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1.
目的 探讨紫杉醇药物涂层球囊(P-DCB)成形术治疗症状性椎动脉开口狭窄的安全性和有效性。方法 回顾性分析2017 年12月至2019年6月经P-DCB成形术治疗的43例症状性椎动脉开口处狭窄的临床资料。结果 所有病人均完成介入治疗,成功率为100%。术后即刻狭窄率[(12.03±2.15)%]较术前[(86.32±10.26)%]明显降低(P<0.05)。围手术期发生动脉夹层1例,无其他并发症。随访12~16个月,平均13.5个月;症状改善43例,无变化例,症状改善率为95.3%(41/43);全部病人接受DSA或CTA随访,随访狭窄率[(16.1±3.12)%]与术后即刻无统计学差异(P>0.05);5例发生再狭窄,再狭窄率为11.6%。结论 P-DCB成形术治疗椎动脉开口狭窄具有较好的临床疗效。 相似文献
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中药材专业市场交易量逐渐下降,产地市场交易成为趋势。研究产地市场整合程度有利于了解中药材市场的运行情况,对于合理规划中药材生产和提高市场效率具有重要意义。选取大宗中药材金银花、枸杞子、板蓝根和太子参研究中药材市场整合程度,利用2013—2019年价格指数,运用协整检验、误差修正模型和格兰杰因果检验进行实证分析。结果表明,我国中药材产地市场长期整合程度较高;中药材产地市场的短期整合程度远不及长期整合程度。为此提出4点政策建议:完善中药材价格信息平台、打造非道地产区中药材优质品牌、加快建成中药材质量追溯体系和建设中药材现代物流体系。 相似文献
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Shogo Yamamoto Yutaka Midorikawa Genta Nagae Kenji Tatsuno Hiroki Ueda Mitsuhiko Moriyama Tadatoshi Takayama Hiroyuki Aburatani 《Cancer science》2020,111(2):601-609
Multiple hepatocellular carcinoma (HCC) is divided into two categories: intrahepatic metastasis (IM), which is a true relapse of HCC, and multicentric origin (MO), which is a second primary tumor. Clinical diagnosis of multiple HCC is usually made based on tumor location and/or time to recurrence; however, it is often difficult to distinguish the two types of multiple HCC. Using 41 matched pairs of multiple HCC specimens, we confirmed the accuracy of clinical diagnoses using exome sequence data and investigated the importance of discriminating the type of multiple HCC. Genomic analysis revealed that 18 (43.9%) patients diagnosed as having genomic IM had common mutations in a pair of HCC tumors with the main tumor of these patients being more progressive compared to those with genomic MO. The accuracy of clinical diagnosis based on lobe (Definition 1) and segment (Definition 2) were 68.3% and 78.0%, respectively. Intriguingly, recurrence ≥2 years after initial surgery for 3 patients was IM. The survival of patients with clinical IM was significantly shorter than for those with clinical MO based on both Definition 1 (P = 0.045) and Definition 2 (P = 0.043). However, mean survival was not different between the patients with genomic IM and those with MO (P = 0.364). Taken together, genomic analysis elucidated that liver cancer may spread more extensively and more slowly than previously thought. In addition, distinguishing multiple HCC as IM or MC may have provided biological information but was not of clinical importance with respect to patient prognosis. 相似文献
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Yu‑Xiang Zhang Zhong‑Chen Gao Ye‑Xin Liu Wei Li 《World Journal of Traditional Chinese Medicine》2020,6(4)
Background: As the demand for traditional Chinese medicinal materials increases in China and even the world, there is an urgent need for an effective and simple identification technology to identify the origin and quality of the latter and ensure the safety of clinical medication. Mineral element analysis and isotope finger-printing are the two commonly used techniques in traditional origin identification. Both of these techniques require the use of stoichiometric methods in the identification process. Although they have high accuracy and sensitivity, they are expensive and inefficient. In addition, near-infrared spectroscopy is a fast, nondestructive, and widely used identification technique developed in recent years, but its identification results are susceptible to samples’ states and environmental conditions, and its sensitivity