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71.
In two males, 11 and 12 years of age, referred for attention-deficit-hyperactivity disorder (ADHD), 47,XYY syndrome was diagnosed. A team that included a neuropsychologist, a physiotherapist, and a physician examined them. Stature (patients were above 97.5% height for age), muscle consistency, and tremor indicated chromosome analysis. Psychological tests results did not fully fit the ADHD diagnosis. On the basis of our clinical observation we felt that stimulant medication was indicated. Administration of methylphenidate led to improved motor and cognitive functions as well as social adaptation in both patients. We suggest that this treatment might well be considered in clinically similar patients with XYY sex chromosomes; we further suggest that learning problems in such individuals may be related to ADHD.  相似文献   
72.
Resuscitation with 100% O2 increases cerebral injury in hypoxemic piglets   总被引:5,自引:0,他引:5  
Perinatal asphyxia is a major cause of immediate and postponed brain injury in the newborn. We hypothesized that resuscitation with 100% O2 compared with ambient air is detrimental to the cerebral tissue. We assessed cerebral injury in newborn piglets that underwent global hypoxia and subsequent resuscitation with 21 or 100% O2 by extracellular glycerol, matrix metalloproteinase (MMP) expression levels, and oxidative stress. Extracellular glycerol was sampled by cerebral microdialysis. MMP levels were analyzed in cerebral tissue by gelatin zymography, broad matrix degrading capacity, and real-time PCR. Total endogenous antioxidant capacity was measured by the oxygen radical absorbance capacity assay. Extracellular glycerol increased 50% after resuscitation with 100% O2 compared with 21% O2. Total MMP activity was doubled in resuscitated animals at endpoint compared with baseline (p=0.018), and the MMP-2 activity was significantly increased in piglets that were resuscitated with 21% O(2) (p=0.003) and 100% O2 (p=0.001) compared with baseline. MMP-2 mRNA level was 100% increased in piglets that were resuscitated with 100% O2 as compared with 21% O2 (p < 0.05). Oxygen radical absorbance capacity values in piglets that were resuscitated with 100% O2 were considerably reduced compared with both baseline (p=0.001) and piglets that were resuscitated with 21% O2 (p=0.001). In conclusion, our data show increased MMP-2 activity at both gene and protein levels, accompanied with cerebral leakage of glycerol, presumably triggered by augmented oxidative stress. Our findings suggest that resuscitation of asphyxiated piglets with 100% O2 is detrimental to the piglet brain compared with resuscitation with 21% O2.  相似文献   
73.
Bladder exstrophy is a rare condition associated with lifelong issues including infection,renal insufficiency, incontinence, and fertility. Despite its seriousness, many affected children lead normal lives. With new operative techniques, children require fewer surgeries and have more hope for continence.With close follow-up, no child should develop renal insufficiency. Families should be reassured that a normal life and parenthood with normal sexual function are possible.  相似文献   
74.
OBJECTIVES: To evaluate the impact on photostimulable phosphor (PSP) image signal-to-noise ratio (SNR) of pre-scanning ambient lighting exposures. METHOD: PSP imaging plates (IPs) were exposed to different radiation exposures to achieve flat field images. The exposed IPs were subjected variously to visible light of different intensities (300, 150 or 20 lux) for durations ranging from < 10 s to 120 s. They were processed using laser scanners from two systems for further comparison (DenOptix versus ScanX). Histogram analysis was performed in each case and mean pixel value and its standard deviation were used as surrogates to assess SNR. Statistical methods applied included analysis of variance with Tukey honestly significant difference test for pair wise comparisons. The a priori alpha was set at P < or = 0.05. RESULTS: SNR decreased with increased duration and intensity of pre-scanning light exposure. Lower X-ray exposures resulted in decreased signal resulting in reduced SNR, and increased the need to reduce ambient lighting. No statistically significant differences were found comparing ScanX and DenOptix digital imaging systems in terms of SNR. CONCLUSION: Reduced ambient lighting is preferred for handling IPs prior to processing in the laser scanner.  相似文献   
75.
Nance ML  Lutz N  Carr MC  Canning DA  Stafford PW 《The Journal of trauma》2004,57(3):474-8; discussion 478
BACKGROUND: Nonoperative management of radiographically defined solid organ injuries has proven highly successful in children with blunt splenic and hepatic injuries. The role of nonoperative management protocols is less well defined for blunt renal injuries. The purpose of this study was to review the management and outcome of a consecutive series of children with blunt renal injury. METHODS: The trauma registry from a Level I pediatric trauma center was reviewed to identify all children (age < 19 years) who were treated for a blunt renal injury for the period January 1995 through December 2002. Demographic, anatomic, physiologic, management, and outcome data were analyzed. RESULTS: For the 8 years of review, 101 children with a blunt renal injury were identified, including 95 with accessible and complete data. The renal injury population had a mean age of 10.4 years (range, 0.5-18 years) and was 72.6% male. The renal injuries were distributed as follows: grade 1, n = 22; grade 2, n = 40; grade 3, n = 20; grade 4, n = 11; and grade 5, n = 2. Hematuria was present in 88.1% of children (in whom urinalysis results were available). Four children had underlying congenital renal anomalies. The mean hospital length of stay and intensive care unit stay were 6.0 and 2.6 days, respectively. Overall, 5 children (5.3%) required laparotomy, including 1 nephrectomy (isolated grade 4 injury) and 1 renorrhaphy, for an overall renal salvage rate of 98.9%. In children with isolated renal injuries (n = 48), one child (2.1%) required laparotomy. Seven children required adjunctive urologic procedures (ureteral stenting, n = 5; cystoscopy/cystogram, n = 2). There were seven deaths (7.4% overall; five because of head injury and two because of severe abdominal bleeding at presentation). CONCLUSION: A nonoperative management strategy was advantageous and successful in pediatric blunt renal injuries (94.7% successful nonoperative rate, 98.9% renal salvage rate). Adjunctive urologic procedures (e.g., ureteral stenting) were beneficial in selected cases.  相似文献   
76.
