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991.
We investigated the effect of oral contraceptives with low and high estrogen concentration on blood coagulation and thrombogenesis, induced by vascular subendothelium of rabbit aorta exposed to flowing human blood. Twenty healthy women intending to take oral contraceptives were studied [1] before drug ingestion (control), and subsequently during the intake of oral contraceptives with [2] low estrogen content (20 micrograms ethinyl estradiol and 150 micrograms desogestrel per day) and [3] high estrogen content (50 micrograms ethinyl estradiol and 125 micrograms desogestrel per day). All experiments were performed between day 17 and 21 of the menstrual cycle and drug effects were studied during the third tablet cycle. Deposition of fibrin, platelets and platelet thrombi on vascular subendothelium was tested at a defined blood flow and wall shear rate (10 ml/min, 650 s-1) and was quantified by morphometrical techniques. Treatment with the low and high dose contraceptive increased the plasma levels of ethinyl estradiol (728 +/- 139 and 1438 +/- 212 vs. 0 fmol/l [low and high dose vs. control], means +/- SEM, P less than 0.001) and fibrinogen (2.3 +/- 0.1 and 2.6 +/- 0.1 vs. 2.0 +/- 0.1 g/l, P less than 0.05); and decreased antithrombin III activity (95 +/- 3 and 92 +/- 3 vs. 101 +/- 3 %, P less than 0.05). Fibrin deposition on vascular subendothelium was enhanced by the high dose contraceptive only (47 +/- 4 vs. 35 +/- 4 % coverage of the subendothelial surface with fibrin, high dose vs. control, P less than 0.05). The subendothelial deposition of platelets and platelet thrombi was not changed by contraceptive treatment. These results indicate that treatment with high dose contraceptives leads to an increase of fibrin-subendothelial interactions, whereas low dose contraceptives do not significantly alter the blood-subendothelium interactions. observed in this ex vivo model of thrombogenesis. 相似文献
992.
In 1984, in addition to its standard traditional curriculum, Rush Medical College (Chicago, Ill) developed a Socratic problem-based method of teaching basic science material called the alternative curriculum. As part of an evaluation of this new curriculum, students in the two curricula were compared using three traditional measurements: (1) test scores from the National Board of Medical Examiners, Part I; (2) test scores from the National Board of Medical Examiners, Part II; and (3) performance on an oral examination. Alternative curriculum students did not differ significantly from their traditional curriculum classmates on National Board of Medical Examiners, Part I and Part II total scores, although their subset scores on Part I did tend to be lower, reaching significance in one subset area. Differences in performance favoring the traditional curriculum were primarily seen in the early years of the program. Alternative curriculum students in the class matriculated in 1987 scored significantly higher in three of five categories on the oral examination. 相似文献
993.
994.
I D Johnson 《JAMA》1991,265(3):407-8, 410-1
995.
996.
Nonsyndromal autosomal recessive profound childhood deafness will affect about one in 4000 children in western Europe. A nonsyndromal autosomal recessive type of profound childhood deafness was thought to be the cause of deafness in at least eight and probably 12 children from a large family with various consanguineous matings and other family interrelations. Audiograms of all affected deaf children showed a profound childhood deafness with only a very slight variation. Audiometric examinations, such as pure-tone audiometry, high-frequency audiometry, stapedial reflexes, and Bekesy audiometry, of ten obligate or presumed carriers did not show any significant findings that would allow identification of carriers of this autosomal recessive gene. Families like this one seem to be very rare. Large clinically well-studied families like this one are indispensable for gene linkage studies of nonsyndromal autosomal recessive types of profound childhood deafness. Such studies should make it possible to trace the origin of these types of childhood deafness at an early age. In consequence, carrier detection should also become available. 相似文献
997.
A I Eidelman 《The Journal of pediatrics》1989,114(2):340-341
998.
Five cases of unilateral vocal cord paralysis/paresis were diagnosed following extracorporeal membrane oxygenation for newborn respiratory failure. All were right sided and transient in nature. None of the five patients had other findings commonly associated with vocal cord palsy. The extracorporeal membrane oxygenation procedure requires surgical dissection in the carotid sheath on the right side of the neck, an area immediately adjacent to both the vagus and recurrent laryngeal nerve. It is speculated that vocal cord paralysis in these infants was acquired as a result of the extracorporeal membrane oxygenation cannulation. Although the vocal cord paralysis resolved in all cases, two patients had difficult courses after extracorporeal membrane oxygenation. Therefore, laryngoscopic examination should be considered for patients after extracorporeal membrane oxygenation. 相似文献
999.
1000.
Ethmoidal mucocoeles in children 总被引:1,自引:0,他引:1
Children presenting with ethmoidal mucocoeles are rare. Five children are presented with such findings, and the diagnosis, treatment and possible aetiology discussed. C.T. scanning was found to be the investigation of choice, while plain sinus X-rays correlated poorly with the presence of disease. Exenteration through an external approach was found to be satisfactory. In two cases drainage obstruction due to congenital abnormality was thought to be the underlying cause, while in four cases there was a strong history of atopy, indicating allergy as a possible reason for mucocoele formation. 相似文献