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921.
Boggi U Vistoli F Del Chiaro M Signori S Croce C Bartolo TV Coppelli A Fossati N Marchetti P Del Prato S Mosca F 《Transplantation proceedings》2004,36(4):1090-1092
BACKGROUND: Most solitary pancreas transplants (SPTx) fail due to unrecognized rejection episodes. Consequently, SPTx are monitored by drainage into the bladder or by surveillance biopsies. METHODS: Between April 2001 and June 2003, a consecutive series of 48 SPTx were performed using portal enteric drainage (PED). Rejection episodes were diagnosed empirically, based on the elevated pancreatic enzymes without a surveillance biopsy. Immunosuppression consisted of basiliximab (n = 42) or ATG (n = 6), low-dose steroids, MMF, and tacrolimus. Donors (mean age 28.9 year; range 9 to 54 year) were selected according to standard criteria irrespective of HLA match, although the best HLA matching was considered at the time of graft allocation. RESULTS: After a mean cold ischemia time of 676 minutes (range 475 to 900 minutes), all but two pancreata (95.8%) functioned immediately. Relaparotomy was required in seven cases (14.6%). Three grafts were lost in the early posttransplant period due to hyperacute rejection. Two additional grafts were lost later due to arterial thrombosis or to chronic rejection. After a median follow-up period of 12.2 months (range 0.2 to 27 months) three further recipients were diagnosed with rejection episodes that were reversed with steroid boluses. Actuarial 1-year patient and graft survival rates were 100% and 93.1% and 2-year figures 100% and 88.7%, respectively. At the longest follow-up no recipient was diagnosed with a malignancy. CONCLUSIONS: With current immunosuppression protocols SPTx achieves high rates of insulin independence even without surveillance biopsy or routine use of T-cell-depleting therapies. 相似文献
922.
923.
Abdominal rectopexy for rectal prolapse: a comparison of techniques. 总被引:21,自引:0,他引:21
To compare the methods of abdominal rectopexy and to elucidate the mechanism by which rectopexy restores continence in patients with rectal prolapse, the role of sphincter recovery, rectal morphological changes and improved rectal sensation were assessed in 68 patients (eight men, 60 women) of median age 63 (range 18-83) years undergoing resection rectopexy (n = 29), anterior and posterior Marlex rectopexy (n = 20), posterior Ivalon rectopexy (n = 9) or suture rectopexy (n = 10). Preoperative and postoperative manometry, radiology and electrosensitivity measurements were made. Age and duration of follow-up were similar in all groups and the prolapse was controlled in all patients. Significantly improved continence was seen in all but the Ivalon group. There was no evidence of increasing postoperative constipation. Sphincter length and voluntary contraction were unaltered, but improved resting tone was seen in the resection and suture groups. This was not seen in the prosthetic groups. Improved continence correlated with recovery of resting pressure. Upper and sensation was improved in all groups. Radiological changes did not correlate with improved continence. We conclude that continence is improved by all rectopexy procedures but seems better without prosthetic material. Sphincter recovery seems to be the most important factor. 相似文献
924.
Anismus, or failure of the somatic sphincter apparatus to relax at defecation, has been implicated as a major contributor to the problem of obstructed defecation. Current diagnostic methods depend on laboratory measurements of attempted defecation and the most complex, dynamic proctography has been the mainstay of diagnosis. Using a new computerized ambulatory method of recording sphincter function in these patients at home, we report an 80% reduction in our diagnostic rate suggesting that conventional tests fail to accurately diagnose this condition, probably because they poorly represent the natural physiology of defecation. Treatment of this distressing condition is more complex and a variety of surgical and pharmacological measures have failed. Biofeedback retraining of anorectal function of these patients has been very successful and represents the management of choice.
Resumen El anismus, o sea la falla en el fenómeno de relajación del aparato somático esfinteriano que permite la defecación, ha sido implicado como el factor principal en el problema de la defecación obstruida. Los actuales métodos de diagnóstico, que dependen de mediciones fisiológicas de laboratorio durante el intento de defecación y de la muy compleja proctografía dinámica, han venido a ser esenciales para el diagnóstico. Con la utilización de un novedoso método computadorizado ambulatorio de registro de la función esfinteriana con el paciente en el hogar, podemos informar una reducción de 80% en nuestra tasa de diagnóstico de anismo, lo cual sugiere que las pruebas convencionales fallan en el diagnóstico certero de esta condición, probablemente porque representan de manera muy pobre la fisiología natural de la defecación. El tratamiento de esta incapacitante condición es más complejo y toda una variedad de procedimientos quirúrgicos y farmacológicos han fallado. En estos pacientes el reentrenamiento de la función ano-rectal por biorectroalimentación ha sido muy exitoso y representa la modalidad de manejo preferencial.
Résumé L'anisme, ou impossibilité de relaxation de l'appareil sphincterien de l'anus lors de la défecation, a été impliqué comme facteur majeur dans le problème de constipation. Les méthodes actuelles de diagnostic de l'anisme dépendent des examens de laboratoire; la proctographie dynamique, l'examen le plus complexe, a été, jusqu'à présent, l'examen le plus probant. Avec l'utilisation d'un enregistrement informatisé ambulatoire, nous avons constaté une réduction de 80% dans notre taux de diagnostic, ce qui suggère que les examens conventionels ne font pas de diagnostic correct, probablement parce qu'ils ne tiennent pas bien compte de la physiologie naturelle de la défecation. Le traitement de cette entité inquiètante est complexe et beaucoup des méthodes chirurgicales ou pharmacologiques sont des échecs. Par contre, le biofeedback et l'entrainement anorectal sont souvent couronnés de succès et représentent la méthode therapeutique de choix.相似文献
925.
