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21.
目的:探讨支气管哮喘患者CD8+T细胞对单核/巨噬细胞抗原递呈功能的影响。方法:哮喘患者20例,健康对照22例,分别取静脉血5 mL,并分离MΦ、CD8+T细胞和B细胞。每份血样分成4组:MΦ递呈抗原组、CD8+T细胞参与MΦ递呈抗原组、CD8+T细胞体外活化后对MΦ递呈抗原影响组及自然状态下CD8+T细胞对MΦ细胞递呈抗原影响组。各组用CTLL2P抗原刺激18 h后,洗去刺激原,与自体B细胞共同孵育10 d,吸取上清液,测定特异性IgM、IgE、IgG含量。 结果:①哮喘患者MΦ单独递呈抗原,自体B细胞特异性IgM(A490值)(0.034±0.022)明显低于健康人(0.116±0.080)(P<0.05);CD8+T细胞与MΦ共同培养递呈抗原时,产生的特异性IgM(A490值)(0.031±0.021)低于健康人(0.079±0.064)(P<0.05);②哮喘患者CD8+T细胞与MΦ共同培养递呈抗原时,产生的特异性IgG(A490值)(0.102±0.041)明显高于健康人(0.081±0.067)(P<0.05),自然状态下及体外活化后CD8+T细胞与递呈抗原MΦ共同培养,产生的特异性IgG(A490值)(0.105±0.066, 0.079±0.059)与健康人(0.066±0.038, 0.069±0.047)无明显差别(P>0.05);③哮喘患者CD8+T细胞与MΦ共同培养递呈抗原产生的特异性IgE(A490值)(0.171±0.154)高于健康人(0.147±0.059)(P<0.05)。 结论:哮喘患者CD8+T细胞对MΦ递呈抗原产生免疫球蛋白有调节作用,而且参与哮喘发病。  相似文献   
22.
脾脏切除对胸腺和淋巴结免疫功能的影响   总被引:4,自引:0,他引:4  
报道脾脏切除(脾切)对动物胸腺和淋巴结免疫功能的影响,脾切后3w大鼠胸腺细胞自发增殖及ConA诱导增殖均无明显变化,ConA诱导淋巴结细胞增殖脾切组明显高于假手术对照组,脾切后3w再用SRBC免疫,5d后小鼠腹腔淋巴结数量脾切明显高于对照组,用QHS法测定淋巴结细胞对SRBC初次抗体产生脾切组则明显低于对照组。  相似文献   
23.
瘤体骨切除灭活再植治疗四肢长骨巨细胞瘤   总被引:21,自引:0,他引:21  
体内刮除及灭活植骨治疗骨巨细胞瘤(GCT)的复发率高。我科从1986年6月~1996年2月治疗四肢长骨GCT24例。随访11个月~8年4个月。其中7例采用局部切刮体内灭活植骨和(或)骨水泥充填治疗。结果1例感染,6例复发,1例恶变后死于肺转移。作者自1991年1月采用瘤体骨切除,离体灭活再植,与骨残端体内灭活相结合,骨缺损采用自家腓、髂骨移植,L-梯形加压钢板(L-TCP)或梯形加压钢板(TCP)固定治疗17例,其中12例保留关节,5例做膝关节融合。本组无菌创口感染1例,1例复发。在保留关节的12例中9例关节功能恢复优良,1例尚可,2例差。充分说明瘤段骨切除体外灭活再植术疗效确实,复发率低。保留关节术式适于关节破坏较轻(<=1/2)者,结合关节残端体内灭活和有效的骨结构重建,有利于恢复关节功能。如关节面累及>1/2,宜做骨关节端切除,灭活再植,下肢宜做关节融合或人工关节置换术。  相似文献   
24.
糖尿病雄性大鼠性腺5α-还原酶Ⅱ型活性变化   总被引:5,自引:0,他引:5  
目的 :探讨大鼠青春期和成年期糖尿病时性腺 5α 还原酶Ⅱ型的活性变化。 方法 :取 4 0d和 90d龄雄性Wistar大鼠各 30只 ,分别分为对照组 (C)、糖尿病组 (D)和胰岛素治疗糖尿病组 (ID)。采用薄层层析法测定各组附睾头、附睾尾、前列腺和睾丸组织内 5α 还原酶 Ⅱ型的活性。 结果 :①青春期大鼠性腺的各部位内 ,5α 还原酶 Ⅱ 型的活性D组均明显低于C组 (P <0 .0 1) ,而ID组明显高于D组 (P <0 .0 1) ;②成年期大鼠性腺的各部位内 ,5α 还原酶 Ⅱ型的活性在C、D和ID组各组间差异无显著性 (P均 >0 .0 5 )。 结论 :青春期大鼠性腺内 5α 还原酶 Ⅱ型的活性更易受代谢环境、激素水平及局部特异性因素的影响 ,而成年期大鼠性腺内 5α 还原酶Ⅱ 型的活性相对稳定  相似文献   
25.
