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The postnatal development of alcohol dehydrogenase (ADH) isozymes was studied in liver, kidney, stomach and eye tissues of C57BL/6J inbred male mice using agarose isoelectric focusing and histochemical methods. Development profiles were tissue specific, with adult patterns being attained by 30 days in the liver and stomach, and by 42 days in the kidneys. Ocular ADH-C2 increased in activity at the end of the first week, corresponding to the time of eye opening in the neonate. 相似文献
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Intradural cavernomas are rare vascular lesions of the spinal cord. Four cases of histologically verified cavernomas of the cord are reported, of which two were extramedullary and two were intramedullary in location. Progressive neurological deficit was the presenting feature in three cases while one patient had a rapid evolution of neurological deficits and was found at surgery to have had bled from the extramedullary lesion. All the patients were subjected to surgery and total excision of the cavernomas was carried out in each case. While two patients improved after surgery the other two remained static. The available literature on spinal cord cavernomas is reviewed. 相似文献
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Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk
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Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer. 相似文献
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Peter J. Makin Usharani Rout Cary L. Cooper 《The British journal of general practice》1988,38(312):303-306
Questionnaires assessing levels of job satisfaction and possible sources of stress were distributed to a random sample of general practitioners in the Greater Manchester area. The highest levels of job satisfaction were reported for `intrinsic' job factors such as freedom to choose method of working, amount of responsibility and amount of variety, rather than `extrinsic' factors such as rate of pay and hours of work. The main causes of stress appeared to be interruptions of various kinds. Factor analysis revealed four major sources of stress: interruptions; emotional involvement; administrative workload and work/home interface; and routine medical work. Of these, all but routine medical work were associated with job satisfaction. It is concluded that the major sources of stress for the general practitioner are not medical, but social. 相似文献
9.
Baishnab C. Singh Basanta K. Misra Anuradha Rout Nigamananda Mallick M. K. Rout 《Macromolecular chemistry and physics.》1979,180(4):953-958
The kinetics and mechanism of the inhibiting action of toluene on the Ce(IV) initiated polymerization of acrylonitrile were studied together with the effects of [M], [Ce(IV)], [Toluene], [HClO4], [NaClO4], and [Acetic acid] on the rate of polymerization. The values of composite rate constant kkt/kpkoki for toluene (and substituted toluenes) was calculated by plotting [M]/Rp versus [M]?1. A very significant observation in the present study was that the plot of [M]/Rp versus [M]?1 gave a negative intercept, which seems to be a general observation for all inhibiting substrates. On the basis of the experimental data, it could be concluded that the benzyl radical obtained by hydrogen abstraction, and not a chain transfer, is responsible for the inhibition. 相似文献
10.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献