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991.
BACKGROUND: Despite major surgical and medical advances, it is still a challenge to perform transplantation in small infants. This study, focusing on short- and long-term outcomes, summarizes our 10-year experience with liver transplantation (LTx) in infants aged less than 6 months. PATIENTS AND METHODS: We analyzed 43 patients aged 6 months or less (range: 12-184 days, median: 136 days) whose median weight at the time of LTx was 5.8 kg (range: 2.8-8.0 kg). The reasons for LTx were biliary atresia (n=27; 62.8%), neonatal hepatitis (n=6; 14%), neonatal cholestasis (n=4; 9.3%), and miscellaneous (n=6; 14%). The patients were followed up for a median time of 3 years and evaluated with respect to graft function, physical, and neurodevelopmental outcome. RESULTS: The patient survival was 90.7% after 1 year and 87.2% after 2 years. The graft survival was 86% after 1 year and 82.1% after 2 years. Twelve patients (27.9%) experienced 15 surgical complications requiring intervention, two of whom demonstrated vascular thrombosis (4.7%). Acute early rejection occurred in 15 patients (34.9%), and chronic rejection occurred in 3 patients (7%); 83.3% of the patients had normal liver function test results at the time of evaluation. Complications such as posttransplant lymphoproliferative disease (4.7%) and persistent arterial hypertension (4.7%) were rarely seen. The physical and neurodevelopmental outcomes were good. CONCLUSIONS: LTx in infants aged less than 6 months provides excellent short- and long-term results. Low weight or young age of infants awaiting LTx should not be exclusion criteria for LTx.  相似文献   
992.
OBJECTIVE: Circulating 8-iso-prostaglandin F 2alpha (8-iso-PGF 2alpha ) has been proposed as new indicator of oxidative stress, which is involved in the pathophysiologic changes of atherosclerosis. We proposed to test the hypothesis that 8-iso-PGF 2alpha is an independent predictor of symptomatic peripheral arterial disease (PAD). METHODS: A case-control study in 100 patients with symptomatic PAD and 100 control subjects matched for age, sex, and diabetes mellitus was conducted. Smokers and subjects using lipid-lowering drugs were excluded. Serum total 8-iso-PGF 2alpha was quantified with an enzyme immunoassay. RESULTS: Median 8-iso-PGF 2alpha was higher in patients with PAD than in control subjects (63 vs 42 pg/mL; P = .001). Logistic regression with hypertension, body mass index, and creatinine, low-density lipoprotein (LDL) cholesterol, triglyceride, high-sensitivity C-reactive protein (hs-CRP), 8-iso-PGF 2alpha , and total homocysteine concentrations as independent variables and case-control status as dependent variable revealed significant odds ratios (OR) for hypertension (OR, 3.74; 95% confidence interval [CI], 1.85-7.53), low-density lipoprotein cholesterol (OR, 1.16, for an increment of 10 mg/dL; 95% CI, 1.07-1.27), high-sensitivity C-reactive protein (OR, 1.02, for an increment of 1 mg/L; 95% CI, 1.00-1.03), and 8-iso-PGF 2alpha (OR, 1.11, for an increment of 10 pg/mL; 95% CI, 1.03-1.20). CONCLUSIONS: Serum total 8-iso-PGF 2alpha was an independent predictor of PAD in the population studied. This finding supports the hypothesis that 8-iso-PGF 2alpha is a risk marker for PAD. Our results indicate increased systemic oxidative stress in patients with PAD.  相似文献   
993.
