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101.
J J Malcorra-Azpiazu M I Balda-Aguirre J C Diaz-Chico H Hu J B Wilson B B Webber F Kutlar A Kutlar T H Huisman 《Hemoglobin》1988,12(2):163-170
A new hemoglobin variant with a Ser----Phe substitution at position beta 49(CD8) was discovered in two members of a family living in the Canary Islands, Spain. Detection was by polyacrylamide gel electrophoresis and by reversed phase high performance liquid chromatography. The variant, which constituted 43% and 45%, respectively, in the two heterozygotes, was slightly unstable. Its presence did not affect hematological values though there was a mild reticulocytosis. 相似文献
102.
哒嗪酮酸类化合物的合成及其抗惊活性的研究 总被引:1,自引:0,他引:1
以a-酮戊二酸与水合肼与水合肼为原始原料合成了15个N-(3’-磷酸二乙酯丙基)-1,6-二氢-6-氧-3-哒嗪酰胺类化合物,并对它们进行了最大电休克发作(MES)实验,结果表明其中4个化合物表现出中等强度的抗惊活性。 相似文献
103.
对17例胸部冠状面CT增强扫描的应用价值作了介绍,其中16例获得良好结果,与常规体层摄影相似,能使气管、主支气管完整地显示。轴扫只显示气管的某一层面,故对中心型肺癌的定位准确性不如冠扫。增强冠扫后可使纵隔肺门的血管结构清晰地显影,因此能区分脂肪过多症,囊性或血管性病变而明确诊断。 相似文献
104.
近些年来对A群多糖脑膜炎菌苗最适免疫剂量进行了一系列现场流行病学及血清学效果的对比研究。首先肯定了我国生产的菌苗与法国Merieux研究所生产的苗苗在人体接种后观察一年内具有同等杀菌抗体反应。以后在严格对比下观察了国内生产的多糖菌苗接种30μg及50μg一年内的血清杀菌抗体反应。结果完全相同;而全身反应则30μg为50μg剂量的五分之一。在我国80年代流脑流行地区内确证了30μg免后人群保护率为99%与国外50μg的保护率(97.2%)相似。国内连续三年在流行地区内对比观察了30μg、与50μg的流行病学预防效果,其人群保护率相似.与国外(Reingold).的报告亦相似。最后结论是本菌苗的最适免疫剂量为30μg.不但其预防效果与50μg相同,而且菌苗反应轻微,经济效益高,有利于在发展中国家推广使用。 相似文献
105.
促甲状腺素释放激素拮抗β-内啡肽对心血管的抑制作用 总被引:2,自引:0,他引:2
本研究用兔侧脑室给药观察了促甲状腺素释放激素(TRH)对β-内啡肽心血管抑制作用的影响。结果表示,β-内啡肽(10μg,icv)能显著抑制兔心血管功能,表现为血压下降,心机收缩力指标如左室收缩压(LVSP),心室内压最大上升和下降速率(±dp/dtmax),心肌纤维收缩速度(Vce40,Vpm)和心肌收缩向量环面积(Lp)明显降低。β-内啡肽的这一作用可被TRH(50μg,icv)取消,阿片受体拮抗剂纳洛酮(NAL,50μg,icv)也可拮抗β-内啡肽的心血管抑制作用,表明,TRH与内源性阿片肽系统有密切关系,结合以前的实验结果提示TRH拮抗β-内啡肽的心血管抑制作用有可能是作用在阿片受体上的。 相似文献
106.
胃癌单克隆抗体-丝裂霉素C结合物的制备及其细胞毒特征 总被引:1,自引:1,他引:0
作者报道胃癌单克隆抗体MG11-丝裂霉素C(MMC)结合物的制备及其对肿瘤细胞的杀伤作用。首先用戊二酐处理MMC,于MMC上引入羧基,MMC衍生物与N羟基琥珀酰亚胺及2,2′-二环已基碳二亚胺反应,得到MMC活性酯,后者与抗体反应将MMC引入抗体中。经测定,每克分子抗体中引入约6~7克分子药物,结合物对人胃癌细胞KATⅢ具有较强的选择性杀伤作用,在0.56μg/ml水平(药物浓度)对肿瘤细胞杀伤牢达60%,优于游离药物(51%)及无关抗体结合物(9.3%),提示选用的胃癌单抗对MMC具有较好的导向作用。 相似文献
107.
