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BACKGROUND: Laparoscopically procured live donor kidney grafts are increasingly transplanted into pediatric recipients. The safety and efficacy of this changed surgical practice are unknown. HYPOTHESIS: Outcomes of laparoscopic vs open donor grafts in recipients 18 years and younger are equivalent. DESIGN AND SETTING: Retrospective review at an academic tertiary care referral center. PATIENTS: Eleven consecutive pediatric recipients of laparoscopically procured kidneys between April 1, 1997, and December 31, 2001, were pair matched for age with 11 recipients of openly procured kidneys between December 1, 1991, and March 31, 1997; the 22 adult donors were also studied. MAIN OUTCOME MEASURES: Recipients: surgical complications, graft function and survival. Donors: perioperative morbidity and length of hospital stay. RESULTS: Twenty (91%) of 22 kidneys were donated by a parent of the recipient. In recipients of laparoscopically procured grafts, we observed significantly lower creatinine clearances and higher creatinine levels on days 1, 4, and 6, but by 1 month, graft function was similar in both groups. No significant differences in surgical complications, delayed function, acute and chronic rejection, and graft survival rates were found. No laparoscopic or open donor required blood transfusion, reoperation, or hospital readmission. One laparoscopic donor (9%) was converted to open nephrectomy. For laparoscopic vs open donors, median operative time was longer (difference, 67 min; P =.08), but median postoperative length of stay was significantly shorter (3 vs 5 days; P =.02). CONCLUSIONS: Laparoscopic live donor nephrectomy has no adverse impact on pediatric recipient outcomes. For donors, the laparoscopic operation is safe and the hospital stay is shortened. These results support the continued use of laparoscopically procured live donor kidneys in pediatric renal transplantation.  相似文献   
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We sought to describe rates of kidney function decline and to identify modifiable risk factors for CKD progression in a multicenter prospective cohort study of adolescents with CKD aged 11 to 18 years seen semiannually for up to three years. Of the 23 subjects meeting inclusion criteria, the average estimated GFR was 51 ± 27 ml/min/1.73 m2 (0.85 ± 0.45 ml/s/1.73 m2) at entry. The overall annualized decline in GFR was 5.6 ml/min/1.73 m2 (0.093 ml/s/1.73 m2) per year (95% confidence interval [95% CI]: 1.9 to 9.3 [0.032 to 0.16]). The adjusted annualized decline in GFR was found to be accelerated in males, as well as among those over 15 years of age. The adjusted annualized decline in GFR was greater among those with either anemia (hematocrit below 36%), or hypoalbuminemia (albumin below 4 g/dl [40 g/L]). After adjustment, anemia was associated with an accelerated decline of 7.8 ml/min/1.73 m2 (0.13 ml/s/1.73 m2) (95% CI: 3.3 to 12 [0.055 to 0.20]) and hypoalbuminemia was associated with an accelerated decline of 17 ml/min/1.73 m2 (0.28 ml/s/1.73 m2) (95% CI: 11 to 22 [0.18 to 0.37]). Further study is needed to evaluate whether treatment of anemia or hypoalbuminemia, as outlined in current clinical care guidelines for CKD, may slow the progression of CKD in adolescents.  相似文献   
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L-DOPA is the most effective pharmacological agent used for the symptomatic treatment of Parkinson's disease but long-term L-DOPA treatment induces involuntary abnormal movements such as dyskinesias. The present study, using in vivo microdialysis, investigated the effects of a single or subchronic administration of L-DOPA to adult rats with a unilateral 6-OHDA lesion of dopamine neurons on GABA release in the substantia nigra, pars reticulata (SNr). The results indicate that a challenge injection of L-DOPA (50 mg/kg, i.p.) significantly increases GABA levels in the SNr of rats treated with a daily repeated administration of L-DOPA (50 mg/kg, i.p.). Further statistical analysis between groups also showed that extracellular GABA levels were significantly higher in the subchronic L-DOPA group than in the group receiving only one injection of L-DOPA. These results show that the subchronic administration of L-DOPA results in a sensitization of enhanced extracellular GABA levels in the SNr.  相似文献   
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BACKGROUND: Intraspinal meningiomas are less frequent in occurrence as compared with their intracranial counterparts. Typical presentation is onset of new spinal pain followed by other deficits in the sixth decade of life. Although total surgical removal is the optimum treatment, various tumor- and patient-related factors can determine the aggressiveness of the surgical endeavor. We present our experience of diagnosis and management of cervical intraspinal meningioma in the oldest reported patient (101 years) with an atypical clinical presentation and remarkable dissociation between clinical and radiologic findings. METHOD: The patient, a 101-year-old woman, experienced progressive weakness in her legs. Motor examination revealed no definite weakness. There was stocking type sensory loss to just below the knees bilaterally. The MRI of the cervical spine showed an enhancing mass anterolateral to the cord at the region C7 through T1. It markedly compressed the cord. RESULT: The tumor was removed in total, and the dural attachment was thoroughly coagulated. CONCLUSION: The presented experience supports the belief that, in spinal meningiomas, a good clinical outcome can be expected even in patients who may be less than perfect candidates for an aggressive surgical approach.  相似文献   
