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991.
BACKGROUND: The treatment of diffuse brain injury during an acute period is focused on relieving degrees of secondary brain injury. Generation and development of pathological changes of secondary brain injury depend on signal conduction, so down-regulating over response of astrocyte through interfering a key link of signal conduction pathway may bring a new thinking for the treatment of diffuse brain injury. OBJECTIVE: To observe the effect of over activity of extracellular signal regulated kinases 1/2 (ERK1/2) signal pathway on the response of astrocyte during an acute period of diffuse brain injury. DESIGN: Completely randomized grouping and controlled animal study. SETTINGS: Department of Neurosurgery, the Third Affiliated Hospital, Nanchang University; Department of Neurosurgery, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: A total of 158 healthy male SD rats, of 11 weeks old, weighing 320–370 g, were provided by Experimental Animal Faulty, Tongji Medical College, Huazhong University of Science and Technology. Rabbit-anti-phosphorylated ERK1/2 (pERK1/2) polyclonal antibody was provided by R&D Company; rabbit-anti-glial fibrillary acidic protein (GFAP) polyclonal antibody, SP immunohistochemical kit and horseradish peroxidase (HRP)-labeled goat-anti-rabbit IgG by Santa Cruz Company; specific inhibitor U0126 of ERK1/2 signal pathway by Alexis Company. METHODS: The experiment was carried out in the Laboratory of Neurosurgery, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology from September 2004 to March 2006. ① Detection of pERK1/2 expression: A total of 110 rats were randomly divided into sham operation group (n =5), model group (n =35), high-dosage U0126 group (n =35) and low-dosage U0126 group (n =35). Rats in the sham operation group were only treated with incision of epicranium and fixation of backup plate, but not hit. Rats in the model group were used to establish diffuse brain injury models based on Marmarou free falling body without drug intervention. Rats in the high- and low-dosage U0126 groups were injected into caudal vein with 0.1 and 0.05 mg/kg U0126, respectively, and then, rats were hit to establish injured models. Every 5 rats were collected from model, high- and low-dosage U0126 groups at 5, 30 minutes, 3, 12, 24, 72 hours and 7 days after diffuse brain injury to detect pERK1/2 expression in cortex of parietal lobe based on Western blot technique. ② Distribution of pERK1/2 and positive GFAP cells in brain tissue: Another 48 rats were randomly divided into sham operation group (n =3), model group (n =15), high-dosage U0126 group (n =15) and low-dosage U0126 group (n =15). The intervention and administration were dealt as the same as those mentioned above. Every 3 rats were collected from model, high- and low-dosage U0126 groups at 30 minutes, 3, 12, 24 and 72 hours after model establishment to observe the distribution of pERK1/2 and postive GFAP cells in brain tissue which was cut from coronal section at Bregma –4.8 mm layer with immunohistochemical staining. MAIN OUTCOME MEASURES: pERK1/2 expression in cortex of parietal lobe and distribution of pERK1/2 and positive GFAP cells in brain tissues. RESULTS: ① pERK1/2 expression: After diffuse brain injury, pERK1/2 expression in cortex of parietal lobe was rapidly increased in the model group, reached at peak at 5 minutes and then decreased gradually. But the expression was still in a high level until the 72nd hour and fallen to the basic level on the 7th day. pERK1/2 level was lower in high- and low-dosage U0126 groups than that in model group at various time points (P < 0.01); meanwhile, pERK1/2 level was lower in high-dosage U0126 group than that in low-dosage U0126 group. The results showed that there was a certain dosage dependence on pERK1/2 expression. ② Distribution of pERK1/2 and positive GFAP cells in brain tissue: Positive expression of pERK1/2 lasted in brain tissue from 30 minutes to 72 hours after diffuse brain injury (P < 0.05). In addition, from 30 minutes to 3 hours, brown-yellow stained cells were mainly distributed in plasma, but rarely in nucleus. A lot of positive cells had tree-like apophysis, which was similar to neurons. With the time passing by, more and more nuclei manifested positive stains; moreover, nuclei mainly manifested positive staining until 24 hours after diffuse brain injury. Immune-positive pERK1/2 cells were widely distributed in brain tissue, especially mainly in binding site between deep cortex and cerebral white matter, and then in hippocampus. In addition, ependymal cell and vascular endothelial cells of choroids plexus also manifested strongly positive staining. As compared with model group, positive cells were decreased gradually in high- and low-dosage U0126 groups. However, number of positive cells was less in high-dosage U0126 group than that in low-dosage U0126 group. CONCLUSION: Diffuse brain injury strongly induces the activity of ERK1/2 signal pathway and response of astrocyte; in addition, U0126 can inhibit response of glial cells during an acute period, and the effect manifests dosage dependence.  相似文献   
992.
