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61.
目的制备岩沙海葵毒素(PTX)的人工抗原和抗血清,为建立PTX的酶联免疫检测方法提供技术基础。方法用小分子succinimidyl3-(2-pyridyldithio)propionate(SPDP)将PTX巯基化成半抗原PTX-PDP,用2-iminothiolane将大分子载体蛋白质匙眼血蓝蛋白(KLH)巯基化成KLH-SH,再将PTX-PDP和KLH-SH反应合成人工抗原PTX-PDP-KLH免疫雌性6~8周龄Balb/c小鼠,进行多抗的制备。用同样的方法制备酶联免疫反应之包被抗原PTX-PDP-BSA,用于检测血清抗体效价。结果根据紫外检测图谱,PTX的最大吸收波长在264nm处,KLH及BSA的最大吸收波长在278及279nm处,而合成的人工抗原PTX-PDP-KLH和PTX-PDP-BSA的最大吸收波长分别在267和273nm处。抗血清经间接酶联免疫吸附法检测,效价达到1∶3200,且与正常Balb/c小鼠、昆明种小鼠及兔血清间无交叉反应。结论合成的人工抗原纯度高,具有较好的免疫原性。 相似文献
62.
目的建立不同来源的千金藤植物中千金藤素的HPLC测定方法。方法采用Angela C18色谱柱(250 mm×4.6 mm,5μm);流动相:乙腈–水(52∶48,含0.5%三乙胺、0.01%磷酸);检测波长:282 nm;柱温:30℃;体积流量:1.0 m L/min;进样体积:20μL。结果千金藤素质量浓度在9~216μg/m L时与峰面积值呈良好的线性关系(r=0.999 7),平均回收率为96.0%,RSD值为2.0%(n=6)。产自湖南的千金藤(No.13)、产自广西的白药子(No.17)中千金藤素的量较高,分别为0.013 9%、0.122 1%;同一植株的不同用药部位(No.12~15)中千金藤素的量也不尽相同,湖南产千金藤中千金藤素主要分布在茎中,其质量分数为0.013 9%。结论该方法操作简便、准确、重复性好,可用于千金藤植物千金藤、地不容和白药子中千金藤素的测定。 相似文献
63.
64.
Infertility is defined as failure to achieve pregnancy within 12 months of unprotected intercourse in women. Trace elements, a kind of micronutrient that is very important to female reproductive function, are affected by intestinal absorption, which is regulated by gut microbiota. Enterotype is the classification of an intestinal microbiome based on its characteristics. Whether or not Prevotella-enterotype and Bacteroides-enterotype are associated with blood trace elements among infertile women remains unclear. The study aimed to explore the relationship between five main whole blood trace elements and these two enterotypes in women with infertility. This retrospective cross-sectional study recruited 651 Chinese women. Whole blood copper, zinc, calcium, magnesium, and iron levels were measured. Quantitative real-time PCR was performed on all fecal samples. Patients were categorized according to whole blood trace elements (low levels group, <5th percentile; normal levels group, 5th‒95th percentile; high levels group, >95th percentile). There were no significant differences in trace elements between the two enterotypes within the control population, while in infertile participants, copper (P = 0.033), zinc (P < 0.001), magnesium (P < 0.001), and iron (P < 0.001) in Prevotella-enterotype was significantly lower than in Bacteroides-enterotype. The Chi-square test showed that only the iron group had a significant difference in the two enterotypes (P = 0.001). Among infertile patients, Prevotella-enterotype (Log(P/B) > −0.27) predicted the low levels of whole blood iron in the obesity population (AUC = 0.894; P = 0.042). For the high levels of iron, Bacteroides-enterotype (Log(P/B) <−2.76) had a predictive power in the lean/normal group (AUC = 0.648; P = 0.041) and Log(P/B) <−3.99 in the overweight group (AUC = 0.863; P = 0.013). We can infer that these two enterotypes may have an effect on the iron metabolism in patients with infertility, highlighting the importance of further research into the interaction between enterotypes and trace elements in reproductive function. 相似文献
65.
