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Anderson NG Laurent I Cook N Woodward L Inder TE 《AJNR. American journal of neuroradiology》2005,26(10):2685-2690
BACKGROUND AND PURPOSE: It is desirable to develop a bedside method for assessing cerebral development in the very premature infant to monitor the effectiveness of interventions aimed at improving cerebral development. Our aim was to describe the growth trajectory of the corpus callosum (CC) on cranial sonography in very premature infants. METHODS: We recruited 100 very-low-birth-weight infants admitted to a single regional level III neonatal intensive care unit from November 1998 to November 2000. Cranial sonography images of the CC were obtained for 64 (32 boys) infants (mean gestational age, 28 weeks; range, 23-33 weeks) in the first week of life and at term equivalency. The growth rate of the CC was compared in the 64 study infants to the expected growth rate of 0.20-0.27 mm/day from antenatal data and correlated with clinical outcome at 2 years of age by using Mental Development Index (MDI) and Psychomotor Development Index (PDI). RESULTS: The average growth rate of the CC was half of that expected from antenatal data. Mean growth rates were similar for all gestational ages (mean, 0.11 mm/day; range, 0.05-0.29; P = .4). The CC at term equivalency was longer for those in MDI class 2 (mean, 44.3 mm) compared with MDI class 3 (mean 40.2 mm; P = .003) as well as for PDI class 2 versus 3 (P = .017). CONCLUSION: Measurement of the length of the CC at cranial sonography is reproducible. Those with poorer neurodevelopmental outcomes have a shorter CC at term equivalency. The CC grows at a much lower rate postnatally than in utero among very premature infants. 相似文献
85.
Francis JL Gleeson M Pyne DB Callister R Clancy RL 《Medicine and science in sports and exercise》2005,37(4):571-578
PURPOSE: This study examined the nature of the variability in salivary immunoglobulin and albumin concentrations within an individual, between individuals, and between populations with differing levels of habitual physical activity. METHODS: Fourteen elite swimmers, and 21 active and 18 sedentary individuals provided 12 saliva samples over a 30-d period. Group classifications were based on interviews, anthropometric measurements, and physical activity records. Symptoms of illness and physical activity data were recorded daily. Salivary IgA, IgG, and IgM were measured by ELISA, and albumin concentrations were measured by nephelometry. Variability was assessed using ANOVA procedures. RESULTS: Elite swimmers, compared with active and sedentary individuals, had higher concentrations of salivary IgA (geometric mean=65 vs 32 and 40 mg.L, P=0.002) and greater variability in salivary IgA concentrations as individuals (P=0.007) and as a group (P=0.03). Salivary IgG variability in swimmers was also twofold greater than the other two groups (P=0.008). Salivary IgM and albumin variability were not significantly different between groups, but individual variability differed for swimmers and active individuals. The intraclass correlations for salivary IgA and IgG (but not for IgM or albumin) were 50% lower for swimmers than the other two groups (ICC for IgA: 20% swimmers vs 54% active and 46% sedentary individuals; ICC for IgG: 36 vs 59 and 57%). CONCLUSION: The variability and fluctuation of salivary immunoglobulin concentrations were consistently greater in the elite swimmers, but multiple samples from individual swimmers were less correlated compared with participants with lower physical activity levels. These findings have implications for monitoring mucosal immune status within individuals and when comparing salivary immunoglobulin concentrations between groups with differing levels of physical fitness and activity. 相似文献
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Preliminary investigation into the effects of electrical stimulation on mandibular distraction osteogenesis in goats 总被引:3,自引:0,他引:3
El-Hakim IE Azim AM El-Hassan MF Maree SM 《International journal of oral and maxillofacial surgery》2004,33(1):42-47
