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91.
Attempted treatment of factor H deficiency by liver transplantation   总被引:9,自引:0,他引:9  
Complement factor H (FH) deficiency is one of the causes of atypical hemolytic uremic syndrome (HUS). Most patients with FH deficiency associated HUS progress to end-stage renal disease despite plasma therapy. Moreover, the disease invariably recurs in the graft kidney and causes graft failure. We confirmed FH deficiency in a 30-month-old boy with recurrent HUS of 2 years duration, and attempted an auxiliary partial orthotopic liver transplantation (APOLT) to overcome the sustained intractable dependency on plasma therapy. APOLT restored the plasma FH level, without HUS recurrence, for 7 months. However, thereafter he suffered from serious infectious complications associated with immunosuppression and finally died 11 months after APOLT. In conclusion, although APOLT showed clinical and laboratory improvement for some period in this patient, the final fatal outcome suggests that liver transplantation should be cautiously applied to patients with HUS associated with FH deficiency.  相似文献   
92.
Percutaneous nonvascular splenic intervention: a 10-year review   总被引:6,自引:0,他引:6  
OBJECTIVE: We performed a retrospective review of our experiences with percutaneous splenic interventions to evaluate the safety and usefulness of these procedures. We examined both the success rate and the complication rate. MATERIALS AND METHODS: We used our electronic database to perform a retrospective analysis of patients treated from January 1990 to December 2000. Thirty-nine imaging-guided percutaneous splenic procedures were performed in 38 patients: 27 men and 11 women who ranged in age from 17 to 83 years (mean age, 56.5 years). For 28 procedures, sonographic guidance was used, and for 11, CT guidance was used. Procedures performed included splenic biopsy (n = 24), fluid aspiration (n = 8), and fluid drainage (n = 7). RESULTS: Splenic biopsy was successful in 91% of the procedures; fluid aspiration, in 100%; and fluid drainage, in 86%. The overall complication rate was 10.3%, with three patients requiring emergency splenectomy as a result of massive bleeding after the procedure. Two of these patients had previously unrecognized vascular tumors, and one had concomitant refractory thrombocytopenia. CONCLUSION: This study suggests that splenic biopsy can be performed safely and is of considerable value in diagnosis. Our findings also show that percutaneous catheter drainage of splenic abscesses is successful and that splenectomy should be reserved for failed percutaneous drainage. The complications that occur after procedures on vascular tumors emphasize the importance of requiring normal coagulation parameters before the procedure because the vascular nature of the lesion may be difficult to recognize on imaging before the procedure.  相似文献   
93.
A mixed-flow blood pump for long-term applications has been developed at the Helmholtz-Institute in Aachen, Germany. Central features of this implantable pump are a centrally integrated motor, a blood-immersed mechanical bearing, magnetic coupling of the impeller, and a shrouded impeller, which allows a relatively wide clearance. The aim of the study was a numerical analysis of hydraulic and hemolytic properties of different impeller design configurations. In vitro testing and numerical simulation techniques (computational fluid dynamics [CFD]) were applied to achieve a comprehensive overview. Pressure-flow charts were experimentally measured in a mock loop in order to validate the CFD data. In vitro hemolysis tests were performed at the main operating point of each impeller design. General flow patterns, pressure-flow charts, secondary flow rates, torque, and axial forces on the impeller were calculated by means of CFD. Furthermore, based on streak line techniques, shear stress (stress loading), exposure times, and volume percentage with critical stress loading have been determined. Comparison of CFD data with pressure head measurements showed excel-lent agreement. Also, impressive trend conformity was observed between in-vitro hemolysis results and numerical data. Comparison of design variations yielded clear trends and results. Design C revealed the best hydraulic and hemolytic properties and was chosen as the final design for the mixed-flow rotary blood pump.  相似文献   
94.
