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31.
Human non-polio enterovirus (EV) is the most important cause of aseptic meningitis in children. Only a few studies report the lack of cerobrospinal fluid (CSF) pleocytosis in children with confirmed EV meningitis; however, the characteristics of these children have not been well defined. This paper describes the clinical and laboratory features of EV meningitis in children with no CSF pleocytosis. Clinical, laboratory, and virological data of Dutch patients <16 years diagnosed with EV meningitis, between 2003 and 2008, were analyzed retrospectively. Data of children with and without CSF pleocytosis were compared. A total of 149 children were infected with EV. Patients presented mainly with fever (n = 113), malaise (n = 43), abdominal pain (n = 47), and irritability (n = 61). Of the 60 patients with EV meningitis, 23 had no pleocytosis. Those who lacked CSF pleocytosis were younger [odds ratio (OR) 1.00; 95% confidence interval (CI) 1.000–1.002; p = 0.001], had experienced drowsiness more (OR 9.60; 95% CI 2.24–41.15; p = 0.002), had lower white blood cell counts (OR 0.73; 95% CI 0.61–0.89; p = 0.001), and had higher C-reactive protein (OR 1.13; 95% CI 1.03–1.23; p = 0.006) than those with pleocytosis. Conclusion. These findings show that EV meningitis occurs in the absence of CSF pleocytosis, particularly in young infants, meaning that EV meningitis in this age group cannot be solely excluded by the absence of CSF pleocytosis. They also confirm the importance of genome detection in the diagnosis of EV meningitis in young infants.  相似文献   
32.
基于物体空间序法的CT图像三维重建算法的研究   总被引:5,自引:0,他引:5  
首先对三维可视化方法进行了分类概述。接着对基本的物体空间序法及其改进算法——抛雪球法做了详细的描述,并且通过对两组CT数据进行三维重建实验,得到高质量的重构图像。最后,本文研究并采用了提取表面体素进行体绘制加速的方法,实现了基于等值面提取表面的加速算法,实验证明加速算法能够满足显示要求并能起到明显的加速作用。  相似文献   
33.
During a double-blind placebo-controlled study, the effect of cloxacillin prophylaxis in craniotomies on samples taken for culture from 334 operation wounds in 279 patients was assessed. Patients and operations were equally divided over the cloxacillin and placebo groups. In the cloxacillin group significantly fewer samples contained microorganisms than was the case in the placebo group both just after the incision was made (p less than 0.05) and just before closure of the wound (p less than 0.001). The contaminating bacteria found most frequently were Propionibacterium acnes and Staphylococcus epidermidis. For material collected immediately after the incision, the percentage of cultures positive for S. epidermidis was significantly (p = 0.001) lower in the cloxacillin group than in the placebo group; the percentage of cultures with P. acnes did not differ between the two groups. For samples taken just before the wound was closed, the percentage of cultures with P. acnes or S. epidermidis was significantly (p = 0.008 and 0.003, respectively) lower in the cloxacillin than in the placebo group. In the placebo group neurosurgical infections occurred with P. acnes and/or S. epidermidis as causative microorganisms; in almost all cases those bacteria could be cultured from the edge of the wound. In none of the patients with an infection caused by S. aureus was the bacteria found in the operation area. In 2/6 infections in the cloxacillin group the infecting microorganisms could be cultured from the operation area. These findings support a significant reduction in the infection rate after craniotomy under cloxacillin prophylaxis compared with placebo.  相似文献   
34.

Purpose

To test the hypotheses that (i) heavier rats demonstrate improved survival with diminished fibrosis in a diethylnitrosamine (DEN)-induced model of hepatocellular carcinoma (HCC) and (ii) transarterial embolization via femoral artery access decreases procedure times versus carotid access.

Materials and Methods

One hundred thirty-eight male Wistar rats ingested 0.01% DEN in water ad libitum for 12 weeks. T2-weighted magnetic resonance imaging was used for tumor surveillance. Rats underwent selective embolization of ≥ 5 mm tumors via carotid or femoral artery catheterization under fluoroscopic guidance. Rats were retrospectively categorized into 3 groups by initial weight (< 300, 300–400, > 400 g) for analyses of survival, tumor latency, and fibrosis. Access site was compared relative to procedural success, mortality, and time.

Results

No significant differences in tumor latency were related to weight group (P = .310). Rats weighing < 300 g had shorter survival than both heavier groups (mean, 88 vs 108 d; P < .0001), and more severe fibrosis (< 300 g median, 4.0; 300–400 g median, 1.5; > 400 g median, 1.0; P = .015). No significant difference was found in periprocedural mortality based on access site; however, procedure times were shorter via femoral approach (mean, 71 ± 23 vs 127 ± 24 min; P < .0001).

Conclusions

Greater initial body weight resulted in improved survival without prolonged tumor latency for rats with DEN-induced HCCs and was associated with less severe fibrosis. A femoral approach for embolization resulted in decreased procedure time. These modifications provide a translational animal model of HCC and transarterial embolization that may be suited for short-term survival studies.  相似文献   
35.
36.
Living donor liver transplantation (LDLT) demands a careful assessment of abnormal findings discovered during the evaluation process to determine if there will be any potential risks to the donor or recipient. Varying degrees of elevated hepatic iron levels are not uncommonly seen in otherwise healthy individuals. We questioned whether mild expression of hemosiderin deposition presents a safety concern when considering outcomes of living donation for both the donor and the recipient. We report on three LDLT patients who were found to have low‐ to moderate‐grade hemosiderin deposition on liver biopsy. All other aspects of their evaluation proved satisfactory, and the decision was made to proceed with donation. There were no significant complications in the donors, and all demonstrated complete normalization of liver function postoperatively, with appropriate parenchymal regeneration. The recipients also had unremarkable postoperative recovery. We conclude that these individuals can be considered as potential donors after careful evaluation.  相似文献   
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Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg­1 IV. and also atropine 0.05 mg kg­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.  相似文献   
40.
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