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991.
From the genotyping of UK and US tylotic families with a high risk of oesophageal cancer we have previously localized the tylosis-associated cancer susceptibility gene (TOC gene, tylosis oesophageal cancer gene) to a 1 cM region on the long arm of chromosome 17 (Kelsell et al., 1996). In the present study we investigated loss of heterozygosity (LOH) patterns of 35 sporadic squamous cell carcinomas of the oesophagus using six polymorphic microsatellite markers encompassing this locus. Twenty-four of the 35 cases (69%) revealed LOH at one or more loci. Deletion was most frequently observed with the marker D17S801 (64% LOH, informative cases), which shows significant linkage to the TOC locus. The LOH analysis in sporadic oesophageal cancer we report here is thus consistent with the hypothesis that the tylosis oesophageal cancer susceptibility gene is also involved in the pathogenesis of a proportion of sporadic squamous cell carcinomas of the oesophagus.  相似文献   
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996.
In a postal questionnaire investigation of experiences and attitudes concerning end-of-life decisions among Danish physicians, most of the respondents reported having made decisions involving the hastening of a patient's death, and considered this acceptable. Such decisions were more frequent, and were considered ethically more acceptable, when made with the patient's informed consent than without. Of the respondents, two per cent had participated in assisted suicide, and five per cent had administered a lethal injection at the patient's request, practices considered ethically acceptable by 37 per cent and 34 per cent, respectively, of the respondents. The most frequently cited reasons for opposing such practices were double effect principle, the active killing/allowed-death distinction, and the sanctity of life; and the most frequently cited justifications were respect for the patient's autonomy, the avoidance of unnecessary suffering, and the patient's right to a death with dignity.  相似文献   
997.
Five case reports illustrate the spectrum of ultrasound findings in the postpartum period. When examining patients with symptoms of secondary haemorrhage, the ultrasonographer may find: (i) an empty uterus (no retained tissues): (ii) blood clots which will pass spontaneously; or (iii) retained tissues, which are an indication for evacuation of the uterus. The importance of grey-scale assessment of symptomatic patients is stressed.  相似文献   
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The use of the schwa vowel at cough offset is an automatic production that can be easily prolonged and modified as a phonation-producing device without requesting initial voluntary phonation on the part of the patient. It is presented as a clinical method that was successful for the author with two female patients presenting functional aphonia. The technique lends support to the suggestions by Aronson (1969) and Boone (1971) that the symptomatic approach can be successful with the functional aphonic patient. The clinician should be mindful of the fact that in certain cases of functional aphonia an appropriate referral might be needed to deal with emotional aspects after voice is regained.  相似文献   
1000.
We tested the hypothesis that the slower increase in alveolar oxygen uptake (VO2) at the onset of supine, compared with upright, exercise would be accompanied by a slower rate of increase in leg blood flow (LBF). Seven healthy subjects performed transitions from rest to 40-W knee extension exercise in the upright and supine positions. LBF was measured continuously with pulsed and echo Doppler methods, and VO2 was measured breath by breath at the mouth. At rest, a smaller diameter of the femoral artery in the supine position (P < 0. 05) was compensated by a greater mean blood flow velocity (MBV) (P < 0.05) so that LBF was not different in the two positions. At the end of 6 min of exercise, femoral artery diameter was larger in the upright position and there were no differences in VO2, MBV, or LBF between upright and supine positions. The rates of increase of VO2 and LBF in the transition between rest and 40 W exercise, as evaluated by the mean response time (time to 63% of the increase), were slower in the supine [VO2 = 39.7 +/- 3.8 (SE) s, LBF = 27.6 +/- 3.9 s] than in the upright positions (VO2 = 29.3 +/- 3.0 s, LBF = 17.3 +/- 4.0 s; P < 0.05). These data support our hypothesis that slower increases in alveolar VO2 at the onset of exercise in the supine position are accompanied by a slower increase in LBF.  相似文献   
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