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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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Summary The differentiation state of skin epithelial cysts and some uncommon types of epithelial skin tumours was investigated by immunohistochemical staining, mainly using cytokeratin (CK) polypeptide-specific monoclonal antibodies. Samples of interfollicular epidermis, hair follicles and eccrine sweat glands were included as reference tissues. The CK reactivity in epidermoid cysts and milia is not restricted to CKs involved in epidermal-type differentiation, i.e. CK1, 5, 10 and 14, but in addition CK16, a hyperproliferative keratinocyte marker is suprabasally expressed. CK1 and 10 are other prominent suprabasal markers, while CK14 seems to be preferentially expressed in the basal cell layer. Of the non-epidermal CKs, only CK4 was focally or more extensively detected in about 50% of the cases. In terms of CK reactivity, keratinization of trichilemmal cysts corresponds to the keratinization of the anagen-phase hair follicle in the isthmus. The CK reactivity is again restricted to CK1, 5, 10, 14 and 16. However, the CK1 as well as CK10 reactivity is subject to serious limitations, since both CKs were only convincingly observed in foci of terminal differentiation. Eccrine hydrocystoma obligatorily expresses a complex CK set, including CK7, 8, 14, 18 and 19. This CK set perfectly corresponds to the CK composition observed in acini of eccrine sweat glands. In addition, a discontinuous CK4 and 16 reactivity was seen in about 50% of the sites, while CK1 and 10 displayed a strictly focal appearance. On the other hand, syringoma produces in its distinct structures, a CK pattern reminiscent of the one observed in eccrine sweat gland ducts and includes CK1, 5, 10, 14, 16 and 19. Finally, the CK expression pattern of pilomatricoma includes CK1, 8, 10, 14 and 19, and is reminiscent of the CK staining of hair bulb matrix cells differentiating in the keratogenous zone in the direction of hair cortex. The reactivity of CK1 and 10 was mainly restricted to foci of squamoid differentiation and also to transitional cells bordering on shadow cells, as far as it concerns CK10. Occasionally, CK7 and 16 were observed in individual cells or small cell groups. In our view these CK reactivity patterns are useful to judge the differentiation state reached in pathological conditions, but so far do not allow us unequivocally to determine the site of origin of these lesions.  相似文献   
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用气相色谱研究抗氧化剂对膜脂肪酸的保护作用   总被引:3,自引:0,他引:3  
卢基贵  王伟  陈文为 《药学学报》1991,26(6):406-410
本文应用气相色谱技术直接测定三种生物膜(人红细胞膜,人血小板膜和鼠肝线粒体膜)多不饱和脂肪酸的含量变化,检测脂质过氧化程度。实验证实几种多羟酚类化合物(儿茶精,阿魏酸钠和没食子酸及其衍生物)不同程度地抑制(OH)诱导的脂质过氧化反应,并呈量效和构效关系。这类抗氧化剂对保护生物膜的结构与功能是有益的。  相似文献   
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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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