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BACKGROUND: Posterior spinal procedures through tubular exposures have been described. However, tubes restrain visibility and require co-axial instrument manipulation, increasing difficulty and potentially compromising surgical results. An independent-blade retractor system overcomes the obstacles of working through a tube and has been used to perform minimally-disruptive decompression and instrumented tranforaminal lumbar interbody fusion (TLIF). PURPOSE: To evaluate the advantages to patient recovery and surgical efficacy of this technique. METHODS/RESULTS: Retrospective review of technique employing a minimally-disruptive approach to decompression and transforaminal lumber interbody fusion (TLIF). CONCLUSIONS: Minimally-disruptive decompression and instrumented TLIF can be performed in a safe and effective manner using an independent-blade retractor system. Relative to traditional-open techniques, surgical goals can be accomplished, but with the benefits of minimally-disruptive surgery.  相似文献   
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OBJECTIVE: To measure the effect of androgens or aromatase activity as an index of androgen responsiveness in patients with androgen insensitivity. DESIGN: Genital skin fibroblasts were established in culture using primary skin explants obtained from normal males at the time of circumcision and from androgen insensitive patients who had surgery either for gonadectomy (complete androgen insensitivity syndrome) or for reconstruction of the external genitalia (partial androgen insensitivity syndrome). PATIENTS: Foreskin samples were obtained at the time of circumcision in 27 normal males. Scrotal or labia majora skin was obtained at the time of surgery from 14 patients with the complete and 22 with the partial forms of the androgen insensitivity syndrome. MEASUREMENTS: Basal and stimulated levels of aromatase activity were measured in genital skin fibroblasts following preincubation with natural and synthetic, nonmetabolizable androgens. RESULTS: Following a 48-hour preincubation with testosterone or dihydrotestosterone, there was a five to six-fold stimulation of aromatase activity in normal fibroblasts. Mibolerone, a synthetic androgen, produced similar results. The stimulatory effect was blocked by anti-androgens. Seven patients with partial androgen insensitivity, of whom four were either receptor deficient or showed a qualitative defect in androgen binding, had reduced mibolerone induced stimulation of aromatase activity. All ten patients with receptor negative complete androgen insensitivity had an absent response. There was no aromatase induction in a further three patients with complete androgen insensitivity who were receptor positive. Two siblings in the latter group had an exon deletion encoding for part of the DNA binding domain of the androgen receptor. CONCLUSIONS: Androgens stimulate aromatase activity in genital skin fibroblasts from normals. The response is mediated via the androgen receptor and can be decreased or absent in patients with the androgen insensitivity syndrome. This may be a useful in-vitro marker of androgen responsiveness in such patients.  相似文献   
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. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome (D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques. Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral blood neutrophil. Received August 17, 1995; received in revised form and accepted November 27, 1995  相似文献   
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SUMMARY. Samples from 1828 donations were screened for anti-HBc at seven sites in the UK using kits supplied by 10 manufacturers. Only 10 (0.55%) donations were considered to have true anti-HBc reactivity and these were detected by all 10 kits. Additional markers of HBV infection were found in nine of these 10 donations. Additional reactives were found by all kits, the number ranging from 1 to 43.
In the four more specific kits, the 10 true reactives were clearly distinguished from the 'false reactives' by the strength of the reaction. It is concluded that the reliance on a single ELISA test for anti-HBc diagnosis is unwise. The use of a second test known to be more specific than the screening ELISA is recommended.  相似文献   
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