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OBJECTIVE: Visceral artery aneurysms may be treated by aneurysm exclusion, excision, revascularization, and endovascular techniques. The purpose of this study was to review the outcomes of the management of visceral artery aneurysms with catheter-based techniques. METHODS: Between 1997 and 2005, 90 patients were identified with a diagnosis of visceral artery aneurysm. This was inclusive of aneurysmal disease of the celiac axis, superior mesenteric artery (SMA), inferior mesenteric artery, and their branches. Surveillance without intervention occurred in 23 patients, and 19 patients underwent open aneurysm repair (4 ruptures). The endovascular treatment of 48 consecutive patients (mean age 58, 60% men) with 20 visceral artery aneurysms (VAA) and 28 visceral artery pseudoaneurysms (VAPA) was the basis for this study. Electronic and hardcopy medical records were reviewed for demographic data and clinical variables. Original computed tomography (CT) scans and fluoroscopic imaging were evaluated. RESULTS: The endovascular treatment of visceral artery aneurysms was technically successful in 98% of 48 procedures, consisting of 3 celiac axis repairs, 2 left gastric arteries, 1 SMA, 12 hepatic arteries, 20 splenic arteries, 7 gastroduodenal arteries, 1 middle colic artery, and 2 pancreaticoduodenal arteries. Of these, 29 (60%) were performed for symptomatic disease (5 ruptured aneurysms). Procedures were performed in the endovascular suite under local anesthesia with conscious sedation (94%). The femoral artery was used as the preferential access site (90%). Coil embolization was used for aneurysm exclusion in 96%. N-butyl-2-cyanoacrylate (glue) was used selectively (19%) using a triaxial system with a 3F microcatheter for persistent flow or multiple branches. The 30-day mortality was 8.3% (n = 4). One patient died from recurrent gastrointestinal bleeding after gastroduodenal embolization, and the remaining died of unrelated causes. All perioperative deaths occurred in patients requiring urgent or emergent intervention in the setting of hemodynamic instability. No patients undergoing elective intervention died in the periprocedural period. Postprocedural imaging was performed after 77% of interventions at a mean of 16 months. Complete exclusion of flow within the aneurysm sac occurred in 97% interventions with follow-up imaging, but coil and glue artifact complicated CT evaluation. Postembolization syndrome developed in three patients (6%) after splenic artery embolization. There was no evidence of hepatic insufficiency or bowel ischemia after either hepatic or mesenteric artery aneurysm treatment. Three patients required secondary interventions for persistent flow (n = 1) and recurrent bleeding from previously embolized aneurysms (n = 2). CONCLUSION: Visceral artery aneurysms and pseudoaneurysms can be successfully treated with endovascular means with low periprocedural morbidity; however, the urgent repair of these lesions is still associated with elevated mortality rates. Aneurysm exclusion can be accomplished with coil embolization and the selective use of N-butyl-2-cyanoacrylate. Current catheter-based techniques extend our ability to exclude visceral artery aneurysms, but imaging artifact hampers postoperative CT surveillance.  相似文献   
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Jennings  LK; Phillips  DR; Walker  WS 《Blood》1985,65(5):1112-1119
Hybridomas secreting monoclonal antibodies (MoAbs) to human platelet membrane glycoprotein IIb (GPIIb) were prepared by fusing cells of a mouse myeloma line to spleen cells from a BALB/c mouse immunized with purified GPIIb. Six of the hybridomas secreted MoAbs that recognized epitopes on the 23,000-dalton, disulfide-linked subunit of GPIIb, GPIIb beta. All six of these MoAbs agglutinated platelets in the absence of calcium. The agglutination titers of three of the MoAbs, however, were enhanced between 2 and 6 log2 dilutions when titrated in the presence of mmol/L of calcium. The enhancement in titer was the result of MoAb- induced platelet activation followed by platelet aggregation, a reaction that could also be initiated by the monovalent Fab fragments prepared from one of the MoAbs. The MoAbs did not significantly agglutinate platelets from patients with Glanzmann's thrombasthenia, confirming biochemical evidence that there is a paucity of GPIIb beta in the membranes of these cells. Our results show that MoAbs to epitopes on GPIIb beta initiate distinct platelet responses; therefore, they should be useful for studying the ways in which regions of surface glycoproteins are involved in platelet-platelet interactions. In addition, these reagents may prove of value in diagnosing and typing patients with Glanzmann's thrombasthenia.  相似文献   
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