PURPOSE: This ongoing randomized study aims to find out whether transurethral holmium laser enucleation of the prostate (HoLEP) could be an alternative to open transvesical prostatectomy in patients with prostates >100 g. PATIENTS AND METHODS: A series of 120 urodynamically obstructed patients were randomized to HoLEP or open prostatectomy, 60 patients to each group. The HoLEP was performed with high-powered Ho:YAG lasers at 80 to 100 W (2.0 J, 40-50 Hz) and 550-nm bare laser fibers. The American Urological Association Symptom Scores, peak urinary flow rates, and postvoiding residual urine volumes were evaluated preoperatively and at 1, 3, 6, 12, and 18 months postoperatively. All complications were noted. RESULTS: By the Mann-Whitney test, there was no significant difference between the HoLEP and open surgery groups in patient age (69.0 years HoLEP v 71.0 years open surgery), prostate volume (115 cc [range 100-230 cc] v 113 cc [100-230 cc], or weight of resected tissue (94 g [range 57-220 g] v 96 g [range 61-220 g]). There were significant differences in the mean operative time (136 v 91 minutes; P< 0.0001), mean hemoglobin loss (1.9 v 2.8 g/dL; P< 0.0001), median catheter time (1 day v 6 days; P< 0.0001), and median hospital stay (2 days v 10 days; P< 0.0001). Both HoLEP and open prostatectomy resulted in pronounced and lasting postoperative improvements in Symptom Scores, peak urinary flow rates, and postvoiding residual volumes (P< 0.0001). The differences between HoLEP and open prostatectomy were not significant at any interval for any parameter. Blood transfusions were required in 0 HoLEP patients v 8 open surgery patients. Arterial bleeding occurred in three patients in each group. Secondary apical resection was required in two HoLEP patients and no open surgery patients. Bladder neck contracture occurred in none of the HoLEP patients and two of those having open surgery. Thus, the total number of patients having complications was 7 with HoLEP and 13 with open surgery. There were no deaths in either group. CONCLUSIONS: The HoLEP appears to be an endourologic alternative to open surgical enucleation of the prostate for large glands. It entails significantly less blood loss and a much shorter catheter time and hospital stay. The perioperative outcome strongly favors the holmium procedure. The rate of late complications is equally low with each procedure. The postoperative micturition improvement was significant and lasting and was equivalent in the two groups.  相似文献   
994.
An 11-year-old boy with recurrent nephritis due to tubulointerstitial nephritis associated with uveitis (TINU syndrome) was treated with cyclosporin A (CSA) to induce sustained remission. CSA was introduced as a steroid-sparing drug because of extreme obesity (body mass index 32 kg/m2). Although the boy did not complain of any clinical symptoms, eye inspection after 7 months revealed bilateral disk edema with retinal bleeding and the patient developed cerebrospinal hypertension. Pseudotumor cerebri was diagnosed by measuring the intracranial pressure (31 cmH2O) and normal computer tomography and brain magnetic resonance imaging. Cessation of CSA therapy and treatment with mycophenolate mofetil led to resolution within 12 weeks.Supported by Forschungsunterstützungskreis Kindernephrologie e.V. Essen  相似文献   
995.
STUDY OBJECTIVE: To show that efficiency of operating room times can be improved significantly using rapid changes between operative procedures. DESIGN: Randomized, prospective clinical study. SETTING: Tertiary care university hospital, elective peripheral trauma-related orthopedic surgery. PATIENTS: 72 adult, ASA physical status I, II, and III patients scheduled for elective peripheral trauma-related orthopedic surgery requiring general anesthesia. INTERVENTIONS: Patient airways were managed using either a Laryngeal Mask Airway (LMA) or an endotracheal tube (ETT) in the hands of anesthesiologists experienced in both. They were not informed as to the primary intention of the study. All perioperative data, including the preoperative and postoperative outpatient stay at the outpatient surgical ward, were recorded with an anesthesia information management system. MEASUREMENTS: The primary outcome measures were: time needed for anesthesia induction and emergence from anesthesia. All manual recording into the anesthesia information management system during anesthesia was accomplished by nurses who were uninformed as to the aim of the study. MAIN RESULTS: Anesthesia induction was significantly (p < 0.01) shorter using LMAs (means +/- SD, medians, [interquartile ranges]) (LMA: 5.8 +/- 1.5, 5, [5;7] vs. ETT: 7.4 +/- 1.8, 7, [7;8] min), whereas emergence from anesthesia was not different (LMA: 11.8 +/- 3.3, 11, [9;14] vs. ETT: 13.2 +/- 4.8; 12, [10;16] min). CONCLUSION: The clinical relevance of reduced anesthesia induction time using LMA is questionable. The lack of difference in emergence time could be a result of the use of total intravenous anesthesia.  相似文献   
996.
