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91.
肢端黏液样炎性纤维母细胞肉瘤2例及文献复习   总被引:1,自引:2,他引:1  
目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记,并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块,术后局部复发。镜检:病变呈多结节状,边界不清;黏液样基质中见数量不等的各类炎细胞浸润,散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型:肿瘤细胞Vim弥漫阳性,CD68和CD34灶性阳性,CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长,术后易局部复发,是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出,而特征性的瘤细胞稀疏,应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。  相似文献   
92.
慢性肾小球肾炎病人白细胞糖皮质激素受体的变化   总被引:1,自引:0,他引:1  
以氚标记的地塞米松(~3H-Dex)为配体,用一点分析法测定了23例慢性肾小球肾炎病人混合白细胞的糖皮质激素受体(GCR),平均为8825±2429位点/细胞((?)±SD)。与正常人5154±1635位点/细胞相比相差十分显著,P<0.01。其中16例并发尿毒症患者的GCR平均为9464±2571位点/细胞((?)±SD)。对这种变化的可能机制和临床意义进行了讨论。  相似文献   
93.
目的 :研究急性肾衰时肾微血管的损伤及樟柳碱、东莨菪碱、山菪莨碱对这些损伤的影响。方法 :采用左肾动脉注射油酸的方法建立大鼠急性肾衰模型 ,采用电镜、光镜及TTC显色观察大鼠急性肾衰不同时期肾微血管超微结构、肾组织结构及TTC显色的改变。结果 :左肾动脉注射油酸后 1 0min ,肾小球毛细血管内皮细胞坏死 ;肾小球毛细血管不同程度充血肿胀 ,在皮质与髓质交界区 ,可见小血管内充满大量红细胞 ;TTC显色呈鲜红色。注射油酸后 6h和 2 4h上述损伤加重 ,TTC显然出现典型的不显色苍白区。三种莨菪药物不同程度减轻了急性肾衰时肾微血管损伤 ,改善了肾组织缺血 ,减少了肾小管上皮细胞坏死数。结论 :急性肾衰时很早即出现肾微血管的损伤 ,三种莨菪药对急性肾衰时肾微血管和组织结构的损伤均有保护作用。  相似文献   
94.
目的:通过测定开胸患者术前及术毕血清皮质醇(Cortisol)和血浆血管紧张素Ⅱ(AT-Ⅱ)的水平,探讨应激前后开胸患者体内血清Cortisol和血浆AT-Ⅱ的变化。方法:无严重高血压、心脏病、垂体瘤及其它相关影响体内Cortisol、AT-Ⅱ水平疾病且具有手术指征的开胸患者35例(男18,女17),平均年龄(58.1±10.6)岁,分别在术前及术毕时采血,应用放射免疫分析测定血清Cortisol和血浆AT-Ⅱ的水平。结果:经配对t检验,结果显示开胸患者术毕血清Cortisol和血浆AT-Ⅱ与术前相比明显增高,存在显著性差异(t=-3.686~-3.575,P≤0.01);收缩压及心率,存在显著性差异(t=-2.35~4.72,P=0~0.025<0.05)。控制性别与年龄后,经部分相关分析,术毕心率与AT-Ⅱ呈显著正相关(r=0.41,P=0.035<0.05);与术毕Cortisol呈正相关(r=0.42,P=0.019<0.05)。结论:开胸患者术毕血清Cortisol、血浆AT-Ⅱ和心率明显增高。术后应密切监测开胸患者血清Cortisol及AT-Ⅱ的水平,作好相应的护理,以减少其它并发症的发生几率。  相似文献   
95.
Prolonged anoxia can cause permanent damage to synaptic transmission in the mammalian CNS. We tested the hypothesis that lack of glucose is the major cause of irreversible anoxic transmission damage, and that anoxic synaptic transmission damage could be prevented by glycolysis in rat hippocampal slices. The evoked population spike (PS) was extracellularly recorded in the CA1 pyramidal cell layer after stimulation of the Schaffer collaterals. When the slice was superfused with artificial cerebrospinal fluid (ACSF) containing 4 mM glucose, following 10 min anoxia, the evoked PS did not recover at all after 60 min reoxygenation. When superfusion ACSF contained 10 mM glucose with or without 0.5 mM alpha-cyano-4-hydroxycinnate (4-CIN), after 60 min reoxygenation the evoked PS completely recovered following 10 min anoxia. When superfusion ACSF contained 20 mM glucose with or without 1 mM sodium cyanide (NaCN), after 60 min reoxygenation the evoked PS completely recovered even following 120 min anoxia. In contrast, when superfusion ACSF contained 4 mM glucose, following 10 min 1 mM NaCN chemical anoxia alone, without anoxic anoxia, the evoked PS displayed no recovery after 60 min reoxygenation. Moreover, when 16 mM mannitol and 16 sodium L-lactate were added into 4 mM glucose ACSF, following 10 min anoxia the evoked PS failed to recover at all after 60 min reoxygenation. The results indicate that elevated glucose concentration powerfully protected the synaptic transmission against anoxic damage, and the powerful protection is due to anaerobic metabolism of glucose and not a result of the higher osmolality in higher glucose ACSF. We conclude that lack of glucose is the major cause of anoxia-induced synaptic transmission damage, and that if sufficient glucose is supplied, glycolysis could prevent this damage in vitro.  相似文献   
96.
