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31.
Cerebrospinal fluid samples from controls and patients with multiple sclerosis (MS) were split and sent to laboratories with different experiences for the detection of Chlamydia pneumoniae by polymerase chain reaction. Vanderbilt investigators identified C. pneumoniae in the majority of patients with MS and uncommonly in controls. Laboratories at Johns Hopkins University, University of Ume?, and the Centers for Disease Control and Prevention did not identify C. pneumoniae in any of the samples. Conflicting reports of C. pneumoniae detection in the some samples from patents with MS highlight the need to exchange detection techniques among laboratories involved in this controversy.  相似文献   
32.
In 30 survivors of childhood cancer, long-term psychological coping with experience of disease and treatment was studied in relation to factors associated with illness, treatment and demographic background. Coping was assessed in a prior study, in which three groups of varying levels of coping where delineated (good, 40%; intermediate, 33%; poor, 27%, coping). The present study showed that poor individual coping was related to diagnosis, a shorter time of continuous complete remission, more severe illness and treatment impairments, and lower scores on a test of intellectual abilities. In addition, a longer time of treatment tended to be followed by poorer coping. However, no association was found for gender, parents' occupational level, age at illness onset, neuro-cranial irradiation, irradiation dose (total) or age at investigation. A tentative path-analysis was executed, displaying a model for the relationships between medical and demographic background variables, and for their influence on coping. It was concluded that a complex of factors--associated particularly with severity of disease and treatment--appears to be related to, and affects, coping with the illness experience. Patients' long-term coping with their illness trauma is most likely determined by multiple factors. Intellectual capabilities are related to coping.  相似文献   
33.
A sample of 100 consecutive febrile neutropenic episodes in cancer patients in Kuwait was studied. Acute leukaemias (44%) and lymphomas (29%) were the most frequent underlying cancers; 21 bacteraemias (gram-positive 10, gram-negative 9, polymicrobial 2) were encountered. Staphylococcous epidermidis and Escherichia coli were the commonest organisms. Urinary tract infection occurred in 30% of the microbiologically documented cases. A total of 84 episodes responded to therapy and 9 of the 14 deaths were secondary to infection.  相似文献   
34.
Summary Single oral doses of rifampicin (10 mg/kg body weight), p-aminosalicylic acid (0.2 g/kg), isoniazid (10 mg/kg), or rifampicin and either p-aminosalicylic acid or isoniazid, were given to 69 tuberculous patients with normal renal and hepatic function. Ten-fold interindividual differences were observed in the peak serum concentrations and half-lives of rifampicin; its half-life was reduced from 4.3 h after the first dose to 3.1 h after the third dose, possibly due to self-induction of its own metabolism. No effect on its serum concentration or half-life, nor on those of isoniazid, were found after simultaneous oral administration of the two drugs. After treatment with rifampicin and p-aminosalicylic acid, the peak serum level of the former was delayed from 2 to 4 h, it was reduced from 8.0 to 3.8 µg/ml, and the mean area under the serum concentration curve throughout the entire 8 h study period was also lowered by about half. Individual patients did not attain therapeutically effective peak serum concentrations of rifampicin if also treated withp-aminosalicylic acid. The interaction observed between the two drugs is probably due to impaired gastrointestinal absorption of rifampicin, either by alteration of its physico-chemical properties or by a decrease in the gastric emptying rate combined with more rapid intestinal transit. The combination of these two drugs is unsuitable for the routine chemotherapy of tuberculosis.  相似文献   
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36.
Radiation therapy treatment planning is based on the calculation of the absorbed dose in the patient domain. For exact dose calculations, the solution of three coupled Boltzmann transport equations (BTEs) is needed to cover the transport of photons, electrons and positrons. In many situations, however, two coupled systems for photons and electrons are enough. The use of numerical methods in finding the exact solution of the unknown particle fluxes is necessary. In the stationary case, the BTE has six variables, three spatial, two directional and one energy variable. In this paper, we describe an approach in which the finite element method (FEM) is used to solve the six-dimensional problem. For the coupled photon-electron system, the variational formulation and the existence and uniqueness of the solution are derived. We simulate the solution of two coupled BTEs describing the travelling of photons and electrons in two spatial dimensions. The results are compared to Monte Carlo calculations with good agreement.  相似文献   
37.
