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951.
952.
The Medical Research Council UKALL V trial for children with standard-risk acute lymphoblastic leukemia (ALL) (aged 1 to 14 years, leucocyte count less than 20 X 10(9)/L) was designed to determine whether the immunosuppressive effects of treatment could be reduced without sacrifice of antileukemic effect by alterations in the type of continuing therapy or in fractionation of cranial irradiation. Remission was achieved in 496 children on standard induction therapy, and 309 children received 24 Gy of cranial irradiation in ten to 16 fractions over 21 days, and 174 received 21 Gy in five to nine fractions over 21 days. The type of radiotherapy administered had no influence on relapse at any site or rate of death in remission. All 496 children were randomized to receive chemotherapy for 2 or 3 years with 6-mercaptopurine and methotrexate either as a continuous (group C) or a semicontinuous (group G) regimen or as a five-day pulse every 3 weeks (group I). All groups also received vincristine and prednisolone every 6 weeks. With a minimum follow-up of almost 7 years, patients in group I had significantly fewer remission deaths (P = .025) but a much higher rate of bone marrow relapse than those in group C or G (P = .002). There was an overall benefit for 3 years of chemotherapy compared with 2 years, which in contrast to previous studies, was more apparent in girls and in patients in groups C and G. Testicular relapse occurred in 37 boys, including 19 patients off therapy, with a previously negative biopsy. The overall results confirmed the prognostic significance of initial leucocyte count, even among these standard-risk patients, while girls had a superior rate of disease-free survival, but not of hematologic remission. It is concluded that, even among standard-risk patients, the prognosis is influenced by the height of the initial leukocyte count. While alterations in the fractionation of cranial irradiation do not appear to have influenced disease-free survival, intermittent continuing chemotherapy, although less immunosuppressive, is less effective than conventional continuous therapy in the treatment of ALL. In this study, 3 years of chemotherapy appeared superior to 2 years.  相似文献   
953.
Secondary prevention of coronary events in coronary artery disease (CAD) patients with aspirin is generally accepted because of ease of administration, predictable safety, and proven efficacy. The use of long-term anticoagulant therapy with heparins, vitamin-K antagonists (VKAs), or thrombin inhibitors is, however, more controversial. During the last 40 years, several trials have been conducted in order to evaluate the role of anticoagulant therapy in patients with CAD as a protection against subsequent death and thrombo-embolic complications. The conducted trials are heterogeneous in many ways, concerning comparative medications, patient populations, endpoints and follow-up, which makes a standardized recommendation on the basis of these studies difficult. This review is an overview of the largest and best studies on this topic and discusses the scientific background for a possible use of VKA or an alternative anticoagulant treatment in CAD patients, looking at both the beneficial effects and the risk of bleeding.  相似文献   
954.
955.
Repetitive cyclic loading from daily activities is reported to induce fatigue damage and microcracking in bone structures. In terms of osteoporotic structures or in cases of serious damage of skeleton segments and the replacement by metallic implants the degree of damage due to cyclic loading will be even more pronounced. It is generally assumed that fatigue induced cracking and crack propagation essentially act as driving forces for complex physiological phenomena such as remodelling processes of bones and the adaptation to applied loads. In cases where the crack propagation rate exceeds the remodelling velocity, sudden and unexpected fracture of the bone is observed. Especially for implant reinforced structures the deviation in stiffness to the bone material can induce high peak stresses and accelerate crack propagation. Whereas, for cortical bone the mechanical behaviour under cyclic loading is sufficiently described, only rough data are available for trabaecular structures. In this study the deformation behaviour of bovine vertebra trabecular bone specimens is investigated under cyclic compressive loading. A powerlaw relationship was found between the applied load ratio and cycles to failure. A linear decrease of maximum, integral strains at failure with increasing applied load ratio was observed. Optical deformation measurement of the surface strains revealed that low strains (0-1 increasing applied load ratio whereby the higher strains behave directly opposite. This indicates that different failure mechanisms are acting at low cycle and high cycle fatigue, respectively.  相似文献   
956.
