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41.
GM Ginsberg T Schlesinger A Ben-Shlomo A Kushilevsky M Margaliot M Oren M Finkleman A Friedman M Handlesman B Lev 《Canadian Metallurgical Quarterly》1998,71(844):406-412
In Israel the diffusion of rare earth screen technology has been limited. These screens could halve the radiation dose to the patient from diagnostic X-ray radiography, with little managerial effort and without being detrimental to the quality of the diagnostic image. We estimated the total effective dose from diagnostic film radiography capable of reduction by the use of rare earth screens, based on the number of hospital and ambulatory diagnostic X-ray procedures. This number was multiplied by the computed radiation dose per body site for a series of diagnostic procedures. The annual dose was approximately 0.53 mSv per head, approximately half of which could be averted by the introduction of rare earth screen technology. Based on a fatality risk of 3% Sv-1, it is estimated that the adoption of rare earth screen technology might reduce the annual incidence of cancer by some 93 cases, half of which would be fatal after an average latency period of 18.4 years. The cost of purchasing rare earth screens on a nationwide basis is approximately $3.0 million. This cost is outweighed by a saving of $9.6 million in X-ray tube replacement costs over the period 1997-2006. Government legislation enforcing the use of rare earth screens is essential, because of the lack of prestige associated with acquiring rare earth technology, as well as institutional reluctance to accept the external benefits of reduced morbidity and mortality and/or to extend budgetary time horizons. 相似文献
42.
OBJECTIVE: The objective of this study was to assess somatic and inherited androgen receptor gene mutations in families with only one affected individual. METHODS: Molecular genetic analysis of the androgen receptor gene in DNA derived from blood leukocytes from 30 families with single-strand conformation analysis, direct sequencing, and restriction fragment analysis was performed. RESULTS: In 22 families the mothers and all investigated grandmothers were heterozygous carriers. However, within the sisters and aunts, both heterozygous carriers and noncarriers were present. In eight families a de novo mutation was characterized. In three of these patients indication for somatic mosaicism was found. CONCLUSIONS: De novo mutations occur at a high rate within the androgen receptor gene (8 of 30 = 26.7%); a high proportion (3 of 8) arise after the zygote stage. Thus only direct analysis of the underlying mutation of the androgen receptor gene in the proband and his or her family can provide the basis for genetic counseling. 相似文献
43.
RL Richards M Rao NM Wassef GM Glenn SW Rothwell CR Alving 《Canadian Metallurgical Quarterly》1998,66(6):2859-2865
Encapsulation of soluble protein antigens in liposomes was previously shown to result in processing of antigen via the major histocompatibility complex class I pathway, as evidenced by costaining of the trans-Golgi region of murine bone marrow-derived macrophages (BMs) by fluorophore-labeled liposomal antigen and by a trans-Golgi-specific fluorescent lipid. Evidence is presented here that free or liposome-encapsulated RTS,S, a particulate malaria antigen consisting of hepatitis B particles coexpressed with epitopes from the Plasmodium falciparum circumsporozoite protein, also was localized in the trans-Golgi after incubation with BMs, suggesting processing by the class I pathway. An in vivo cytotoxic T-lymphocyte (CTL) response was detected, however, only after immunization with RTS,S encapsulated in liposomes containing lipid A and not after immunization with free RTS,S or with RTS,S encapsulated in liposomes lacking lipid A. Therefore, intracellular delivery of antigen containing CTL epitopes to the Golgi of BMs does not necessarily result in a CTL response in vivo unless an additional adjuvant, such as liposomes containing lipid A, is utilized. Encapsulation of RTS,S in liposomes containing monophosphoryl lipid A (MPL) resulted in a dose-dependent enhancement of the NANP-specific immunoglobulin G (IgG) antibody response compared to that of free RTS,S. The IgG1 and IgG2a subclasses predominated after immunization with RTS,S encapsulated in liposomes containing MPL. These results demonstrate that encapsulation of a lipid-containing particulate antigen, such as RTS, S, in liposomes containing lipid A can enhance both humoral and cellular immune responses. 相似文献
44.
A part of a larger study of the health behaviors of adolescent women, this investigation examined health-promoting behaviors and the influence of cognitive, social, and environmental factors on these health-promoting behaviors of rural adolescent women. The sample consisted of 128 rural African-American and white adolescent women. Forty-four percent of the variance in health-promoting behavior of this sample was explained by five variables: self-image, problem solving, mother's education, employment status, and family structure. Self-image was the most salient predictor of health-promoting behavior, explaining 33% of the variance. 相似文献
45.
