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61.
采用斑点免疫金银染色(Dot-IGSS)试验对4种日本血吸虫抗原的敏感性及特异性进行比较。结果显示粗提成虫抗原(AWA)、尿素溶解性成虫抗原(JWU)、硫酸铵沉淀成虫抗原(AW)和可溶性虫卵抗原(SEA)检测40例日本血吸虫病人血清抗体的敏感性均达100.0%,40例正常人血清的可疑阳性反应分别为2.5%、0、2.5%和0,40例肝吸虫病人血清的可疑交叉率分别为2.5%、0、2.5%和0,表明在高敏感的IGSS检测系统中,粗提成虫抗原的敏感性和特异性与部分纯化者和虫卵抗原无显著性差异(P>0.05)。  相似文献   
62.
补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响   总被引:4,自引:0,他引:4  
观察补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响。用SD雌性大鼠幼仔,出生9d龄注射丙酸睾丸酮,制成雄激素致不孕大鼠(ASR)模型。80d龄灌服补肾中药水溶液两周。100d龄心脏灌注处死。以核仁组成区蛋白嗜银染色(AgNOR)和增殖细胞核杭原(PcNA)为指标,观察卵巢颗粒细胞、间质腺细胞的形态学变化。结果:补肾中药能够使ASR卵巢颗粒细胞增殖、卵泡发育。治疗组的AgNOR和PcNA计数明显高于模型组,而与对照组之间无显著差异。结论:补肾中药的这种作用可能是通过调节了下丘脑-垂体-卵巢性腺功能的结果,从而促使卵巢颗粒细胞发育、卵泡成熟。  相似文献   
63.
The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca2+-Mg2+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl2 (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n=6) or twice at 24 and 48 h before ischemia (subacute group; n=14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity.  相似文献   
64.
My experience with more than 80 cases of the late infantile and juvenile forms of the neuronal ceroid-lipofuscinoses over the last 5 years has led to the following realizations. The 2 variants are neurologically distinct entities and probably are the result of different genetic defects. Treatment includes supportive measures and anticonvulsant medication. Therapy for behavioral and psychiatric disturbances in the juvenile type proves to be particularly challenging as neuroleptic medications tend to worsen parkinsonian like symptoms. Neuropathologic and neuro radiologic explanation of clinical symptomatology correlates best with neuronal loss and not neuronal storage. There is a paucity of neuropathologic documentation of these 2 types; additional reports are encouraged.  相似文献   
65.
Background: Oncogenes and other molecular tumor markers that predict tumor aggressiveness may allow individualization and optimization of surgical therapy of intermediate-thickness malignant melanoma. We examined the expression of selected markers, including the HLA-DR antigen, the heat shock protein-70 (HSP-70), and the c-myc oncogene in primary melanoma and regional nodes and related these findings to metastatic potential and survival. Methods: Forty patients with primary melanoma (1.5–4.0 mm) were studied, all of whom had prophylactic lymph node dissection and were followed for 18 months to 7 years. The primary tissue and nodes were examined using immunohistochemical techniques for the presence of HLA-DR antigen and HSP-70 protein and the expression of the c-myc oncogene. Results: Of 40 patients, there were 23 with lesions 1 to 2.9 mm thick and 17 with lesions 3 to 4 mm thick. Nodal metastases were present in 25 of the 40 patients who had elective node dissection. HLA-DR antibody stained the primary tumor in 10 patients (25%), but there was no correlation with survival in this group. HLA-DR antibody stained the stroma and cellular infiltrates surrounding the primary tumor in 28 of 40 patients; in this group there was a correlation of HLA-DR staining of the peritumoral stroma with improved survival overall. HLA-DR staining of the peritumoral stroma also influenced survival when patients were stratified by tumor thickness groups 1 to 2.9 mm and 3 to 4 mm and presence of nodal metastases. HSP-70 was demonstrated in the primary tumor in 25% of patients, who were also shown to have significantly improved survival when compared with those whose primary tumor did not stain with HSP-70. C-myc was expressed in the primary tumor in 25%, but showed no correlation with survival. None of these proteins correlated with or predicted the presence of nodal metastases. Conclusion: We conclude that the use of specific molecular-oncogene markers in intermediate-thickness primary melanoma may identify patients at high risk for conventional treatment failure and reduced survival who may profit from more aggressive surgery, adjuvant therapy, or both.Presented at the 48th Annual Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995.  相似文献   
66.
应用放射免疫测定法,对20例胃肠癌患者进行了血清癌胚抗原(CEA)测定,并应用免疫组化法对其中16例癌组织中的CEA进行了检测.检测结果,血清CEA阳性6例,癌组织CEA阳性9例.低分化癌的血清CEA显著高于高分化癌(P<0.05).血清CEA与癌灶部位、癌组织CEA与分化程度及血清CEA均无关(P>0.05).提示血清CEA的含量与癌组织的分化程度有关,血清CEA与癌组织内的CEA无平行关系.作者并对其机制及检测CEA的意义进行讨论.  相似文献   
67.
不同时期的典型何杰金氏病18例,用抗PC_(10)、L_(26)、UCHL-1抗体作SP免疫组化染色。结果显示:无一例阴性病例。PC_(10)阳性的HRS细胞百分率与传统分类比较有相关性。L_(26)和UCHL_1阳性细胞的百分率分别为11.3%~21.5%和38.2%~49.5%。表明不存在单一的B或T细胞免疫表达。提示HRS细胞与背景中淋巴细胞之间其细胞来源有内在联系。  相似文献   
68.
Polygenesregulateapoptosis .bcl 2isananti apoptosisgene ,whilebaxisapro apoptosisgene .L Tetrahydropalmatine (L THP) ,akindofalkaloidextractedfromtraditionalChinesemedicineRhizomacorydalis,possessesanalgesic ,sedativeandhypnoticeffects.Recently ,ithasbeen…  相似文献   
69.
增殖细胞核抗原及nm23在胃癌中的表达及意义   总被引:2,自引:0,他引:2  
目的 :探讨增殖细胞核抗原 (PCNA)及nm2 3基因在胃癌中的表达及其与生物学行为的关系。方法 :应用免疫组化SP法研究 85例胃癌手术标本中PCNA及nm2 3基因的表达。结果 :在 85例胃癌中PCNA、nm2 3的总阳性表达率分别为 5 2 9% (4 4 / 85例 )和 4 4 .7% (38/ 85例 ) ,PCNA及nm2 3在胃癌中的表达与其淋巴结转移、浸润深度、分化程度有关 (P <0 0 5 ,P <0 0 1 ) ;PCNA与分化程度无关 ,P >0 0 5。结论 :PCNA及nm2 3参与了胃癌的发生、发展、浸润及转移  相似文献   
70.
小儿乙状结肠冗长症病理特点分析   总被引:11,自引:0,他引:11  
目的 探讨小儿乙状结肠冗长症的病理特点,以提高对该症病理特点的认识。方法 分析我科1993~2002年间经手术治疗12例小儿乙状结肠冗长症的临床病理资料。结果 小儿乙状结肠冗长症病理特点与先天性巨结肠同源病相似。主要表现为乙状结肠肠壁肥厚,部分肌纤维变性。结肠黏膜萎缩,黏膜下充血水肿;肌间神经丛减少,均可见神经节细胞发育幼稚,且数量减少或体积变小,呈固缩或空泡变性。结论 小儿乙状结肠冗长症大多有肠神经元发育异常。  相似文献   
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