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91.
Luo L Zeng J Liang B Zhao Z Sun L Cao D Yang J Shen K 《Experimental and molecular pathology》2011,(2):596-602
Cancer stem cells (CSCs) play an important role in the recurrence and drug resistance of cancer. Isolation and characterization of CSCs from ovarian cancer samples may help to provide novel diagnostic and therapeutic targets in the management of recurrent disease and drug resistance in ovarian cancer. Here, we developed a xenograft model in which cells from 14 samples of human ovarian serous adenocarcinoma tissue or ascites were implanted in immunodeficient mice to test the tumorigenic potential of different populations of ovarian cancer cells. We identified and isolated the tumorigenic cells as CD117+Lineage− from three different xenografts. As few as 103 cells with the CD117+Lineage− phenotype, which comprise < 2% of the xenograft tumor cells, were able to regenerate tumors in a mouse model, a 100-fold increase in tumorigenic potential compared to CD117−Lineage− cells. The tumors that arose from purified CD117+Lineage− cells reproduced the original tumor heterogeneity and could be serially generated, demonstrating the ability to self-renew and to differentiate, two defining properties of stem cells. Furthermore, immunohistochemistry analysis of 25 patients with advanced ovarian serous adenocarcinoma revealed positive immunostaining for CD117 in 40% (10 of 25) of patients. CD117 expression was statistically correlated with resistance to conventional chemotherapy (P = 0.027). In conclusion, our study demonstrates that human ovarian cancer cells with the CD117+ phenotype possess the unique properties of CSCs, including self-renewal, differentiation, a high tumorigenic potential, and chemoresistance. Future studies designed to target CD117+ cancer cells may identify more attractive and effective therapies for treatment of ovarian cancer. 相似文献
92.
93.
Lou W Cao D Yang J Guo L Shen K 《International journal of clinical oncology / Japan Society of Clinical Oncology》2011,16(6):705-708
The management of the retiform variant of Sertoli–Leydig cell tumor remains a challenge for the gynecologist. Surgery is the
preferred treatment, but it is still inconclusive whether complete staging or postoperative adjuvant therapy is necessary.
A 9-year-old girl was admitted with a well-circumscribed, solid cystic mass in the lower abdomen, of size corresponding to
a 20-week gravid uterus, without any androgenic manifestations. Per-operatively, the mass arose from left ovary, which had
a smooth outer surface with intact capsule. A cut section was almost multiloculated with cysts ranging from 0.5 to 2.5 cm
in diameter and filled with thin yellow or brown serous fluid. Left salpingo-oophorectomy, bilateral lymph node dissection,
infracolic omentectomy and appendectomy were performed. The pathological diagnosis was retiform pattern of intermediate to
poorly differentiated Sertoli–Leydig cell tumor. The clinical stage was IA. The patient was followed up 3-monthly, and was
disease-free at 18-month follow-up after the initial treatment. After review of the literature, we conclude that the retiform
variant is a special subtype of Sertoli–Leydig cell tumors. Because of their young age, the uncertain malignant potential
and rare bilaterality, patients should be treated conservatively whenever possible. There is at present no good evidence that
postoperative adjuvant therapy is effective in preventing recurrence. 相似文献
94.
Xue Zhou Mei Ding Chunli Ding Jun Yao Hao Pang Jiaxin Xing Jinfeng Xuan Baojie Wang 《Journal of molecular neuroscience : MN》2013,49(3):625-631
The hypothesis for the etiology of schizophrenia involves various neurotransmitters, including 5-HT. Metabolic disorder of 5-HT is an important underlying neurobiochemical cause leading to the development of mental illness. Abnormality in the receptors involved in 5-HT synthesis and metabolism may affect the functioning of 5-HT in the central nervous system. There are seven types of 5-HT receptor families, with a total of 15 corresponding subtypes. HTR1A is the most abundantly expressed 5-HT receptor subtype in the mammalian brain. SNPs in HTR1A enhance or weaken the functioning of 5-HT by affecting HTR1A expression levels or ligand-binding activity, thereby placing HTR1A in an important role in the study of diseases of the nervous system. This study employed DNA sequencing to investigate HTR1A fragment lengths, including complete exons as well as 5′ FR and 3′ FR segments, for a total of 2,718 bp. Seven SNP loci (ss212928868, rs6295, rs6294, ss218178047, rs34118353, rs6449693, and rs878567) were found in 182 healthy volunteers and 161 patients. Among them, two SNP loci had not been reported in the National Center for Biotechnology Information (NCBI) database, promoter locus ss212928868 and exon locus ss218178047, which now have been approved by the NCBI database and assigned rs numbers, rs113195492 and rs112846276, respectively. ss212928868 and rs6294 were statistically different between control and paranoid schizophrenic women (P?<?0.05), and both loci were in a state of linkage disequilibrium. However, statistical significance was lost after Bonferroni correction. Compared with the GG genotype, the GA + AA genotype had a decreased disease risk (odds ratioGA + AA?=?0.3529, 95 % confidence interval?=?0.1319–0.9444). The data showed that changes in SNP loci of HTR1A were different between paranoid schizophrenic and control group women. Although such differences were lost after statistical correction, studies with larger sample sizes have not been conducted. Combined with the newly discovered loci, these findings can point out possible directions for future investigations in different populations. 相似文献
95.
