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241.
Over the past 20 years the taking of anabolic steroids by healthy athletes for the purpose of increasing body weight and strength has become very widespread. The ability of these agents to cause potentially serious side effects is discussed. In a series of 20 subjects studied over 18 months, no side effects of significance were recorded, and marked increases in strength and body weight were achieved.  相似文献   
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The response of a TLD-600/TLD-700 area dosemeter has been characterized in neutron fields around the 590 MeV cyclotron ring at the Paul Scherrer Institute (PSI). The dosemeter is based on a cylindrical paraffin moderator with three of each type of TLD chip at the centre, and is intended to use for area monitoring around accelerator facilities. The dosemeter is calibrated in terms of ambient dose equivalent using a non-moderated 252Cf neutron source. The ambient dose equivalent response has been tested in five locations where the neutron fields and dose rates have been well characterized by Bonner sphere spectrometer and active neutron monitor measurements. The different spectrum shapes and dose rates in the five locations permit the comparison of the behavior of the active and passive dosemeters in these neutron fields.  相似文献   
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A prospective study was performed to determine the incidence of group B streptococci cultured from the cervix in a series of obstetric clinic patients at St. Margaret's Hospital. Cultures were taken during each trimester and planted to both a blood agar plate and a selective broth medium. Of a total of 812 cultures, 18 were positive, an over-all incidence of 2.2 per cent. During the first, second, and third trimesters, 2.2 per cent, 2.5 per cent, and 1.9 per cent of cultures were positive, respectively. Women with positive cultures were treated with a 10 day course of oral penicillin or a suitable alternative; four of 16 had persistent positive cultures at the end of the first treatment period, three of these four responded to a second course of antibiotics, and the remaining patient responded after a third treatment course. The total number of positive cultures by selective broth was 24, compared to nine in blood agar, indicating a 2.7-fold increase in pickup by the selective broth.  相似文献   
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Affinity chromatography on agmatine-Sepharose was used for the separation of two active forms of urokinase (EC 3.4.99.26) from partially purified human urinary urokinase. The approximate molecular weight of the heavier form was 47 000 and of the lighter 33 400. Both forms were homogeneous by sodium dodecyl sulfate gel electrophoresis and by 3H-labeled diisopropylphosphorofluoridate and 14C-labeled p-nitrophenyl-p'-guanidinobenzoate incorporation studies. The 33 400 mol. wt. form had a single chain, and the 47 000 mol. wt. form had two chains (33 100 and 18 600 mol. wt.) linked by disulfide bonds. The specific activity of the heavier form was 104 000 CTA units/mg protein, compared with 226 000 units/mg for the lighter form but the activities per mmol of active site (molar activities) of the two forms were almost identical (9.6-10(9) and 10.2-10(9) CTA units/mmol). Isoelectric focusing on gels showed that the 47 000 material contained one major subform with a pI of 8.60 and a minor subform with a pI of 8.90, while the 33 400 material had three major subforms with pI values of 8.35, 8.60 and 8.70, respectively, and a minor subform with a pI of 8.05. 3H-labeled diisopropylphosphorofluoridate incorporation studies revealed an active-site serine residue in the heavy chain.  相似文献   
246.
Proposed to (a) replicate earlier findings that human Ss could voluntarily control peripheral skin temperature, (b) test the hypothesis that hypnotic susceptibility and the capacity for absorbed, imaginative attention would enhance autonomic learning and performance, and (c) demonstrate a learning effect, if one exists. A comparison was made with 7 Ss who scored high and 7 Ss who scored low on both a modified version of the Harvard Group Scale of Hypnotic Susceptibility and the Tellegen Absorption Scale. Auditory feedback was used to train Ss to produce a difference in skin temperature in one hand relative to the other in a direction specified by the E. Large and reliable performance and learning effects were found, but they were unrelated to hypnotic susceptibility or the capacity for absorbed, imaginative attention. Variables that might account for individual differences in learning and performance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Electrodeposited nickel-cobalt (EDNiCo) alloys ranging from 22 to 50% cobalt were produced and tested for strength as a function of thermal treatment and cobalt content. The electrolytes used were nickel and cobalt sulfamates with a total metal content of 75 g 1?1. Cobalt content was varied from 6 to 11% in the electrolyte. Cobalt was supplied by continuously metering in cobalt sulfamate solution. All alloys with cobalt content between 22 and 50% demonstrated yield strengths greater than 60 hbar in both the as-deposited condition and after stress relief at 345°C for 1 h. Highest as-deposited strength was exhibited by the EDNi43Co at 166 hbar (245 × 103 lb in?2) ultimate tensile strength and 117 hbar (170 × 103 lb in?) yield strength. The EDNi50Co was slightly lower at 161 hbar ultimate tensile strength. Stress relief of the EDNi43Co alloy at 455°C produced a strong material with very good ductility (elongation 25%, reduction of area 50%). A similar treatment of the EDNi50Co at 455°C resulted in a strength about 50% greater than that of EDNi in a hydrogen environment.  相似文献   
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