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1.
以18-甲基-17β-羟基-17α-乙炔基-雌甾-4-烯-3-酮(18-甲基炔诺酮),17β-羟基-17α-乙缺基-雌甾-4-烯-3-酮(炔诺酮),17β-羟基-17α-乙炔基-雄甾-4-烯-3-酮(妊娠素)和17a-羟基孕甾-4-烯-3,20二酮(17α-羟基黄体酮)为原料,经NaBH,还原、脱水、双键转位和酯化等反应合成一系列3,5-甾二烯化合物,用1HNMR和MS证明了它们的结构。动物筛选结果表明,17β-丙酰氧基-17α-乙炔基-雌甾-3,5-二烯(IVb2有明显的抗早孕活性。中断早期妊娠的作用似与其雌激素活性有关。 相似文献
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GD Cramer DJ Allen LJA DiDio W Potvin R Brinker 《Surgical and radiologic anatomy : SRA》1990,12(4):287-290
Summary Accurate volume determination of the encephalic ventricles is of importance in several clinical conditions, including Alzheimer's presenile dementia, schizophrenia, and benign intracranial hypertension. Previous studies have investigated the accuracy with which magnetic resonance imaging (MRI) can be used in clinical practice to evaluate the encephalic ventricles. However, adequate evaluation of pathological conditions depends on a sufficient amount of morphometric data from normal subjects. To begin establishing this data base for normal subjects, we evaluated the MRI scans of 38 subjects found to have no apparent pathology and calculated the ventricular volume in each case by using methods previously developed in our laboratory. The results were then compared with published volumes determined from studies that used either ventricular casts or computerized tomographic scans. The average total ventricular volume for all 38 subjects was 17.4 cm3, while that for males was 16.3 cm3 and that for females was 18.0 cm3. A small but significant correlation was found between age of subject and ventricular volume, with ventricular size increasing with age.
Evaluation du volume des ventricules cérébraux à partir des images obtenues en résonance magnétique nucléaire chez 38 sujets humains
Résumé La détermination exacte du volume des ventricules cérébraux est importante en clinique comme par exemple dans la démence présénile d'Alzheimer, la schizophrénie et l'hypertension intracrânienne bénigne. Des études antérieures ont étudié la fiabilité de la résonance magnétique nucléaire en pratique clinique pour évaluer le volume des ventricules cérébraux. Toutefois une évaluation correcte dans les conditions pathologiques implique une bonne connaissance des données morphométriques du sujet normal. Pour établir ces données sur « le sujet normal », nous avons étudié les coupes obtenues en IRM chez 38 sujets apparemment indemnes de toute pathologie; nous avons calculé le volume ventriculaire dans chaque cas en utilisant des méthodes mises au point auparavant dans notre laboratoire. Les résultats ont été ensuite comparés avec ceux obtenus par d'autres études utilisant soit des moules ventriculaires, soit des coupes tomographiques computérisées. Le volume ventriculaire total moyen chez 38 sujets est de 17,4 cm3, mais il est chez les sujets masculins de 16,3 cm3 et chez les sujets de sexe féminin de 18 cm3. Une corrélation faible mais significative a été trouvée entre l'âge du sujet et le volume ventriculaire, étant entendu que la taille du ventricule augmente avec l'âge.相似文献
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Congenital pulmonary atresia with ventricular septal defect: angiographic and surgical correlates 总被引:1,自引:0,他引:1
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries. 相似文献
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Vasiliki-Kalliopi Bournia George Kitas Athanasios D. Protogerou Petros P. Sfikakis 《Modern rheumatology / the Japan Rheumatism Association》2017,27(4):559-569
Although large-scale population studies have shown that non-steroidal anti-inflammatory drugs (NSAIDs) increase the risk of myocardial infarction, this is not confirmed in patients with rheumatoid arthritis (RA). Herein, we review the litterature on the differential effects of NSAIDs on cardiovascular risk in osteoarthritis (OA) versus RA and discuss possible explanations for this discrepancy. To assess a potential additive effect of age in non-RA populations, we compared weighted mean age between RA patients and unselected NSAID users included in cohort and case–control studies that estimate the cardiovascular risk of NSAIDs, assuming that the main indication for NSAID usage in elderly populations is OA. Our hypothesis that advanced age in osteoarthtitis compared to RA patients confounds the effect of NSAIDs on cardiovasular risk was not confirmed. Several other hypotheses that can be proposed to explain this counterintuitive effect of NSAIDs on the cardiovascular risk of RA patients are discussed. We conclude that patients with RA have a lower cardiovascular disease risk associated with the use of NSAIDs, probably due to the nature of their disease per se, until further research indicates differently. 相似文献
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Douglas KM Potter T Treharne GJ Obrenovic K Hale ED Pace A Mitton D Erb N Whallett A Delamere JP Kitas GD 《Rheumatology (Oxford, England)》2005,44(1):80-82
OBJECTIVES: To determine the preferences of rheumatology patients for the time and location of their out-patient appointments. METHODS: All patients attending the rheumatology out-patient services at Dudley Group of Hospitals NHS Trust over a 2-week period were asked to complete a purpose-designed, scannable, previously piloted, self-administered questionnaire. RESULTS: Four hundred and nineteen patients completed questionnaires (response rate 87%). Age ranged from 16 to 92 yr; 38% of responders were over 65 yr, 72% were female, 57% had an inflammatory arthritis, 20% had a connective tissue disease, 8% had degenerative joint disease and 15% had another diagnosis; 29% were employed, 51% retired and 20% unemployed. Fewer than 1% of patients would like to be seen at community general practice centres (99.3% would prefer a hospital site). Proximity to their home was the main determinant of hospital choice. Monday was the most popular day for appointments, and days from Tuesday to Friday received equal rankings. Only 0.5% of patients would choose a weekend clinic. Fifty-eight per cent of patients would prefer morning appointments, 24% afternoon appointments and 2% evening appointments; 16% did not mind. Only being employed predicted out-of-hours preference. CONCLUSIONS: In this predominantly suburban, industrialized area, rheumatology out-patients prefer to be seen in the hospital rather than primary care environment, ideally close to their home, with appointments in the morning and on a weekday. These results may be generalizable to other districts and other chronic disease states, but we suggest that similar surveys become part of routine service provision and inform current and future planning. 相似文献
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DZ Loesch F Tassone J Lo HR Slater LV Hills MQ Bui PA Silburn GD Mellick 《Clinical genetics》2013,84(4):382-385
We recently reported a significant increase in the frequency of carriers of grey zone (GZ) alleles of FMR1 gene in Australian males with Parkinson's disease (PD) from Victoria and Tasmania. Here, we report data comparing an independent sample of 817 PD patients from Queensland to 1078 consecutive Australian male newborns from Victoria. We confirmed the earlier finding by observing a significant excess of GZ alleles in PD (4.8%) compared to controls (1.5%). Although both studies provided evidence in support of an association between GZ‐carrier status and increased risk for parkinsonism, the existing evidence in the literature from screening studies remains equivocal and we discuss the need for alternative approaches to resolve the issue. 相似文献