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31.
Lymphoblastic lymphoma, an aggressive mediastinal mass, is recognized as serious threat to the patient in developing cardiac tamponade or airway obstruction. Surgical procedure is often required to relieve clinical emergency and to establish prompt pathological diagnosis. However, in such a patient, acute respiratory occlusion in the spine position can be a life-threatening complication during general anesthesia. We describe a 17-year-old man whose cardiac tamponade was treated by pericardial-pleural window through a left anterior thoracotomy in the lateral position. The patient recovered from hemodynamic compromise without showing respiratory occlusion during general anesthesia and remained in the lateral position until extubation. Pathological diagnosis was precursor T-lymphoblastic lymphoma. There were no complications attributable to the operative procedure. Further chemotherapy reduced the mediastinal mass in size after two weeks when the patient developed sepsis and died. Lateral position prevents respiratory occlusion during surgical procedure under general anesthesia in the patient of huge anterior mediastinal tumor with airway obstruction.  相似文献   
32.
中央沟上段及其邻近沟回的体表定位及其临床意义   总被引:2,自引:0,他引:2  
目的:探讨在MRI和CT图像上观测中央沟上段及其邻近沟回的特征,进行精确体表定位。方法:30例成人头颅和扫描无颅恼器质性病变10份CT,100份MRI片,在头颅正中欠状面上观测头颅外形和平行于耳眦线平而以上100mm内的前后正巾线的中点及中垂线。在横位图像上观测中央沟上段及其邻近沟回的特征和二维坐标参数。结果:成人头颅近似标准球形。住82%头颅卜平行耳眦线平面的正中点的的投影在垂直耳眦线过外耳道的直线卜,另外18%偏离基线面中垂线小于7mm。上段中央沟在耳眦线平面上70~95mm。84%额上沟与中央前沟相交呈倒T字征,交点住前后中线旁24~27mm,耳眦线平面的中垂线前2~6mm。中央沟上段起点前后中线旁1~15mm,耳眦线平而的中垂线后12~28mm,手结征98%。中央后沟在中央沟之后8~13mm与其平行。结论:每人上段中央沟及其邻近沟回的特征能被MRI精确体表定位。  相似文献   
33.
34.
The aortic nipple, a small “pseudotumor” adjacent to the aortic arch, is the left superior intercostal vein. In our series of 40 patients it was demonstrated in six; all had a right upper thoracic mass and four had a superior vena caval syndrome. Coronal magnetic resonance, images (MRI) of the thorax were superior to all other imaging methods in demonstrating the nipple. It is concluded that in patients with masses in the right upper chest, coronal MR chest examinations are valuable in demonstrating an aortic nipple, a sign of impending present superior vena caval or innominate, vein obstruction.  相似文献   
35.
Induction of neurite outgrowth from superior cervical ganglia (SCG) by rat lymphoid tissues was studied using a tissue culture model. Neonatal rat SCG were cultured with 6–12-week-old rat thymus, spleen, or mesenteric lymph node (MLN) explants in a Martrigel layer, in defined culture medium without exogenous nerve growth factor (NGF). SCG were also co-cultured with neonatal rat heart (as positive control) or spinal cord (SC; as negative control). To determine whether inflammation affects the ability of lymphoid tissues to induce neurite outgrowth, we also examined MLN at various times after infecting rats with Nippostrongylus brasiliensis (Nb-MLN). In one series of experiments, a single lymphoid tissue explant was surrounded by four SCG at a distance of 1 mm. The extent of neurite outgrowth was determinded by counting the number of neurites 0.5 mm away from each ganglion at several time points. Adult thymus and, to a lesser extent, spleen had strong stimulatory effects on neurite outgrowth from SCG after 12 hr or more in culture. For thymus tissue, this was similar to the positive control heart explants. MLN from normal rats had minimal effect on neurite outgrowth; however, Nb-MLN showed a time-dependent enhancement of the neurite outgrowth, maximal at 3 weeks after infection. The relative efficacy of neurite outgrowth induction (heart ≥ thymus ≥ Nb-MLN ≥ spleen ≥ MLN ≥ SC) was confirmed in a second series of experiments where one SCG was surrounded by three different tissue explants. We then examined the role of 2.5S NGF, a well-known trophic factor for sympathetic nerves, in the lymphoid tissue-induced neurite outgrowth. Anti-NGF treatment of co-cultures of SCG and heart almost completely blocked the neurite outgrowth. Anti-NGF also significantly inhibited thymus- and spleen-induced neurite outgrowth, but not as effectively as heart-induced neuritogenesis (93,80, and 77% inhibition at 24 hr; 86,70, and 68% inhibition at 48 hr for heart, thymus, and spleen, respectively). On the other hand, anti-NGF inhibited only 8% of neurite outgrowth induced by 3-week post-infection Nb-MLN at 24 hr, and 41% at 48 hr. These data show that several adult rat lymphoid tissues exert neurotrophic/tropic effects. The predominant growth factor in thymus and spleen is NGF, while Nb-MLN produces factor(s) which is (are) immunologically distinguishable from NGF. These neurotrophic/tropic factors are produced during the reactive lymphoid hyperplasia that forms part of the inflammatory response against the nematode, N. brasiliensis. This suggests the possibility that cytokines produced by lymphocytes or other inflammatory cells may stimulate sympathetic neurite outgrowth in vivo. © 1994 Wiley-Liss, Inc.  相似文献   
36.
