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101.
102.
皮肤鳞状细胞癌(cSCC)是角质形成细胞来源的恶性肿瘤之一。转录组是特定条件下细胞内全部转录产物的总和,包括编码mRNA和非编码RNA。研究发现,与正常细胞相比,鳞癌细胞在基因转录水平和模式上存在很大差异,具有不同转录表达谱。微小RNA(miRNA)可通过抑制转录产物的翻译,从而调控靶基因的表达,影响cSCC细胞的增殖、分化和凋亡等病理过程。越来越多的研究表明,miRNAs作为cSCC诊断、预测预后和治疗靶点的生物标志物,在临床上具有广阔的应用前景。本文通过回顾分析cSCC的miRNA表达谱,主要对其中经实验证实表达上调和下调的miRNAs在cSCC中的研究进展作一综述。  相似文献   
103.
The actinobacterium strain ABH26 closely related to Saccharothrix xinjiangensis, isolated from an Algerian Saharan soil sample, exhibited highly antagonist activity against Gram-positive bacteria, yeasts and filamentous fungi. Its ability to produce antimicrobial compounds was investigated using several solid culture media. The highest antimicrobial activity was obtained on Bennett medium. The antibiotics secreted by strain ABH26 on Bennett medium were extracted by methanol and purified by reverse-phase HPLC using a C18 column. The chemical structures of the compounds were determined after spectroscopic (1H NMR, 13C NMR, 1H-1H COSY and 1H-13C HMBC spectra), and spectrometric (mass spectrum) analyses. Two new cyanogriside antibiotics named cyanogriside I (1) and cyanogriside J (2), were characterized along with three known caerulomycins, caerulomycin A (3), caerulomycin F (4) and caerulomycinonitrile (5). This is the first report of cyanogrisides and caerulomycins production by a member of the Saccharothrix genus. The minimum inhibitory concentrations (MIC) of these antibiotics were determined against pathogenic microorganisms.  相似文献   
104.
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices.  相似文献   
105.
The incidence of obesity in the UK is increasing, meaning more women booking for antenatal care are obese. Obesity poses many additional risks to the mother and fetus during pregnancy, labour and the puerperium. Care of obese women should aim to reduce these risks. This article will discuss the risks associated with obesity in pregnancy and the management of obese women, from preconception through to completion of the postnatal period.  相似文献   
106.
OBJECTIVES: To assess the effectiveness and safety of additional bedtime H2‐receptor antagonists (H2RAs) in suppressing nocturnal gastric acid breakthrough (NAB) via a systematic review. METHODS: Eligible trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 2, 2004), MEDLINE (January 1966–June 2004), EMBASE (January 1980–June 2004) and CINAHL (January 1982–June 2004). Additional hand‐searching was conducted on the proceedings of correlated conferences, eight important Chinese journals and references of all included trials. All randomized controlled trials evaluating H2RAs for the control of NAB were eligible for inclusion. The systematic review was conducted using methods recommended by The Cochrane Collaboration. RESULTS: Only two randomized crossover studies, comprising 32 participants, met the inclusion criteria. Because the design, dosage and duration of the treatments were different between the studies, it was not possible to conduct meta‐analysis. There were no consistent conclusions found between the two included studies in evaluating H2RAs for the control of NAB. CONCLUSIONS: No implications for practice at this stage can be concluded. Appropriately designed large‐scale randomized controlled trials with long‐term follow up are needed to determine the effects of additional bedtime H2RAs in suppressing NAB.  相似文献   
107.
Condensation of thiourea 1 with diethyl malonate 2 in the presence of sodium methoxide furnished 4,6‐dihydroxy‐2‐mercaptopyrimidine 3 . Compound 3 on methylation with diazomethane followed by oxidation with H5IO6/CrO3 in ethyl acetate gave 4,6‐dimethoxy‐2‐methylsulphonylpyrimidine 5 . Compound 5 on condensation with 2‐mercapto‐6‐chlorobenzoic acid in the presence of a phase transfer catalyst, tetrabutylammonium bromide and sodium carbonate gave the title compound – pyrithiobac‐sodium 6 with an overall yield of > 35% starting from thiourea. Following the above standardized procedure, using [14C]‐thiourea in lieu of thiourea, 14C labelled product 6 , was synthesized with an overall radiochemical yield > 30% (with respect to [14C]‐thiourea) for further evaluations of environmental fate of 6 , in soils and plants. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
108.
目的探讨螺旋CT对于监测中央型肺癌术后局部复发及胸内淋巴结转移的价值。方法回顾性地对55例110人次中央型肺癌术后胸部增强螺旋CT资料进行分析。结果支气管残端或吻合口复发9例,12人次。胸内淋巴结26例33人次淋巴结短径≥1 cm,其中14例结合临床及CT诊断为淋巴结转移。结论对中央型肺癌术后复发的监测,螺旋CT是最好手段之一,但对肿大淋巴结性质的评价有一定局限性。  相似文献   
109.
经肺动脉与支气管动脉血管造影的CTA观察原发肺癌的血供   总被引:1,自引:0,他引:1  
目的用支气管动脉(BA)和肺动脉(PA)造影CTA观察肺癌血供情况。方法前瞻性观察6例支气管肺癌患者,分别行体循环动脉和肺动脉数字减影血管造影(DSA)后,留置BA导管与PA导管行CTBA与CTPA,观察BA与PA对肺癌的血供。结果CTPA上,无体动脉与左心强化的图像上肿瘤未见强化,有体动脉或左心强化的图像上见肿瘤边缘强化,CT强化值为10.0~45.6 Hu。CTBA上肿瘤部分明显强化,CT强化值为150.3~320.7 Hu,可见杂乱无章的肿瘤血管影,3例见纵隔淋巴结强化。结论本组病例观察表明原发性肺癌由BA为主的多发体循环动脉供血,未发现PA参与供血。  相似文献   
110.
目的评价螺旋CT对肝门胆管癌的诊断价值。方法13例肝门胆管癌行螺旋CT平扫及动态增强扫描,并与手术及病理对照分析。结果11例平扫表现为肝门区低密度软组织肿块;2例表现为肝门区胆管不规则增厚,管腔狭窄。增强扫描13例有延迟强化。结论螺旋CT扫描对肝门胆管癌的诊断具有重要意义。  相似文献   
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