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51.
52.
目的 比较常规阻断缝合及早期松开阻断(EU)联合单层缝合(SLS)在腹腔镜肾部分切除(LPN)中"三连胜"及"五连胜"成功率的差异,评估改良技术的安全性及肾功能保护价值,寻找新技术的适应证.方法 纳入80例接受LPN患者,40例采用改良技术,40例采用常规技术.收集患者基线、围手术期及随访资料并进行分析.结果 两组并发症发生率、手术切缘阳性率、复发转移率及"三连胜"达成率差异无统计学意义.改良组"五连胜"达成率显著高于常规组,常规组内年龄过大、肿瘤直径过大及术前肾小球滤过率(eGFR)过低是导致"五连胜"失败的独立危险因素.肿瘤直径> 35 mm、年龄>64岁、术前eGFR< 73 ml/(min·1.73 m2)为导致"五连胜"失败临界值.结论 改良技术不增加各种并发症发生风险,在肿瘤体积较大、肾功能较差及高龄患者中使用该技术有利于患肾功能保护及"五连胜"目标的达成. 相似文献
53.
Near-infrared diffuse correlation spectroscopy/tomography (DCS/DCT) has recently emerged as a noninvasive measurement/imaging technology for tissue blood flow. In DCT studies, the high-dense collection of light temporal autocorrelation curves (g2(τ)) via fiber array are critical for image reconstruction of blood flow. Previously, the camera-based fiber array limits the field of view (FOV), precluding its applications on large-size human tissues. The line-shape fiber probe based on lens combination, which is predominantly used in current DCT studies, requires rotated-scanning over the surface of target tissue, substantially prolonging the measurement time and increasing the system instability. In this study, we design a noncontact optical probe for DCT based on collimating micro-lens fiber array, termed as FA-nc-DCT system. For each source/detector fiber, a single optical path was collimated by coupling with one micro-lens in the fiber array that is integrated in a square-shape base. Additionally, an 8×8 optical switch is used to share the hardware laser and detectors without spatial scanning. The FA-nc approach for the precise collection of g2(τ) curves was validated through a speed-varied phantom experiment and the human experiments of cuff occlusion, from which the expected value of the blood flow index (BFI) was obtained. Furthermore, the flow anomaly in the phantom and the ischemic muscle in human were accurately reconstructed from the FA-nc-DCT system, which is combined with the imaging framework based on the Nth-order linear algorithm that we recently created. Those outcomes demonstrated the great potential of FA-nc-DCT technology for fast and robust imaging of various diseases such as human breast cancers. 相似文献
54.
YIN Yue Qi LU Jing ZHOU Ying SHI Ling En YUAN De Fu CHEN Jian Shuang XUAN Yan HU Hai Yang ZHANG Zhi XU Xiao Qin FU Geng Feng WANG Bei 《Biomedical and environmental sciences : BES》2021,34(5):400-403,中插4
Integrase strand transfer inhibitors (InSTIs) have been widely used in recent years because of their high genetic barrier to resistance. The World Health Organization (WHO) has recommended dolutegravir (DTG)-containing regimens as the preferred first- and second-line antiretroviral therapy (ART) regimens for people living with human immunodeficiency virus (HIV)[1]. During the long-term treatment process, the appearance of drug resistance mutations to InSTIs is inevitable. A meta-analysis has shown that the resistance rate among InSTI treatment-experienced patients is 3.9% (Raltegravir, RAL), 1.2% (Elvitegravir, EVG), and 0.1% (DTG)[2]. However, resistance to InSTIs has not been reported in treatment-naive populations. 相似文献
55.
本文通过对特发性肺纤维化急性发作病因病机的分析,认为其病因为外邪或内伤引动肺络虚火,从阳化热,病机为“肺热”、“络瘀”;并结合其病因病机,探究归纳《温病条辨》中清络法和中药复方清络饮在论治特发性肺纤维化急性发作时的理论基础,为临床中论治特发性肺纤维化急性发作,改善患者症状提供新方法,为肺络病证治体系构建及应用提供新思路。 相似文献
56.
