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A Espinosa de los Monteros G Roussel N M Neskovic J L Nussbaum 《Journal of neuroscience research》1988,19(2):202-211
A new chemically defined medium consisting of equal parts of Dulbecco modified Eagle's and Ham's F-12 media supplemented with insulin, sodium selenite, putrescine, and D+ galactose, which allows the long-term survival of mature oligodendrocyte pure cultures, is described. Immunohistochemical staining has shown that over 90% of the cells become positive for myelin proteins shortly following subculture. Contaminating astrocytes (2%) do not survive in this medium. Biochemical data have indicated that these purified oligodendrocytes express 2'3'-cyclic nucleotide 3'-phosphohydrolase and UDP-galactose ceramide galactosyltransferase activities. Electron microscopical examination revealed that the oligodendrocytes were mostly of medium-dark type and appeared to be identical to cells cultured in serum-containing medium. The ability to maintain pure oligodendrocyte cultures in such a defined medium will allow investigations concerning exogenous and endogenous factors involved in oligodendrocyte metabolism. 相似文献
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A Parra F Gabi?o A Ramírez H Valencia I Coria A Espinosa de los Monteros 《Contraception》1991,44(5):541-547
The study was undertaken to analyze the basal and metoclopramide-stimulated serum PRL levels in healthy parous women users (group 1, n = 12) and non-users (group 2, n = 12) of a TCu-380 IUD. All women had regular menses and were studied between days 18 to 22 of their cycle; none had lactated nor regularly ingested any type of medication during the last six months. After a 10-12 hour overnight fast, peripheral venous blood samples were obtained through an indwelling catheter at -30, -15 and 0 minutes and at 60, 90 and 120 minutes after oral metoclopramide (10 mg). There were no significant differences in serum PRL between both groups, in basal levels nor throughout the test, whether analyzing the mean values at each sampling time, the sum of PRL levels from 60-120 minutes, or the peak levels. No correlation was observed between PRL levels and any of the clinical or obstetric characteristics of the women in both groups. Serum progesterone was greater than or equal to 4.0 ng/ml in all women. Thus, the use of alpha TCu-380 IUD did not induce any significant changes in basal nor in stimulated serum PRL levels. 相似文献
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Marcos Daccarett MD Gustavo Espinosa MD FACR Fred Rahimi DPM Christopher M. Eckerman DPM Shelley Wayne-Bruton DPM Mark Couture DPM Jason Rosenblum DPM 《The Journal of foot and ankle surgery》2002,41(6):372-378
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma. 相似文献
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The first 97 eyes operated with keratomileusis by two surgeons starting to use this technique are evaluated. The 30- and 90-day postoperative results of this initial experience are reported. Average preoperative myopia was -10.53 D spherical equivalent (range -5.25 to -22.25 D); average refractive correction at 90 days was -10.20 D. Preoperative visual acuities without correction were between 0.01 and 0.15 Snellen scale (20/2000 to 20/133), and 90 days postoperatively they varied between 0.02 and 0.60 Snellen scale (20/1000 to 20/33) with an average of 0.29 (20/69). Average preoperative visual acuity with correction was 0.70 Snellen scale (20/29), and 90 days afterward it was 0.60 Snellen scale (20/33). Preoperative average refractive cylinder was 1.33 D and postoperative was 1.86 D, showing that significant amounts of astigmatism were not induced. 相似文献
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A horizontal double skin island pectoralis major myocutaneous flap with preservation of nipple-areola complex is described, a different modification used to reconstruct a complex defect following radical resection of a locally advanced gingival carcinoma. The skin islands are horizontally separated by a distance of 2.5 cm but rely on one vascular pedicle for their blood supply. The muscle between the skin islands provides the soft tissue bulk between the internal mucosal and external skin lining. The need for a separate segmental flap or a split-thickness skin graft for mucosal lining was eliminated. 相似文献
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During a 5-year interval, 500 women underwent 530 needle localizations (NL) for nonpalpable, mammographically suspicious breast lesions. These lesions were localized using the Homer Mammalok Breast Needle/Wire Localizer (Namic; Glens Falls, NY). Almost one half the NL (260/530) were performed for suspicious calcifications; 19 per cent (49/260) proved to be cancerous. Cancer (CA) was identified 90 times in 88 patients (17%); 64 per cent (58/90) were invasive and 36 per cent (32/90) were noninvasive carcinomas. Eighty per cent of the lesions were 1 cm or smaller. Eighty-four axillary dissections were done and only 7 patients (8%) had axillary metastasis. During the same time interval, 277 women underwent axillary dissection, with or without mastectomy, for palpable breast cancer. Ninety-one per cent (252/277) had invasive carcinomas and 38 per cent (104/277) had axillary metastasis. Estrogen receptor assays (ERA) and progesterone receptor assays (PRA) were similar for both patient populations. The authors conclude that NL is an effective, safe method of detecting highly curable, occult breast cancer. It can be done effectively at a community hospital with results very similar to large university studies. 相似文献
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