GM Ribbers WP Oosterhuis J van Limbeek M de Metz 《Canadian Metallurgical Quarterly》1998,79(12):1549-1552
OBJECTIVE: Evaluation of immune system function in patients with reflex sympathetic dystrophy (RSD). DESIGN: Survey on blood samples obtained from RSD patients and from a randomly selected control group. The lymphocyte populations (T, B, NK cells), and the activated T cells (CD25, and HLA-Dr-positive CD4 and CD8 cells) were analyzed by flow cytometry with dual-color direct immunofluorescence after whole-blood lysis. Clinical chemistry parameters were analyzed in additional serum samples. SETTING: Tertiary care center (outpatient rehabilitation clinic). SUBJECTS: Thirteen patients (nine women) with RSD and a control group of 21 healthy individuals. MAIN OUTCOME MEASURES: The results of the flow cytometry analysis of RSD patients were related to those of the control subjects. Means were analyzed, and confidence intervals for differences of the means were calculated. The means of the clinical chemical analysis were related to local reference values. RESULTS: The flow cytometry analysis did not differ between RSD patients and healthy controls. Although in some patients an individual parameter of clinical chemical analysis differed from its reference value, all of the mean values were within reference limits. Stratification on medications with immunomodulatory effects and on probability of a definite diagnosis of RSD had no influence on the results. CONCLUSION: No association between immunologic indices and RSD was found. This finding is relevant, because recent theories stress that it is not the sympathetic nervous system but a local inflammatory reaction that is fundamental in the pathogenesis of RSD. The results of this study do not support this theory. 相似文献
46.
AS Stein MR O'Donnell A Chai GM Schmidt A Nademanee PM Parker EP Smith DS Snyder A Molina DE Stepan R Spielberger G Somlo KA Margolin N Vora J Lipsett J Lee J Niland SJ Forman 《Canadian Metallurgical Quarterly》1996,14(8):2206-2216
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT. 相似文献
47.
V Mollace M Colasanti C Muscoli GM Lauro M Iannone D Rotiroti G Nistico 《Canadian Metallurgical Quarterly》1998,124(4):742-746
Articles in this issue by A. C. Casiglia, A. LoCoco, and C. Zappulla; D. S. Crystal, H. Watanabe, K. Weinfurt, and C. Wu; M. Keller, N. Edelstein, C. Schmid, F. Fang, and G. Fang; and J. J. Han, M. D. Leichtman, and Q. Wang are discussed according to (a) the extent to which cultural variability can be reconciled with developmental theory and (b) the dimensions of cultural variability that matter most for development. It is argued that (a) cross-cultural research needs to be predicted on a model of how culture interacts with the forces that underlie and guide development and (b) the interpretation of cross-cultural research is severely limited without the direct measurement of the specific culture-related variables and processes that are hypothesized to account for diversity in development. Finally, within-culture variability needs to be studied in conjunction with between-culture variability so that a full model of diversity and development can be constructed. 相似文献
48.
49.
Erwin W. Karg George A. Ferron Stefanie Bauer Sebastiano Di Bucchianico Ralf Zimmermann 《Aerosol science and technology》2020,54(6):668-684
AbstractCell exposure experiments at the air-liquid interface (ALI) are used increasingly as indicators for health effects and for the impact of aerosols on the lung. Thereby the aerosol particles are kept airborne and can deposit on a cell surface area similar to the human respiratory tract (RT). However, geometry and air flow rates of an ALI system deviate considerably from the RT. As the tissue-delivered particle dose to the lungs (TD) can hardly be measured, computer models of particle deposition are used here to mimic both the particle deposition at ALI and in the RT. An ALI exposure setup (VitroCell GmbH) for an airflow rate of 100 cm3 min?1 is selected, where the particle deposition model has been verified experimentally. For the RT we use the hygroscopic lung deposition model of Ferron et al. (2013). Model runs are performed for the particle deposition and for the deposited particles per surface area in both the ALI and the RT. The results show that the ALI-deposited mass is 1-2 orders of magnitude higher than in the alveolar region, because the surface area of the lung region is substantially larger. A particle size range from 40 to 450 nm is identified, where the ratio of both the deposition in a lung region and the deposition at the ALI varies by a factor less than two. Mean values for this ratio are 31 and 101 for the tracheo-bronchial and the alveolar region, respectively. The same size range is found for the ratio of the deposited particles per surface area in a lung region and at the ALI. For this range the mean surface deposition at the ALI is 23- and 1575-times larger than in the tracheo-bronchial and the alveolar lung region, respectively. The effect is partly compensated by different flow rate and cell size.Copyright © 2020 American Association for Aerosol Research 相似文献
50.
The male-to-female ratio of patients requiring dialysis treatment commonly approaches 2:1. It is proposed that environmental factors, particularly occupational exposure to hydrocarbons, may account for the excess number of male patients. The term "hydrocarbon" refers to the aliphatic, alicyclic, aromatic, and halogenated hydrocarbons (carbon tetrachloride, chloroform); glycols (ethylene glycol, diethylene glycol, dioxane, glycerol); and organic solvents. Hydrocarbons commonly find use as solvents in industrial manufacturing practices because of their lipid solubility. Hydrocarbons have long been known to be neurotoxicants, affecting both peripheral and central nervous systems. Although benzene and its derivative have a known association with uroepithelial tumors, there is now a considerable body of evidence suggesting a possible role for hydrocarbon exposure in the development of non-neoplastic renal diseases. This article presents an epidemiological case for such an association and critically reviews the literature. 相似文献