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1.
目的:直肠腺瘤和其他疑似为良性的病变应用经肛门内镜切除术并未普及。该项研究旨在评估经肛门内镜切除术的效能和安全性。方法:回顾性研究分析在1993-2004年之间3所斯德哥尔摩医院中经肛门内镜切除术的患,内容包括患自身及病变特性、并发症、随访时间和复发率。结果:180例中共131例行经肛门内镜切除术。160例经组织学诊断为腺瘤,12例为癌瘤,其余8例分别为增生、纤维化或正常黏膜。直肠腺瘤患中,77例仅行单次经肛门内镜切除术,16例因巨大腺瘤而多次行该手术,27例因复发而需另行经肛门内镜切除术或其他手术。中位复发时间为7个月,但未出现直肠癌。16例手术患出现并发症。2例患必须行Hartman手术,1例因肠穿孔,另1例因出血。手术期间无死亡。未复发的中位随访期为32个月(极差0—67)。[编按] 相似文献
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Structural vertebral changes in the horizontal plane in idiopathic scoliosis and the long-term corrective effect of spine instrumentation 总被引:1,自引:0,他引:1
Summary The rotation and structural changes of the apex vertebra in the horizontal plane as well as of the thoracic cage deformity were quantified by measurements on computed tomography (CT) scans from patients with right convex thoracic idiopathic scoliosis (IS). The CT scans were obtained from 12 patients with moderate scoliosis (mean Cobb angle 25.8°, r 13°–30°) and from 33 with severe scoliosis (mean Cobb angle 46.2°, r 35°–71°). In addition, CT scans of thoracic vertebrae from 15 patients without scoliosis were used as reference material. Ten of the scoliotic cases had had Cotrel-Dubousset instrumentation (CDI) and posterior fusion and had entered a longitudinal study on the effect of operative correction on the re-modelling of the apical vertebra. An increasingly asymmetrical vertebral body, transverse process angle, pedicle width and canal width were found in the groups with scoliosis as compared with the reference material. Vertebral rotation and rib hump index were significantly larger in patients with early and advanced scoliosis than in normal subjects. The modelling angle of the vertebral body, the transverse process angle index and the vertebral rotation in relation to the middle axis of the thoracic cage were significantly greater in patients with severe than with moderate scoliosis. The results of this longitudinal study suggest that the structural changes of the apical vertebra regress 2 years or more after CD instrumentation. 相似文献
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P Havránek H Hedlund A Rubenson D Güth M Husberg T Frykberg L T Larsson 《Journal of pediatric surgery》1992,27(7):916-918
Thirty-four patients operated with sacrococcygeal teratoma in Sweden between 1978 and 1989 were reviewed. Twenty-five children were available for functional follow-up. The patients and their parents were interviewed for bowel and micturition habits. Fourteen patients from this number were subjected to anorectal manometry (56%). Fifteen children reported normal bowel habits (60%). In 10 patients (40%) soiling was observed. However, four of them were under 3 years of age and wearing diapers, which made the functional evaluation difficult. The manometries showed normal and resting tone and squeezing pressures in 10 patients and subnormal values in four patients who also had soiling problems. All investigated children showed normal rectoanal inhibition reflex. Twenty-one patients reported normal micturition, in four (16%) urinary incontinence was recorded. Two of the latter children required intermittent clean catheterization, one was on medication and the last one lives without any treatment. No difference in functional outcome was noted between patients with intrapelvic or extrapelvic tumor location. Retrospectively, it is not possible to know whether the observed functional outcome is due to tumor growth or the result of surgery. Preoperative clinical investigation and in some cases anorectal manometry and cystometry could theoretically resolve this problem. 相似文献
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Britta Hedlund Maud Lorentz Peter Arhem 《Basic & clinical pharmacology & toxicology》1987,60(2):156-160
Abstract: Responses of NIE-115 neuroblastoma cells to application of carbachol were studied using intracellular recording techniques. Activation of muscarinic cholinergic receptors by carbachol resulted in a depolarization of the cells. The response was blocked by pirenzepine (1 μM) and by CoCl2 (5 mM), verapamil (10 μM) and gallopamil (10 μM), and prolonged by quinine (5 mM). It is suggested that muscarinic receptors increase the membrane calcium permeability, and that the influx of calcium activates calcium dependent potassium channels. 相似文献
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Laurie M. Lomasney John F. Madden Wagdy S. Rizk Lawrence W. Hedlund Salutorio Martinez Robert E. Coleman William J. Richardson H. Dirk Sostman 《Journal of magnetic resonance imaging : JMRI》1994,4(3):441-449
Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise. 相似文献
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Jos Angel Gonzalo Ana Gonzlez-García Terje Kalland Gunnar Hedlund Carlos Martínez-A Guido Kroemer 《European journal of immunology》1993,23(9):2372-2374
Intravenous injections of 50 μ.g Staphylococcus aureus enterotoxin B (SEB) or bacterial lipopolysaccharide (LPS) are lethal, provided that mice are simultaneously sensitized with either N-galactosamine (GalN) or the anti-glucocorticoid RU-38486. Similar to the synthetic glucocorticoid (GC) receptor agonist dexamethasone, pharmacological doses of the immunomodulator linomide (quinoline-3-carboxamide) prevent death in all four models of lethal septic shock (LPS + GalN, LPS + RU-38486, SEB + GalN, and SEB + RU-38486) and inhibit the secretion of tumor necrosis factor, one of the major intermediate effector molecules of SEB and LPS toxicity. In this system, cyclosporine A (CsA), although effective in suppressing SEB toxicity, fails to counteract the lethal effect of LPS. This observation, together with the fact that linomide acts in the presence of excess amounts of GC receptor antagonist, indicates that linomide functions in a different way to that of known immunosuppressive agents like CsA and GC. 相似文献
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Targeting of human cytotoxic T lymphocytes to MHC class II-expressing cells by staphylococcal enterotoxins. 下载免费PDF全文
The staphylococcal enterotoxins (SE) comprise a family of structurally related phage-encoded bacterial proteins, which are the most potent mitogens known for murine and human T lymphocytes. In this report we describe a novel cytotoxic mechanism, where SE directs human CD3+ T lymphocytes to mediate strong cytotoxicity against target cells of irrelevant nominal specificity. The SE-dependent cellular cytotoxicity (SDCC) occurred at picomolar concentrations of SE and involved the initial binding of the SE to the target cells and subsequent triggering of the cytotoxic T cells. SDCC was induced by SEA, SEB, SEC1 and SED, which indicates that this is a common property conserved among all SE. Certain antibodies to the HLA-DR molecule efficiently blocked SDCC. Major histocompatibility complex (MHC) class II+ RAJI cells and HLA-DR-transfected murine L cells were sensitive to SDCC, whereas the MHC class II- RJ.2.2.5 RAJI cell mutant and untransfected L cells were completely resistant to SDCC. These results demonstrate that the MHC class II antigen is the target molecule in SDCC. HLA-DR molecules acted as receptors for SE and the complex was recognized by T lymphocytes in a polyclonal fashion. SDCC was mediated by allospecific cytotoxic CD8+ T cells, by cloned CD8+ T cells and by fresh human peripheral blood mononuclear cells. The SDCC phenomenon provides a rapid, potent and specific mechanism for elimination of HLA-DR+ target cells. We suggest that SDCC is an important combat strategy, employed by the bacteria to avoid specific MHC class II antigen-dependent immune recognition, by inducing T-cell dependent autologous lysis of MHC class II-expressing cells. 相似文献