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91.
Russell SM Elliott R Forshaw D Kelly PJ Golfinos JG 《中国神经肿瘤杂志》2005,3(4):295-295
OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance. 相似文献
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As part of the development of a rapid in vivo screen for prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae by assessing the acute effects of prototypic drugs that act on the central nervous system. Initially, we chose ethanol, d-amphetamine, and cocaine, which are known, in mammals, to increase locomotion at low doses and decrease locomotion at higher doses. Wild-type larvae were individually maintained in 96-well microtiter plates at 26 °C, under a 14:10 h light:dark cycle, with lights on at 0830 h. At 6 days post-fertilization, ethanol (1–4% v/v), d-amphetamine sulfate (0.1–20.0 µM) or cocaine hydrochloride (0.2–50.0 µM) were administered to the larvae by immersion. Beginning 20 min into the exposure, locomotion was assessed for each animal for 70 min using 10-minute, alternating light (visible light) and dark (infrared light) periods. Low concentrations of ethanol and d-amphetamine increased activity, while higher concentrations of all three drugs decreased activity. Because ethanol effects occurred predominately during the light periods, whereas the d-amphetamine and cocaine effects occurred during the dark periods, alternating lighting conditions proved to be advantageous. These results indicate that zebrafish larvae are sensitive to neuroactive drugs, and their locomotor response is similar to that of mammals. 相似文献
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Garn.JG 《河南职工医学院学报》2000,12(4):F003-F003
本对医学院校学生就全科医生有关问题给于相应的答复,其中还包括自1997年以来由美国全科医学会举办的学生代表大会上所提出的一些问题,例如:什么是全科医生?全科医生的行业范围是什么?全科医生的工作,生活及收入情况如何等等问题。(Am.Fam.Physician1990.60:167-174)。 相似文献
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Experimental pneumococcal pneumonia was produced in albino rats by intrabronchial inoculation of Type I pneumococci suspended in mucin. The resulting pneumonia was uniformly fatal in untreated rats. Eighty per cent of the animals so infected and treated with sulfonamide drugs 6 hours after inoculation survived the pneumonia. At the end of 1 week the surviving animals were sacrificed, and examination of the lungs showed sharply demarcated localized pulmonary lesions containing no pneumococci. Microscopic study of the lungs of treated animals sacrificed at 6, 18, 42, 66, 96, and 168 hours after the start of treatment revealed the following sequence of events. During the first 18 hours the drug apparently had little effect upon the pneumonic lesion, but at the end of 18 hours pneumococci in the edema zone began to show striking changes in their morphology, indicating bacteriostesis. Forty-two hours after the start of treatment the edema zone had disappeared, the pneumonia had ceased to spread, and the pneumococci at the margin of the lesion had been overtaken by leucocytes. Careful examination of the exudate in the periphery of the lesion revealed definite phagocytosis of pneumococci. By the 4th day no pneumococci could be found in the stained sections, and after 1 week there remained only macrophages in the rapidly clearing alveoli. In order to demonstrate the phagocytic reaction more clearly the effect of sulfonamide drugs was studied in pneumonic rats previously rendered leucopenic by exposure to x-ray. The pneumonia in these animals was relatively acellular, and the few macrophages present in each alveolus could be seen to have phagocyted large numbers of pneumococci after 18 to 42 hours of treatment. The macrophages not only phagocyted the pneumococci but ultimately destroyed them, the pneumonic lesion later going on to complete resolution. The fact that this phagocytic reaction was observed in the lungs of animals with bacteremia suggests that the phagocytosis is independent of circulating type-specific opsonins. 相似文献
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