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991.
Mitral valve replacement was performed in 21 patients using a surgical technique that preserves the entire papillary muscle and chordal apparatus. With this technique, the anterior mitral leaflet is split from the center of the free edge toward the annulus. Bilateral incisions are made from the proximal end of this split to the two mitral commissures, detaching the anterior leaflet from the annulus. These two halves of the leaflet, with all chordae intact (corresponding to the anterolateral and posteromedial papillary muscles), are judiciously trimmed to remove areas of leaflet untethered by chordae tendineae and (when necessary) fibrous thickening; then swung posteriorly and sutured to the posterior mitral annulus using mattress sutures with pledgets. This surgical technique is expected to favor the preservation of left ventricular function and avoid occurrence of irreversible left ventricular dilation/dysfunction, and has been used successfully for calcific and degenerative etiologies, using both tilting disc valves and porcine bioprostheses. It is especially useful in the implantation of tilting disc and bileaflet mechanical prostheses because anterior subvalvular chordae tissue may interfere with the disc excursion and relocated to the posterior leaflet annulus.  相似文献   
992.
993.
Cardiovascular risk factors were studied from 1985 to 1987 in two population samples from the French regions of the Bas-Rhin (BR) (Strasbourg) and the Haute-Garonne (HG) (Toulouse). 1,257 men and women in the BR and 1,323 in the HG, aged 35-64, participated in the survey. A common investigation methodology in harmony with the MONICA protocol, was used. The mean weight was higher among the male (5 kg) and female (6 kg) populations living in the BR than in the HG. Even after age, body mass index and tobacco consumption adjustments, arterial systolic blood pressure was higher in the male population of the BR (145 mm Hg) than in the HG (133 mm Hg). Similar differences were observed among the female population. A higher proportion of hypertensive subjects whatever the sex and the age group was noted in the BR. The proportion of smokers, and the quantity of tobacco they smoked, did not differ between the two centers. Adjusted total cholesterolemia was higher in the HG, with mean differences of 0.32 mmol/l among the men and 0.35 mmol/l among the women. In the case of HDL cholesterol, the differences were 0.23 mmol/l among the men and 0.34 mmol/l among the women, explaining in large part the differences of the mean levels of total cholesterol.  相似文献   
994.
995.
This report presents for the first time the results of carrying out epikeratophakia with tissue lathed at room temperature. Using an experimental model of epikeratophakia in the rabbit, we evaluated tissue handling techniques for the preparation of donor lenticules. Details of the technique are described and the in-vivo and histopathological findings reported.  相似文献   
996.
997.
998.
Neonatal Graves'' disease.   总被引:1,自引:1,他引:0       下载免费PDF全文
A newborn boy was noted by his mother to have a prominent left eye at birth, but an eye examination was delayed until age 7 months, at which time his ophthalmologist diagnosed exophthalmos. Computed tomography was interpreted as showing mild, diffuse, optic nerve thickening bilaterally suggestive of optic nerve gliomas. Subsequent examination in our clinic revealed pseudoproptosis secondary to retraction of the left upper eyelid. Magnetic resonance imaging demonstrated normal orbital structures. The mother was noted to be clinically hyperthyroid, and abnormal thyroid function tests confirmed the diagnosis. Although the infant was euthyroid, neonatal Graves' ophthalmopathy was diagnosed. He was managed by close observation while his mother was treated for her hyperthyroidism.  相似文献   
999.
The diameter of the temporal superior and inferior retinal artery and vein were measured at the optic disk border and 2 mm from the disk center in 264 nonselected normal eyes on the basis of photographs, with correction of magnification. Additionally, the individual ocular magnification factor was determined by Littmann's method. The mean caliber of the artery was 0.113 +/- 0.019 mm at the disk border and 0.118 +/- 0.023 2 mm from the disk center. The corresponding values for the vein were 0.149 +/- 0.026 mm and 0.159 +/- 0.026 mm. The correlations between vessel caliber and disk size were not significant, but the relationship between disk size and the quotient of vessel diameter divided by disk size was highly significant (p less than 0.0001). Vessel diameter can therefore be taken as an independent unit for determining optic disk size in relative and approximately also in absolute units. Thus, mean horizontal disk diameter (1.77 +/- 0.33 mm) corresponded to 16.3 +/- 3.5 artery and 12.3 +/- 2.6 vein diameters (measured at the optic disk border). The mean individual ocular magnification factor was 0.302 +/- 0.017, with a Gauss standard distribution. If the optical characteristics of a photographed eye are not known and the ocular magnification factor is assumed to be 0.302, then 68.3% of all eyes will be covered with an inaccuracy of 5.6% and 95.5% of all eyes with an inaccuracy of 11.2%.  相似文献   
1000.
We examined two patients with unilateral ophthalmologic findings secondary to pansinusitis caused by Bipolaris. Both patients were healthy young men. One patient had a gradual visual loss, whereas the other showed proptosis. Surgical debridement was the primary treatment in both patients. One patient received antifungal therapy, whereas the other was cured with surgery alone.  相似文献   
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