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排序方式: 共有68条查询结果,搜索用时 31 毫秒
1.
目的:克隆肿瘤坏死因子相关凋亡诱导配体(TRAIL)基因片段(114~281氨基酸残基)并构建原核表达载体。方法:取健康人外周血提取总RNA,设计合成引物并引入EcoR I和Xho I酶切位点,RT-PCR扩增TRAIL基因的胞外区片段,克隆入原核表达载体pGEX-6P-1中,经双酶切、PCR及测序鉴定阳性克隆。结果:从外周血cDNA中扩增出501 bp的目的片段,测序结果证实成功构建重组质粒pGEX-6P-1/TRAIL。结论:成功构建TRAIL基因的原核表达载体pGEX-6P-1/TRAIL,为肿瘤细胞的凋亡研究提供理论依据。  相似文献   
2.
While Inonotus obliquus produces a diverse range of bioactive metabolites in its natural habitats, it accumulates less in its submerged cultures. We show here that coculture of I. obliquus with Phellinus punctatus resulted in less production of mycelial biomass but an increased accumulation of phenolic compounds, melanins, and lanostane-type triterpenoids. Metabolites increased in production by coculture include phelligridin C, phelligridin H, methyl inoscavin A, inoscavin C, inoscavin B, davallialactone, methyl davallialactone, foscoparianol D, 21,24-cyclopentalanosta-3β,21,25-triol-8-en, lanosta-7,9(11),23-triene-3β,22,25-triol, and inotodisaccharide and melanins. Metabolites from coculture also showed an increased potential for scavenging free radicals and inhibiting the proliferation of HeLa 229 cells. Davallialactone, methyl davallialactone, and minor phenolic components are the major contributors for scavenging DPPH and hydroxyl radical in monoculture, and phelligridin C, phelligridin H, methyl inoscavin A, inoscavin C, methyl davallialactone, foscoparianol D, and inotodisaccharide are those for scavenging the tested radicals in coculture. Lanostane-type triterpenoids indicated limited roles in scavenging free radicals. Nearly all the detected metabolites correlate positively with inhibiting proliferation of HeLa 229 cells. Thus, coculture of I. obliquus with other fungi seems to be a cost-effective strategy for upregulating biosynthesis of bioactive metabolites.  相似文献   
3.
目的:探讨复发性自然流产与染色体罗伯逊易位间的关系。方法:采用人外周血淋巴细胞培养,常规G显带技术行染色体核型检查,并结合临床资料对其进行分析。结果:57对复发性自然流产夫妇中,检出罗伯逊易位染色体核型4例,检出率3.51%。结论:罗伯逊易位是导致复发性流产的重要原因之一,对复发性自然流产患者进行常规的染色体检查及遗传咨询具有一定的临床意义。  相似文献   
4.
A series of novel 1,3,4-oxadiazole thioether derivatives (compounds 9–44) were designed and synthesized as potential inhibitors of thymidylate synthase (TS) and as anticancer agents. The in vitro anticancer activities of these compounds were evaluated against three cancer cell lines by the MTT method. Among all the designed compounds, compound 18 bearing a nitro substituent exhibited more potent in vitro anticancer activities with IC50 values of 0.7 ± 0.2, 30.0 ± 1.2, 18.3 ± 1.4 μM, respectively, which was superior to the positive control. In the further study, it was identified as the most potent inhibitor against two kinds of TS protein (for human TS and Escherichia coli TS, IC50 values: 0.62 and 0.47 μM, respectively) in the TS inhibition assay in vitro and the most potent antibacterial agents with MIC (minimum inhibitory concentrations) of 1.56–3.13 μg/mL against the tested four bacterial strains. Molecular docking and 3D-QSAR study supported that compound 18 can be selected as dual antitumor/antibacterial candidate in the future study.  相似文献   
5.
Esophageal carcinoma (EC) is an aggressive and the third most common cancer of the digestive tract with poor prognosis. Replication protein A (RPA) is critically required for DNA replication and its elevated expression has been observed in many malignant tumors. In this study, we investigated the expression of RPA1 and RPA2, subunits of RPA, and assessed their prognostic value in EC patients. We analyzed immunohistochemically the expression of RPA1 and RPA2 proteins in 48 EC resection specimens in relation with clinicopathological parameters and survival. We observed a significant elevated (P < 0.001) RPA1 and RPA2 expressions (labeling index) in the tumor than adjacent non-tumor tissues. In addition, both RPA1 and RPA2 labeling index in lymph node metastasis patients was significantly higher (both P = 0.000) than patients without lymph node metastasis. However, RPA1 and RPA2 labeling index in early stage was significantly lower (P = 0.000 and P = 0.002, respectively) than that of late stage EC patients. Importantly, patient’s survival at early stage was significantly higher (P = 0.016) than late stage EC and lymph node metastasis and RPA1 expression was associated with adverse patient’s outcome in multivariate analysis (P < 0.05 and P < 0.00, respectively). In conclusion, RPA1 could be a useful prognostic indicator in patients with esophageal carcinoma and might be a future attractive therapeutic target for regulation by tumor suppressors.  相似文献   
6.