957.
The endotoxin receptor soluble CD14 (sCD14) has been implicated in the 'hygiene hypothesis' suggesting reduced allergic sensitization with bacterial stimulation. However, the relationship between early life sCD14 and allergic diseases is conflicting. We aimed to investigate whether possible risk factors for allergic diseases were associated with sCD14 levels at 2 yr of age. In the nested case-control study of the birth cohort studies 'Environment and Childhood Asthma study in Oslo' 411 children selected with recurrent bronchial obstruction (rBO) (n=241) and no bronchial obstruction (n=170) by 2 yr were investigated with skin prick test and structured parental interview at age 2 yr. Exposure to tobacco smoke, pets and infections was recorded semi-annually by questionnaires (0-2 yr). The sCD14 was analysed from frozen, stored serum by ELISA technique. Regression analyses were performed in all subjects with complete data (n=406, 180 girls), and in girls and in boys separately. Mean sCD14 (ng/ml) was significantly higher among girls 2035 (1973-2096) vs. 1947 (1890-2004) (boys). The sCD14 was significantly reduced among girls exposed to antenatal maternal smoking and with parental asthma, after adjusting for age, parental rhino-conjunctivitis, pet keeping and childhood infections. Recurrent otitis media (OM) increased and common colds significantly decreased sCD14 levels in girls. Boys with atopic dermatitis and rBO had reduced sCD14. Pet exposure was not significantly associated with sCD14. We report novel gender-related effects of sCD14 in early life and suggest that gender, tobacco smoke exposure, age and middle ear disease in particular should be accounted for when assessing the role of sCD14 in childhood allergic diseases.  相似文献   
958.
959.
The prospective case series study presented here was conducted to assess the outcome of patients with infections caused by polymyxin-only-susceptible (POS) gram-negative bacteria managed with intravenous colistin. Between July 2003 and April 2005 a total of 27 patients were infected with a POS gram-negative bacterium and received intravenous colistin at a dose of 2 million international units (MIU) (160 mg or 66.7 mg colistin base) every 8 h for a mean (±SD) duration of 13.9 (±7.5) days. Nine patients had ventilator-associated pneumonia and received, in addition to the intravenous colistin therapy, 1 MIU (80 mg or 33.3 mg colistin base) aerosolized colistin every 12 h for a mean (±SD) duration of 13 (±6.5) days. The predominant pathogens were Pseudomonas aeruginosa (n=17) and Acinetobacter baumannii (n=12); in two patients both pathogens were isolated from one clinical specimen. In-hospital mortality and clinical response were 15% and 85%, respectively. Colistin-associated nephrotoxicity was observed in two of the 27 patients. POS gram-negative pathogens represent a major threat for hospitalized patients. Colistin appears to be an effective and safe treatment, even in patients with severe underlying diseases.  相似文献   
960.
There have only been a few studies on the role of mineral intake in tooth loss. We investigated the association between mineral intake and the prevalence of tooth loss in Japan. We used the baseline data on 1002 pregnant women who were enrolled in the Osaka Maternal and Child Health Study between November 2001 and March 2003. Tooth loss was defined as the previous extraction of one or more teeth. Nutrient intake was assessed by a validated diet history questionnaire. Prevalence odds ratios and confidence intervals were estimated by applying a multiple logistic regression model. The adjusted odds ratio upon comparison of the highest quartile with the lowest quartile of magnesium intake was 0.64 (95% confidence interval, 0.42-0.99), showing a tendency for an inverse dose-response relationship (p for linear trend = 0.05). There were no associations between the level of consumption of calcium, phosphate, iron, zinc, or copper and tooth loss. The present findings suggest that intake of magnesium is related to reduced prevalence of tooth loss among young Japanese women.  相似文献   
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