Nephrotic syndrome (NS) represents the association of proteinuria, hypoalbuminemia, edema, and hyperlipidemia. Steroid-resistant NS (SRNS) is defined by primary resistance to standard steroid therapy. It remains one of the most intractable causes of ESRD in the first two decades of life. Mutations in the NPHS2 gene represent a frequent cause of SRNS, occurring in approximately 20 to 30% of sporadic cases of SRNS. On the basis of a very small number of patients, it was suspected that children with homozygous or compound heterozygous mutations in NPHS2 might exhibit primary steroid resistance and a decreased risk of FSGS recurrence after kidney transplantation. To test this hypothesis, NPHS2 mutational analysis was performed with direct sequencing for 190 patients with SRNS from 165 different families and, as a control sample, 124 patients with steroid-sensitive NS from 120 families. Homozygous or compound heterozygous mutations in NPHS2 were detected for 43 of 165 SRNS families (26%). Conversely, no homozygous or compound heterozygous mutations in NPHS2 were observed for the 120 steroid-sensitive NS families. Recurrence of FSGS in a renal transplant was noted for seven of 20 patients with SRNS (35%) without NPHS2 mutations, whereas it occurred for only two of 24 patients with SRNS (8%) with homozygous or compound heterozygous mutations in NPHS2. None of 29 patients with homozygous or compound heterozygous mutations in NPHS2 who were treated with cyclosporine A or cyclophosphamide demonstrated complete remission of NS. It was concluded that patients with SRNS with homozygous or compound heterozygous mutations in NPHS2 do not respond to standard steroid treatment and have a reduced risk for recurrence of FSGS in a renal transplant. Because these findings might affect the treatment plan for childhood SRNS, it might be advisable to perform mutational analysis of NPHS2, if the patient consents, in parallel with the start of the first course of standard steroid therapy.  相似文献   
997.
998.
999.
The Ki-67 protein has an essential role in cell proliferation. It is present in all dividing cells of normal and tumor tissues, but absent in resting cells. At present, no data are available about any alterations in the gene of this protein that could contribute to its altered structure and function, resulting in tumor development. We therefore searched for mutations in the Ki-67 gene (MKI67). cDNAs from four tumor cell lines derived from carcinoma of the cervix (HeLa), colon (CXF94, SW480), and lung (A549) were prepared. Defined parts of the cDNA were amplified by specific primers, cloned into pCRII-Blunt-TOPO vector, and replicated in Escherichia coli. The sequence of the amplified products were determined by automated fluorescence sequencing. Eight different mutations were characterized in the four cell lines tested. One is a deletion of a single base at position 1496 causing a truncated protein, the second is a A433T exchange is a silent mutation, and the remaining six mutations result in an amino acid change that might alter the conformation of the protein. Our results show that several mutations exist within the Ki-67 protein's cDNA in four tumor cell lines. These mutations might provide a genetic basis for tumor development.  相似文献   
1000.
Novel high-resolution temperature probe for radiofrequency dosimetry   总被引:1,自引:0,他引:1  
A novel integrated thermistor probe for temperature evaluations in radiofrequency-heated environments was realized. The probe's sensitive area is based on a highly resistive 50 microm x 100 microm layer of amorphous germanium processed on a glass tip. The small dimensions allow measurements with a distance as close as 150 microm from solid boundaries. Due to its high temperature resolution of 4 mK and its short response time of the order of 10 ms, the sensor is very well suited for dosimetric measurements in strong absorption gradients. The influence of radiofrequency (RF) electric fields on the signal is minimized due to the high resistance of the sensor and the leads. The probe was successfully used to determine the highly nonuniform absorption distribution resulting from the RF exposure of cell cultures placed in Petri dishes.  相似文献   
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