The distribution of GABA-producing neurons in the brainstem auditory nuclei of the rat was investigated immunohistochemically by using an antibody to glutamic acid decarboxylase (GAD). In the cochlear nuclei, GAD immunoreactive neurons are present only in the superficial granular and molecular layers, whereas terminals are found in all subdivisions of the nuclei and are particularly dense surrounding large spherical cells and one type of stellate cell. In the superior olivary complex, GAD immunoreactive neurons are located in the lateral olivary nucleus and throughout the periolivary region. Immunoreactive terminals are distributed along dendrites of principal cells of the medial and lateral olivary nuclei and are clustered around somata of globular neurons of the nucleus of the trapezoid body. An extremely dense band of immunoreactive somata and terminals is present along the ventral edge of the olivary complex. The ventral, intermediate, and dorsal nuclei of the lateral lemniscus contain small fusiform GAD-immunoreactive neurons and a moderately dense plexus of immunoreactive terminals. The inferior colliculus contains a large population of GAD-immunoreactive perikarya and an extremely dense accumulation of immunoreactive terminals in the central, dorsomedial, and external nuclei. These observations indicate that GABA systems are involved in function at all levels of the brainstem auditory pathway.  相似文献   
37.
人心和山羊心脏上、下腔静脉肌袖大体解剖   总被引:2,自引:2,他引:0  
目的:观测人和山羊上、下腔静脉肌袖结构特点,为治疗局灶性心房颤动积累解剖学资料。方法:采用大体解剖方法观测人心(20例)和羊心(40例)的上、下腔静脉及其表面的心肌纤维。结果:人心上腔静脉肌袖的长和宽分别为(1.91±0.39)cm、(2.41±0.26)cm,下腔静脉肌袖的长和宽分别为(1.32±0.32)cm,(3.06±0.52)cm;羊心上(前)腔静脉肌袖的长和宽分别为(1.41±1.00)cm、(1.05±0.26)cm,下(后)腔静脉肌袖的长和宽分别为(0.81±0.48)cm,(1.03±0.28)cm。人和羊心脏的上腔静脉肌袖出现率均为100%;下腔静脉肌袖的出现率分别为88.89%和98%。肌纤维多数来源于右心房前后壁,也有来自于左心房或左右心房的。结论:①上腔静脉肌袖是人和羊普遍存在的解剖结构,人的下腔静脉肌袖出现率明显低于羊,可能是上腔静脉肌袖引起局灶性心房颤动多于下腔静脉肌袖的解剖学基础。②上腔静脉肌袖是构成左右房的又一重要通路。  相似文献   
38.
Ectopic cervical or cervico-mediastinal thymomas are very rare and most of them are asymptomatic, except for the presence of a cervical mass. We present the case of a 71-year-old man with an ectopic cervico-mediastinal thymoma threatening superior vena cava syndrome. He had a slight headache and presented with venous dilatation on the chest wall. A computed tomographic scan and magnetic resonance, imaging of the chest demonstrated a mass extending from the right neck to the hilum, that indented the trachea and compressed and displaced the brachiocephalic veins anteriorly. Under a right hemicollar incision and median sternotomy, the mass was resected en bloc together with the thymus. The resected specimen was an encapsulated mass measuring 11×7×4 cm. The pathological diagnosis was type AB, non-invasive thymoma, confirmed by 3-color flow, cytometry of tumor-derived lymphocytes. Flow cytometry using biopsy material may contribute to the preoperative diagnosis of ectopic thymoma.  相似文献   
39.
We describe the case of a recipient of an implantable cardioverter defibrillator with multiple syncopal episodes due both to superior vena cava obstruction and electrical instability. These complications occurred in the presence of two transvenous implantable cardioverter defibrillator leads. The patient has been managed conservatively with anticoagulants and new antiarrhythmic drugs with improvement in both his clinical problems.  相似文献   
40.
多层螺旋CT三维重建在左肾静脉压迫综合征中的临床应用   总被引:6,自引:0,他引:6  
目的探讨多层螺旋CT(MSCT)三维重建在左肾静脉压迫综合征中的诊断价值。方法应用16层螺旋CT对11例左肾静脉压迫综合征病例进行泌尿系增强多期扫描,并获得各种后处理图像。结果11例左肾静脉压迫综合征病例均可见肠系膜上动脉(SMA)压迫左肾静脉(LRV)的征象。CT多平面重建(MPR)直观地显示了腹主动脉(AO)与SMA之间的夹角(α),最大为21.88,°最小为12.86°,平均为17.95°。CT横断位图像显示扩张的左肾静脉直径为12~15.3 mm,平均为13.26 mm;LRV受SMA压迫狭窄处直径为3.0~4.0 mm,平均为3.26 mm。左侧卵巢静脉或睾丸静脉直径为2.1~2.6 mm,平均为2.2 mm。5例增强扫描肾实质期(后期)显示双肾实质密度相差20 HU以上。结论MSCT在胡桃夹综合征诊断中具有明显的优势。  相似文献   
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