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991.
Camptothecin (CPT) and its analogues show potent antitumour activity. However, poor water solubility and severe side effects have restricted their applications in clinical practice. In this paper, a novel self‐assembly based on camptothecin and carbamoylmannose conjugates ( CPT‐Man ) was constructed. The self‐assembly increased the water solubility of camptothecin to 0.64 mg/ml and antitumour activity. Moreover, CPT‐Man could induce obvious cancer cell apoptosis. This work provides a new approach for exploring carbohydrate‐modified antitumour properties by self‐assembled CPT drugs.  相似文献   
992.
目的 观察贝伐珠单抗联合伊立替康与雷替曲塞方案在氟尿嘧啶类药物耐药后的晚期结直肠癌患者中的疗效及安全性。方法 收集中国医科大学附属第一医院2014—2019年收治的氟尿嘧啶类耐药的60例晚期结直肠癌患者,对照组30例,应用伊立替康联合雷替曲塞方案(IR);实验组30例,应用IR联合贝伐珠单抗方案。分析比较两组患者的客观有效率(ORR)、疾病控制率(DCR)、无进展生存时间(PFS)及不良反应发生情况。结果 实验组和对照组ORR分别为6.67%和3.33%,DCR分别为66.67%和53.33%,两组ORR和DCR比较差异无统计学意义。实验组和对照组中位PFS分别为6.0个月和3.1个月,差异有统计学意义(P=0.020 4)。两组不良反应以Ⅰ/Ⅱ级多见,Ⅲ/Ⅳ级不良反应发生率低,实验组蛋白尿的发生率高于对照组,差异有统计学意义(P=0.001)。其余如出血、转氨酶升高、恶心、呕吐、腹泻、发热、皮疹、高血压等不良反应发生率均为实验组高于对照组,但差异无统计学意义。结论 贝伐珠单抗联合伊立替康与雷替曲塞方案可提高既往氟尿嘧啶类治疗耐药后的晚期结直肠癌患者的疗效,无进展生存期增加,不良反应可耐受,值得进一步研究。  相似文献   
993.
目的了解妊娠期哮喘患者哮喘控制及药物使用的情况,分析妊娠期哮喘控制不佳的原因。方法通过对41例诊断为哮喘的妊娠期女性进行问卷调查,收集其目前哮喘控制水平、药物使用情况、吸入装置与吸入技巧、用药依从性、对疾病和药物的认识、影响哮喘控制的因素等情况,根据答题结果分析。结果根据哮喘控制问卷评分,"良好控制"占39.0%;"部分控制"+"未控制"占61.0%。在妊娠期间,34.1%患者有过至少1次因哮喘急性发作门/急诊就诊或入院治疗。20.0%患者能正确吸入药物,52.6%患者用药依从性较好。39%患者认为吸入激素对胎儿危害会大于哮喘,61.0%患者分不清楚缓解药和控制药。影响哮喘控制原因中,48%患者担忧激素会对胎儿影响,无患者选择经济因素。结论妊娠期哮喘控制欠佳,药师参与妊娠哮喘患者管理有望提高其控制水平。  相似文献   
994.
BackgroundThromboelastography (TEG) provides global assessment of hemostatic function and has been recommended to monitor potential coagulopathies during pregnancy in which hypercoagulable state is favored. In present study, we established the reference intervals (RIs) of the TEG parameters (R, K, MA, and α‐angle) with Chinese pregnant women of third trimester. In addition, we examined the diagnostic efficacies of the TEG parameters in the patients diagnosed of gestational hypertension (GH), gestational diabetes mellitus (GDM), or preeclampsia (PE).MethodsWith specified including and excluding criteria, non‐pregnant controls, healthy pregnant women, and pregnant women with GH, GDM, or PE had their venous blood drawn at Beijing Obstetrics and Gynecology Hospital, followed by TEG tests performed in the clinical laboratory.ResultsThe RIs determined with the healthy pregnant women (in third trimester) for R, K, MA, and α‐angle were 4.0‐7.7, 1.2‐3.2, 51.9‐70.1, and 41.4‐74.4, respectively. When compared with the healthy pregnancy group, the K value was significantly decreased in GH patients but increased in PE patients; MA was significantly lower in the PE group. In the receiver operating characteristic curve (ROC) analyses, K value was able to efficiently distinguish normal pregnancy from the GH patients, with an AUC of 0.86 which is far better than those of R (AUC = 0.57) and MA (AUC = 0.56). For the PE patients, the AUC of MA (0.69) was significantly greater than that of R (0.50).ConclusionsThromboelastography may provide more accurate experimental basis for monitoring coagulation functions especially in pregnant women with complications of GH and PE.  相似文献   
995.
