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51.
Three patients with histologically confirmed sarcoidosis with spinal cord involvement were examined with high-field-strength magnetic resonance imaging (1.5 T) before and after the administration of gadolinium diethylenetriaminepentaacetic acid. In addition to intramedullary expansion, areas of patchy, multifocal, parenchymal enhancement and areas of linear peripheral enhancement were seen in all three patients; these findings have not been previously reported and are unusual for other more common spinal cord lesions. This observation led to a correct diagnosis and a limitation of the extent of biopsy in two of the cases. Unfortunately, this enhancement pattern is not specific for sarcoidosis, as the authors have observed similar findings in two cases of biopsy-proved myelitis and multiple sclerosis. The peripheral enhancement is thought to be located in the leptomeninges due to leptomeningeal involvement, which was proved histologically in one case. This pattern of involvement, while not specific, is certainly consistent with and, in the appropriate clinical setting, highly suggestive of sarcoidosis.  相似文献   
52.
脉冲电流对胰岛素经皮渗透的促进作用   总被引:4,自引:0,他引:4  
实验结果表明,脉冲电流能有效地提高胰岛素的透皮扩散速率,并随着释放池中胰岛素浓度的递增,透皮扩散速率呈线性增加。同时,胰岛素在pH值偏离等电点的酸性溶液(pH3.6)中透皮速率最高,为324.2±33.4μU/(cm2·h),而在pH值高于等电点的溶液(pH7.4)中其透皮速率降至143.7±27.3μU/(cm2·h),在pH值接近等电点(pH5.3)时,胰岛素的透皮速率最低,为78.4±21.9μU/(cm2·h)。  相似文献   
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54.
体外培养的肝细胞有多种临床用途〔1〕。其中将肝细胞置入特殊的生物反应器,构建生物人工肝(bioartificialliver,BAL)支持系统有重要的临床价值。有研究报道,细胞聚集成多细胞的球体(spheriod)更类似于体内条件;并且可在有限的容积内高密度地培养肝细胞〔2〕。因此,我们实验构建人、猪肝细胞球体,并比较肝细胞普通培养与球体培养蛋白分泌功能的变化。1.材料和方法:试剂:Dubecco′s磷酸盐缓冲液;Hank′s平衡盐;ITS(胰岛素,运铁蛋白和硒,insulin,transfer…  相似文献   
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56.
Rotator cuff sonography: a reassessment   总被引:4,自引:0,他引:4  
Brandt  TD; Cardone  BW; Grant  TH; Post  M; Weiss  CA 《Radiology》1989,173(2):323-327
This study is both a retrospective and prospective evaluation of the clinical usefulness of shoulder sonography. Ninety-eight patients suspected of having rotator cuff tears underwent sonography of both shoulders. Sixty-two patients underwent double-contrast arthrography performed on the same day as sonography, and 38 patients underwent surgery after sonography. A comparison of the results from ultrasound and arthrography, using published diagnostic criteria, demonstrated a sensitivity of 75% and a specificity of 43% for detection of a rotator cuff tear. In this study, use of more restricted criteria, a subset of the published criteria, yielded a sensitivity of 68% and a specificity of 90%. A comparison of sonography with surgery, using this study's criteria, demonstrated a sensitivity of 57% and a specificity of 76%. This report shows that shoulder sonography is less reliable than previously reported and appears to have a very limited role in the evaluation of rotator cuff injuries.  相似文献   
57.
野花椒系芸香科植物(Zanthoxylum simulans Hance),其根皮有止痛及局麻作用。其水溶性生物碱有肌松作用,曾用于外科手术作为中麻辅助用药。常志青从中分离到加钖果宁[(—)edulinine,简称加钖碱,下同],并发现有镇痛及中枢抑制作用。本文进一步证明其镇痛作用及其作用机制与阿片受体有关。  相似文献   
58.
Equivocal mammographic findings: evaluation with spot compression   总被引:3,自引:1,他引:2  
Berkowitz  JE; Gatewood  OM; Gayler  BW 《Radiology》1989,171(2):369-371
Seventy-five spot compression views of equivocally suspicious lesions detected at routine mammographic examination of 72 women were reviewed in this retrospective study. Sixty-five of the 75 lesions appeared less suspicious on spot compression views, two did not change, and eight appeared more suspicious. Biopsy findings confirmed that the eight more suspicious lesions were cancer. The adjunctive use of spot compression helped characterize equivocal findings seen on routine mammographic views and improved the accuracy of mammographic interpretation.  相似文献   
59.
Breast calcifications: analysis of imaging properties   总被引:1,自引:0,他引:1  
Olson  SL; Fam  BW; Winter  PF; Scholz  FJ; Lee  AK; Gordon  SE 《Radiology》1988,169(2):329-332
The imaging characteristics of microcalcifications in both benign and malignant breast conditions were analyzed in 48 digitized film mammograms. Each case included in this analysis had findings considered suggestive of malignancy by the radiologist, with the underlying histologic structure determined by excisional biopsy. Imaging properties of each microcalcification--such as pixel intensity, relative location, distribution, size, and local neighborhood intensities--were recorded. This information was statistically analyzed at the population level according to such selection criteria as histologic type, size of calcification, and cluster size. Distribution ranges were determined for these criteria. Statistical differences between data from benign and malignant cases show the average distance between calcifications in malignant conditions was greater than in benign conditions, and tissue region averages surrounding calcifications associated with malignant conditions were consistently higher than those for benign conditions.  相似文献   
60.
Paranasal sinuses: CT imaging requirements for endoscopic surgery   总被引:17,自引:0,他引:17  
Recent advances in the understanding of mucociliary activity and the pathophysiology of the nasal cavity and paranasal sinuses have revolutionized the surgical management of chronic and/or recurrent sinusitis. Meticulous radiographic delineation of the small structures in this region, coupled with endoscopic evaluation, provides detailed preoperative information regarding morphology and pathology. This information has led to more focused endoscopic surgical procedures, which have dramatically reduced patient morbidity. As a consequence, there is now worldwide interest among otolaryngologists in the radiologic definition of paranasal regional anatomy. For effective interactions between radiologist and otolaryngologist, the former must be prepared to render interpretations that address these "microanatomic" locales. This communication is directed at familiarizing the radiologist with these observations and concepts, considering both normal and disturbed anatomy with their attendant pathophysiologic and therapeutic implications.  相似文献   
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