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101.
Narcolepsy and low CSF orexin (hypocretin) concentration after a diencephalic stroke. 总被引:4,自引:0,他引:4
Idiopathic narcolepsy usually results from a loss of the hypothalamic neuropeptide orexin (hypocretin), but the cause of secondary narcolepsy resulting from focal brain lesions is unknown. The authors describe a young man who developed narcolepsy after a large hypothalamic stroke. His lesion included much of the hypothalamic region in which orexin is produced, and his CSF concentration of orexin was low. The authors hypothesize that a loss of orexin neurons or their relevant targets may be the specific neuropathology causing this and many other cases of secondary narcolepsy. 相似文献
102.
Participation of older newly-diagnosed cancer patients in an observational prospective pilot study: an example of recruitment and retention 总被引:1,自引:0,他引:1
Martine TE Puts Johanne Monette Veronique Girre Christina Wolfson Michele Monette Gerald Batist Howard Bergman 《BMC cancer》2009,9(1):277-14
Background
There have been few prospective observational studies which recruited older newly-diagnosed cancer patients, and of these only some have reported information on the number needed to screen to recruit their study sample, and the number and reasons for refusal and drop-out. This paper reports on strategies to recruit older newly-diagnosed cancer patients prior to treatment into an observational prospective pilot study and to retain them during a six-month period. 相似文献103.
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105.
Lipid peroxidation and susceptibility of low-density lipoprotein to in vitro oxidation in hyperhomocysteinaemia 总被引:4,自引:0,他引:4
H. J. BLOM H. A. KLEINVELD† G. H. J. BOERS† P. N. M. DEMACKER† H. L. M. HAK-LEMMERS† M. T. W. B. TE POELE-POTHOFF J. M. F. TRIJBELS 《European journal of clinical investigation》1995,25(3):149-154
Abstract. The pathobiochemical mechanism of arteriosclerosis in hyperhomocysteinaemia has not yet been elucidated. In vitro studies have shown that the cytotoxic properties of homocysteine can be ascribed to its generation of reactive oxygen species. We studied lipid peroxidation, both in vivo and in vitro , in 10 homozygous cystathionine synthase-deficient (CSD) patients and in a control group of 10 healthy subjects of comparable age and sex. The susceptibility of low-density lipoprotein (LDL) from hyperhomo-cysteinaemic patients to oxidation was determined in vitro by continuously measuring the conjugated diene production induced by incubation with copper ions. Oxidation resistance (expressed as lag time), maximal oxidation rate, and extent of oxidation (expressed as total diene production) of LDL from CSD patients were not significantly different from those of LDL from controls. Furthermore, the time needed to reach maximal diene production, i.e. t(max), was similar for LDL from patients and controls. In addition, the vitamin E concentrations in LDL of CSD patients and controls were similar. The mean concentration (± SD) of plasma thiobarbituric acid reactive substances (TBARS), an indicator of in vivo lipid peroxidation, was 2.2 ± 0.7 μmol L-1 in CSD patients, a lower value than that measured in the matched controls (50± 2.0 μmol L-1 ). Investigation of in vivo and in vitro parameters of lipid peroxidation shows that the increased risk of arteriosclerosis in hyperhomocysteinaemia is unlikely to be due to increased lipid peroxidation. 相似文献
106.
Diaphragmatic rupture: CT findings in 11 patients 总被引:7,自引:0,他引:7
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109.
We investigated whether cigarette smoking, measured by follicular fluid
concentrations of cotinine (a major metabolite of nicotine), affects the
maturity of oocytes from women undergoing in-vitro fertilization (IVF) and
embryo transfer. In 234 women, follicular fluid samples were assessed for
cotinine and their 2020 oocytes were assessed for maturity stage. Data on
individual proportions of oocytes which were mature (OM) and were
fertilized (OF) were analysed by regression in relation to age and
follicular fluid cotinine. OF gave an independent assessment of oocyte
maturity. Both age and follicular fluid cotinine entered the OM and OF
regressions and were significant. The age-adjusted regression coefficients
for log cotinine were positive; greater cotinine concentrations usually
accompanied greater OM and OF. The cotinine effect on OM was positive in
younger women, but it became negative (decreased OM with increasing
cotinine concentrations) in older women (> or = 40 years). We further
found in older women an average reduction of approximately 50% in the
number of mature oocytes; this reduced number was lower than the number of
embryos usually transferred. Smoking can reduce the number of mature
oocytes even further, therefore risking a negative IVF-embryo transfer
outcome. This may be the reason why the negative effects of smoking become
clinically detectable in older women.
相似文献
110.
The rate of perineal wound healing was assessed in a series of 112 patients undergoing proctectomy for Crohn's colitis. Healing was impaired in patients with a high fistula-in-ano or a rectovaginal fistula pre-operatively, faecal contamination and postoperative perineal sepsis. Early healing (within 12 weeks) occurred in 63 per cent of the patients. Healing was delayed by over one year in 21 patients, and in 10 patients the perineal wounds never healed. 相似文献