Biodegradable implants for Pipkin fractures   总被引:3,自引:0,他引:3  
The current study was designed to clarify whether biodegradable poly-L/DL lactide pins provide an operative alternative for fixation of Pipkin fractures. Nine patients with Pipkin fractures (one with Pipkin Type I, one with Pipkin Type II, and seven with Pipkin Type IV fractures) were treated surgically between 1996 and 2002. In all patients, the femoral head fractures were fixed with biodegradable, 2.7-mm and 2.0-mm polylactide pins. Eight patients were followed up for an average of 54.2 months. One patient died before the final followup. Eight fractures healed uneventfully. In one patient, a persisting femoral head defect led to posttraumatic arthritis requiring insertion of a femoral endoprosthesis at 1 year. The average range of motion of the affected hips of all patients at followup was 109 degrees -0 degrees -0 degrees in flexion and extension. External and internal rotation averaged 37 degrees -0 degrees -29 degrees . One patient had Brooker Grade I heterotopic ossification develop, and another had a Grade II heterotopic develop. Merle d'Aubigne and Postel ratings showed two excellent and five satisfactory results (average score, 13.1). Adverse effects from the polylactide implants were not observed. Pipkin fractures can be fixed successfully with biodegradable polylactide pins.  相似文献   
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In this study Fourier analysis was applied to condensed images of gastric emptying with the aim of evaluating the amplitude and frequency of gastric contractions as well as gastric emptying in patients with various well-defined disorders. In 15 controls, 65 patients with progressive systemic sclerosis (PSS), 41 patients with diabetes mellitus type I (DM), 12 patients with pyloric stenosis and 9 patients who had undergone gastric surgery, gastric emptying was determined after ingestion of a semi-solid test meal. In addition, condensed images were generated to evaluate the amplitude and frequency of gastric contractions by means of Fourier analysis. In PSS and DM patients, gastric emptying and contraction amplitudes were significantly reduced (P<0.01). Patients with pyloric stenosis displayed regular peristalsis but significantly delayed emptying (P<0.01). Patients who had undergone gastric surgery showed normal or rapid gastric emptying associated with decreased amplitudes (P<0.01). The frequency of gastric contractions in the patient groups was not different from that in controls. This study showed Fourier analysis of condensed images to be a rapid and feasible approach for the evaluation of gastric contractions. Depending on the underlying disorder, gastric emptying and peristalsis showed both corresponding and discrepant findings. Data on gastric contractions provided additional information compared with results obtained by conventional emptying studies. Therefore, both parameters should be routinely assessed to further improve characterisation of gastric dysfunction by scintigraphy.  相似文献   
99.
We have carried out a study with the aim of investigating the association between single nucleotide polymorphisms (SNPs) of the IL-1 gene cluster and childhood IgA nephropathy (IgAN). SNPs of the IL-1α, IL-1β, and IL-1 receptor antagonist (RN) genes (IL1A, IL1B, and IL1RN, respectively) were analyzed in 182 patients with childhood IgAN and in 500 healthy controls. The IgAN patients were also dichotomized and compared with respect to proteinuria (<4 mg and ≥4 mg/m2 per hour, respectively), the presence or absence of podocyte foot process effacement, and the presence of pathologically early and advanced disease markers, such as interstitial fibrosis, tubular atrophy, or global sclerosis. Significant differences in SNP frequencies were observed for the IL1B and IL1RN genes (rs1143627, rs3917356, and rs1143633 in the IL1B gene, and rs928940, rs439154, and rs315951 in the IL1RN gene). Moreover, rs1143627, rs3917356, and rs1143633 of IL1B were found to be significantly associated with the presence of podocyte foot process effacement. Our results suggest that the IL1B and IL1RN genes are associated with increased susceptibility to IgAN in children. They also suggest that the development of proteinuria in IgAN is related to IL1A and that podocyte foot process effacement is associated with IL1B.  相似文献   
100.
Korean ginseng and mountain ginseng (Panax ginseng CA Meyer) are important traditional herbal plants whose ginsenosides are generally accepted as serving to improve sexual functions, such as penile erection. We investigated the effects of tissue-cultured mountain ginseng extract (TMGE) on male patients with erectile dysfunction (ED). A double-blind, placebo-controlled study was conducted with 143 patients experiencing ED. Over the course of 8 weeks, one group took 1 000 mg of TMGE twice a day, and the other group took 1 000 mg of placebo twice a day. The effects of the TMGE and the placebo were analyzed using the Korean version of the International Index of Erectile Function (IIEF) questionnaire. A total of 86 patients completed 8 weeks of treatment. The scores on the five domains of the IIEF after medication were significantly higher than the baseline scores in the group treated with TMGE (P 〈 0.05), whereas no significant improvement was observed in the placebo group (P 〉 0.05). Erectile function and overall satisfaction scores after medication were significantly higher in the TMGE group than in the placebo group (P 〈 0.05). Erectile function of patients in the TMGE-treated group significantly improved, suggesting that TMGE could be utilized for improving erectile function in male patients.  相似文献   
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