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61.
增强子Ⅰ对乙型肝炎病毒DNA疫苗免疫应答的影响   总被引:1,自引:0,他引:1  
目的研究乙型肝炎病毒(HBV)自身增强子Ⅰ(enhancerⅠ,ENHⅠ)对HBVDNA疫苗免疫应答的影响。方法采用PCR法以HBVadr亚型全基因DNA序列为模板分别扩增表面抗原(HBsAg)和HBsAg-ENHⅠ基因片段,重组到载体VR1012中,构建两种HBVDNA疫苗,转染COS-7细胞及HepG2细胞并免疫BALB/c小鼠。采用蛋白印迹、ELISA、ELISPOT等方法检测其在COS-7和HepG2细胞内的表达及小鼠的体液及细胞免疫应答效果。结果转染的HepG2和COS-7细胞均表达HBsAg;连接ENHⅠ的HBVDNA疫苗转染HepG2细胞后HBsAg表达量明显升高,两种疫苗转染COS-7细胞表达HBsAg无明显差异;免疫小鼠后第2周产生HBsAb及HBsAg特异性细胞毒T淋巴细胞(CTL),两种疫苗免疫产生的HBsAb及HBsAg特异性CTL无明显差异。结论ENHⅠ可使HBVDNA疫苗转染HepG2细胞表达HBsAg明显增加,对转染COS-7细胞表达HBsAg及接种BALB/c小鼠引起的免疫应答无明显影响。  相似文献   
62.
腹腔镜辅助中位肛门闭锁成形术11例报告   总被引:3,自引:1,他引:2  
目的 探讨腹腔镜辅助中位肛门闭锁成形术的可行性。方法 腹腔镜监视下,游离松解直肠;断离修补直肠尿道(阴道)瘘管,其中6例经腹腔镜离断修补,4例经会阴切口离断修补;然后在电刺激仪的引导下经会阴肌肉中心1.0cm左右小切口向盆底肌肉中心分离形成隧道,最后将直肠从隧道中拖出,与会阴皮肤吻合,同时关闭结肠造瘘口。结果 11例患儿均在腹腔镜辅助下完成肛门成形术,腹腔镜手术操作时间平均32.8min(25~78min),出血量平均5.3ml(2~10ml),无需要输血者。术后11d去除尿管或膀胱造瘘管,无尿道瘘或憩室出现,无切口感染发生。11例术后随访3~66个月,平均45个月。根据肛门功能临床评分标准评分(6分法),排便优8例(72.7%),良3例(27.3%)。结论 腹腔镜辅助中位肛门闭锁成形术处理直肠泌尿系瘘方便,辨认盆底肌中心准确及避免切口污染等优点,是治疗中位肛门闭锁有效方法。  相似文献   
63.
OBJECTIVE: To examine health care seeking pathways for patients with tuberculosis (TB) and barriers related to these pathways in counties under the National TB Control Programme in rural China. METHODS: A cross-sectional study was conducted in two counties of east China in 2004-2005. A total of 557 TB patients were recruited and interviewed by physicians at the time of TB diagnosis. RESULTS: Of 557 participants, 13.3% had presented to a specialised county TB dispensary (CTD) directly after onset of symptoms, 31.4% had first sought care at a village health station and 51.2% had visited a township or county hospital first. The proportion of referral by a first health care provider to a CTD was highest in county level hospitals (73.5%) and lowest in village health stations (21.7%). The most prompt pathway from first health care seeking to TB diagnosis was to visit a CTD directly, with a median provider's delay of only one day. There was an increase in provider's delay when more health facilities were involved. CONCLUSION: To improve direct referral from general health care providers, especially village health care workers, to TB specialists would significantly shorten the delays in TB diagnosis in rural China.  相似文献   
64.
