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61.
用多粘菌素B琼脂糖亲和层析法清除内毒素,结果表明:5ml多粘菌素B层析柱的总吸附内毒素能力为450 μg,用此法可完全清除体液或各种液体中的内毒素,对血清及腹水中的内毒素也有明显的吸附作用,而其他各种主要成分(除内毒素外)经过处理后无明显改变。去氧胆酸是一种强有力的去污剂,可使已饱和的柱子复活,复活率达85%左右。该方法有简便,可靠,吸附能力大,柱子的复活率高等优点。本方法的建立为内毒素血症的治疗展示了新的前景。 相似文献
62.
Zheng Qi-xin Zhu Tong-bai Du Jing-yuan Hong Guang-xiang Li Shi-pu Yan Yun-hua Zhang En-dang 《华中科技大学学报(医学英德文版)》1992,12(3):173-178
Summary The authors have prepared the artificial bone of porous tricalcium phosphate ceramics according to an appropriate formula
and manufacturing technology. Physical and chemical testing shows that it possesses several distinguishing features: the communicating
pores and macro/micropores; mean pore size, 380 μm (from 240 μm to 510 μm); porosity, 46.4 %; and compressive strength, 97.4
kg/cm2. It consists of CaO (49.09 %) and P2O5 (48.84 %). The testing of its biocompatibility shows that it is devoid of systemic or local toxicity, and free of irritation
or foreign body response in tissues, and it does not result in hemolysis or mutation. The new bone readily grows into its
pores with direct contact to the implanted material. 11 cases of bone defects were treated with this artificial bone with
satisfactory results. 相似文献
63.
将150只SD大鼠随机地分成Ⅰ,Ⅱ,Ⅲ,Ⅳ四个实验组和一个对照组(Ⅴ)。实验组敌枯双剂量分别为1.0,0.2,0.05及0.01mg/kg,均用去离子水配成相应浓度的染毒水,由动物自由摄取,对照组摄入去离子水。于实验第29.5,55周分两批处死。经组织病理学检查,结果发现:敌枯双可引起甲状腺滤泡上皮细胞萎缩甚至脱屑,其发生率(Ⅲ组为63.64%)与对照组(0%)比较差异有高度显著性(P<0.01);睾丸曲细精管各级生精细胞减少、萎缩甚至完全消失,其发生率(Ⅳ组为58.33%)与对照组(8.33%)比较差异有显著性(P<0.01);对心肌、肝组织也有不同程度的损伤. 相似文献
64.
65.
五型病毒性肝炎的暴露因素与临床表现的比较 总被引:2,自引:1,他引:1
比较急性病毒性肝炎患者感染打危险因素,同时比较五型肝炎的症状和体征。连续收集急性病毒性肝炎患者血清293份,用ELISA法检测了五型肝炎病毒的病原学指标,并进行了流赞美同学调查。暴露因素:丙肝的肠道外暴露外明显多于甲肝;甲肝和戊肝有较高的“甲肝”患者接触史;乙肝,丙肝和丁肝有高的“乙肝”接触史,与甲肝,戊肝相比差异显著。 相似文献
66.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
67.
利用紫外吸收光谱、PAGE 垂直板 SDS—PAGE 及快速染色盘状 PAGE 酯酶电泳技术,对人、豚鼠的三种不同皮片的匀浆上清液蛋白成份含量及酯酶同工酶进行了比较分析,旨在为临床上应用新生皮片储皮移植提供理论依据。结果表明,豚鼠皮及人皮皮片匀浆上清液中的蛋白含量、光谱分析、PAGE、SDS-PAGE 及酯酶同工酶电泳,均是新生皮组的变化显著低于其它两组,而-196℃处理组与成年新鲜皮片组存在着较小差别,因此上述免疫生化学指标的判定结果为:新生皮<(差于)-196℃处理成年皮<(差于)新鲜成年皮。 相似文献
68.
69.
以往以乳头为圆心的同心圆剥离法常形成假体的移位,使假体的体表轮廓与前方的自然乳房分离,产生“双重乳房”现象。在研究了女性不同体位下不同的乳房形态及总结了以前的经验后,提出了偏心圆剥离的概念。偏心圆手术设计方法:以乳头为圆心,按其内侧、下侧为直径3/5的比例,以外侧、上侧为直径2/5的比例,形成一偏心圆的剥离范围。偏心圆的直径因考虑到假体的不同形态、大小及底面直径,以经中心假体纵截面的周长的1/2再放大2cm,作为剥离范围的直径。自1991年10月以来已应用了176例,无一术后移位现象,也没有固较多地剥离胸大肌内、下侧止点纤维而影响上肢活动。自然乳房并不是静态的圆锥形或半球形,它具有伸缩的组织学特点,又有随体位变动而变化的特点。用偏心圆法剥离,可使置入的假体与前方的自然乳房融为一体,消除“双重乳房”现象,而成为“真实”的乳房。同时也应积极寻找一种与身体组织相容性好的,弹性、比重与女性乳腺较为一致的,假体容量相对恒定的生物性材料。这样隆乳术才可以更广泛地开展。 相似文献
70.
John N. K. Hsiang Keith Y. C. Goh Xian-Lun Zhu Wai S. Poon 《Child's nervous system》1996,12(10):611-614
Head injury in children causes special concern in most communities. From 1989 to 1994, 2,785 children younger than 16 years old were admitted to our neurosurgical service because of head injury. Fall from a height was the major cause of head injury leading to admission in infants and children in preschool age groups, whereas traffic-related or bicycle-related accidents were more likely to be the cause of head injury for those aged 11–15 years. In all age groups there was a male preponderance. The overall mortality was 0.6%. Traffic-ralated accidents caused more severe injury and accounted for 67% of all fatalities. For patients under 6 years old, about 40% of head injuries occurred at home. Preventive measures for pediatric head injury in Hong Kong are suggested. 相似文献