BackgroundMismatch repair deficiency (dMMR) status induced by MLH1 protein deficiency plays a pivotal role in therapeutic decision‐making for cancer patients. Appropriate quality control (QC) materials are necessary for monitoring the accuracy of MLH1 protein deficiency assays used in clinical laboratories.MethodsCRISPR/Cas9 technology was used to edit the MLH1 gene of GM12878Cas9 cells to establish MLH1 protein‐deficient cell lines. The positive cell lines were screened and validated by Sanger sequencing, Western blot (WB), and next‐generation sequencing (NGS) and were then used to prepare formalin‐fixed, paraffin‐embedded (FFPE) samples through xenografting. These FFPE samples were tested by hematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) for suitability as novel QC materials for MLH1 protein deficiency testing.ResultsWe successfully cultured 358 monoclonal cells, with a survival rate of 37.3% (358/960) of the sorted monoclonal cells. Through Sanger sequencing, cell lines with MLH1 gene mutation were identified. Subsequently, two cell lines with MLH1 protein deficiency were identified by WB and named as GM12878Cas9_6 and GM12878Cas9_10. The NGS results further confirmed that the MLH1 gene mutation in these two cell lines would cause the formation of stop codons and terminate the expression of the MLH1 protein. The H&E staining and IHC results also verified the deficiency of the MLH1 protein, and FFPE samples from xenografts proved their similarity and consistency with clinical samples.ConclusionsWe successfully established MLH1 protein‐deficient cell lines. Followed by xenografting, we developed novel FFPE QC materials with homogenous, sustainable, and typical histological structures advantages that are suitable for the standardization of clinical IHC methods.  相似文献   
996.
997.
998.
Keratin 1 is found in the upper layers of the epidermis, on the surface of endothelial cells and in the membrane of the neuroblastoma NMB7. It is important for the structural integrity of the skin, has been found to regulate the activity of kinases, such as protein kinase C (PKC) and SRC, to participate in complement activation by the lectin pathway and to be involved in fibrinolysis, angiogenesis and the response to oxidative stress. Studies of the polymorphisms of the Keratin 1 (KRT1) gene have been driven mostly by interest in its role in skin diseases. However, much of the KRT1 variation occurs in normal populations and is not associated with dermal pathology. In the present experiments, we have investigated the polymorphism of KRT1 genes by nucleotide sequencing in normal families and normal populations of European, African, Hispanic and Asian background. The frequencies of the KRT1 alleles were strikingly different in the four ethnic groups and most of the mutations resulted in amino acid substitutions, with only 3 out of 19 being synonymous. Analysis of selective neutrality by the Ewens–Watterson and Tajima D statistics showed that KRT1 allele homozygosity was decreased in three of the populations suggesting that KRT1 genes may be under the influence of balancing selection. It is possible that the role of KRT1 as a receptor, rather than its structural function in the epidermis, is what drives the selective forces that are apparent in the inheritance of this gene.  相似文献   
999.
1000.
Metallothioneins (MTs) are a group of metal binding proteins thought to play a role in the detoxification of heavy metals. Here we showed by microarray and validation analyses that MT1h, a member of MT, is down‐regulated in many human malignancies. Low expression of MT1h was associated with poor clinical outcomes in both prostate and liver cancer. We found that the promoter region of MT1h was hypermethylated in cancer and that demethylation of the MT1h promoter reversed the suppression of MT1h expression. Forced expression of MT1h induced cell growth arrest, suppressed colony formation, retarded migration, and reduced invasion. SCID mice with tumour xenografts with inducible MT1h expression had lower tumour volumes as well as fewer metastases and deaths than uninduced controls. MT1h was found to interact with euchromatin histone methyltransferase 1 (EHMT1) and enhanced its methyltransferase activity on histone 3. Knocking down of EHMT1 or a mutation in MT1h that abrogates its interaction with EHMT1 abrogated MT1h tumour suppressor activity. This demonstrates tumour suppressor activity in a heavy metal binding protein that is dependent on activation of histone methylation. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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