is low. Hyperspectral imaging combines the advantages of imaging technology and optical technology, which can simultaneously access the image information and spectral information which reflect the external characteristics, internal physical structure, and chemical composition of the samples. Hyperspectral imaging is widely applied to agricultural product inspection, but research into its application in origin and quality identification of TCM materials is rare. Methods: In this study, the algorithm framework discriminative marginalized least squares regression (DMLSR) was used for feature extraction of frankincense hyperspectral data. The DMLSR with intraclass compactness graph and manifold regularization can efficiently learn the projective samples with higher separability and less redundant information than the original samples. Then, the discriminative collaborative representation with Tikhonov regularization (DCRT) was applied for classifying the geographical origin and level of frankincense. DCRT introducesthe discriminant regularization term and incorporates SID, which is more sensitive to the spectrum as the measurement method and is more suitable for the frankincense spectral data compared with SVM. Results: For the origin classification task, samples of all levels from each origin were, respectively, selected for three?way classification. We used 10-fold cross-validation to select a model parameter in the experiment. When obtaining the optimal parameters, we randomly selected the training set and testing set, where the training set accounts for 70% and the training set for 30%. After repeating this random process 10 times, we obtained the final average classification accuracy, which is higher than 90%, and the standard deviation fluctuation is usually small. For the level classification task, samples of each level from three origins were separately selected for multiclassification. We randomly selected the training set and testing set from each origin. The level classification results of the three origins are good on D4350 data, and the classification accuracy of each level is basically above 80%. Conclusion: Experiments and analysis show that our algorithm framework has excellent classification performance, which is stable in origin classification and has potential for generalization. In addition, the experiments show that in our algorithm framework, different classification tasks need to combine different data sources to achieve better classification and recognition, as the origin classification task uses frankincense’s D3000 data, and level classification task uses frankincense’s D4350 data. 相似文献
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目的:构建地乌药材基原物种系统鉴定体系,并对全国16个产地的地乌药材进行综合品质评价,为地乌药材产地选择及临床用药安全奠定基础。方法:使用传统鉴别方法结合DNA条形码核糖体DNA第二内部转录间隔区(ITS2)序列分子鉴定技术快速鉴别地乌药材真伪,并基于HPLC-UV对地乌药材中5个有效成分进行含量测定,采用Welch Ultimate XB-C18色谱柱(4.6 mm×250 mm,5μm),流动相乙腈-0.01%三氟乙酸溶液(30∶70),检测波长210 nm,柱温30℃,流速1.0 mL·min-1。结果:传统鉴别及DNA条形码快速鉴别技术均能准确鉴别地乌药材真伪。BLAST比对分析发现,16个产地地乌药材均与林荫银莲花Anemone flaccida具有最大相似度;基于多指标成分含量测定表明湖北恩施板桥镇的地乌药材中5个三萜皂苷类成分含量之和最高(10.59%),其次为贵州毕节赫章(6.28%)和湖北长阳都镇湾(5.64%)。结论:DNA条形码技术可作为地乌药材传统鉴定技术的有效补充,该鉴别体系可保障地乌药材基原准确及临床用药安全。HPLC多指标成分综合评价及聚类分析结果表明在本研究所涉及的产地中,湖北恩施、长阳、五峰,贵州毕节和重庆金佛山的地乌药材质量较优,可作为地乌药材的重要产地。 相似文献
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通过对中医古籍中有关升降散论述的文献梳理,全面探讨其内涵。本方是在大黄、僵蚕为雏形的基础上增加蝉蜕、姜黄而成方,几经易名,终在杨璿《伤寒瘟疫条辨》中为后人所熟知。本方广泛用于治疗瘟疫,以丸剂、散剂为主,方便携带,便于服用;重用大黄旨在祛邪、逐秽;应用时视人之体质强弱和量其毒之轻重而判断用药多寡,并辅以米酒、生蜜等以顾护正气。杨璿将其由治疗“热疫”的专方扩展为治疗“表里三焦大热”的通用方剂,扩大了本方治疗疾病范围。 相似文献