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51.
BACKGROUND: The clinical significance of the 14 and 6 positive spikes (PS) electroencephalographic (EEG) phenomenon is not well established. This study was performed to provide further data regarding the clinical correlates of the PS, particularly attention-deficit/hyperactivity and somatic symptoms. METHODS: Diagnostic information gathered through structured interviews was compared among four groups of psychiatric inpatients aged 4-17 years who underwent an EEG examination over a 2-year period. Groups consisted of patients with: 1) 14 and 6 PS (n = 25); 2) epileptic discharges (n = 29); 3) slow-wave abnormalities (n = 23); and 4) a normal EEG group age and sex matched to the 14 and 6 PS group (n = 25). RESULTS: Attention-deficit hyperactivity disorder (ADHD) symptoms were significantly more frequent in the PS group (chi 2 = 2.96, p < .05) compared to the other three groups combined. Although somatic symptoms were not increased in the 14 and 6 PS group, anxiety symptoms tended to occur more in this group (chi 2 = 3.50, p < .06). CONCLUSIONS: The PS profile appears associated with ADHD symptoms. Possible treatment implications of this finding (e.g., use of anticonvulsants in ADHD patients with PS) need to be explored.  相似文献   
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Nitric oxide (NO) is an unusual chemical messenger. NO mediates blood vessel relaxation when produced by endothelial cells. When produced by macrophages, NO contributes to the cytotoxic function of these immune cells. NO also functions as a neurotransmitter and neuromodulator in the central and peripheral nervous systems. The effects on blood vessel tone and neuronal function form the basis for an important role of NO on neuroendocrine function and behavior. NO mediates hypothalamic portal blood flow and, thus, affects oxytocin and vasopression secretion; furthermore, NO mediates neuroendocrine function in the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes. NO influences several motivated behaviors including sexual, aggressive, and ingestive behaviors. Learning and memory are also influenced by NO. Taken together, NO is emerging as an important chemical mediator of neuroendocrine function and behavior.  相似文献   
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Describes a university 66-credit professional diploma sequence that includes 1 yr of internship experience for the training of school psychologists to work with bilingual/bicultural populations. Competence for working with these populations involves 3 general areas: language, cross-cultural expertise, and assessment. An integrated curriculum and faculty offers linguistics, cultural-urban studies, and bilingual education courses in addition to the core courses in professional school psychology. Bilingual students and faculty have been recruited. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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BACKGROUND AND PURPOSE: We investigated the frequency of cerebral microembolism detected by transcranial Doppler ultrasonography in patients with clinical evidence of retinal ischemia, including transient monocular blindness, central and branch retinal artery infarction, and ischemic oculopathy, and assessed its correlation with carotid artery stenosis. METHODS: Records of 331 consecutive patients examined during a 47-month period at the Neurovascular Laboratory were reviewed. Of the original 453 intracranial arteries, 186 middle cerebral arteries (MCAs) satisfied qualifying criteria that excluded patients with cardiac embolic sources. Forty-five MCAs ipsilateral to the symptomatic eye constituted the study group. The control group consisted of 141 asymptomatic MCAs. Microembolus detection studies were performed on transcranial Doppler instruments equipped with special software, and the degree of carotid artery stenosis was measured by cerebral or MR angiography or by color duplex studies. RESULTS: Microembolism was detected in 40.0% of study MCAs and 9.2% of controls (P < 0.001). In the study group, microembolic signals were detected in 61.9% of MCAs tested within a week of symptom onset and 20.8% of those tested afterward (P < 0.001). Severe (> or = 70%) carotid stenosis or occlusion was more frequent in the study group (P < 0.001). Microembolic signals were detected in 25.3% and 11.2%, respectively, of MCAs distal to carotid arteries with 70% to 100% and 0% to 69% stenosis (P = 0.013). CONCLUSIONS: In patients without cardiac embolic sources, cerebral microembolism is frequently present on the side of retinal ischemia, particularly during the week after onset of symptoms. It is often associated with severe stenosis or occlusion of the ipsilateral carotid artery.  相似文献   
55.
Differentiation inducers selected for their low cytotoxic and genotoxic potential could be of major value in chemoprevention and maintenance therapy. We focus here on phenylacetate, a naturally occurring plasma component recently shown to affect the growth and differentiation of established neoplasms in experimental models. The ability of phenylacetate to prevent carcinogenesis by the chemotherapeutic hypomethylating drug 5-aza-2'-deoxycytidine (5AzadC) was tested in vitro and in mice. Transient exposure of immortalized, but poorly tumorigenic ras-transformed 4C8 fibroblasts to 5AzadC resulted in neoplastic transformation manifested by loss of contact inhibition of growth, acquired invasiveness, and increased tumorigenicity in athymic mice. The latter was associated with elevation in ras expression and a decline in collagen biosynthesis. These profound phenotypic and molecular changes were prevented by a simultaneous treatment with phenylacetate. Protection from 5AzadC carcinogenesis by phenylacetate was: (a) highly efficient despite DNA hypomethylation by both drugs, (b) free of cytotoxic and genotoxic effects, (c) stable after treatment was discontinued, and (d) reproducible in vivo. Whereas athymic mice bearing 4C8 cells developed fibrosarcomas following a single i.p. injection with 5AzadC, tumor development was significantly inhibited by systemic treatment with nontoxic doses of phenylacetate. Phenylacetate and its precursor suitable for oral administration, phenylbutyrate, may thus represent a new class of chemopreventive agents, the efficacy and safety of which should be further evaluated.  相似文献   
56.
Therapeutic drug monitoring (TDM) is practiced for a number of frequently used drugs in infants and children. It is believed that monitoring drug levels will increase the probability of a therapeutic response and minimize the probability of adverse drug sequelae. Dose adjustments are based on measured drug levels interpreted relative to published therapeutic ranges which may or may not reflect the true relationship with either therapeutic or adverse effects. Potential errors derive from many sources, some amenable to solutions based on current knowledge, others awaiting improved understanding of the causes and consequences of unreliable therapeutic ranges.  相似文献   
57.
Experience with short tube decompressive jejunostomy in twenty-nine patients with small bowel obstruction is presented. Many advantages are gained by operative decompression of obstructed, dilated small bowel. The favorable results with its use make short tube decompressive jejunostomy a safe, acceptable method of decompressing dilated small bowel.  相似文献   
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Asperity scattering adds a 'surface lobe' to the usual diffuse, backscatter, and specular lobes of rough surfaces. Although rarely acknowledged, it is an important effect in many materials that are covered with a thin layer of sparse scatterers, such as dust or hairs. In common cases where single scattering predominates, asperity scattering adds important contributions to the structure of the occluding contour and the edge of the body shadow. This is because the bidirectional reflectance distribution function (BRDF) is inversely proportional to the cosines of both the illumination and viewing angles. The BRDF is generally low (and typically negligible) except when either the illuminating rays or visual directions graze the surface. Because asperity scattering selectively influences the edges in the image of an object, it has (as judged by photometric magnitudes) a disproportionally large effect on (human) visual appreciation. We identify it as a neglected but often decisive visual cue in the rendering of human skin. Its effect is to make smooth cheeks look 'velvety' or 'peachy', that is to say, soft (the appearances of both velvet and peachy skin are dominated by asperity scattering). This is a most important aesthetic and emotional factor that is lacking in Lambertian (looks merely dullish and paper-like), 'skin-type' BRDF (looks like glossy plastic), or even translucent (looks 'hard', vitreous) types of rendering.Published online: 8 August 2003  相似文献   
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