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991.
Outcome of patients suffering from traumatic brain injury (TBI) depends on the development of secondary brain damage. In this context, recent studies underlined the role of the natriuretic peptides- atrial natriuretic peptide and brain natriuretic peptide (BNP)-in aneurysmatic subarachnoidal hemorrhage (SAH). Especially BNP correlates with intracranial pressure and clinical outcome after SAH. Since its role in TBI remains unclear, the intracranial and systemic concentrations of N-terminal (NT)-proBNP were analyzed in patients suffering from severe TBI. We measured NT-proBNP levels in cerebrospinal fluid (CSF) and serum of 14 patients suffering from severe TBI (GCS15 mm Hg (n=6), the serum (800+/-150 pg/mL) and CSF levels (55+/-9 pg/mL) of NT-proBNP were significantly increased after 24 h, as compared to patients with ICP15 mm Hg. Further studies are currently performed to elucidate the physiologic role of NT-proBNP in TBI.  相似文献   
992.
BACKGROUND: To overcome disadvantages of serum creatinine two strategies have been suggested to identify patients with reduced glomerular filtration rate (GFR). On the one hand, the Modification of Diet in Renal Disease (MDRD) equation is now recommended to classify the stage of chronic kidney disease. On the other hand, cystatin C (Cys C) has been investigated in numerous studies, finding a higher sensitivity than creatinine in detecting diminished GFR. To date, no comparison of both strategies in patients after renal transplantation has been performed. METHODS: One hundred and five consecutive renal transplant recipients underwent (99m)Tc-DTPA-- clearance measurement. Simultaneously, MDRD estimates were calculated and Cys C serum levels were determined. ROC analyses were performed at different decision points from 20 to 70 mL/min/1.73 m(2). RESULTS: Although the area under the curve did not differ significantly between MDRD and Cys C within the tested GFR range, the AUC for Cys C tended to be higher when GFR exceeded 55 mL/min/1.73 m(2). A significantly higher diagnostic accuracy for Cys C compared with MDRD (p = 0.045 at 65 mL/min/1.73 m(2)) was found when investigating the subgroup of patients with well-functioning grafts (GFR>40 mL/min/1.73 m(2)). CONCLUSION: MDRD equation is equivalent to Cys C measurement in renal transplant recipients. As availability of MDRD is superior to Cys C, we recommend GFR estimation using the MDRD equation. Nevertheless, Cys C may serve as a confirmation test of high MDRD estimates in patients with well-functioning grafts because of superior accuracy in these patients.  相似文献   
993.
994.
OBJECTIVE: To explore the rate of significant upgrading from biopsy to radical prostatectomy (RP) specimens in a contemporary cohort, and to develop a prognostic model capable of predicting the probability of significant upgrading, as previous reports indicate that up to 43% of men with low-grade prostate cancer at biopsy will be diagnosed with high-grade cancer at RP. PATIENTS AND METHODS: The study cohort comprised 4789 men (median age 63 years, range 39-82) treated with RP, with available clinical stage, prostate-specific antigen levels, biopsy and RP Gleason sum values. These variables were used as predictors in multivariate logistic regression models (LRMs) addressing the rate of significant Gleason sum upgrading, defined as a Gleason sum increase either from < or = 6 to > or = 7 or from 7 to > or = 8 between the biopsy and RP specimens. Regression coefficients were used to develop and validate (200 bootstrap re-samples) a nomogram predicting significant biopsy Gleason sum upgrading. RESULTS: Significant biopsy Gleason sum upgrading was recorded in 1349 (28.2%) patients. In multivariate LRMs, all predictors were highly significant (all P < 0.001). The bootstrap-corrected accuracy of the nomogram predicting the probability of significant Gleason sum upgrading between biopsy and RP specimens was 75.7%. CONCLUSION: Our nomogram might prove highly useful when the possibility of a more aggressive Gleason variant could change the treatment options.  相似文献   
995.