Ivan A. Pelevin Anton Yu. Nalivaiko Dmitriy Yu. Ozherelkov Alexander S. Shinkaryov Stanislav V. Chernyshikhin Alexey N. Arnautov Sergey V. Zmanovsky Alexander A. Gromov 《Materials》2021,14(10)
Aluminum matrix composites (AMC) are of great interest and importance as high-performance materials with enhanced mechanical properties. Al2O3 is a commonly used reinforcement in AMCs fabricated by means of various technological methods, including casting and sintering. Selective laser melting (SLM) is a suitable modern method of the fabrication of net-shape fully dense parts from AMC with alumina. The main results, achievements, and difficulties of SLM applied to AMCs with alumina are discussed in this review and compared with conventional methods. It was shown that the initial powder preparation, namely the particle size distribution, sphericity, and thorough mixing, affected the final microstructure and properties of SLMed materials drastically. The distribution of reinforcing particles tends to consolidate the near-melting pool-edges process because of pushing by the liquid–solid interface during the solidification process that is a common problem of various fabrication methods. The achievement of an homogeneous distribution was shown to be possible through both the thorough mixing of the initial powders and the precise optimization of SLM parameters. The strength of the AMCs fabricated by the SLM method was relatively low compared with materials produced by conventional methods, while for superior relative densities of more than 99%, hardness and tribological properties were obtained, making SLM a promising method for the Al-based matrix composites with Al2O3. 相似文献
57.
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59.
目的 探讨甲状腺癌根治术中不同途径显露喉返神经的应用情况.方法 根据随机数字表法将92例进行甲状腺癌根治术的患者随机分为对照组和观察组,每组46例.对照组采用甲状腺下动脉途径法显露喉返神经,观察组采用甲状腺最下动脉途径法显露喉返神经.比较两组患者寻找喉返神经的时间、术中出血量、手术时间、术后声音嘶哑和喉返神经损伤的发生率.结果 观察组患者寻找喉返神经的时间和手术时间均明显短于对照组患者,差异均有统计学意义(P﹤0.01).观察组患者的术中出血量明显少于对照组患者,差异有统计学意义(P﹤0.01).观察组患者术后声音嘶哑和喉返神经损伤的发生率均低于对照组患者,差异均有统计学意义(P﹤0.05).结论 甲状腺癌根治术中应用不同途径显露喉返神经,其效果存在差异.与甲状腺下动脉途径法相比,甲状腺最下动脉途径法能够明显缩短寻找喉返神经的时间和手术时间,减少术中出血量,降低术后声音嘶哑和喉返神经损伤的发生率,值得临床推广应用. 相似文献
60.
Seung Ki Min Se Kyung Lee Jinsun Woo Sung Mi Jung Jai Min Ryu Jonghan Yu Jeong Eon Lee Seok Won Kim Byung Joo Chae Seok Jin Nam 《JOURNAL OF BREAST CANCER》2021,24(1):75
PurposeTumor size and lymph node metastasis are important factors that contribute to the progression of breast cancer. We aimed to analyze the relationship between tumor size and lymph node metastasis molecular subtype and examine the effects of nodal metastasis on overall survival (OS).MethodsWe retrospectively reviewed the data of 16,552 patients who underwent breast surgery in Samsung Medical Center between 2000 and 2015. Information on tumor size (largest diameter of the invasive component), number of positive lymph nodes, and molecular subtype were obtained. We constructed a linear regression model to evaluate the relationship between tumor size and lymph node metastasis. To determine the effect of nodal metastasis on OS, we performed a Cox proportional regression analysis with Np/T (number of metastatic lymph nodes [n]/tumor size [cm]).ResultsThis study included 12,007 patients with a median follow-up of 62 months. The linear regression coefficients were 1.043 for luminal A, 1.024 for luminal B, 0.656 for HER2, and 0.435 for triple-negative breast cancer (TNBC) subtypes. No significant difference was observed in the coefficients between the luminal A and B subtypes (p = 0.797), while all other coefficients showed significant difference. After adjusting for other risk factors, the hazard ratio (HR) of Np/T for each subtype was significant for OS: luminal A (HR, 1.134; 95% confidence interval [CI], 1.097–1.171; p < 0.001), luminal B (HR, 1.049; 95% CI, 1.013–1.086; p = 0.007), HER2 (HR, 1.069; 95% CI, 1.014–1.126; p = 0.013), and TNBC (HR, 1.038; 95% CI, 1.01–1.067; p = 0.008).ConclusionThe incidence of lymph node metastasis differed according to molecular subtype. Luminal types have higher incidence of nodal metastasis than HER2 and TNBC. The HR of Np/T was highest in luminal A subtypes and lowest in TNBC subtypes. 相似文献