108.
观察了雷公藤多甙(T_Ⅱ)对柔红霉素肾病大鼠肾皮质丙二醛(MDA)、血清MDA、尿蛋白和肾脏病理组织学的影响:T_Ⅱ显著降低柔红霉素肾病大鼠尿蛋白、肾皮质MDA和血清MDA,肾脏病理组织学改变也明显减轻,这些变化类似于自由基清除剂(超氧化物歧化酶、过氧化氢酶和维生素E)对该模型的影响。结果提示T_Ⅱ具有清除氧自由基和(或)阻断脂质过氧化反应作用,可能是T_Ⅱ抗炎机制所在。 相似文献
109.
Inheritance of Graves' disease has been linked to the HA-DR3 gene product which may function in some specific way in antigen presentation. To determine whether the first extracellular domain of this protein, which is specifically involved in antigen presentation, has the same sequence in patients with Graves' disease and in normal individuals, we have amplified the second exon using the polymerase chain reaction, and then cloned and sequenced the DNA segment. In eight subjects with Graves' disease, sequences identical to prototypic reported sequence for DRB1*0301 were recovered, and in two individuals sequences varied by a few nucleotides, leading to 1-3 amino acid substitutions which did not occur in a pattern. Sequences identical to the prototypic sequence known as DRB3*0101, also previously known as DRw52, were also recovered. Thus the HLA-DRB1 and B3 genes present in patients with autoimmune disease appear to be the same as those present in the general population. These observations indicate that a unique allele is not present in patients with autoimmune disease, but rather that the normal DR3 allele itself, in a manner yet to be described, increases the probability of developing autoimmune thyroid disease. 相似文献
110.
Altered expression of retinoblastoma protein and known prognostic variables in locally advanced bladder cancer. 总被引:11,自引:0,他引:11
C J Logothetis H J Xu J Y Ro S X Hu A Sahin N Ordonez W F Benedict 《Journal of the National Cancer Institute》1992,84(16):1256-1261
BACKGROUND: The clinical behavior of the tumor in patients with locally advanced bladder carcinoma is unpredictable. Current predictors of clinical behavior include depth of muscle invasion, presence of vascular invasion, proliferation rate, and loss of blood group antigens. Treatment selection would be facilitated by the development of a reliable marker of tumor progression. Functional retinoblastoma (RB) gene loss has been reported to occur in bladder carcinoma, but the significance of this loss is unknown. PURPOSE: We have evaluated the frequency of functional loss of the RB gene in locally advanced bladder carcinoma and have compared the results to known prognostic factors in the same cohort. METHODS: Forty-three study patients with pathologically well-characterized, locally advanced bladder carcinoma, who were placed in a protocol incorporating surgery and chemotherapy, were studied for known clinical and pathological prognostic indicators as well as for their Rb status. Formalin-fixed and paraffin-embedded archival primary tumor tissues were used for histological and immunohistochemical analyses. RESULTS: Altered Rb protein expression was documented in 37% of the tumor specimens. The high rate of altered Rb expression found in this cohort with advanced urothelial tumors strongly suggests that RB functional loss may be associated with tumor progression in this malignancy. Altered Rb protein expression was found to be independent of other known prognostic variables. A significantly poorer tumor-free survival rate also was noted for those patients who had a tumor with an altered Rb protein with or without vascular invasion. CONCLUSION: The high frequency of Rb alteration in locally advanced bladder carcinomas, plus the fact that a significant correlation could not be found between the Rb status and other known prognostic markers in this preliminary study, suggests that altered RB expression may be an independent prognostic marker of tumor progression in bladder cancer. 相似文献