Objective: To study the changes in 5α-reductase type Ⅱactivity in sex glands of pubertal and adult male rats with diabetes. Methods: Pubertal (40 days old) and adult (90 days old) male Wistar rats were used, 30 animals in each group. Each group was randomly divided into 3 subgroups: the control (C), the diabetic (D) and the diabetic with insulin replacement (ID). The activity of 5α-reductase type Ⅱ was determined with thin layer chromatography in the epididymis, prostate and testis. Results: (1) In all the sex glands of pubertal rats, the enzyme activity was significantly lower in group D than in groups C and ID. (2) In all the sex glands of adult rats, there was no significant difference in the activity. Conclusion: In male rats, the activity of 5αa-reductase type Ⅱ in sex glands is more vulnerable to diabetes in pubertal rats than in adult rats.  相似文献   
26.
With the development of interventional therapy, it is necessary for evaluating cerebral vessels to instruct treatment and determine prognosis of patients with ischemic stroke; however, correlation of distribution of infarction focus and clinical symptoms with degrees of cerebrovasoular stricture is still unclear.OBJECTIVE: To evaluate the characteristics of cerebral arterial stricture of patients with ischemic stroke with transcranial Doppler (TCD) and color duplex flow imaging (CDFI) and compare the correlation between distribution of cerebral infarction focus and clinical types with magnetic resonance imaging (MRI).DESIGN: Contrast observation.SETTING: Department of Neurology, the First Hospital of Jilin University.PARTICIPANTS: A total of 159 patients with ischemic stroke were selected from the Department of Neurology, the First Hospital of Jilin University from January to December 2005, including 106 males and 53 females aged from 27 to 88 years. Bases on diagnostic criteria of cerebrovascular disease established by Rao et al, clinical manifestations of all patients were evaluated with CT or nuclear magnetic resonance. All patients provided the confirmed consent.METHODS: The accepted patients received TCD and CDFI examination at 1 week after onset of ischemic stroke. Among them, 112 patients received cerebrovascular imaging examination simultaneously. MRI was used to check cerebral infarction focus and cerebrovascular stricture > 50% was regarded as the accepted vessels. In addition, DWI-T2 TCD (Germany) was used to check middle cerebral artery, and degrees of middle cerebral artery were classified into mild, moderate and severe stricture based on blood velocity (140 cm/s,180 cm/s). Stroke was classified based on characteristics of infarction focus and clinical symptoms showed with MRI and correlation with degrees of cerebrovascular stricture was analyzed simultaneously.MAIN OUTCOME MEASURES: Correlation between the characteristics of ischemic stroke and clinical symptoms checked with TCD and CDFI.RESULTS: A total of 159 patients with ischemic stroke were involved in the final analysis; in addition, 112 oases received cerebrovascular imaging examination simultaneously. ① MRI results of 159 patients with cerebral artery occlusive disease (CAOD): There were 131 patients (82.3%) with cerebral infarction, 40 (25.2%)with transient ischemic attack and 4 (2.5%) with subclavian steal syndrome (SSS). ② Infarction types with MRI examination: There were 33 patients (20.8%) with solitary cerebral infarction and 98 (61.6%) with multiple-cerebral infarction. ③ Results of TCD, CDFI, MRI angiography, CT angiography and digital subtraction angiography (DSA): Among 112 patients, 181 lesion sites (61 .8%) were located in cranium and 112 lesion sites were located out of cranium; especially, lesion site was mostly observed in stem of middle cerebral artery (31.2%) and watershed of basilar artery (7.2%) in cranium and the beginning site of internal carotid artery (21 .4%) out of cranium. ④ Correlation of vascular stricture checking with TCD, MRI and clinical diagnosis: On one hand, MRI and clinical diagnosis demonstrated that 68 patients had a watershed infarction; meanwhile,TCD examination indicated that there were 3 patients with mild vascular stricture, 24 with moderate vascular stricture and 36 with severe vascular stricture. On the other hand, among 68 patients with non-watershed infarction, there were 27 patient with mild vascular stricture, 26 with moderate vascular stricture and 15 with severe vascular stricture. There were significant differences (x2 =26.854, P =0.001 ). Clinical diagnosis indicated that 40 patients had transient ischemic attack and TCD examination demonstrated that there were 8 patient with mild vascular stricture, 12 with moderate vascular stricture and 20 with severe vascular stricture. There were significant differences as compared with 68 patients with watershed infarction (x2 =21.258, P =0.001). ⑤Correlation of vascular stricture checking with CDFI, MRI and clinical diagnosis: On one hand, among patients who were determined as watershed infarction with MRI and clinical diagnosis, CDFI examination indicated that there were 32 patients with mild vascular stricture at neck, 25 with moderate vascular stricture and 6 with severe vascular stricture. On the other hand, among patients with non-watershed infarction, there were 48 patient with mild vascular stricture, 18 with moderate vascular stricture and 2 with severe vascular stricture.There were significant differences (x2 =6.018, P =0.019). Among patients with transient ischemic attack checking with clinical diagnosis, there were 23 patient with mild vascular stricture, 9 with moderate vascular stricture and 8 with severe vascular stricture. There were no significant differences as compared with patients with non-watershed infarction (x2 =0.597, P=0.440).CONCLUSION: ① TCD and CDFI are effective marks to determine cerebral arterial stricture and hemodynamical changes. ② Infarction and transient ischemic attack at watershed are generally clinical phenotypes of CAOD patients and infarction at watershed is correlated with degrees of cerebrovascular stricture.③ TCD, MRI and clinical analysis of stroke types are significant for instructing treatment and evaluate prognosis.  相似文献   
27.
