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21.
肉毒毒素(Botulinum Toxin,BoNT)已成为现代医学最具多用途的治疗药物之一。通过将肉毒毒素注射到特定过度活动的肌肉中,可以阻断神经和肌肉之间的信号传导,引起肌肉的松弛性麻痹,从而达到治疗的功效。从业者应熟悉各类产品的特性,以实现安全有效地使用。除了已经上市的众多肉毒毒素产品外,目前还在开发其他新型制剂,这些产品将会进一步扩大肉毒毒素的适用范围,以及给患者提供更多的选择。  相似文献   
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肠易激综合征(Irritable bowel syndrome,IBS)是临床常见病、多发病,其治疗方法丰富,但部分患者疗效欠佳,发展成难治性IBS。目前国内外关于针灸治疗难治性IBS的临床随机对照试验尚不多见。本文立足试验方案设计的“PICOS”原则,从研究对象及诊断标准、干预措施、对照措施、结局指标四个方面入手,重点探讨针刺辅助治疗难治性肠易激综合征临床试验设计的关键要点。从选择特色优势病种、明确诊断标准、制定符合临床实际的干预方案、运用符合目标的安慰针刺、结合研究设计和目的选定结局指标几个角度,阐述试验相关环节设计的原因和思考。  相似文献   
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Introduction: There are at the minimum two major, quite different approaches to advance drug discovery. The first being the target-based drug discovery (TBDD) approach that is commonly referred to as the molecular approach. The second approach is the phenotype-based drug discovery (PBDD), also known as physiology-based drug discovery or empirical approach.

Area covered: The authors discuss, herein, the need for developing radiation countermeasure agents for various sub-syndromes of acute radiation syndromes (ARS) following TBDD and PBDD approaches. With time and continuous advances in radiation countermeasure drug development research, the expectation is to have multiple radiation countermeasure agents for each sub-syndrome made available to radiation exposed victims.

Expert opinion: The majority of the countermeasures currently being developed for ARS employ the PBDD approach, while the TBDD approach is clearly under-utilized. In the future, an improved drug development strategy might be a ‘hybrid’ strategy that is more reliant on TBDD for the initial drug discovery via large-scale screening of potential candidate agents, while utilizing PBDD for secondary screening of those candidates, followed by tertiary analytics phase in order to pinpoint efficacious candidates that target the specific sub-syndromes of ARS.  相似文献   

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BackgroundDistal radial access (DRA) has been proposed to improve procedure ergonomics and favor radial artery patency. Although promising data, nothing is known on evolving hand function after DRA.ObjectivesThis study sought to comprehensively evaluate hand function in patients undergoing DRA.MethodsReal-world patients undergoing DRA undertook a thorough multimodality assessment of hand function implementing multidomain questionnaires (Disabilities of the Arm, Shoulder and Hand and Levine-Katz), and motor (pinch grip test) and sensory (Semmes-Weinstein monofilaments test) examinations of both hands. All assessments were performed at preprocedural baseline and planned at 1-, 6-, and 12-month follow-up (FU). Adverse clinical and procedural events were documented too.ResultsData of 313 patients (220 men, age 66 ± 10 years) from 9 international centers were analyzed. The Disabilities of the Arm, Shoulder and Hand and the Levine-Katz scores slightly improved from baseline to FU (P = 0.008 and P = 0.029, respectively). Pinch strength mildly improved from baseline to FU (P < 0.001 for both the left and right hands). Similarly, touch pressure threshold appeared to faintly improve in both the left and right hands (P < 0.012 for all the sites). For both motor and sensory function tests, comparable findings were found for the DRA hand and the contralateral one, with no significant differences between them. Repeated assessment of all tests over all FU time points similarly showed lack of worsening hand function. Access-related adverse events included 19 harmless bleedings and 3 forearm radial artery and 3 distal radial artery occlusions. None affected hand function at FU.ConclusionsIn a systematic multidimensional assessment, DRA was not associated with hand function impairment. Moreover, DRA emerges as a safe alternative vascular access.  相似文献   
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Introduction and objectivesThe Spanish Society of Cardiology/Spanish Heart Foundation (SEC/FEC) annually awards grants for cardiovascular research projects. Our objective was to analyze the trend in these investments and their resulting scientific production from 2007 to 2012.MethodsA search of the publications funded by the SEC/FEC was carried out, according to the following inclusion criteria: publication in a journal indexed in MEDLINE or EMBASE, publication date after the grant, authorship by the principal investigator of the grant, and acknowledgment of SEC/FEC funding. The impact factor and subsequent citations of the articles were analyzed (Web of Science).ResultsA total of 235 grants were awarded (39/y) with an allocation of €3 854 300 (€642 383/y), 37% of them to women. In all, 122 publications resulted from 88 research projects (37%) funded by the SEC/FEC. Up to October 2017, these publications had received 2258 citations in subsequent studies in the Web of Science, with a mean of 18.5 and a median of 8 citations/study.ConclusionsDespite the economic crisis, the mean number and size of the grants awarded by the SEC/FEC increased in the period analyzed. Grants were awarded on an equal opportunity basis to men and women. The bibliometric impact of the funded projects is acceptable, although efforts should be made to improve it.  相似文献   
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The structural properties, elastic anisotropy, electronic structures and work function of D022-type Al3TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al3Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D022-type Al3TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al3La is the strongest, while that of Al3Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young’s modulus are further explained by the work function. Finally, the experimental design proves that D022-Al3Ta has an excellent strengthening effect.  相似文献   
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Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types.  相似文献   
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