Craniofacial distraction osteogenesis (DO) was found to be a procedure with low preoperative and postoperative morbidity. Direct current electrical stimulation is used clinically to treat different orthopaedic problems. It provided a significant increase in new-bone formation, and a higher mechanical strength of healing.The purpose of this study was to test the effect of electric current on distraction osteogenesis and to establish the best period to apply an electric current during the different distraction phases.Twelve healthy adult goats were subjected to a vertical osteotomy in the symphyseal area. A distraction device was fixed to the bone. Animals were divided into two groups, Group I (three goats) and group II (nine goats). In group I, the device was activated 1mm per day for 10 days; while in group II, the device was activated 1mm per day for 10 days with the application of direct electric current stimulation of 10 microA either during the first 3 days of latency in a continuous mode (ESL group), or during the first 3 days of the activation period in a continuous mode (ESA group); or during the first 3 days of the consolidation period in a continuous mode (ESC group). After the activation period was completed, the distraction device left in place for additional 15 days for bone consolidation in all animals. Animals were then sacrificed, the mandible was harvested, and the distracted areas were removed and processed for mechanical and histological studies. The results of this study suggested that direct current electrical stimulation display synergism on mandibular distraction when this stimulation applied to the distraction zone during activation or consolidation periods. 相似文献
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Anand I McMurray J Cohn JN Konstam MA Notter T Quitzau K Ruschitzka F Lüscher TF;EARTH investigators 《Lancet》2004,364(9431):347-354
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To understand alterations to the urokinase system that may occur in progressively metastatic prostate cancer cells, we assessed urokinase plasminogen activator receptor (uPAR) expression, in vitro motility towards vitronectin, urokinase plasminogen activator (uPA)-induced growth and growth factor regulation of uPAR expression in three cell lines—PC-3 and two derivatives from secondary metastases, PC-3M and PC-3MM2. DU-145 and Tsu-Pr1 cells were included for comparative purposes. uPAR expression increases with metastatic passage in these cell lines and accompanies increased growth and motility responses in the presence of uPA. Growth factors TGF1 and IGF-1 induce uPAR in all three prostate cancer lines; however, PC-3M and PC-3MM2 cells also respond to bFGF. Of the cell lines tested, PC-3MM2 most uniformly respond to added TGF1, IGF-1 and bFGF. These results show that in two progressive derivatives from repeated metastasis of PC-3 cells, constitutive and growth factor-induced uPAR expression is enhanced. This increased uPAR facilitates the properties of growth and motility. 相似文献
90.
Perkash I 《The journal of spinal cord medicine》2004,27(4):383-386
The foundation of the management of neurogenic bladder can be attributed to a pioneer in spinal cord injury medicine. Dr. Donald Munro, a neurosurgeon, who also had experience in urologic surgery, established the first Spinal Cord Injury Service of 10 beds in the Boston City hospital in the 1930s. He later became adviser to the US Army and the Veterans Administration (VA). On his recommendation, paraplegic centers were created in US army hospitals and later in the VA hospitals from 1943 to 1945. This article reviews the evolution of the management of neurogenic bladder in patients with spinal cord injuries from the past century to the present. The role of urodynamics in defining neurologic lesions is critical to the appropriate management of the voiding dysfunction. Key advances, such as the diagnosis of detrusor sphincter dyssynergia (DSD), recognition of its association with autonomic dysreflexia, and its definitive management, have been emphasized. The role of transrectal linear array sonography using a rectal probe was found useful for defining bladder outlet dysfunction during urodynamics. It also helped to recognize secondary bladder neck obstruction and diagnose false passages in the urethra. Clean technique intermittent catheterization (IC) was evaluated and recommended. In about 28% patients with DSD that led to secondary bladder neck obstruction, a consequence of IC was reported. Transurethral laser sphincterotomy (TURS) was first reported by me in 1991, and later, durable 7-year follow-up results were reported in 78% of the first 99 patients. We reported a surgical technique to lengthen the penis. We also reported the long-term success with semirigid implants in 92% of patients with SCI. This technique helped maintain external condom drainage on a small phallus and improved the sex life of patients, as well as their quality of life. The author's pertinent areas of interest in the past one-half century were aimed at recognizing specific urologic problems associated with neurologic impairment. Management was aimed at preventive care, early recognition, and timely management to reduce secondary complications and enhance quality of life. 相似文献