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1.
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。  相似文献   
2.
A procedure was developed to conduct simultaneously immunocytochemical and neurochemical studies on the serotonergic system in adjacent 300-micron-thick slices of rat hippocampus. This procedure was applied to correlate morphological (innervation pattern and density), neurochemical (5-hydroxytryptamine and 5-hydroxyindolacetic acid levels and [3H]5-hydroxytryptamine uptake and release) and behavioral (spatial learning) effects of neurotoxin-induced denervation and reinnervation by grafting fetal mesencephalic raphe cells. Intracerebroventricular injections of a low dose of 5,7-dihydroxytryptamine caused a discrete serotonergic denervation of the hippocampus. Eleven months after lesioning, 5-hydroxytryptamine and 5-hydroxyindolacetic acid levels and [3H]5-hydroxytryptamine uptake capacity were decreased by 50-60%. By this time, the residual fibers displayed an enhanced vulnerability towards K(+)-induced depolarization. Grafting of a fetal raphe cell suspension resulted in a reinnervation of the host hippocampus. The pattern of reinnervation was comparable to control innervation and the density was supranormal at the level of the graft. As observed semiquantitatively, the innervation density decreased with distance from the core of the graft. Neurochemical studies showed that the fibers were capable of synthesizing, metabolizing and releasing 5-hydroxytryptamine. The turnover of 5-hydroxytryptamine in both the denervated and the reinnervated hippocampus was comparable to that in control tissue. Previous behavioral testing of the denervated and of the denervated and implanted animals did not reveal any effect on spatial learning, either in an individual or in a social test paradigm. The latter data substantiate the notion that interference with the hippocampal serotonergic innervation does not hamper adequate spatial learning.  相似文献   
3.
Retrorenal colon: implications for percutaneous diskectomy   总被引:1,自引:0,他引:1  
Helms  CA; Munk  PL; Witt  WS; Davis  GW; Morris  J; Onik  G 《Radiology》1989,171(3):864-865
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.  相似文献   
4.
Triphalangeal thumb (TPT) is a rare congenital disorder characterised by a long, finger-like thumb with three phalanges instead of two. It can occur as an isolated defect, in association with other abnormalities of the hands and feet, or as a part of a syndrome. Sporadic cases have been described, but it is usually inherited as an autosomal dominant trait. In order to examine skeletal morphology in different phenotypic variations of this disorder, we performed metacarpophalangeal pattern profile analysis in one kindred with this disorder. A characteristic profile occurred in all affected people, based on the individual lengthening or shortening of the thumb bones. Comparison of the affected and unaffected people from this family with people with a different genetic background suggests that the described profile is specific for TPT and could be used as a helpful diagnostic tool in syndromes which include TPT.  相似文献   
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Experimental allergic encephalomyelitis (EAE) is an autoimmune inflammatory disease of the central nervous system (CNS). In particular in the CsA-induced chronic relapsing form (CREAE), pronounced demyelination occurs, in temporal association with relapses. It is still a matter of discussion which cell type ultimately is responsible for the actual process of demyelination. Macrophages, cytotoxic T lymphocytes and also astrocytes are possible candidates. In this short overview, the role of macrophages in the pathogenesis of EAE is discussed. It is shown that in particular, newly recruited macrophages play a crucial role in the generation of clinical signs. Possible mechanisms by which macrophages are involved in the pathogenesis of demyelinating diseases are presented.  相似文献   
10.
A rapid recovery of specific humoral immunity in the recipient of an allogeneic bone marrow transplantation (BMT) can be observed after immunization of the donor before graft sampling. This has been attributed to transfer of specific immunity from donor to recipient. However, to maintain the concept of transfer the origin of the antibody producing cells in the recipient after BMT must be demonstrated. To this end, donor-recipient pairs with differences in Gm-allotypes were selected and immunized before BMT with the neo-antigen Helix pomatia haemocyanin (HPH) according to three immunization protocols. Additionally, the recipients were immunized at day 42 after BMT. Serum samples were weekly obtained from the recipients in the first 100 d after BMT. The origin of HPH-specific antibody producing cells was assessed by two approaches: (1) determination of the Gm-allotypes of anti-HPH antibodies within a distinct IgG subclass, (2) analysis of anti-HPH antibody spectrotypes by isoelectric focusing combined with immunoblotting. The results obtained with these two approaches show concordance in most instances and led to the conclusion that the antibody producing cells are of donor origin.  相似文献   
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