New therapeutic concepts of cell and tissue replacement therapies have been introduced in treatment of neurological disorders which require robust and sensitive sensomotoric behavioral diagnostic test systems for experimental research. However, most test arrays available are either expensive and/or sensitive to environmental disturbances. Moreover, an extensive training phase for experimental animals is often required by conventional tests to get reproducible data. In this study, we describe a new test array, the Stairway, that is robust, cost-effective, and needs only a minimum training phase. Its efficiency is evaluated in comparison to the well-established RotaRod and modified neurological severity score. Stroke was induced by middle cerebral artery occlusion. Human umbilical cord blood transplantation (n = 18) was performed 24 h after stroke by intravenous injection of suspended cells in comparison to control injections (n = 18), while behavioral assessment was carried out continuously for 29 days. Furthermore, development of lesions was monitored by magnetic resonance imaging. The results reveal the Stairway test as a simple, highly reproducible, and easy manageable test system thus reflecting therapeutic benefits precisely.  相似文献   
996.
Extracorporeal human lymphatic organs are expected to be excellent tools in the study of human molecular and cellular bases of the immunologic balance and tissue harmony. A rational approach and process to design a device and a procedure to recreate the human lymph node environment in vitro is described with emphasis on T-cell activation. Based on this approach, a bioreactor and a process supporting self-assembly of human lymphatic tissues due to proper emulation of human architecture and homeostasis could be developed.  相似文献   
997.
The purpose of this retrospective study was to evaluate the clinical and radiological outcome of bilateral sacroiliac joint (SIJ) fusion, using a new technique, in patients with a chronic SIJ syndrome. Seventeen patients with chronic low back pain, with a positive response to specific diagnostic tests for the SIJ, were considered candidates for bilateral sacroiliac fusion. The surgical indication was based on the results of local anaesthetic joint infiltration, temporary external fixation or bone scan. Ten patients had had previous surgery on the lumbar spine. Bilateral posterior SIJ fusion was performed with internal fixation and decortication of the sacroiliac joint, using a separate approach to each joint. Local bone grafting was performed. At the time of follow-up (on average 39 months after surgery), 3 patients reported moderate or absent pain, 8 marked pain and 6 severe pain. Seven patients showed a symptomatic non-union; union occurred in only 6 cases. Eighteen percent of the patients were satisfied, but in the other 82% the results were not acceptable. Reoperation was performed in 65% of the patients. Our results with bilateral posterior SIJ fusion were disappointing, which may be related with difficulties in patient selection, as well as with surgical technique. Better diagnostic procedures and possibly other surgical techniques might provide more predictable results, but this remains to be demonstrated.  相似文献   
998.
PURPOSE: Preservation of sexual function is one of the main objectives in radical prostatectomy. We assessed possible predictive factors for postoperative sexual function including preoperative International Index of Erectile Function score, age and extent of nerve sparing procedures for more precise preoperative counseling of patients undergoing radical prostatectomy. MATERIALS AND METHODS: Between January 2000 and December 2001 a total of 694 patients with clinically organ confined prostate cancer underwent nerve sparing radical prostatectomy. Preoperative erectile function was assessed with the International Index of Erectile Function score. After at least 12 months of followup patients were asked to answer the International Index of Erectile Function and Quality of Life Questionnaire C 30 via mail. RESULTS: A total of 411 patients responded to the questionnaire, 122 of whom underwent unilateral nerve sparing radical prostatectomy and 289 underwent bilateral nerve sparing radical prostatectomy. Data on preoperative and postoperative International Index of Erectile Function scores were available for 389 patients. Data on the International Index of Erectile Function and the postoperative Quality of Life Questionnaire C 30 were available for 382 patients. The median decrease in International Index of Erectile Function score was 7 points. Patients undergoing unilateral nerve sparing radical prostatectomy had a significantly stronger decrease in International Index of Erectile Function score compared to patients undergoing the bilateral nerve sparing procedure (12 vs 6 points). Preoperative International Index of Erectile Function score and extent of nerve sparing (unilateral vs bilateral nerve sparing radical prostatectomy) were significantly associated with better postoperative sexual function whereas age was not. Based on preoperative International Index of Erectile Function score, surgical technique and age, the likelihood of postoperative satisfactory erectile function can be defined preoperatively. CONCLUSIONS: We confirmed the impact of the extent of nerve sparing (unilateral vs bilateral nerve sparing radical prostatectomy) and highlighted the effect of preoperative erectile function as measured by the International Index of Erectile Function and age at surgery on postoperative sexual function. Our data can be used for counseling patients undergoing radical nerve sparing prostatectomy regarding recovery of erectile function.  相似文献   
999.