926.
927.
Blood and plasma viscosity, erythrocyte filtrability and blood gas analysis were determined in 25 subjects with arteriosclerosis obliterans of the lower limbs before and after a muscle exercise test. Thirty-six shear rates between 0 and 230 s1 were studied to obtain viscosity curves, and regression analysis was performed for each curve. Mean viscosity curves for pathologic and control populations were plotted. The purpose of the study was to determine whether viscosity curves for blood and plasma before and after exercise, based on a high number of measurements, can provide information on rheological changes during intermittent claudication. Practically all viscosity curves in pathologic and control subjects could be described using a hyperbolic equation. Plasma as well as blood viscosity increased in pathologic subjects after exercise. However, erythrocyte filtrability and blood gas analysis in pathologic and control subjects, and blood and plasma viscosity in control subjects, showed no statistically significant changes after exercise. It is suggested that muscle exercise in reduced blood flow conditions can alter the aggregation of macromolecular complexes of plasma proteins, which could have an influence on cell components by modifying blood rheological behavior during claudication. 相似文献
928.
Mapping distributed sources of cortical rhythms in mild Alzheimer's disease. A multicentric EEG study 总被引:2,自引:0,他引:2
Babiloni C Binetti G Cassetta E Cerboneschi D Dal Forno G Del Percio C Ferreri F Ferri R Lanuzza B Miniussi C Moretti DV Nobili F Pascual-Marqui RD Rodriguez G Romani GL Salinari S Tecchio F Vitali P Zanetti O Zappasodi F Rossini PM 《NeuroImage》2004,22(1):57-67
The study aimed at mapping (i) the distributed electroencephalographic (EEG) sources specific for mild Alzheimer's disease (AD) compared to vascular dementia (VaD) or normal elderly people (Nold) and (ii) the distributed EEG sources sensitive to the mild AD at different stages of severity. Resting EEG (10-20 electrode montage) was recorded from 48 mild AD, 20 VaD, and 38 Nold subjects. Both AD and VaD patients had 24-17 of mini mental state examination (MMSE). EEG rhythms were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). Cortical EEG sources were modeled by low resolution brain electromagnetic tomography (LORETA). Regarding issue i, there was a decline of central, parietal, temporal, and limbic alpha 1 (low alpha) sources specific for mild AD group with respect to Nold and VaD groups. Furthermore, occipital alpha 1 sources showed a strong decline in mild AD compared to VaD group. Finally, distributed theta sources were largely abnormal in VaD but not in mild AD group. Regarding issue ii, there was a lower power of occipital alpha 1 sources in mild AD subgroup having more severe disease. Compared to previous field studies, this was the first investigation that illustrated the power spectrum profiles at the level of cortical (macroregions) EEG sources in mild AD patients having different severity of the disease with respect to VaD and normal subjects. Future studies should evaluate the clinical usefulness of this approach in early differential diagnosis, disease staging, and therapy monitoring. 相似文献
929.
930.
Many authors have shown that tumor hypoxia exerts its own influence on malignant progression by inducing angiogenetic factors and new blood vessels inside and around the tumor. This event usually suggests a poor prognosis and/or aggressive tumor behavior. The objective of the present study is to compare molecular analysis of angiogenetic factors with microvessel density (MVD) in bladder carcinoma. Twenty-nine consecutive patients underwent transurethral or open surgery for bladder tumors. Neoplastic tissue samples, normal-appearing bladder mucosa and blood samples were taken from each patient. All the tissues underwent mRNA extraction and Northern blot analysis, marked with specific probes for inducible nitric oxide sinthase (iNOS), cyclo-oxygenase-2 (cox-2), vascular endothelial growth factor (VEGF) and were evaluated by gel-electrophoresis. Microvessel density, a quantitative analysis for neoangiogenesis, was also evaluated by using CD31 immunohistochemical assay and compared with both molecular analysis and patient follow-up. Two follow-up for recurrence and/or progression were performed at 74 months and 10 years from surgery respectively. Pathological evaluation demonstrated the presence of superficial transitional cell carcinoma (sTCC) in 15 patients, while 14 had an invasive bladder tumor (iBT). At both 74 months and 10 years follow-up, all patients with lower MVD had a shorter survival time. No significant results were obtained by comparing disease progression or survival rate with VEGF, iNOS and COX-2 levels. A proportional increase of VEGF expression and MVD compared with poor prognosis was the expected outcome of our study. These results were disregarded at both the 1st and the 2nd follow-up. A strong association between MVD>20 and survival rate was noted both in sTCC (p=0.024) and iBT (p>0.001) patients. These results confirm that MVD could be considered a good prognostic factor. The angiogenetic cytokines overexpression found in control tissue samples of sTCC could have clinical significance, either as a macroscopically unidentified diffuse carcinogenetic process or the presence of a systemic immune-response against tumor cells. 相似文献