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131.
目的:报道12年来局部应用丝裂霉素治疗弥漫性或多灶原发性获得性非典型黑变病(PAM)及结膜黑色素瘤的体会。方法:16例患者的干预病例研究。10例残余上皮病患者(8例为PAM,2例为结膜黑色素瘤)首选丝裂霉素治疗,6例在经手术切除或冷冻后用丝裂霉素辅助治疗。首选治疗时用0.04%丝裂霉素,4次/d,治疗28d(14d为1疗程,共2个疗程),辅助治疗时要连用7d。观察患者局部复发及全身转移情况。结果:16例患者,治疗后平均随访81个月(极差13—144个月)。所有患者对于化疗均有效。8例复发(3例为辅助治疗组,5例为首选治疗组),3例行眶内容物剜除术,其余5例接受保守治疗。平均复发时间为36.9个月。  相似文献   
132.
Purpose This study was conducted to investigate a case of reactive lymphoid hyperplasia following laser assisted in situ keratomileusis (LASIK). Methods A 31-year-old man who underwent LASIK presented 1 month later with a fleshy conjunctival (plical) tumor in the left eye. An excision biopsy of the tumor was performed. Results Histopathology of the excised tumor revealed reactive lymphoid hyperplasia. Discussion Conjunctival lymphomas can masquerade as chronic conjunctivitis and can be preceded by reactive lymphoid hyperplasia. It is important to identify and differentiate these tumors. This report describes the unusual occurrence of a lymphoid conjunctival tumor after LASIK eye surgery.  相似文献   
133.
The clinical, ultrasonographic, and histopathologic characteristics of an oncocytoma of the conjunctiva are described. A 49-year-old woman presented with a red-orange lesion adjacent to the caruncle in her left eye. A clinical examination including high-frequency ultrasound was performed prior to excisional biopsy of her tumor. High-frequency ultrasound demonstrated an epibulbar tumor with low internal reflectivity and a cystic component. There was no involvement of the underlying sclera. Multiple hypoechoic components of the tumor stroma were correlated to multiple cystic glandular structures on histopathologic evaluation. The excised tumor was diagnosed to be an oncocytoma.  相似文献   
134.
Gustatory afferent fibers of the vagus nerve that innervate taste buds of the oropharynx of the goldfish, Carassius auratus, project to the vagal lobe, which is a laminated gustatory nucleus in the dorsal medulla. As in the mammalian gustatory system, responses by second-order cells in the goldfish medulla are mediated by N-methyl-D-aspartate (NMDA) and non-NMDA ionotropic glutamate receptors. We utilized a cobalt uptake technique to label vagal lobe neurons that possess cobalt-permeable ionotropic glutamate receptors. Vagal lobe slices were bathed in kainate (40 microM) or glutamate (0.5 or 1 mM) in the presence of CoCl(2), which can pass into cells through the ligand-gated cation channels of non-NMDA receptors made up of certain subunit combinations. Cobalt-filled cells and dendrites were observed in slices that were activated by kainate or glutamate, but not in control slices that were bathed in CoCl(2) alone, nor in slices that were bathed with the non-NMDA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione (10 microM) in addition to an agonist. Likewise, simple depolarization of the cells with KCl failed to induce cobalt loading. Cobalt-filled round unipolar cells, elongate or globular bipolar cells, and multipolar cells with elongate or polygonal perikarya were distributed throughout the cell layers in the sensory zone of the vagal lobe. Numerous labeled neurons had dendrites spanning layers IV and VI, the two principal layers of primary afferent input. Apical and basal dendrites often extended radially through neighboring laminae, but many cells also extended dendrites tangential to the lamination of the sensory zone. In the motor layer, cell bodies and proximal dendrites of small, multipolar neurons, and large motoneurons were regularly loaded with cobalt.  相似文献   
135.

