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91.
The distribution of neuropeptide Y (NPY)-like immunoreactivity was studied in the brain of the lizard Gallotia galloti, in order to gain insight into the comparative topography of this peptide. Antisera against both NPY and its C-terminal flanking peptide (C-PON) were used, demonstrating a general coexistence of both peptides, as described in other vertebrates. Most NPY-like immunoreactive (NPY-LI) cell bodies were observed in the telencephalon, specifically in various olfactory structures, all cortices, septum, basal ganglia (except for the globus pallidus), the nucleus of the diagonal band of Broca, the amygdaloid complex, and the bed nucleus of the anterior commissure. NPY-LI cells were also seen in the preoptic and hypothalamic regions and the dorsal thalamus (mainly in the perirotundal belt), as well as in the mesencephalic tegmentum (in the ventral tegmental area, the substantia nigra, and the retrorubral area). NPY-LI fibers and terminals were widely distributed in the brain. All visual and auditory neuropiles were densely innervated. Specially dense plexuses were seen in the nucleus accumbens, the ventral pallidum, the suprachiasmatic and ventromedial hypothalamic nuclei, the nucleus medialis thalami, the left habenula, and the central nucleus of the torus semicircularis. Our analysis shows that the distribution of NPY-like immunoreactivity in the forebrain of Gallotia largely resembles that of other vertebrates, whereas differences are mainly observed in the brainstem. The widespread distribution of NPY in the lizard brain suggests several modulatory functional roles, either in local-circuit systems of the forebrain, or in various limbic, neuroendocrine, and sensory pathways.  相似文献   
92.
The application of a model based on the three time dimensions of past, present and future can be used to generate an alternative taxonomy for the classification of depression, ill-being and quality of life. In relation to time, depression can be defined as the passage from a healthy past to a painful present, ill-being as the painful present of the individual and the quality of life (QOL) as the degree to which the subject's present life is commensurate with his aspirations. Such an approach opens up conceptual and methodological areas of research which will allow the construction of a new type of scale. Depression scales should be constructed with two time dimensions: past and present; ill-being scales only refer to the present and QOL scales should have two time dimensions: present and future. It would be possible to combine these three scales into a single scale with three dimensions. Such a scale would enable depression and ill-being to be quantified, accurately diagnosed and monitored. The relative importance of principal symptoms could be assessed, facilitating the choice of therapy and follow-up methods.  相似文献   
93.
94.
眼眶骨折眼球内陷功能性复位手术的临床观察   总被引:2,自引:1,他引:1  
目的:研究眼眶骨折眼球内陷手术复位的方法和手术最佳时期,探讨手术前后视功能变化。方法:应用螺旋CT影像和视觉电生理检查技术对100例施行眼眶重建和眼球复位手术的患者进行观察研究。结果:在早期手术的40例患者中,28例眼球内陷完全复位,12例改善;60例晚期手术中,32例完全复位,28例得到部分改善;手术前后视网膜电流图(F—ERG)和视觉诱发电位(P-VEP)无显著性差异。结论:采用人工材料行眼眶重建和眶内充填技术手术治疗眼球内陷可获得满意的疗效,早期手术效果优于晚期手术,手术创伤对视功能无明显影响,眼眶重建和眼球复位手术是安全可行的。  相似文献   
95.
Conners教师评定量表的中国城市常模和信度研究   总被引:11,自引:2,他引:9  
目的 建立Conners教师评定量表 (TRS)的中国城市常模 ,并对其进行信度检验。方法 在全国 14个城市对 35 76名儿童年进行Conners教师量表的评定 ,对其中 4 0名儿童间隔二周进行重测。结果 TRS各条目分与量表总评分之间的相关系数在 0 2 6 5~ 0 6 89;总问卷Cronbachα系数为 0 94 1,Spearman brown分半信度为 0 896 ,间隔二周量表总分的重测相关系数为 0 5 4 4 ,4个因子的重测相关系数在 0 391~ 0 6 71(P <0 0 1)。结论 Conners教师评定量表的中国城市常模符合我国国情 ,具有良好的信度 ,值得推广和应用。  相似文献   
96.
