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881.
882.
B. Crymble 《BMJ (Clinical research ed.)》1968,3(5616):470-471
The carpal tunnel syndrome can cause severe pain and disability, both of which are avoidable if the condition is diagnosed and treated early in its course. Two sets of circumstances—delay in the correct diagnosis and recurrence of symptoms after an apparently successful operation—may give rise to problems in these aspects of management and delay recovery. 相似文献
883.
884.
885.
A simplified method of manual calculation for inbreeding coefficient (and/or relationship) from complicated pedigree tables presented in a nongraphic mode is offered. The method is based on the use of positional dual codes of ancestors in which all genealogical links of the proband are reflected. 相似文献
886.
Effect of estradiol-filled polydimethylsiloxane subdermal implants in adult male rats on the reproductive system, fertility, and progeny outcome 总被引:1,自引:0,他引:1
Combinations of testosterone and estradiol have been proposed as potential male contraceptives. For any compound to be an acceptable male contraceptive, it must be demonstrated either to prevent pregnancy completely or, if contraceptive failure occurs, to not have any adverse effect on pregnancy outcome. We have previously established that increasing doses of testosterone given via subdermal implants to adult male rats will decrease spermatogenesis and fertility but will not result in an increased incidence of pre- or postimplantation loss or in abnormal progeny. In the present study, we have monitored the effects of a dose of estradiol that has been proposed for the contraceptive regimen, as well as doses three and seven times as large, on progeny outcome. Adult male Sprague-Dawley rats received s.c. implants of estradiol-filled polydimethylsiloxane capsules of varying lengths and, after three months, were each mated twice to two females in proestrus. The smallest dose of estradiol (the dose used in the contraceptive formulation) did not have any significant effects on any of the measured parameters of the male reproductive system, or on the incidence of pre- or postimplantation loss or on progeny outcome. With increasing doses of estradiol, there was a marked reduction in fertility. This reduction in fertility was not associated with a sufficient decrease in epididymal sperm reserves to account for the decrease in number of females impregnated, but was associated with a major reduction in seminal plugs; this would suggest that the large doses of estradiol were decreasing male sexual behavior.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
887.
888.
V. S. Kurbanismailov O. A. Omarov G. B. Ragimkhanov M. Kh. Gadzhiev M. G. Bairkhanova A. J. Kattaa 《Plasma Physics Reports》2011,37(13):1166-1172
The experimental results on the formation and development of initial stages of an impulse breakdown in atmospheric-pressure
argon at townsend and streamer breakdown mechanisms for different initial conditions are presented. A streamer channel is
shown to be initiated by bright luminescence formed at the point of critical avalanche amplification at different distances
from the cathode depending on overvoltage. Prebreakdown currents are experimentally measured for the townsend and streamer
breakdown mechanisms and peculiarities of spark channel formation for these mechanisms are studied. 相似文献
889.
Merkel cell tumor: diagnosis, prognosis, and management 总被引:2,自引:0,他引:2
The histologic features of the Merkel cell and the pathologic characteristics of the Merkel cell tumor are described. From a literature review, 68 cases are examined; 23 cases that have been followed up accurately are presented from the Mayo Clinic. A representative case is used to demonstrate the problems of diagnosis and suggested treatment. The latter should be wide local resection with removal of nodal metastases if present. When indicated, this should be followed up with radiation therapy. Chemotherapy is of little or no value. Survival rates are presented. 相似文献
890.
R M Dixon B T Golding S Mwesigye-Kibende D N Ramakrishna Rao 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1985,311(1152):531-544
The vitamin B12 coenzyme adenosylcobalamin assists the enzymic catalysis of molecular rearrangements of the type (formula; see text) in which the migrating group X can be OH, NH2 or a suitable substituted carbon atom such as C(=CH2)CO2H. This paper discusses evidence for the participation of organic radicals as intermediates in these reactions. Theoretical and model studies supporting the intermediacy of radicals in the reactions catalysed by the enzymes diol dehydratase and alpha-methyleneglutarate mutase are described. For the model studies, alkyl radicals, alkylcobaloximes (alkyl represents, for example, ethoxycarbonyl substituted, but-3-enyl and cyclopropylmethyl) and also dihydroxyalkylcobalamins have been investigated. The Co-C alpha-C beta angle of 125 degrees in adenosylcobalamin is shown to be an 'especial' angle by analysis of the crystal structures of R- and S-2,3-dihydroxypropylcobalamin. 相似文献