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81.
The atomic rearrangement cascade that follows the electron-capture decay process in low-Z radionuclides involves X-rays which have high photoelectric interaction probabilities. When the K-shell binding energy of the ionized atom (e.g., hydrogen) is significantly lower than the energy of the X-ray photon, the detector response to a photon-equivalent energy electron and the whole photoionization process are very similar. This is not the case when the scintillator cocktail contains larger atoms (e.g., oxygen and phosphorus in Ultima Gold). For larger Z atoms, the reduced energy of the whole photoionization process is less than the reduced energy of the interacting photon due to the nonlinear effects of ionization quenching. This paper shows the convenience of including a more detailed simulation of the photoionization process in the atomic rearrangement detection model for electron-capture nuclides such as (55)Fe, (51)Cr and (54)Mn. The need for more elaborate atomic rearrangement models is a consequence of the analysis of (125)I data. 相似文献
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U. Bolm-Audorff S. Brandenburg T. Brüning H. Dupuis R. Ellegast G. Elsner K. Franz H. Grasshoff V. Grosser L. Hanisch B. Hartmann E. Hartung K. G. Hering G. Heuchert M. Jäger J. Krämer Dr. A. Kranig E. Ludolph A. Luttmann A. Nienhaus W. Pieper K.-D. Pöhl T. Remé D. Riede G. Rompe K. Schäfer S. Schilling E. Schmitt F. Schröter A. Seidler M. Spallek M. Weber 《Trauma und Berufskrankheit》2005,7(3):211-252
Occupational diseases Nos. 2108 and 2110 correspond to intervertebral disc-related diseases of the lumbar spine from many years of carrying or lifting heavy loads, occupations in extreme postures of full flexion or oscillation of the whole body when seated, and which compel the cessation of all activities which are or could be the cause for the origin, exacerbation or recurrence of the disease. These occupational diseases came into force at the start of 1993, but there have been considerable problems in their implementation. The present Part I of the contribution is the result of the work of an interdisciplinary study group and contains medical criteria for the assessment of possibly strain-related clinical characteristics and the evaluation of other possible causes. Part II is to be published in Volume 4/2005 and will deal with questions related to forced cessation and to the assessment of the loss of earning ability. Agreement was reached in many areas related to the assessment of occupational claims. This should allow for evidence-based decision making in the future for the occupational diseases Nos. 2108 and 2110. 相似文献
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86.
Simultaneous angiographic late stent thrombosis in two different coronary vessels after withdrawal of the combined anti-platelet therapy 总被引:2,自引:2,他引:0
87.
Onur Hapa Hüsamettin ?ak?c? Kaan Gidero?lu Kutay ?zturan Aysel Kükner Güler Bu?dayc? 《Archives of orthopaedic and trauma surgery》2009,129(12):1721-1726
Introduction
Ethanol has a suppressive effect on inflammation and the immune system, but the effect of ethanol on tendon healing in vivo has not been studied. The purpose of this study was to investigate the histological and biomechanical effects of ethanol intake on tendon healing in a rat tendon injury model. 相似文献88.
89.
Fatih Arikan Ali Gürkan 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(4):452-457
OBJECTIVE: To introduce 1,1,1,2 tetrafluoroethane (TFE), as a new material for cryosurgery of gingival melanin pigmentation (GMP). STUDY DESIGN: Twenty-one patients with GMP were treated using a TFE-cooled cotton swab. Standard digital images of pigmented areas were measured preoperatively and postoperatively with image-analyzing software. The Mann-Whitney U test was used for statistical analysis. RESULTS: Keratinization was completed 3 to 4 weeks after application, without any trace of pigmentation. Statistical analysis revealed a significant difference between preoperative and postoperative measurements of pigmented areas (P < .05). During the follow-up period, no side effects were observed and improved esthetics were maintained up to month 30. CONCLUSIONS: The clinical outcomes of cryosurgery with TFE for treatment of GMP are very satisfactory. The use of TFE for cryosurgical treatment of GMP is practical and inexpensive. Moreover, unlike other cryosurgery methods no special equipment is required, and it is safe to store in the dental clinic. 相似文献
90.
Platelet Aggregation Inhibiting and Anticoagulant Effects of Oligoamines, VII: Benzene-1,3,5-trialkanamines Seventeen title compounds were synthesized. Platelet aggregation induced by collagen in vitro is inhibited by 9 of them at IC50 = 2–4 μmol/L. Seven compounds depress the formation of fibrin to ≦ 25 % of normal in concentrations below 50 μmol/L. Compound 15 [4-(2-thienylbutyl)benzene-1,3,5-trimethanamine is the first oligoamine which shows anticoagulant and antiplatelet effects at the same concentration (25 μmol/L). 相似文献