The present study evaluated the efficacy of intracoronary administration of verapamil to attenuate the no-reflow phenomenon following the primary percutaneous coronary intervention (PCI) in patients with the ST-segment elevation acute myocardial infarction (STEMI). A total of 201 patients with STEMI who underwent primary PCI within 12 h from the beginning of the heart attack were included. The no-reflow phenomenon was defined as substantial coronary anterograde flow of TIMI ≤2. Verapamil (100–200 μg) was injected into coronary artery immediately after no-reflow; the coronary arteriography was repeated later. Hundred and ninety-eight patients with STEMI successfully underwent primary PCI, and 246 stents were implanted with the average of 1.2 stents per patient. No-reflow occurred in 25 out of 198 patients (12.6 %). Twenty-one (84 %) patients developed the flow of TIMI ≥3 after intracoronary administration of verapamil, as revealed by repeated coronary angiography. Two patients developed transient hypotension which normalized without treatment within 3–5 min. Three patients showed sinus bradycardia, in one patient there was transient II sinoatrial block, and one patient developed type 1 atrioventricular block. All adverse effects were alleviated after intravenous injection of atropine (0.5–1 mg). In conclusion, the no-reflow phenomenon following primary PCI in patients with STEMI is significantly improved by intracoronary administration of verapamil which is useful to reduce cardiovascular events during operation.  相似文献   
7.
To develop a transurethral endoscopy technique of the transurethral seminal vesiculoscopy to examine and treat seminal vesicle disease. A total of 61 patients with seminal vesicle disease were diagnosed and treated with the transurethral seminal vesiculoscopy through the distal seminal tracts and vesicles. 58 cases were successfully treated using transurethral seminal vesiculoscopy via the seminal vesicles. The operation took 25 ~ 85 min, with an average of (35.6) mins. In this group, seven cases were diagnosed as ejaculatory orifice cyst, 14 cases had blood clots in the seminal vesicles, and nine patients had stones in the seminal vesicles. All patients were treated properly. Follow-up occurred at 3 months, with two cases showing post-operative discomfort in perineal region. One patient had recurrence with seminal vesiculitis, which improved with treatment. Four infertile patients had a significant increase in sperm count and ejaculation volume and two of these patients were able to naturally inseminate within seven to 18 months post-surgery. This approach enables a new endoscopic technique with the transurethral seminal vesiculoscopy to diagnose and treat seminal vesicle disease through the normal anatomic pathway which can be easily performed with few post-operative complications.  相似文献   
8.
The objective of this study was to compare surgical treatments for non-invasive bladder tumor. Hundred and forty patients with non-invasive bladder tumor were studied. Seventy-three patients were treated by transurethral resection of bladder tumor (TURBT) and Repeated-Transurethral Resection of Bladder Tumor (R-TURBT), while 67 by partial cystectomy. Operation time, blood loss, postoperative complications, and postoperative recurrence rate were better in the TURBT+R-TURBT group compared with the partial cystectomy group. Further, TURBT+R-TURBT offers advantages, such as simple surgical manipulation, less trauma, faster recovery, repeatedly performable procedure, and safety. In conclusion, this is an optimal therapy for treatment of non-invasive bladder tumor.  相似文献   
9.
The effects of melittin on growth and bacteriostasis of four pathogens were extensively investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results indicated that the melittin had a marked bacteriostatic effect on the four pathogenic bacteria. Among these, E. cacotowora was influenced most powerfully and quickly, the yeast and F. fulva were the second, and the S. aureus was inhibited by a low concentration but was killed by a high concentration. It was observed in the experiments that melittin killed pathogenic bacteria in three ways. One was by pore formation. After integrating melittin into the plasma membrane, a vacuole was formed then penetrated, resulting in bacterial content leakage. The vacuole also experienced plasmolysis and the growing cavity destroyed the membrane. A third effect was the formation of vacuoles in the cells which induced the pycnosis of the cytoplasm resulting in a cell death. The mechanism of melittin bacteriostasis was the result of integrating melittin with phospholipod double layers of the plasmalemma and the endomembranes.  相似文献   
10.
山东南部景观生态对策研究   总被引:10,自引:2,他引:8  
在对山东南部气候、地貌、土壤、植被等景观生态要素研究的基础上,以地貌和基质为基本线索、以植被为标志建立了该地区的景观生态分类系统.该系统为二级分类系统,包括7个景观型、17个景观亚型,其中,景观型根据植被(植被型或栽培植被型)划分,景观亚型根据地貌、植被(群系组或栽培组合)划分.以景观亚型或景观亚型的组合为基本单位,以1∶100万土壤图为基础底图,参考多种比例尺的卫星照片、植被图、土地利用图、地貌图等,编制了山东南部1∶100万景观生态类型图;在景观生态类型图上量算了各景观亚型的面积.据此详细分析了山东南部稀疏植被景观、常绿针叶林景观、落叶阔叶林景观、旱地作物景观、水旱轮作景观、湖泊景观等主要景观型的生态问题,提出了相应的生态对策  相似文献   
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