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1.
Two cases of a previously undescribed condition are reported. Both patients had an extension contracture of the cervical spine, secondary to a tight ligamentum nuchae. This condition has not been described in patients without an underlying disease process.  相似文献   
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硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
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The clinical features and management of 17 cases of detached extraocular muscles are described. They are classified into four groups: (1) the muscle which is cut and lost during squint surgery, (2) the muscle which breaks during squint surgery, (3) the muscle which slips following squint surgery, and (4) the muscle which is damaged during facial or orbital trauma. The prognosis for group 1 is poor whereas groups 2-4 have a good chance of successful muscle relocation.  相似文献   
6.
Résumé D'étiologie toujours inconnue, la scoliose idiopathique de l'adolescent ne peut être traitée efficacement que si le dépistage est très précoce, entre 8 et 10 ans. La preuve de l'évolutivité angulaire doit être faite avant d'entreprendre un traitement orthopédique, dont l'objectif sera de contrôler l'aggravation liée à la poussée de croissance pubertaire. De nouveaux protocoles à temps partiel sont actuellement à l'étude et s'adresseront à des courbures peu sévères et bien réductibles. Les indications opératoires sont posées en cas d'échec ou d'intolérance au traitement orthopédique. Les limites angulaires pour de telles interventions semblent diminuer progressivement, les techniques devenant plus fiables. On accorde par ailleurs de plus en plus d'importance au plan sagittal, compte tenu de la mauvaise tolérance à long terme des lordoses thoraciques. Malgré les progrès techniques, la réalisation d'une arthrodèse solide avec une greffe abondante reste le seul garant de la stabilité angulaire. L'évolution et l'histoire naturelle des courbures congénitales du rachis sont actuellement bien connues, ainsi que les malformations viscérales habituellement associées. La surveillance radiographique dès le plus jeune âge permet d'évaluer l'asymétrie de croissance vertébrale dans le plan frontal et sagittal. Ceci permet de proposer en cas d'évolutivité un traitement à visée étiologique précoce, sous forme d'une hémi arthrodèse et épiphysiodèse convexe, antérieure et postérieure pour freiner l'hypercroissance du côté de la malformation. Pour les formes dépistées plus tardivement, une greffe postérieure avec ou sans matériel est l'indication classique, en évitant absolument toute manoeuvre de distraction qui comporte un risque de complication neurologique, en particulier en cas de composante cyphotique associée.
Idiopathic and congenital scoliosis
Summary The exact etiology of idiopathic scoliosis is still unknown and therefore the only way to improve the prognosis is to recommend an early screening program, between 8 and 10 years of age. Angular progression must be proven for every curve before any brace application. The goal of such a treatment is to control curve progression during the adolescent growth spur. Recent part-time bracing programs have been proposed for low angle and flexible curves. Surgery is indicated in case of failure or non compliance of the conservative treatment. Currently the angular limits for surgery seem to decrease, as a result of improved surgical techniques. Sagittal unbalance and loss of thoracic lordosis are of major importance for the treatment choice, since their poor outcome in the adult population. Despite technical improvements, the quality of a solid fusion is the most important factor for long lasting results. The natural history and evolution of congenital spine deformities have been precisely documented, as well as the frequently associated visceral problems. Repeated curve measurements in young children will evaluate the growth potential asymetry in the coronal and sagittal planes. In case of rapidly progressive curves, an early surgical treatment can be proposed, consisting in convex anterior and posterior hemiarthrodesis, producing an epiphysiodesis effect of the overgrowing convex side. For cases diagnosed in older ages, the classic indication is a posterior fusion, with or without instrumentation. It is important to avoid any excessive distraction, because of a high risk of neurological complications, especially in case of an associated kyphotic deformity.
Travail présenté aux Actualités. en Orthopédie Pédiatrique organisées par le Dr Cl. Karger, le 19 au 21 mars 1992 à Aubure  相似文献   
7.
The study investigates the correlation between oocyte maturity and fertilization and a variety of hormonal parameters in follicular fluid and ovarian granulosa cells. A methodology for purification of granulosa cells from contaminating blood cells is also established. A total of 63 follicular aspirates were collected at oocyte retrieval from 30 women superovulated using the long luteinizing hormone- releasing hormone (LHRH analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone, testosterone and human chorionic gonadotrophin (HCG) were quantified in follicular fluid and granulosa cells were immunostained for human chorionic gonadotrophin. Immunopurification of granulosa cells from contaminating blood cells was performed. HCG in follicular fluid was significantly high in follicles yielding immature (grade 3) oocytes (P=0.002); there was no correlation with fertilization. Aspirates from follicles containing mature (grade 1) oocytes and oocytes that subsequently fertilized had significantly more granulosa cells immunobound to HCG (P < 0.001, P=0.02). Moreover, the immunomagnetic purification technique provided >98% pure population of granulosa cells. The data demonstrate that HCG in follicular fluid and on granulosa cells may help to predict oocyte maturity and fertilization. Furthermore, immunomagnetic beads provide a reliable procedure for the purification of ovarian granulosa cells.   相似文献   
8.
