创伤后迟发性脑肿胀的临床特点与治疗

目的 探讨创伤后迟发性脑肿胀的临床特点、发病机制与治疗。方法 回顾性分析1998年1月～2005年6月年收治的17例迟发性脑肿胀患者的临床特点和救治情况。结果 所有颅脑损伤患者采用保守治疗后均有好转，但于伤后5-10d出现恶化，CT复查有脑肿胀，经加强综合脱水等治疗后16例治愈，1例死亡。结论 迟发性脑肿胀好发于对冲性额、颞叶挫裂伤伴明显蛛网膜下腔出血、硬膜下薄层血肿及早期CT有脑肿胀者。其发病机制可能与创伤后的迟发性脑血管痉挛、微循环障碍、静脉回流障碍及甘露醇作用下降等因素有关。此类患者病情隐蔽性强，应加强观察、积极行CT复查，如能早期明确诊断，保守治疗多数效果良好。     

Presence of pancreatic hormones in islet cells with MHC-class II antigen expression

In the normal rat pancreas, only few islet cells express MHC-class II antigens. Their nature and function has not yet been elucidated. We report a method for the purification of Ia-positive islet cells by fluorescence-activated cell sorting. The isolated mononuclear cells appear of nonendocrine origin but contain vacuoles with partially digested secretory vesicles. Both insulin- and glucagon-immunoreactive granules were identified in these vacuoles of varying size and composition. It is suggested that at least part of the rat islet cells with class II antigen expression can exhibit phagocytotic properties leading to the uptake of fragments from damaged endocrine cells. This functional characteristic may implicate this particular islet cell type in the pathology of the endocrine pancreas in type I diabetes.     

Retrorenal colon: implications for percutaneous diskectomy

It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary.     

Dual-energy X-ray absorptiometry of lumbar vertebrae: relative contribution of body and posterior elements and accuracy in relation with neutron activation analysis.

The bone mineral content of 34 lumbar vertebrae obtained from ten cadavers (three men, seven women; age 61-88 years) was measured using a pulsed source dual-energy X-ray absorptiometry (DEXA) apparatus. Scanning was performed in the frontal projection and was repeated on the vertebral bodies obtained after removal of the posterior elements of the vertebrae. Subsequently a nondestructive neutron activation analysis (NAA) was performed. The mineral content of the vertebral bodies was found to represent (mean, SEM) 53.0% (1.9%) of the content of the whole vertebrae. The mineral content of the vertebral bodies assessed with NAA (BMC NAA) and with DEXA (BMC DEXA) showed a high correlation: BMC NAAA = (1.016 x BMC DEXA) + 0.990 r = 0.949 (p less than 0.001). We conclude that the mineral content of lumbar vertebral bodies can be accurately measured in vitro in a water environment by DEXA, and that the mean contribution of the posterior elements of the vertebra to the calcium hydroxyapatite content of whole vertebrae measured in the frontal projection is as high as 47.0%.