PURPOSE: To evaluate the long-term social effect of illness and its treatment on young-adult survivors of pediatric cancer by addressing a selection of general social adjustment criteria. METHODS: In a cross-sectional case-control study, 30 young-adult survivors of childhood cancer were compared with (1). controls with no history of serious illness, matched by sex, age, and geographic area of residence, and (2). general population norms on the subject of educational and vocational factors, habitation, family/partner relationships, parenthood, and leisure activities. RESULTS: The educational status of survivors was similar to that of controls, although a smaller proportion of the patients expressed concrete plans for future vocational or educational advancement. Survivors had less frequently entered higher education compared with general population norms. A longer duration of treatment was related to a lower estimated socioeconomic level, and poor psychological coping with the illness experience was associated with the fact that they were still living with their parents, a shorter education, and a lower socioeconomic level. CONCLUSIONS: The social, vocational, and educational adjustment of relapse-free survivors from childhood cancer appears as only moderately, if at all, negatively affected by the illness and treatment history. However, the treatment intensity and particularly the survivors' coping with their illness experience may influence their ability to achieve long-term social goals. These findings suggest that special attention should be given to matters concerning education and partner relationships at long-term follow-up of pediatric cancer patients.  相似文献   
38.
'Orujo' olive oil is obtained by chemical processes from the waste resulting from the mechanical extraction of virgin olive oil. The aim of the present study was to evaluate a new pharmacological property of two natural triterpenoids contained in olive oil, as vasodilatory agents, and to determine their mechanism of action. The two compounds studied were oleanolic acid and erythrodiol. The vasorelaxant effect induced by these pentacyclic triterpenoids was studied in isolated thoracic rat aorta. Oleanolic acid and erythrodiol, accumulatively added, showed vasorelaxant activities in aortic rings with endothelium pre-contracted by 10(-6) m-phenylephrine (maximum percentage of relaxation 86.38 (sem 2.89) and 73.53 (sem 6.01), respectively). They had almost no relaxant effect on depolarised or endothelium-denuded aortic segments. The relaxation was significantly attenuated by pre-treatment with the NO synthase inhibitor N(omega)-nitro-L-arginine-methylester (L-NAME; 3x10(-4) m). To characterise the involvement of endothelial factors, in addition to NO, arteries with endothelium were exposed to 10(-5) m-indomethacin (INDO), a cyclo-oxygenase inhibitor, or INDO plus L-NAME. INDO did not have any significant effect on the relaxant response of both compounds. The combination of L-NAME plus INDO only abolished the oleanolic acid-induced relaxation. The present results suggest that the mechanism of relaxation seems to be mainly mediated by the endothelial production of NO; however, other mechanisms cannot be excluded. It can be concluded that oleanolic acid and erythrodiol may have interesting therapeutic potential as new vasodilator drugs, thus protecting the cardiovascular system. Therefore, the intake of 'orujo' olive oil, as a source of these compounds, might be beneficial in this regard.  相似文献   
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40.
Lungs from skin-sensitised and non-sensitised guinea pigs were exposed via the airways to 3-carene (1900 mg/m3) and perfused with buffer containing either autologous plasma or lymphocytes. The experiments were performed in order to investigate the importance of blood components for the increased lung responsiveness seen in skin-sensitised animals. A reduction in lung function was noted in all lungs during 3-carene exposure. There was no difference in the 3-carene response between lungs from skin-sensitised animals versus lungs from non-sensitised animals when the perfusion buffer contained lymphocytes. However, when plasma diluted with buffer was used as perfusion medium, there was a significant enhancement in the response in lungs from sensitised versus lungs from non-sensitised animals. This implies that skin sensitisation increases lung responses to inhaled 3-carene and those components in plasma, and not the lymphocyte fraction, contributes to the observed increased lung responsiveness.  相似文献   
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