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71.
In this paper, we reviewed all existing studies using electroencephalography (EEG) in infants and children with known prenatal exposure to alcohol (PEA). The guiding purposes of the review were to determine if (1) EEG is a useful neuroimaging technique for investigating the brain correlates of PEA in infants and children, (2) there are indeed consistent EEG correlates of PEA in literature, and (3) these EEG correlates can be framed within a coherent picture of emerging implications for the study of PEA and its effects. The review confirms that EEG techniques have proven useful in indicating evidence of differential effects of patterns of PEA and timing in early fetal development and impairment of brain maturation in older children. In general, these techniques could be important in functional assessment of the brain of children affected by PEA, especially if used in conjunction with other neuroimaging techniques. The reviewed studies also suggest that although the impact on sensory and cognitive functions may involve extensive neural networks, there are EEG correlates of PEA which may in the future lead to the identification of neurophysiologic markers. A consistent aspect that emerges from the EEG data is that converging evidence from the study of different systems and processes suggests that PEA may almost invariably have consequences for later neurocognitive development.  相似文献   
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OBJECTIVE: To describe the dieting histories of bariatric surgery candidates. RESEARCH METHODS AND PROCEDURES: One hundred seventy-seven individuals with extreme obesity who sought bariatric surgery completed the Weight and Lifestyle Inventory, a self-report instrument that assesses several variables, including weight and dieting history. Patients' dieting histories were further explored with an aided recall during a preoperative behavioral/psychological evaluation performed by a mental health professional. RESULTS: Participants who completed the Weight and Lifestyle Inventory reported an average of 4.7 +/- 2.9 successful dieting attempts, defined as those that resulted in a loss of 10 lbs (4.5 kg) or more. These individuals reported a mean total lifetime weight loss of 61.1 +/- 41.3 kg. Despite these efforts, their weight increased from 89.4 +/- 27.4 kg at the time of their first diet (age 21.2 +/- 10.1 years) to 144.5 +/- 30.8 kg at the time they underwent their behavioral/psychological evaluation (age 43.0 +/- 11.0 years). Results of the aided recall revealed that participants had made numerous other efforts to lose weight that were unsuccessful. Self-directed diets and commercial programs were used more frequently. DISCUSSION: Individuals who sought bariatric surgery reported an extensive history of dieting, beginning in adolescence, that was not successful in halting progressive weight gain. Thus, the recommendation often made by insurance companies that patients delay surgery to attempt more conservative treatment options may be unwarranted, particularly in the presence of significant obesity-related comorbidities. Weight loss histories should be routinely examined during a behavioral evaluation to determine whether additional attempts at non-surgical weight loss are advisable. Future studies also are needed to explore the potential relationship between dieting history and postoperative outcome.  相似文献   
74.
Self-etching primers have recently been introduced to simplify the orthodontic bonding process. The aim of this study was to compare the effectiveness of such a product with conventional 2-stage etching and priming with 37% o-phosphoric acid and a conventional unfilled primer. Twenty consecutive patients having orthodontic bonds placed were selected to participate in this cross-mouth control study. Diagonally opposite quadrants were randomly allocated to either the self-etching primer group or the conventional etching and priming group. A total of 364 teeth were bonded with a light-cured diacrylate adhesive; bond failures were then monitored over 6 months. There were 20 bond failures (10.99%) in the self-etching primer group and 9 bond failures (4.95%) in the conventional etch and priming group over this period. The results were analyzed with the McNemar test and 95% confidence interval. The difference between the failure proportions was -0.06 with an associated 95% confidence interval of -0.121 to 0.001. This study produced weak evidence to suggest that bond failures with a self-etching primer will be higher than those with conventional etching and priming. This increased likelihood of bond failure must be weighed against the time advantage of the self-etching primer when used at the initial bonding appointment.  相似文献   
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Current treatment of acute stroke remains unsatisfactory. This review presents experimental and clinical data which suggest that mild induced hypothermia could be a potent and practicable neuroprotective treatment of acute ischaemic stroke and intracerebral haemorrhage. Hypothermia, if proven to be safe, effective and widely practicable in patients with acute stroke, could have an enormous positive impact on reducing the burden of stroke worldwide. Critical issues that will need to be considered in a well designed randomised controlled trial of induced hypothermia in acute stroke patients are discussed.  相似文献   
77.
The tibial attachments of the individual anteromedial (AM) and posterolateral (PL) fibre bundles and the entire attachment of the anterior cruciate ligament are described, relating them to consistent bony landmarks; 55 fresh-frozen specimens were measured. The fibre bundles were separated and excised at their attachments and their peripheries marked with a pen. High-resolution scaled digital photographs were taken of each dissected specimen and transferred onto a computer for analysis. A wide variation was found when using the posterior tibial axis, the anterior tibial surface and the medial tibial spine as reference points. The most consistent measurements used the tibial interspinous “over-the-back” ridge as a datum. The attachments of the PL and AM bundles were centred 10 ± 1 mm (mean ± SD) and 17 ± 2 mm anterior to the over-the-back ridge. They were 4 ± 1 and 5 ± 1 mm, respectively, lateral to the medial tibial spine border. The positions of 6 mm circles in the posterior-medial limits of the fibre bundles (representing tunnels in a double-tunnel reconstruction) were measured. The overall dimensions of the tibial plateaux correlated significantly with many measurements. The results from this study could be used to guide ACL reconstruction techniques.  相似文献   
78.
79.
Concern about short- and long-term ultraviolet radiation (particularly UVB) damage to the eye has led to increased research in this area. Numerous studies have confirmed the pathogenic enhancing roles of reflected ultraviolet (UV) and visible radiation in our environment. There is concern that conventional sunglasses do not protect the eye adequately from reflected rays (albedo), especially on the lateral aspect, from behind and from below. Using eye models and computer ray tracing methods, the pathways of oblique rays incident at the temporal peripheral cornea have been plotted by Maloof, Ho and Coroneo.1 These rays are refracted and focused and theoretically can result in up to 20 times the concentration of incident irradiance at the nasal anterior chamber angle and nasal equatorial cortex of the crystalline lens. The purpose of this study was to determine the limits of angular subtense of the incident peripheral light which is refracted in this manner in human subjects and to investigate the relation between corneal shape and certain ocular parameters to the limits. A statistically significant positive correlation was found between temporal entrance angle and anterior chamber depth (r = 0.70, P< 0.0006). The entrance angle ranged from 15 degrees to 30 degrees and was located 10 degrees to 45 degrees posterior to the coronal plane. Our results support Maloof and colleagues' predictions for the implication of focused peripheral UV and high intensity visible radiation in the pathogenesis of pterygium and cortical cataract and emphasise the need for lateral eye protection in conditions of high ultraviolet albedo.  相似文献   
80.
The mutational specificity of the syn dihydrodiol epoxide of 5-methylchrysene in the supF gene of the pSP189 vector was examined. Transversion mutations at GC pairs predominated with G → T and G → C changes accounting for 42 and 21% of total base change mutations. The types of mutations found reflect the previously determined chemical preference of this reactive species for reaction with deoxyguanosine residues in DNA.  相似文献   
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