目的 探讨侧脑室内脑膜瘤诊断特点及显微手术方法.方法 MRI和/或CT确诊并行显微手术切除侧脑室脑膜瘤24例,其中2例内窥镜辅助切除.肿瘤位于左侧三角区13例,右侧三角区7例,右侧体部1例,横跨双侧三角区1例,左侧颞角2例.顶枕入路15例,颞中回入路7例,经胼胝体后部入路2例.结果 24例影像学诊断与术后病理相符合,均给予全切.完整切除5例,分块切除19例.18例获得随访,完全正常10例,3例复发再次手术全切,癫痫2例,同向性偏盲3例.结论 CT和MRI是诊断侧脑室脑膜瘤的最可靠的手段,显微手术是目前侧脑室脑膜瘤的首选治疗方法.  相似文献   
28.
长骨肿瘤切除后节段性骨缺损的一期骨关节重建   总被引:4,自引:0,他引:4  
作者采用瘤段骨切除1.灭活再植,自家或同种异体腓骨髓内移植,或加松质骨髓内移植,梯形或L-梯形钢板(TCP或L-TCP)固定;2.保留骨骺或关节骨壳,自家或同种异体节段皮质骨,或加松质骨移植,TCP或L-TCP固定;3.同种异体骨及全髁膝关节假体置换,自家腓骨及髂骨髓内移植,TCP固定;4.全桡骨切除,自家腓骨移植。治疗骨肉瘤18例,巨细胞瘤10例,侵袭大或复发的骨纤维异样增殖症19例21个骨。共47例49个骨,50次手术。骨缺损长度7.8~23.5cm,平均14.4cm。随访18个月~8年4个月者43例45个骨,46次手术。术后感染4例5次(8.5%);2例并发骨不连及应力骨折而失败,其中1例截肢。其余再植骨及移植骨均与宿主骨一次手术愈合(95.6%)。骨不连和疲劳骨折的发生率分别为4.3%(2例)及6.5%(3例)。作者强调从生物学和机械力学两方面考虑,对节段性骨缺损采用一期骨关节重建的术式治疗,有利骨愈合和恢复功能,减少复发和骨不连,疲劳骨折等并发症。  相似文献   
29.
目的 探讨银杏叶提取物(EGb)对宫内缺氧新生大鼠急性脑缺血损伤的保护作用。方法 夹闭妊娠大鼠子宫血管,制成急性脑缺血损伤新生鼠模型,治疗组给予腹腔注射EGb,在生后不同时间比较两组仔鼠脑组织含水量、NO的变化,神经型一氧化氮合酶(nNOS)的表达及神经细胞凋亡情况变化。结果 急性脑缺血后,脑组织含水量明显增加,NO的含量迅速上升,同时凋亡细胞数增加,两者成直线正相关。EGb治疗后NO含量显著低于未治疗组,同时观察到治疗组的nNOS表达明显降低,凋亡细胞数量减少。结论EGb对急性缺血引起的脑损伤有保护作用。  相似文献   
30.
目的:观察糖基化终末产物(AGEs)对大鼠肾系膜细胞纤溶酶原激活物抑制物-1(PAI-1)表达的影响及其与细胞外基质(ECM)成分含量的关系。方法:体外培养正常大鼠肾系膜细胞,分别用糖化牛血清白蛋白(AGEs)及未经糖化的牛血清白蛋白(BSA)处理,以常规培养的肾系膜细胞作为对照,检测不同时间、不同浓度AGEs对纤维连接蛋白(FN)、Ⅳ型胶原、PAI-1表达的影响。MTT法检测AGEs对系膜细胞增殖的作用,ELISA测定条件培养基中FN、Ⅳ型胶原及PAI-1蛋白含量,逆转录聚合酶链式反应(RT—PCR)检测系膜细胞PAI-1 mRNA的表达。结果:与相应浓度的BSA比较,AGEs(0—200mg/L)对系膜细胞增殖无明显影响,但可不同程度地刺激系膜细胞FN、Ⅳ型胶原、PAI-1蛋白的产生。RT—PCR检测显示,给予AGEs(100mg/L)的系膜细胞PAI-1 mRNA的表达明显增加(P〈0.01)。结论:AGEs促进系膜细胞PAI—1的表达,提示AGEs通过上调PAI-1的表达而减少细胞外基质降解,可能是糖尿病肾病细胞外基质积聚的原因之一。  相似文献   
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