Neurochemical studies on the mesolimbic circuitry of antinociception   总被引:1,自引:0,他引:1  
Previous studies using the technique of microinjection into brain nuclei indicated that the periaqueductal gray (PAG), nucleus accumbens, habenula and amygdala play an essential role in pain modulation and that these nuclei possibly act through a ‘mesolimbic neural loop‘ to exert an analgesic effect, in which Met-enkephalin (MEK) and β-endorphin (β-EP) have been implicated as the two major opioid peptides involved in antinociception. In the present study performed in rabbits, intracranial microinjection was supplemented with push-pull perfusion and radioimmunoassay to determine whether the release of enkephalins (ENK) and β-EP was increased in these nuclei when the putative neural circuit was activated by morphine administered into one of the nuclei. The results showed: (1) microinjection of morphine into the PAG increased the release of ENK and β-EP in the N. accumbens, and vice versa; (2) microinjection of morphine into the N. accumbens increased the release of ENK and β-EP in the amygdala, and vice versa; (3) morphine microinjected into the PAG caused an increase in the release of ENK and β-EP in the amygdala and vice versa, although the release of ENK in PAG was statistically not significant. These results indicate that PAG, N. accumbens and amygdala are connected in a network served by a positive feedback circuitry.  相似文献   
65.
This paper is a summary of our observations on 105 cases of infantile spasms. The age of onset was around six months after birth, but the patients came for treatment mainly about one year after onset. Fever of unknown cause, asphyxia, birth injury, infection of the central nervous system, tuberous sclerosis, phenylketonuria and recent immunization etc. were complained. Clinically, it is characterized by head nodding, mental retardation, myoclonic jerks and various neurologic deficits. EEG findings showed classical or modified arrythmia or other epileptiform patterns. About one third of 22 cases examined had abnormal brain stem auditory evoked potentials. Among 42 patients who underwent CT scanning before ACTH treatment, 18 were normal and 7 abnormal; during ACTH treatment 3 normal and 4 abnormal; after completion of treatment, 4 normal and 6 abnormal, suggesting no further atrophy of the brain. Examination of trace elements of the hair by particle-induced X-ray emission (PIXE) method in 23 patients revealed a significant difference in lead, calcium and zinc contents between patients and 101 controls, but no statistical difference in iron and copper contents between the two groups. Sodium valproate, prednisone and ACTH appear to be effective in the treatment of infantile spasms. Eight patients fully recovered, and they can go to school without difficulty. Many patients derived various degrees of improvement to the satisfaction of their parents. Two patients were still amented and often attacked by myoclonus. The effects, side effects of these drugs, and the possible pathogenesis were discussed.
  相似文献   
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目的:建立类风湿关节炎伴发抑郁症动物模型。方法:以复合造模思路,在采用胶原诱导复制大鼠类风湿关节炎模型基础上,结合孤养法和慢性不可预知的温和应激方法,造成类风湿关节炎伴发抑郁症动物模型。结果:造模后给予行为学测试和下丘脑5-HT、5-HIAA含量测定,模型组大鼠踝关节肿大畸形,关节炎指数增高,蔗糖水饮用量、旷野试验中水平及垂直得分、下丘脑5-HT、5-HIAA含量都明显小于正常组,有非常显著性差异(P〈0.01)。结论:类风湿关节炎伴发抑郁症动物模型关节肿大畸形,关节炎指数增高,呈抑郁状态,兴趣丧失,快感缺乏,运动迟滞等,能充分模拟类风湿关节炎伴发抑郁患者的核心症状,实验重复性较好,是研究类风湿关节炎伴发抑郁的理想模型。  相似文献   
68.
OBJECTIVE: The C2A domain of Synaptotagmin I is a molecular probe for the specific imaging of cell death. Here we test the hypothesis that the uptake of 99mTc-C2A in the acute phase of an infarction is associated with cardiac dysfunction in follow-ups. METHODS: The left coronary artery was occluded in Sprague-Dawley rats for 0, 10, 20, and 30 min. 99mTc-C2A was injected intravenously at 2 h of reperfusion. Anterior planar images were acquired with one million counts on a gamma camera 3 h after injection. 99mTc-C2A uptake was calculated as the total counts in the left ventricle region minus blood pool signal. The in-vivo signal detected was correlated with wall motion score index at 1 and 3 weeks follow-ups measured by echocardiography. RESULTS: 99mTc-C2A uptake was higher with increased ischemic time (2244+/-852, 4054+/-1223, and 6178+/-1451 for 10, 20, and 30 min ischemia, analysis of variance P<0.001). A significant correlation was found between 99mTc-C2A uptake and wall motion score index at 1 week (R=0.800, P=0.0006) and 3 weeks (R=0.810, P=0.0008). CONCLUSION: In this ischemia/reperfusion model, 99mTc-C2A uptake in the acute phase was associated with functional abnormality at 1 and 3 weeks. This demonstrates the potential diagnostic and prognostic value of 99mTc-C2A as a novel imaging agent.  相似文献   
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