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51.
OBJECTIVE: To study the expression of neuron-specific enolase (NSE) and olfactory marker protein (OMP) in the developing olfactory mucosa of human fetuses. METHOD: The expression of NSE and OMP in the olfactory mucosa of 6 human fetuses (12, 16, 20, 24, 28 and 34 weeks) was studied using the technique of immunohistochemistry. RESULTS: NSE immunological positive reactions were seen in all 6 fetal mucosa from gestational 12 (G12) to G34, with plenty of positive-stained dual-pole neuron cells. At G12, the positive cells aligned tightly, the cell bodies were localized in the lower portion of olfactory epithelium and the positive-stained area occupied upper 2/3 of fetal nasal mucosa. With the development, the positive cells gradually became multilayer, but the density and the relative area of positive-cells reduced. At G34, the positive cells were located only in upper 1/3 of nasal mucosa. OMP-positive reactions were localized in a few dual-pole neurons at G12, the number was much less than NSE-positive cells in the same fetus. With the development, the OMP-positive cells gradually increased with most of the cell bodies located in the upper portion of epithelium, but number still relatively less than the NSE-positive cells at the same age. CONCLUSION: At G12, there were lots of olfactory neuron in the olfactory mucosa and only a few olfactory neurons had became mature. With the development, the olfactory epithelial area reduced but the number of mature olfactory neurons increased. At the last trimester, fetal olfactory sensor was almost matured.  相似文献   
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OBJECTIVES: Brain edema occurs following clinical as well as experimental cardiac arrest (CA) and predicts a poor neurologic outcome. The objective of this study was to determine the expression of cerebral cortex aquaporin (AQP)-4, a member of a family of membrane water-channel proteins, in brain edema formation following normothermic or hypothermic CA. METHODS: Twenty-four rats were subjected to time-matched normothermic (N-Sham, 37.5 degrees C +/- 0.5 degrees C, n = 6) or hypothermic (H-Sham, 34 degrees C +/- 0.5 degrees C, n = 6) sham experiments and normothermic (N-CA, n = 6) or hypothermic (H-CA, n = 6) CA induced by asphyxiation for 8 minutes. Hypothermia was induced before CA. The animals were resuscitated with cardiopulmonary resuscitation, ventilation, and epinephrine administration. Brain edema was determined by brain wet-to-dry weight ratio at one hour of resuscitation. AQP4 immunoactivity in the cerebral cortex was determined using immunohistochemical staining and was semiquantified as an intensity of staining with an automated cell imaging system. RESULTS: Mild hypothermia in the sham experiments did not alter cerebral cortex AQP4 immunoactivity (mean +/- SD) (55.0 +/- 3.7 in H-Sham vs. 53.3 +/- 1.7 in N-Sham, p > 0.05). N-CA resulted in a significant increase in AQP4 immunoactivity (61.8 +/- 4.5) compared with N-Sham (p = 0.01) and H-Sham (p = 0.03). H-CA attenuated AQP4 compared with N-CA (53.4 +/- 1.3, p = 0.01). Brain wet-to-dry weight ratios were 4.41 +/- 0.07 in N-Sham, 4.40 +/- 0.08 in H-Sham (p > 0.05 vs. N-Sham), 4.55 +/- 0.04 in N-CA (p = 0.004 vs. N-Sham; p = 0.005 vs. H-Sham), and 4.43 +/- 0.09 in H-CA (p = 0.02 vs. N-CA; p > 0.05 vs. N-Sham and H-Sham). CONCLUSIONS: Cerebral cortical AQP4 expression is up-regulated after normothermic CA, which is attenuated by hypothermia induced before CA.  相似文献   
54.
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe. OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats. DESIGN: Observational contrast animal study. SETTING: Beijing Neurosurgical Institute. MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan. METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue. RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES. CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe.  相似文献   
55.
在制备了两个Cell Ⅰ-Hep Ⅱ 双结构域重组FN多肽(CH50和CH56)的基础上,研究其抑制肿瘤细胞浸润能力的作用。两个多肽的结构差异是CH50中删除了Cell I和HepⅡ之间的Ⅲ-11和ED-A结构顺序。CH50(ED_(50)为30.2 nmol/L)结合细胞的能力略高于CH56(ED_(50)为45.4 nmol/L)。两种多肽均可显著抑制黑色素瘤B16/F1细胞结合层粘素的能力,抑制作用相同。在体内肿瘤浸润抑制试验中,两种多肽均可显著抑制癌细胞浸润能力,使肺转移结节数降低80%左右。结果提示:Ⅲ-11和ED-A结构顺序对Cell Ⅰ-Hep Ⅱ 双结构域多肽结合细胞的能力有一定的影响,但删除Ⅲ-11和ED-A不是重组多肽抑制肿瘤转移的决定因素,Cell I和Hep Ⅱ 这两个结构域单独连接在一起是其抑制肿瘤细胞转移的结构基础。  相似文献   
56.
本文对44例牙源性脓肿(尖周脓肿24例,牙周脓肿12例,冠周脓肿8例)脓液标本中的产黑色素类杆菌群菌株进行分离、培养、鉴定。其中38例存在产黑菌群,以中间型类杆菌阳性率最高。牙龈类杆菌在牙周脓肿中检出率最高。24例尖周脓肿可分离出6株牙髓类杆菌而其它两种牙源性脓肿则无牙髓类杆菌,推测该菌与牙髓尖周感染的病理过程有关。  相似文献   
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This study examines the possible beneficial effect of Re-LPS (F515) antiserum on experimental multiple system organ failure (MSOF) in rabbits. The results showed that the plasma LPS level was significantly decreased, and it took a shorter period to clear up LPS in experimental than in control rabbits after receiving Re-LPS antiserum. Pretreatment with antiserum can markedly improve the function of the liver, lungs, kidneys, blood and gastrointestinal tract. The MSOF incidence in the group of rabbits receiving immune sera was only 11.2% and the survival rate was raised by about 40.0%. The results suggest that early passive immunotherapy may neutralize gut-derived endotoxin, inhibit endotoxin-induced mediators release and prevent development of severe complications due to sepsis. It is therefore postulated that LPS core antiserum may provide a prophylactic effect on the development of experimental MSOF.
  相似文献   
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神经梅毒的临床特征与诊断分析   总被引:34,自引:2,他引:32  
目的:分析神经梅毒的分型和临床特征及提供早期诊断依据。方法:回顾性分析经临床和实验室检查确诊的18例神经梅毒病人的有关临床资料。结果:神经梅毒的临床特征包括:(1)急性、亚急性起病为主;(2)临床以间质型,尤其是以脑卒中起病常见,症状元特异性;(3)血清学检查以梅毒螺旋体血凝试验(TPHA)及快速血浆反应素试验(RPR)特异性较高;(4)脑脊液检查表现为压力增高(42.9%)、蛋白增高(81.2%)及细胞数增高(56.3%);(5)头颅CT、MRI表现与高血压、动脉硬化所致脑梗死不同,为多发、散在病灶。结论:神经梅毒早期误诊率高,临床表现与分型密切相关,实验室及影像学检查是诊断的重要依据。  相似文献   
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