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41.
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
42.
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
43.
44.
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
45.
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
46.
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
47.
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
48.
为探讨前列腺癌(PCa)细胞的转移机制,应用免疫组织化学ABC法在良性前列腺增生(BPH)及PCa组织中对基膜连接蛋白(LN),胶原Ⅳ型蛋白(COLⅣ),纤维连接蛋白(FN)等细胞外基质(ECM)蛋白的表达进行检测,结果BPH组织中基底膜部位LN,COLⅣ及FN的染色呈连续线状分布,PCa组组织基底膜部位LN,COLⅣ及FN的阳性染色呈碎片状或断线状分布。COLⅣ在BPH与PCa组织中的强阳性率无显著性差异(P>0.05)。结果提示ECM在PCa组织中基底膜部位的明显缺失(非连续线状分布)可能是肿瘤转移的重要因素。 相似文献
49.
报道7例自发性食管穿孔治疗经验,并对诊断和治疗和治疗新方法进行了讨论,自发性食管穿孔早期诊断的重要依据是迅速获得完整,详细的发病史。可疑时通过食道造影,胸腔穿刺刺液的分析而确诊。一经确诊应急取早期食管修补,对发病时间长,全身情况差的病人,经积极准备后仍应急取食管修补,对不宜手术者给予食管冲洗促进穿孔愈合。同时给予有效的食管腔内外引流。 相似文献
50.
报告1994年我院临床标本检出的常见菌及其对抗生素的敏感性变化。结果表明,革兰氏阴性杆菌占检出菌的第一位63.72%,革 兰氏阳性菌居第二位29.41%。在革兰氏阴性杆菌中铜绿假单胞菌居首位,并占革兰氏阴性杆菌的29.23%;大肠艾希氏菌占第二位22.77%,不动杆菌占第三位12.30%。在革兰氏阳性球菌中,凝固酶阴性葡萄球菌居检出菌的第一位,并占革兰氏阳性球菌的37.33%;金黄色葡萄球菌占第二 相似文献