Background  

To reduce the risk of brain damage children with acute lymphoblastic leukaemia (ALL) are nowadays mainly treated with intrathecal chemotherapy (ITC) instead of central nervous system (CNS) radiation therapy (CRT) to prevent CNS relapse. However, chemotherapy may also lead to cognitive deficits. As growth hormone deficiency (GHD) or impaired growth hormone secretion are frequently found in ALL patients treated with cranial radiation therapy and/or chemotherapy, we hypothesized that GH therapy may reduce cognitive deficits in these patients.  相似文献   
136.
While tobacco smoke has been conclusively identified as a lung carcinogen, there is much debate over which smoke constituent(s) are primarily responsible for its carcinogenicity. Previous studies in our laboratory suggested that highly lipophilic carcinogens are slowly absorbed in the thicker epithelium of the conducting airways, potentially allowing for substantial local metabolism. The bioactivation of polycyclic aromatic hydrocarbons in airway epithelium may, hence, be important in tobacco smoke-induced carcinogenesis. In the present study, the hypothesis of slow absorption and substantial local metabolic activation of highly lipophilic carcinogen in airway epithelium was tested in dogs. A single dose of tritiated benzo[a]pyrene (BaP) dissolved in a saline/phospholipid suspension was instilled in the trachea, just anterior to the carina. At intervals of a few minutes up to 30 min over a 3-h period, blood samples were drawn from the azygous vein, which drains the area around the point of instillation, and from the systemic circulation. Tissue samples were taken at the end of the experiment. The concentration of BaP with depth into the tracheal mucosa was determined with autoradiography. BaP was slowly absorbed into the trachea with a half-time of approximately 73 min, which is consistent with diffusion-limited passage through the epithelium and lead to local doses in the tracheal epithelium that were more than a 1000-fold those of other tissues. The long retention of BaP in the epithelium provided the local metabolizing enzymes with high substrate levels over a long period, resulting in extensive metabolism. At 3 h after the exposure, 23% of the BaP-equivalent activity remained in the tracheal mucosa. Of this fraction, 13% was parent compound, 28% was organic extractable, 31% was water-soluble, and 28-7% of the instilled dose was bound to tracheal tissues. These results explain the tendency of highly lipophilic carcinogens, such as BaP, to induce tumors at the site of entry and, furthermore, indicate that the highly lipophilic components of tobacco smoke and polluted air may be the most important contributors to lung tumors of the conducting airways.   相似文献   
137.
138.
It is an honour to have been asked to contribute to this volume that commemorates the life and work of Spyros Doxiadis. Spyros was, and is still, a vital and stimulating influence on those of us who were fortunate enough to have been his colleague in all phases of his life. My period of closeness to him was when he was working in Sheffield with Ronald Illingworth. At that time (now over 40 years ago) he and Katherine were having their children and my wife and I was having ours. Then words like "bonding" had not become commonplace as today, but the functional patterns of family relationships were something about which we were intensely aware. I particularly remember a summer when we were holidaying on a tidal estuary between Anglesey and Holy Island and recall a moment when Spyros and I were sitting on a grass topped sandbank watching our children and wives at the water's edge "messing around" with a boat. We watched and discussed the beauty of the postures and poses of our womenfolk with the children and the children with each other. It was the memory of that conversation that stimulated me to propose the topic of this essay in Spyros' memory.  相似文献   
139.
A total of 130 short children were included in a French multicentre study and randomized between a control group (group A) and two groups treated with daily subcutaneous injections of GH at doses of 0.7 IU/kg/week (group B) and 1.4 IU/kg/week (group C) for 2 years. Height velocity was significantly increased ( p <0.0005) in groups B and C, with a greater increase in group C than in group B ( p < 0.001). The benefit after 2 years compared with controls was 4.3 cm in group B and 5.9 cm in group C. The rate of bone maturation was not affected by GH therapy. These results led to the conclusion that 2 years of treatment with GH improves final height prognosis in children with short stature secondary to IUGR, and that this effect is dose dependent. The effect on final height has still to be demonstrated.  相似文献   
140.
Components of the Integral implant system, prosthodontic methods, and uses for the implant system have been described. The system is most effective in the restoration of edentulous areas of the maxillary and mandibular arches.  相似文献   
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