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21.
医源性胆管狭窄X线表现   总被引:1,自引:0,他引:1  
本文报道了13例医源性胆管狭窄,分析其影像表现。特点为:环形狭窄;线样狭窄,包括规则的和不规则的线样狭窄;闭塞性狭窄;胆管闭塞和胆管中断分离。ERCT和PCT对狭窄的形态,位置及长度显示优于CT和US。  相似文献   
22.
放射性肝纤维化过程的定量研究   总被引:6,自引:0,他引:6  
经^60Coγ线照射大鼠肝区,通过光镜、电镜和图像分析仪、宣研究了照后1年肝脏的病理改变。结果表明,30Gy组在照射后1年内逐渐发生了放射性肝纤维化病变。在肝纤维化发生过程中,肝细胞内糖原颗凿含量进行性减少,间质中胶原纤维含量进行性增加,网状纤维于照射1-3个月呈进行性增加。  相似文献   
23.
One of the pyrimidine compounds, 2-piperadino-6-methyl-5-oxo-5,6-dihydro(7H)pyrrolo[3,4-d]pyrimidine (MS-818), has neurotropic effects in vitro. Therefore, we studied the effect of MS-818 on the regeneration of the peroneal nerve in C57BL/6J mice after a crush injury. Two test groups, which received a daily intraperitoneal injection of 5 mg/kg or 10 mg/kg MS-818, respectively, were compared with controls, which received daily intraperitoneal injections of physiological saline, over a 14-day period. The maximum foot-width ratio (crushed side/uncrushed side) was obtained on days 1, 8 and 14 after the crush injury, and the various morphometric parameters were evaluated at both 5 and 10 mm distal to the proximal portion of the crush site. The significant effects of MS-818 included a larger maximum foot width (P<0.04) and a greater number of unmyelinated axons per nerve at both levels (P<0.003) in both test groups than in controls. MS-818 had no significant effects on body weight, the increase of total transverse fascicular area after the crush injury, the total number of myelinated fibers with their size distributions, or the number of nuclei of Schwann cells and macrophages. Therefore, we conclude that MS-818 promotes axonal sprouting and elongation after a crush injury in mice.  相似文献   
24.
38例非小细胞癌脑转移的综合治疗分析   总被引:1,自引:1,他引:0  
目的探讨非小细胞肺癌脑转移的有效治疗方案.方法对38例非小细胞肺癌脑转移患者进行头部、胸部放疗并结合全身化疗的综合治疗.结果近期疗效的有效率为76.3%(29/38).神经精神症状缓解率73.7%(28/38),肺部症状缓解率60.5%(23/38).1年生存率31.5%(12/38),2 a生存率10.5%(4/38).结论合理采用综合治疗可有效提高非小细胞肺癌脑转移患者的生存率.  相似文献   
25.
神经干细胞移植治疗缺氧缺血性脑损伤的实验研究   总被引:23,自引:4,他引:19  
目的 研究神经干细胞移植治疗缺氧缺血性脑损伤的可行性。方法 取孕龄为12-16天的母鼠,从胎脑中分离神经细胞,进行培养、鉴定。用出生7天的SD大鼠的新生鼠制作缺氧缺血性脑损伤的动物模型,7天后接受神经干细胞移植(移植组,n=16只),同时设置对照组,只注射磷酸缓冲液(对照组,n=8只),8-10周后,作Y迷宫实验检测大鼠的学习能力和记忆能力。取脑组织作免疫组织化学检查。结果 从大鼠胎脑中成功培养出神经干细胞,培养条件下呈悬浮状态生长,形成神经球,绝大多数的细胞表达神经干细胞的标志物神经巢蛋白(nestin)。接爱神经干细胞移植组大鼠的学习能力、记忆能力和对照组相比,有明显提高,差异具有显著性(P<0.05)。接受神经干细胞移植大鼠组织中可见存活的移植细胞,并和宿主脑组织融合在一起。结论 在体外培养条件下,可从胎脑组织中培养出神经干细胞,移植到缺氧缺血性脑损伤大鼠脑内后,细胞与宿主的脑组织融合在一起,动物的学习、记忆能力有改善。移植神经干细胞是治疗缺氧缺知性脑损伤的有效方法之一。  相似文献   
26.
本文分析了214例高热惊厥,结果为:检出率4.35%;男女之比为1.61:1;好发年龄为6个月~6岁(93.5%);首发年龄为6个月~4岁(89.9%);惊厥发作时体温多在39℃以上(74.6%);惊厥发作多在发热后12h内(72.4%);每次热病中惊厥发作1~3次(99.5%);惊厥持续时间多在15min内(91.0%);致惊厥发作的热性疾病以上呼吸道感染为最多;214例中63例复发,其中2例转癫痫,61例尚未发现智力低下或其他异常。从2例转癫痫的临床及脑电图看,提示惊厥发作愈重,持续时间愈长,转癫痫的可能性愈大。  相似文献   
27.
Intraventricular hemorrhage (IVH) in preterm infants is well known to be associated with the high morbidity and mortality of this group. Previous studies have suggested altered cerebral blood flow (CBF) as an important pathologic factor. We measured the CBF in nearterm rabbit fetuses using the hydrogen clearance technique. The local CBF of the rabbit fetuses was significantly low compared with that of the maternal rabbits. The response of CBF to changes in PaCO2 was observed in rabbit fetuses. The CO2 reactivity index of the fetal rabbit was lower than that of the maternal rabbit. This low CO2 reactivity might reflect the immaturity of the fetal brain and its low CBF. We were unable to monitor the fetal blood pressure, but the fetal CBF remained stable when the maternal blood pressure was altered. It is well known that IVH in preterm infants originates from the subependymal germinal matrix and that this has many fragile vessels. Our observation suggests that even a small increase of CBF during hypercapnia might have a large effect towards producing hemorrhage.  相似文献   
28.
29.
After the interaction of estrogen with the ligand binding domain (LBD) of mouse estrogen receptor‐α (mERα) and hormone‐responsive elements of target genes, many nuclear proteins are recruited to regulate the expression of specific genes. Because it is not known which brain proteins interact with LBD or whether these proteins vary with age and sex, we used pull‐down assay and far Western blotting to detect five nuclear proteins of 160, 140, 87, 60, and 46 kD in the mouse brain. These interacting proteins were identified as PELP1, RIP140, PGC1α, BAF60, and ADA3, respectively. The level of PELP1, RIP140, PGC1α, and BAF60 decreased drastically in old compared with adult male mice, whereas the ADA3 level showed no significant change. PELP1, PGC1α, and BAF60 levels were lower in old male compared with female mice. Thus we report the identification and interaction of five nuclear proteins with mERα‐LBD, indicating their role in estrogen signaling and brain functions during aging. © 2009 Wiley‐Liss, Inc.  相似文献   
30.
Objectives –  To assess long‐term functioning and disability after traumatic brain injury (TBI). Material and methods –  Individuals (n = 88) in Norrbotten, northern Sweden, who had been transferred for neurosurgical care were assessed with internationally established TBI outcome measures 6–15 years post‐injury. Results –  There was an improvement in overall outcome from discharge from inpatient rehabilitation to follow‐up. Many individuals had a high degree of motor and cognitive functioning, which enabled them to live independently in their own home without assistance, but there remained a disability related to community reintegration and social participation. This affected their productivity and to some degree their marital stability. The remaining disability and reduced productivity were related to the age at injury and the injury severity. Conclusions –  Our data showed that individuals with a TBI can achieve and maintain a high degree of functioning many years after the injury. Increasing age and a greater injury severity contributed to their long‐term disability.  相似文献   
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