Dural involvement in primary extradural meningiomas of the cranial vault   总被引:1,自引:0,他引:1  
OBJECT: The authors retrospectively analyzed a consecutive series of patients with cranial vault primary extradural meningioma (PEM), with particular regard to the tumor's dural involvement. The pertinent literature was reviewed. METHODS: Clinical data were retrospectively obtained in a consecutive series of 16 patients treated for a PEM at two institutions between 1992 and 2004. The authors created a classification system based on dural involvement of the tumors. Nine women and six men (mean age 55 years) presented with a painless, slowly progressive swelling. Preoperative magnetic resonance (MR) imaging revealed dural enhancement at the site of tumor in 11 patients. On surgical inspection, the tumor infiltrated the dura in all but three patients. Histological examination of tissue samples demonstrated tumor infiltration of the dura in all 14 patients in whom the dura had been resected. Three recurrent tumors were observed on follow-up examination during a mean period of 5.8 years (range 1.5-13 years) and required extirpation. In addition to one patient in whom there was histological evidence of malignancy, the other two cases involved two patients in whom no apparent dural involvement was observed during the first surgery. In a review of the literature, the authors found that histological examination showed dural involvement in 22%; the dura was not histologically evaluated in the remaining patients (78%). Postoperative follow-up data exceeding 2 years were only provided in two of the reported cases. CONCLUSIONS: Tumor infiltration of the dura should be assumed in PEMs of the cranial vault, and resection of the dura at the site of craniotomy is recommended to prevent tumor recurrence.  相似文献   
1000.
BACKGROUND: In kidney transplantation, preservation has a significant influence on organ function. Since previous reports have indicated a benefit of combining histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) solution, we evaluated the effects of initial flush with low viscosity HTK, followed by storage in UW. MATERIAL AND METHODS: Kidneys from inbred Lewis rats were procured using HTK or UW for initially perfusion and re-flushed after 30 min with either solution. In a third group, after perfusion with HTK, organs were re-flushed with UW. Organs were stored for 16-24 h (4 degrees C). Study parameters were high-energy phosphates, histology, apoptosis, recipient survival and urine excretion of 15-F2t -isoprostanes (oxidative stress marker). RESULTS: Prior to transplantation, tissue ATP/ADP concentrations were: HTK/UW > UW-only > HTK-only. In transplanted kidneys, histological damage was highest after preservation in HTK-only. Twenty-four hours after transplantation (24 h cold ischemia time - CIT), cleaved-PARP was most abundant using UW-only. 16 h of CIT resulted in higher urine concentrations of isoprostanes in the order HTK-only (368 +/- 308) > UW-only (157 +/- 105) > HTK/UW (67 +/- 26), and was lower in HTK/UW after 24 h of CIT (146 +/- 38) vs. UW-only (507 +/- 33 pg/mg creatinine). Survival (24 h CIT) was significantly reduced, and percentage of initial non-functioning (INF) kidneys highest in HTK-only (2.6 +/- 0.3 days, 100%), compared to UW-only (13 +/- 4.4 days, 75%) and HTK/UW (18.5 +/- 4.6 days, 33%). CONCLUSIONS: In long-term preservation, UW is superior over HTK. However, our results indicate that perfusion with HTK prior to storage in UW may improve the results of UW alone which is reflected by better survival, lower rate of INF, higher cellular energy conservation and a decrease of free radicals.  相似文献   
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