomatic potential and, if all of the issues were fully incorporated, it is likely that medical therapy would be increasingly recognised as economically preferable. 相似文献
76.
IIEF-5与NEVA检测在阴茎勃起功能障碍诊断中的意义 总被引:2,自引:2,他引:0
目的探讨应用国际勃起功能评分5(IIEF-5)问卷表结合夜间阴茎勃起测定系统(NEVA)筛选勃起功能障碍(ED)的可行性及意义。方法148例门诊ED病人,应用IIEF-5问卷表评分,再通过NEVA测定仪监测夜间阴茎勃起情况,次日数据输入主机回放并分析。结果93例为心理性ED;在19~69岁的5个年龄组中,重度ED的比例由11.8%到55.0%,NEVA中度异常者IIEF积分(12.98±2.58)分,NEVA重度异常者IIEF积分(7.32±1.04)分。结论NEVA能有效地鉴别心理性与器质性ED,IIEF-5评分值与NEVA检测阴茎勃起时血容量变化值有相关性。IIEF-5与NEVA检测结合,能提高诊断和评估ED的可靠性。 相似文献
77.
鸡抗内毒素卵黄抗体IgY的制备 总被引:2,自引:1,他引:1
目的:研究分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌突变株15免疫鸡后其蛋黄中抗内毒素抗体IgY的产量、纯度、效价并筛选最佳免疫抗原。方法:分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌J5突变株作为抗原免疫25周龄Leghom鸡,水溶法(WD)提取蛋黄中抗体IgY,双紫外光测定抗体含量,SDS-PSGE电泳检测抗体纯度,细胞酶联染色和ELISA检测抗体特异性、效价及筛选最佳免疫抗原。结果:3种抗内毒素IgY含量和效价分别为14.4mg/ml和1:12 800(J5)、10.61mg/ml和1:12 800(LPS)、9.26mg/ml和1:3200(LipidA),抗体纯度均为95%左右。结论:大肠杆菌突变株J5和内毒素(LPS)为最佳免疫抗原,免疫鸡后其蛋黄中抗内毒素抗体IgY的产量和效价最高。 相似文献
78.
J. Kralovanszky N. Prajda S. Kerpel-Fronius T. Bagrij E. Kiss G. J. Peters 《Cancer chemotherapy and pharmacology》1993,32(3):243-248
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa. 相似文献
79.
B. A. Johnson Donald R. Jasinski Gantt P. Galloway Henry Kranzler Robert Weinreib Raymond F. Anton Barbara J. Mason Michael J. Bohn Helen M. Pettinati Richard Rawson Christopher Clyde 《Psychopharmacology》1996,128(2):206-215
Four hundred and twenty-three alcohol dependent subjects were enrolled into a 12-week randomized, double-blind, placebo-controlled
study to determine the safety and efficacy of the 5-HT2 receptor antagonist, ritanserin (2.5 mg/day or 5 mg/day), in reducing alcohol intake and craving. All subjects received 1
week of single-blind placebo prior to randomization into the 11-week double-blind phase. Additionally, all subjects received
weekly individual sessions of manual-guided cognitive-behavioral therapy. Comparing the single-blind period with endpoint,
there was approximately a 23% reduction in drinks/day; 34% fall in the total number of drinking days/week; 22% decrease in
drinks/drinking day; and a 37% diminution in alcohol craving for all treatment groups. All treatment groups experienced a
beneficial clinical outcome as assessed by the Clinical Global Impression Scale. There was, however, no significant difference
between treatment groups on any of these measures of alcohol drinking, craving, or clinical outcome. Subjects were of relatively
high social functioning at baseline, and this did not change significantly during treatment. Treatment groups did not differ
significantly on either medication compliance or reported adverse events. Ritanserin treatment was associated with a dose-related
prolongation of subjects’ QTc interval recording on the electrocardiogram. These results suggest that alcohol dependent subjects
can show marked clinical improvement within a structured alcohol treatment program. These findings do not support an important
role for ritanserin in the treatment of alcohol dependence.
Received: 30 April 1996/Final version: 3 July 1996 相似文献
80.
报道新化合物A-失碳-17β-羟基-17α-乙炔基-Δ3(5),9(10)-雌甾二烯-2-酮2的合成。文中探讨了用炔钾粗品对A-失碳-Δ3(5),9(10)-雌甾二烯-2,17-二酮1和A-失碳-6β,19-环氧-Δ3-雄甾-2,17-二酮3的选择性炔化,分别得标题化合物2(44%)及A-失碳-17β-羟基-17α-乙炔基-6β,19-环氧-Δ3雄甾-2-酮4(65%),4经还原性破开环氧、去羟甲基和去醋酰氧基合成了标题化合物2。四步总收率为34%。 相似文献