77.
Adherence of microorganisms, such as Candida albicans, represents the initial step in the establishment of infection and, accordingly, modification of this step represents a method by which the incidence of infection may be reduced. Therefore, this study uniquely examined the effects of polymeric nanoparticles on the adherence of blastospores of C. albicans to human buccal epithelial cells (BEC) in vitro. Poly(propylcyanoacrylate) nanoparticles were produced by emulsion polymerisation using a range of anionic, cationic and non-ionic surfactants, their particle size and zeta potential characterised and incubated with stationary phase blastospores of C. albicans for a defined period. Following this, the surface properties and size of blastospores with adsorbed nanoparticles were characterised. phosphate buffered saline-treated and nanoparticle-treated blastospores were incubated with human BEC for 2 h, following which the number of adherent blastospores was enumerated by light microscopy. The size and zeta potential of the nanoparticles were dependent on the surfactant employed in the manufacture process. Following nanoparticle adsorption, alteration of the zeta potential and an increase in the diameter of blastospores were observed. However, as this increase in diameter was indirectly related to the size of the nanoparticles, this may indicate a preference for the adsorption of smaller particles. In addition, following nanoparticle adsorption, the cell surface hydrophobicity (CSH) of C. albicans blastospores was increased and, importantly, the subsequent adherence to BEC in vitro was reduced. Most notably, the adherence of blastospores that had been treated with nanoparticles (stabilised with docusate sodium) was circa 73% lower than that of untreated blastospores. A moderate correlation between increased CSH and reduced adherence and a low correlation between blastospore zeta potential and adherence were observed, inferring that other mechanisms, most likely stearic hindrance, are responsible for the antiadherent properties of adsorbed nanoparticles. In light of their ability to reduce candidal adherence to BEC, it is suggested that polymeric nanoparticles may be useful in the prophylaxis of candidosis of the oral cavity.  相似文献   
78.
79.
The purpose of this study was to test the ability of students in scoring an observational tool for measuring physical disability, the Motor Assessment Scale (MAS) for stroke, before and after training in order to establish whether current training and testing procedures for students are adequate. Sixteen students were tested using items 1-8 of the MAS before and after training. The students were required to observe the videotaped performance of four patients with stroke being assessed using the MAS and to score the performance of each patient. After training, the students were retested. The percent exact agreement between students' scores and criterion scores was calculated for each student and for each item. They were then compared before and after training using Student t test. When compared with criterion, the students achieved a mean of 79.6% (standard deviation, 10.8%) exact agreement before training and 83.9% (standard deviation, 6.7%) after training. While this increase in percent exact agreement was not statistically significant (p = 0.10), all students reached at least 75% exact agreement after training. Percent exact agreement on the items increased significantly (p = 0.03) so that seven of the eight items reached at least 75% exact agreement after training. The results of this study suggest that training is important to ensure that all students reach an acceptable standard.  相似文献   
80.
PURPOSE: To compare the results of deep sclerectomy in capsular glaucoma (CG) with those in primary open-angle glaucoma (POAG). METHODS: This consecutive, prospective study comprised 24 CG patients (28 eyes) and 25 POAG patients (29 eyes) who underwent deep sclerectomy. Two different implants were used: either an absorbable collagen implant (Aqua-Flow) or a non-absorbable hydrophilic acrylic implant (T-Flux). The number of glaucoma medications, intraocular pressure (IOP) and complications were compared postoperatively. The definition of complete success was IOP below 19 mmHg without therapy. RESULTS: After a mean follow-up of 19.9 +/- 10.9 months (range 6-36 months) in the CG group and 16.2 +/- 10.0 months (range 6-36 months) in the POAG group, complete success was seen in 60.7% and in 37.9% of eyes, respectively (p=0.085). After adjustments for disparities in baseline characteristics, survival analysis demonstrated that success rates were better over time in CG eyes than in POAG eyes (p=0.038). At all time-points, except at 24 months, the IOP was lower in the CG group than in the POAG group. This difference was statistically significant at 1 week (p=0.050) and 3 months (p=0.006). At 18 months, the mean decrease in number of medications was 77.3% in the CG group and 65.9% in the POAG group (not statistically significant). Levelled hyphema occurred more frequently in CG eyes (35.7%) than in POAG eyes (13.8%). CONCLUSION: Capsular glaucoma patients had significantly higher success rates over time than POAG patients following deep sclerectomy with implant.  相似文献   
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