Graded porous titanium coatings have been deposited on titanium substrates for dental implants by plasma spraying in an argon atmosphere. X-ray diffraction (XRD), scanning electron microscopy (SEM), surface roughness measurement, and tensile strength tests were performed on graded porous coatings. The results showed that Ti(3)O(5) was formed in the outermost surface of the porous coatings due to oxidation. The graded porous coatings consisted of three layers. The outer layer was full of macropores with a surface roughness of approximately 100 microm. The diameter of many macropores reached and even surpassed 150 microm, which could be beneficial for tissue to grow into the coating. The middle layer consisted of a mixture of micropores and macropores. The inner layer was a very dense and tight interface layer that included mechanical, physical, and metallurgical bonding. In tensile strength tests, testing bars peeled off the coatings, because the adhesive agent fractured, but the coatings remained intact.  相似文献   
97.
OBJECTIVE: To explore the genetic polymorphisms of four microsatellite DNA markers from telomeric HLA I region (D6S1624, D6S258, M6S211 and D6S510) and their linkage disequilibrium with HLA-A in a southern Chinese Han population residing in Hunan province. METHODS: Fluorescent PCR/Size-sequencing was carried out to analyze the polymorphisms of D6S1624, D6S258, M6S211 and D6S510 loci, and polymerase chain reaction-sequence specific priming (PCR-SSP) technique was used for HLA-A typing. RESULTS: The genotypic distributions at the 5 loci were consistent with Hardy-Weinberg equilibrium (P> 0.05). The number of allelic variants for D6S1624, D6S258, M6S211 and D6S510 loci were 10, 10, 12 and 9, respectively. Each locus had several main alleles and the dominant alleles were D6S1624-*199, D6S258-*195, M6S211-*261 and D6S510-*186. All of the 4 microsatellite markers exhibited high heterozygosity values (0.7142-0.8316) and polymorphism information content values (0.6686-0.811). No global linkage disequilibrium (LD) was detected between D6S1624 and HLA-A (P= 0.2646), or between D6S258 and HLA-A (P= 0.3481). In contrast, very significant global LD was found between M6S211 and HLA-A (P< 0.0001), and between D6S510 and HLA-A(P< 0.0001). Subsequent analysis for haplotypes with an observed frequency of > or = 3% revealed that only 2 of the 10 D6S1624-HLA-A haplotypes and 3 of the 9 D6S258-HLA-A haplotypes displayed weak or moderate LD, while 7 out of the 8 M6S211-HLA-A haplotypes, 6 among the 7 D6S510-HLA-A haplotypes were in tight LD. CONCLUSION: Authors have characterized four microsatellite DNA markers, D6S1624, D6S258, M6S211 and D6S510 in a southern Chinese Han population. Findings shown here can be helpful for those studies mainly addressing the association between HLA I sub-region and diseases. The data also provide basis for future study in forensics, HLA matching in clinical transplantation and anthropology.  相似文献   
98.
The intent of the present study was to use chemical or electrical stimulation of cerebellar afferents to determine how different stimulation paradigms affect the pattern of activation of different populations of neurons in the cerebellar cortex. Specifically, we analyzed immediate changes in neuronal activity, identified neurons affected by different stimulation paradigms, and determined the time course over which neuronal activity is altered. In the present study, we used either systemic (harmaline) or electrical stimulation of the inferior cerebellar peduncle (10 and 40 Hz) to alter the firing rate of climbing and mossy fiber afferents to the rat cerebellum and an antibody made against the proto-oncogene, c-fos, as a marker to identify activated neurons and glia. In control animals, only a few scattered granule cells express nuclear Fos-like immunoreactivity. Although no other cells show Fos-like immunoreactivity in their nuclei, Purkinje cells express Fos-like immunoreactivity within their somatic and dendritic cytoplasm in control animals. Within 15 min of chemical or electrical stimulation, numerous granule and glial cells express Fos-like immunoreactivity in their nuclei. Cells in the molecular layer express Fos-like immunoreactivity following harmaline stimulation in a time and lobule specific manner; they do not appear to be activated in the electrical stimulation paradigm. Following harmaline injections, there is an initial loss of Fos-like immunoreactivity in the cytoplasm of Purkinje cells; 90 min later, nuclear staining is observed in a few scattered Purkinje cells. Following electrical stimulation, the cytoplasmic staining in Purkinje cells is enhanced; it is never present in the nucleus. Data derived from this study reveal cell-specific temporal and spatial patterns of c-Fos activation that is unique to each paradigm. Further, it reveals the presence of an activity dependent protein in the cytoplasm of Purkinje cell somata and dendrites.  相似文献   
99.
大鼠脑动脉环的解剖学观察   总被引:5,自引:1,他引:5  
利用45只经墨汁乳胶混合液灌注的标本,观察大鼠的脑动脉环。观测发现:闭锁型动脉环的出现为97.78%,其前部多数由两侧胡脑前动脉及其合并而成的总前大脑动脉构成,后部多数由后交通动脉和基底动脉未端构成,动脉环的血管左,右对称,粗细相等者为80%,此种动脉环有利于制作脑缺血模型。  相似文献   
100.
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