胃肠道疾病可分为三类:器质性疾病、动力型疾病及功能性疾病.器质性疾病的诊断依赖于病理学,如胃肠道肿瘤.动力型疾病的诊断依赖于动力改变,如假性肠梗阻.功能性胃肠道疾病(functional gastrointestinal disorders,FGIDs)是一类主要通过症状进行诊断的疾病,而这些症状可与动力紊乱、内脏高敏感性、黏膜和免疫功能失调、肠道菌群失衡及中枢神经系统调节功能异常等相关,如功能性便秘、肠易激综合征等[1]. 相似文献
66.
子宫动脉栓塞术和米非司酮治疗子宫肌瘤比较研究 总被引:1,自引:0,他引:1
目的 观察子宫动脉栓塞术(UAE)和米非司酮(mifepristone)治疗子宫肌瘤的临床疗效、副作用及复发率.方法 子宫肌瘤患者共80例,随机分为2组,UAE组34例,行超选择性子宫动脉栓塞术.米非司酮组46例,口服米非司酮3个月.观察2组治疗前后子宫肌瘤大小、子宫体积变化、不良反应及复发率.结果 2种治疗方法均能明显改善临床症状,缩小子宫体积和肌瘤体积(P<0.01),且短期内米非司酮组比UAE组缩小明显(P<0.05).UAE后子宫肌瘤无复发,米非司酮治疗后有复发.UAE前后血清性激素变化差异无统计学意义(P>0.05),而米非司酮治疗前后变化差异有统计学意义(P<0.05),但可恢复.结论 UAE和米非司酮均为保守性治疗子宫肌瘤的有效方法,使临床症状减轻或消失.但米非司酮停药后有复发,适用于术前辅助用药和围绝经期治疗. 相似文献
67.
目的 总结胃食管反流病(GERD)的常用方剂及药对规律.方法 检索1994-2014年中医药治疗GERD的相关文献,提取辨证分型、用药等信息,建立Microsoft Excel 2003数据库,采用Crosstabs方法分析各证型、方剂、药对出现频次.结果 共纳入文献350篇,常见6种基本证型,依次为肝胃不和证、脾虚湿热证、肝胃郁热证、痰气交阻证、中虚气逆证、脾胃虚寒证;共使用方剂109个,中药143种.GERD肝胃不和证治疗以柴胡疏肝散为主;脾虚湿热证以半夏泻心汤居多;肝胃郁热证常用左金丸;痰气交阻证以半夏厚朴汤为主;中虚气逆证以旋覆代赭汤为主;脾胃虚寒证黄芪建中汤多见.文献中高频使用的药对组合是半夏-黄连、黄芩-黄连、芍药-甘草、柴胡-白芍等共19对.结论 中医药治疗GERD重视辨证论治的思想,多在主方、主药的基础上,综合考虑本证型病机特点,适当配伍其他类药物,或使其兼顾病机更加广泛,提高主药治疗效果,或防止主药作用太过,佐制其潜在副作用. 相似文献
68.
Jiao Peng Julia Y. Tsang Derek H. Ho Ruizhong Zhang Haitao Xiao Daxu Li Jiang Zhu Fenghua Wang Zhaoxiang Bian Vincent C. Lui Aimin Xu Paul K. Tam Jonathan R. Lamb Huimin Xia Yan Chen 《International journal of cancer. Journal international du cancer》2015,137(4):848-858
The plasticity of macrophages with selective functional phenotypes partially arises in respective to their microenvironment. Tumor‐associated macrophages (TAMs) may promote disease progression with tumor specific manner. Here we report that in pediatric malignant soft‐tissue tumors, the presence of TAMs and expression of adiponectin (APN) are heterogeneous. Both APN and TAMs had high expression in rhabdomyosarcoma, especially in the malignant subtype, alveolar rhabdomyosarcoma. To investigate the mode of action of APN on TAM activation, a murine MN/MCA1 sarcoma model was used. The Results revealed that exogenous APN had no effect on MN/MCA1 proliferation but tumor size was markedly reduced in apn?/? mice versus WT controls. The accumulation of TAMs in apn?/? mice was also reduced which correlated to downregulated serum levels of MCP‐1. Likewise, TAMs in apn?/? mice exhibited a M1‐like phenotype, characterized by increase in MHC IIhigh population and M1 phenotypic markers, such as iNOS gene and serum TNF‐α accompanied by a decrease in M2 markers, namely YM1 gene and serum IL‐10. In addition, APN deficiency increased the number of CD4+ T cells, CD8+ T cells and NK cells in tumors and reduced tumor metastasis. The altered phenotype of TAMs in apn?/? mice was associated with a marked decrease in phospho‐p38 and treatment with a p38 MAPK inhibitor significantly reduced tumor size and increased MHC II expression on TAMs in WT mice, implying p38 MAPK signaling pathway may contribute to APN‐mediated TAM polarization. Collectively, our findings suggest that APN may have a potential role in regulating soft tissue sarcoma growth. 相似文献
69.