Fibroblasts consist of heterogeneous subpopulations that have distinct roles in fibrotic responses. Previously we reported enhanced proliferation in response to fibrogenic growth factors and selective activation of latent transforming growth factor (TGF)-beta in fibroblasts lacking cell surface expression of Thy-1 glycoprotein, suggesting that Thy-1 modulates the fibrogenic potential of fibroblasts. Here we report that compared to controls Thy-1-/- C57BL/6 mice displayed more severe histopathological lung fibrosis, greater accumulation of lung collagen, and increased TGF-beta activation in the lungs 14 days after intratracheal bleomycin. The majority of cells demonstrating TGF-beta activation and myofibroblast differentiation in bleomycin-induced lesions were Thy-1-negative. Histological sections from patients with idiopathic pulmonary fibrosis demonstrated absent Thy-1 staining within fibroblastic foci. Normal lung fibroblasts, in both mice and humans, were predominantly Thy-1-positive. The fibrogenic cytokines interleukin-1 and tumor necrosis factor-alpha induced loss of fibroblast Thy-1 surface expression in vitro, which was associated with Thy-1 shedding, Smad phosphorylation, and myofibroblast differentiation. These results suggest that fibrogenic injury promotes loss of lung fibroblast Thy-1 expression, resulting in enhanced fibrogenesis.  相似文献   
9.
Glycogen storage disease due to phosphorylase kinase deficiency occurs in several variants that differ in mode of inheritance and tissue- specificity. This heterogeneity is suspected to be largely due to mutations affecting different subunits and isoforms of phosphorylase kinase. The gene of the ubiquitously expressed beta subunit, PHKB, was a candidate for involvement in autosomally transmitted phosphorylase kinase deficiency of liver and muscle. To identify such mutations, the complete PHKB coding sequence was amplified by RT-PCR of RNA isolated from blood samples of patients and analyzed by direct sequencing of PCR products. The characterization of mutations was complemented by PCR of genomic DNA. In one female and four male patients, we identified five independent nonsense mutations (Y418ter; R428ter; Y974H+E975ter; Q656ter in two cases), one single-base insertion in codon N421, one splice-site mutation affecting exon 31, and a large deletion involving the loss of exon 8. Although these severe translation-disrupting mutations occur in constitutively expressed sequences of the only known beta subunit gene of phosphorylase kinase, PHKB, they are associated with a surprisingly mild clinical phenotype, affecting virtually only the liver, and relatively high residual enzyme activity of approximately 10%.   相似文献   
10.
The hammerhead ribozyme is a small catalytic RNA molecule. Potential hammerhead ribozymes that possess a catalytic domain and flanking sequence complementary to a target mRNA can cleave in trans at a putative cleavage site within the target molecule. We have investigated the potential of hammerhead ribozymes to down-regulate the product of the fibrillin-1 gene (FBN1). Fibrillin is a 347 kDa glycoprotein that is a major constituent of the elastin-associated microfibrils. Mutations in the FBN1 gene are responsible for Marfan syndrome (MFS), a common systemic disorder of the connective tissue. Many FBN1 mutations responsible for MFS appear to act in a dominant-negative fashion, raising the possibility that reduction of the amount of product from the mutant FBN1 allele might be a valid therapeutic approach for MFS. A trans-acting hammerhead ribozyme (FBN1-RZ1) targeted to the 5' end of the human FBN1 mRNA has been designed and synthesized, and shown to cleave its target efficiently in vitro. FBN1-RZ1 cleavage is magnesium dependent and efficient at both 37 and 50 degrees C. Delivery of the FBN1-RZ1 ribozyme into cultured dermal fibroblasts, by receptor- mediated endocytosis of a ribozyme-transferrin-polylysine complex, specifically reduces both cellular FBN1 mRNA and the deposition of fibrillin in the extracellular matrix. These results suggest that the use of hammerhead ribozymes is a valid approach to the study of fibrillin gene expression and possibly to the development of a therapeutic approach to MFS.   相似文献   
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