The aims of this study were (1) to elicit the users' responses to four electronic head-mounted devices (Jordy, Flipperport, Maxport and NuVision) and (2) to correlate users' opinion with performance. Ten patients with early onset macular disease (EOMD) and 10 with age-related macular disease (AMD) used these electronic vision enhancement systems (EVESs) for a variety of visual tasks. A questionnaire designed in-house and a modified VF-14 were used to evaluate the responses. Following initial experience of the devices in the laboratory, every patient took home two of the four devices for 1 week each. Responses were re-evaluated after this period of home loan. No single EVES stood out as the strong preference for all aspects evaluated. In the laboratory-based appraisal, Flipperport typically received the best overall ratings and highest score for image quality and ability to magnify, but after home loan there was no significant difference between devices. Comfort of device, although important, was not predictive of rating once magnification had been taken into account. For actual performance, a threshold effect was seen whereby ratings increased as reading speed improved up to 60 words per minute. Newly diagnosed patients responded most positively to EVESs, but otherwise users' opinion could not be predicted by age, gender, diagnosis or previous CCTV experience. User feedback is essential in our quest to understand the benefits and shortcoming of EVESs. Such information should help guide both prescribing and future development of low vision devices.  相似文献   
97.
We assessed the relations of visual hallucinations (VH) to cardiovascular autonomic dysfunction in patients with Parkinson's disease (PD). The subjects were 37 patients without VH (VH(-)) and 31 with VH (VH(+)). Autonomic function was evaluated on the basis of cardiac 123-radioiodinated metaiodobenzylguanidine (123I-MIBG) uptake and hemodynamic testing with Valsalva maneuver. Systolic blood pressure (SBP) and plasma norepinephrine concentrations (NE) were measured by tilt-table testing. 123I-MIBG uptake was lower in VH(+) than VH(-). Hemodynamic studies showed that VH(-) had only cardiac sympathetic and parasympathetic dysfunction, while VH(+) additionally had reduced vasomotor sympathetic functions. The fall in SBP during tilt-table testing was greater in VH(+) than VH(-). NE and its difference in the supine and upright positions were decreased in VH(+). We conclude that cardiac and vasomotor sympathetic dysfunction is more severe in VH(+) than in VH(-). Severe dysfunction in PD with VH is probably attributed to Lewy-body lesions or neuronal loss in sympathetic ganglia, the central autonomic system, or both.  相似文献   
98.
99.
Recently it has been suggested that a previously undetected, rhodopsin-based, visual pigment, located in some retinal ganglion cells and having a peak sensitivity around 460 nm, may be responsible for light-induced melatonin suppression and, perhaps, maintenance of the circadian rhythm. Using data from the literature, it is shown that, as absorption in the crystalline lens for shorter visible wavelengths increases substantially with age, while the pupil diameter tends to decrease, the effective retinal exposure received under the same ambient lighting conditions by the pigment is almost 10 times lower in an old, as compared with a young, eye. Interestingly, replacement of the old crystalline lens by an intraocular implant restores the exposure to youthful levels. The possible effects of these changes with age on circadian rhythms are discussed.  相似文献   
100.
Background: Field studies of the duration of fixation during daytime driving find that it is about 0.2 seconds on average. Thus, the time available to read traffic signs is often limited. There are other circumstances where time to read alphanumeric messages is limited. Data relating time of observation are needed for purposes of ergonomic design as the data available in the literature are limited and uncertain. Method: Visual acuity was measured using Landolt rings in negative contrast, which were presented on a computer screen with a background luminance of 32 cd/m2 for durations that varied between two and 0.02 seconds at three different contrasts. Resulte: Visual acuity depends on the log of the light dose reduced by a factor that may be related to absorption of the light by the eye media. For young observers, it was found that: VA = 0.57 (log C t) + 1.705, where C is the contrast and is expressed as δL/L, where δL is the difference between target and background luminances in cd/m2 and t is the observation time in seconds. Conclusion: This formula or the functions fitted to the data obtained can be used to calculate the increase in target size needed to allow for short observation times.  相似文献   
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