Cancer stem cells (CSCs) are a relatively rare subpopulation of tumor cell with self-renewal and tumorigenesis capabilities. CSCs are associated with cancer recurrence, progression, and chemoradiotherapy resistance. Establishing a reliable platform for CSC enrichment and study is a prerequisite for understanding the characteristics of CSCs and discovering CSC-related therapeutic strategies. Certain strategies for CSC enrichment have been used in laboratory, particularly fluorescence-activated cell sorting (FACS) and mammosphere culture. However, these methods fail to recapitulate the in vivo chemical and physical conditions in tumors, thus potentially decreasing the malignancy of CSCs in culture and yielding unreliable research results. Accumulating research suggests the promise of a biomaterial-based three-dimensional (3D) strategy for CSC enrichment and study. This strategy has an advantage over conventional methods in simulating the tumor microenvironment, thus providing a more effective and predictive model for CSC laboratory research. In this review, we first briefly discuss the conventional methods for CSC enrichment and study. We then summarize the latest advances and challenges in biomaterial-based 3D CSC platforms. Design strategies for materials, morphology, and chemical and physical cues are highlighted to provide direction for the future construction of platforms for CSC enrichment and study. 相似文献
70.
Molecular characteristics of rifampin and isoniazid resistant Mycobacterium tuberculosis strains from Beijing, China 总被引:2,自引:0,他引:2
Background China is one of the high burden countries of Mycobacterium tuberculosis (TB) infection globally, with high incidence and mortality. We studied the molecular characteristics of rifampin (RIF) and isoniazid (INH) resistant Mycobacterium tuberculosis strains from Beijing, China, in order to find out the genetic marker for rapid detection of specific drug resistance.
Methods Forty pansusceptible and 81 resistant strains of Mycobacterium tuberculosis isolated from Beijing, China during 2002-2005 were analyzed. The modified rifampin oligonucleotide (RIFO) assay based on reverse line blot hybridization was used to detect mutations in the 81 bp hot-spot region of rpoB gene, which is associated with RIF resistance. The INH resistance associated genes, regulatory region mab-inhA (-15C/T) and structural gene katG S315T were detected by reverse line blot hybridization and PCR-restriction fragment length polymorphism (RFLP) method respectively. All the strains were typed by spoligotying and the Beijing genotype was further subdivided by NTF locus analysis. The distribution of drug resistance associated mutations in the above genes was compared in these groups.
Results Sixty-five (91.5%) of 71 RIF resistant and 52 (92.9%) of 56 multidrug-resistant (MDR, i.e. resistant to at least RIF and INH) strains were found to harbor mutations in the rpoB hot-spot region. No mutation was detected in RIF sensitive strains. The specificity and sensitivity of the modified RIFO assay were 100% and 91.5%, respectively, katG315 AGC〉ACC and inhA-15C〉T mutations were found in 40 (60.6%) and 10 (15.2%) of 66 INH resistant strains, respectively; 7.6% of INH-resistant strains had mutations in both of these genes. Therefore, a combined use of both katG315 and inhA-15 identified 68.2% of INH-resistant strains. The Beijing genotype accounted for 91.7% of total strains and was further subdivided into "modern" (76.6%) and "ancestral" (23.4%) group. There is no significant difference between "ancestral" and "modern" group in prevalance of drug resistance-associated gene mutations.
Conclusions The hot-spot region of rpoB gene can be used as genetic marker for detection of RIF resistant strains; a combined use of both katG315 and inhA-15 can improve the detection rate of I NH resistant strains; the Beijing genotype is prevalent in Beijing, China; the modified RIFO assay can be a practical tool for rapid detection of RIF resistant and MDR isolates in the routine diagnostic work. 相似文献