Bei Zhang Zhe Wang Fucong Peng Jiaxin Fang Liqun Guo Chunli Lu Tianying Wu Hongxia Liu 《中医科学杂志(英文)》2022,9(1):22-33
ObjectiveRecently, the effects of Baduanjin (a traditional Chinese mind-body exercise) on diabetes have attracted increasing attention, and relevant systematic reviews (SRs) have emerged. However, the qualities of these SRs vary markedly, and their conclusions are inconsistent, which is not conducive to guiding decision-making. We sought to assess the quality of these SRs and provide more evidence for diabetes treatment.MethodsA literature search was conducted in 7 databases from inception to December 1st, 2021. SRs of randomized controlled trials investigating the effects of Baduanjin were identified. A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2) checklist, Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement, and Grading of Recommendations Assessment, Development and Evaluation (GRADE) system were applied to evaluate the quality of the SRs.ResultsTen SRs were identified. All SRs were judged as critically low methodological quality by the AMSTAR-2 checklist. The total PRISMA score of the included SRs ranged from 15 to 21, and the mean score was 18.60 (1.90), indicating that all SRs had partial reporting deficits. Sixty outcomes were reported in the included studies, of which 25 (41.67%) were judged as low quality, and 34 (56.67%) as very low quality according to the GRADE system, indicating that the overall evidence quality of outcomes was not high.ConclusionBaduanjin seems to be an effective therapy for diabetes in improving glucose and lipid metabolism, mental health, quality of life, and waist-hip ratio (WHR). The overall quality of the SRs was less than optimal. This conclusion should be treated with caution, and researchers should conduct higher-quality clinical studies following AMSTAR-2checklist, PRISMA statement, and GRADE system in the future. 相似文献
96.
临床见习是临床实践教学的重要组成部分,是培养和提高医学生应用所学理论知识进行逻辑思维与临床实践综合运用能力的重要阶段,是实现医学生向实习医生角色转变的必须过程,同时也是提高医学生理论知识水平和临床实践技能的传统教育模式之一,在医学教学中起着承前启后的作用。使医学生较好地完成从学生到医生、从书本到病房、从校园到社会之间这一重要过渡阶段。 相似文献
97.
长效β2受体激动剂班布特罗对哮喘患者肺功能影响的观察 总被引:6,自引:0,他引:6
目的:了解班布特罗对哮喘患肺功能的影响。方法:选择50例患,治疗组(25例),给予班布特罗20mg每晚1次口服。对照组(25例),给予美喘清50μg日2次口服,疗程4周,随访2周,以用药前后PEF、FEV1、FVC变化为观察指标,结果:治疗组用2周肺功能即有改善,清晨PEF显提高(P<0.05),用药4周时改变最明显(P<0.01),对照组用药后清晨PEF稍有提高,但与用药相比差别不显,结论:班布特罗睡前常规服用可明显提高PEF,控制夜间哮喘发作,是安全而有效的长效支气管扩张药物。 相似文献
98.
Study on the Genotype of Extended-spectrum Beta-lactamases Mediated by Plasmid in Southern China 总被引:1,自引:0,他引:1
Alongwiththewidespreaduseoftheextended spectrum beta lactamase(ESBL)antibioticswithinlast20years, theemergenceofESBLs producingstrainsamongmembers ofthefamilyEnterobacteriaceaehasbecomeaworldwide problem.TheESBLsdescribedtodatebelongtotheBush group2orAmbl… 相似文献
99.
100.
目的 构建人成纤维细胞激活蛋白(FAP)过表达慢病毒载体,转染口腔鳞状细胞癌(OSCC)细胞株SCC9,构建稳定过表达FAP的OSCC细胞株。方法 采用聚合酶链反应(PCR)技术获得FAP片段,利用基因重组技术构建过表达FAP的慢病毒载体,包埋病毒并收集上清液感染SCC9细胞株,通过流式细胞荧光分选技术(FACS)进行筛选,获得稳定过表达FAP的SCC9细胞株。结果 对阳性克隆进行酶切鉴定和基因测序证明FAP的慢病毒载体构建成功,实时荧光定量PCR和Western blot检测结果证明成功构建稳定过表达FAP的SCC9细胞株。结论 本研究有助于获得纯化FAP蛋白,为进一步研究FAP在OSCC发生发展过程中的机制奠定基础。 相似文献