Tendon healing is a complex process consisting of a large number of intricate pathways roughly divided into the phases of inflammation, proliferation, and remodeling. Although these processes have been extensively studied at a variety of levels in recent years, there is still much that remains unknown. This study used microarray analyses to investigate the process at a genetic level in healing rat Achilles tendon at 1, 7, and 21 days postinjury, roughly representing the inflammation, proliferation, and remodeling phases. An interesting temporal expression profile was demonstrated, identifying both known and novel genes and pathways involved in the progression of tendon healing. Both inflammatory response and pro-proliferative genes were shown to be significantly upregulated from 24 h postinjury through to 21 days. Day 7 showed the largest increase in genetic activity, particularly with the expression of collagens and other extracellular matrix genes. Interestingly, there was also evidence of central nervous system-like glutamate-based signaling machinery present in tendon cells, as has recently been shown in bone. This type of signaling mechanism has not previously been shown to exist in tendon. Another novel finding from these analyses is that there appears to be several genes upregulated during healing which have exclusively or primarily been characterized as key modulators of proliferation and patterning during embryonic development. This may suggest that similar pathways are employed in wound healing as in the tightly regulated progression of growth and development in the embryo. These results could be of use in designing novel gene-based therapies to increase the efficacy and efficiency of tendon healing.  相似文献   
993.
经尿道前列腺电切术后膀胱颈挛缩多因素分析   总被引:24,自引:2,他引:22  
目的 :对经尿道前列腺电切术 (TURP)后膀胱颈挛缩 (BNC)发生的各种可能因素进行分析 ,探讨减少该并发症的途径。 方法 :对 10 17例行TURP患者中发生BNC的 2 4例进行统计学分析 ,在手术方法、前列腺电切重量、单位时间前列腺组织电切重量、置管时间、高频发生器类型及有无糖尿病、尿潴留及前列腺炎等方面进行比较 ,了解其可能发生的因素。 结果 :TURP术后BNC发生率明显高于开放手术病例 ,小前列腺、单位电切时间长、高频发生器功率大及术前前列腺炎患者易发生BNC(P <0 .0 5 ) ,而术前尿潴留、糖尿病及术后置管时间对BNC发生无明显影响 (P >0 .0 5 )。 结论 :小前列腺、前列腺炎及电流损伤是发生BNC的重要因素 ,患者的选择及熟练精确的电切技术可减少BNC的发生。  相似文献   
994.
目的:评价祛银合剂治疗银屑病的临床疗效,方法:将250例寻常型银屑病患者随机分为两组,分别口服祛银合剂(129例)和复方青黛丸(121例)。3例红皮病型银屑病患者口服祛银合剂治疗。结果:两组总有效率比较有显著性差异(P<0.01);3例红皮病型银屑病均得以治愈。结论:祛银合剂治疗寻常型银屑病疗效确切,未发现副作用,值是临床应用,同时为红皮病型银屑病提供了新的治疗方法。  相似文献   
995.
中药安迪对HL-60细胞分化的诱导作用   总被引:4,自引:1,他引:3  
目的 探讨安迪粉针剂 (Andi)对 HL- 60细胞分化的诱导作用 .方法 采用人早幼粒白血病细胞株 (HL - 60 )为靶细胞 ,分为不加任何药物的对照组 (C组 )、安迪粉针剂 (Andi)组、阳性对照药维甲酸 (RA)组和苦参 (KS)组 ,进行体外培养和诱导分化 ,观测细胞生长曲线、细胞形态、硝基蓝四氮唑(NBT)还原和吞噬能力等指标 .结果  2 mg· L-1 Andi可显著地抑制 HL - 60细胞增殖 ,使原始细胞分化为中幼以下的成熟细胞 ,分化后的细胞具有 NBT还原能力和吞噬功能 ;Andi为 68.0 % ,RA为 61 .5% ,KS为 59.0 % ,C组还原能力仅6.0 % (P<0 .0 1 vs C) .其形态的改变和吞噬能力与阳性对照药维甲酸 (RA)和苦参 (KS)相似 ,分别为 52 .0 % ,45.5%和56.5% (P>0 .0 5) ;均明显高于空白对照组 .C组吞噬功能仅7.5% (P <0 .0 1 vs C)其 NBT还原能力与 KS相当 (P >0 .0 5) .结论  Andi对 HL - 60细胞具有显著的诱导分化作用  相似文献   
996.
It has been suggested that reward dependence, as measured by the Tridimensional Personality Questionnaire (TPQ), is related to central noradrenergic activity, a proposition supported by two studies of urinary norepinephrine metabolite. In the current investigation, 190 normal young Han Chinese were examined, with genetic polymorphisms determined for the norepinephrine transporter (1287G/A) and the α2c‐adrenoceptor (Del322–325) to test the association with TPQ personality traits. No significant association was demonstrated for these two polymorphisms and any of the TPQ personality‐factor scores, including reward dependence and its subscales. Our negative findings suggest that the investigated polymorphisms of the norepinephrine transporter and the α2c adrenoceptor do not play a major role in the reward‐dependence personality trait as assessed by TPQ. © 2002 Wiley‐Liss, Inc.  相似文献   
997.
目的 :探讨SARS患者外周血T淋巴细胞亚群变化。方法 :采用流式细胞仪检测10 0例SARS住院患者外周血T淋巴细胞亚群。结果 :与正常组比较 ,SARS组白细胞总数显著下降 ,淋巴细胞百分数和绝对数显著下降 ,粒细胞绝对数显著下降 ,CD3 、CD4 、CD8 细胞绝对数显著下降 ,CD4 细胞百分数 ,CD8 细胞百分数及CD4 /CD8 比值差异无统计学意义。比较SARS患者各病程CD3 、CD4 、CD8 ,于病程第一至第三周较第四周下降明显 (P <0 .0 5 ) ,病程第一至第三周之间差别无显著性 (P >0 .0 5 ) ;结论 :SARS患者外周血T淋巴细胞亚群的变化对阐明SARS的发病机制有一定意义。  相似文献   
998.
目的探讨肘、膝、踝关节内外翻畸形的治疗方式。方法对55例8~16岁的关节内、外翻畸形患儿(肘关节30例,膝15例,踝10例),采用肘外侧切口,踝、膝内外侧切口,截骨矫形,1枚或2枚“∩”形钉内崮定治疗,术后石膏托外固定4周,结果随访50例,随访时间3~24个月,截骨均达到骨性愈合,无一例发生感染,内固定松动临床疗效优48例(96%),良2例(4%)。结论用“∩”形钉作为截骨矫形内固定材料.具有操作简单、损伤小、效果好的优点。  相似文献   
999.
为比较宫腔镜辅助下分段诊刮术与单纯分段诊刮术在诊断子宫内膜癌中的临床意义 ,将经手术后病理证实的子宫内膜癌患者分为 2组 :宫腔镜辅助下分段诊刮组 (A组 ) 3 1例 ;单纯分段诊刮组 (B组 ) 3 9例。比较 2组术前诊断子宫内膜癌的准确性及开腹手术时腹水细胞学的检查结果。 2组患者的年龄、临床病理分期、病理分级及组织学类型差异无显著性。A组诊断宫颈受累的准确率为 96.77% (3 0 / 3 1 ) ,假阳性率为 3 .2 3 % (1 / 3 1 ) ;B组分别为 79.49%(3 1 / 3 9) ,1 5 .3 8% (6/ 3 9)。 2组准确率比较 ,差异有显著性 (P <0 .0 5 )。取腹水或腹腔冲洗液行细胞学检查。A组细胞学阳性率为 6.45 % (2 / 3 1 ) ,B组为 1 4.2 9% (3 / 2 1 ) ,2组间差异无显著性 (P >0 .0 5 )。提示 :宫腔镜辅助下分段诊刮术可提高术前诊断子宫内膜癌的准确性 ,从而避免不必要地扩大手术范围 ,而且不增加腹腔内播散的危险。  相似文献   
1000.
双侧内囊前肢毁损术治疗难治性强迫症疗效及随访研究   总被引:9,自引:0,他引:9  
目的 对难治性强迫症进行双侧内囊前肢毁损术治疗 ,评定手术疗效并进行 2年随访 ,以进一步探索脑外科手术对难治性强迫症的疗效 ,并探讨手术治疗的良好适应症。方法 对 2 8例难治性强迫症患者进行双侧内囊前肢毁损术治疗 ,并分别在手术前、手术后二周、手术后三月、手术后六月、手术后一年、手术后二年进行Y BOCS、HAMA、HAMD量表评定及术后疗效评定。结果  (1)强迫症患者手术后各期Y BOCS评分、HAMA评分与手术前比较均下降 ,有极显著差异 (P <0 .0 0 1) ;(2 )手术后各期Y BOCS的强迫思维评分均有明显下降 (P <0 .0 0 1) ,强迫行为在手术后 1年和 2年 ,与手术前比较无明显改变 (P >0 .0 5 ) ;(3)手术后 2年的总有效率为 5 3.5 % ,明显低于手术后 3月的总有效率 (P <0 .0 1)。结论 采用双侧内囊毁损术有相当的治疗效果 ,对于难治性强迫症患者可作为一种补充治疗手段 ;手术治疗对强迫行为的长期疗效较差 ,以严重的强迫思维为主的难治性强迫症患者为手术更好的适应症。  相似文献   
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