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991.
新型冠状病毒肺炎疫情下,肿瘤患者免疫力低下,属于易感人群。营养不良是肿瘤患者最常见的营养问题,肿瘤患者作为特殊的人群值得被关注。本文从患者居家防护与饮食指导方面进行阐述,以期在特殊时期为肿瘤患者提供指导。  相似文献   
992.
Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic neoplasm that exhibits myelodysplastic and myeloproliferative characteristics with heterogeneous clinical and pathological features. There are limited publications on the ethnic and racial disparity of cytogenetics and genomics in CMML patients. This study aims to define the cytogenetic and molecular landscape in Hispanic CMML patients from Puerto Rico and explore its possible clinical significance. One hundred and eleven (111) Hispanic CMML patients from Puerto Rico were diagnosed in our institute from 2009 to 2018. Karyotypes were available in one hundred and seven (107) patients. Seventeen (17) patients had abnormal karyotypes (17/107, 16%). Compared to previously published data, Hispanic CMML patients in this study had significantly lower rates of overall cytogenetic abnormalities (16% vs 27–28%, p < 0.05) and trisomy 8 (2% vs 7%, p < 0.05). Among one hundred and eleven (111) Hispanic CMML patients, 40-gene myeloid molecular profile tests were performed in fifty-six (56) CMML patients. Gene mutations were identified in fifty-four (54) patients (96%). The most frequent mutated genes were: TET2, SRSF2, ASXL1, ZRSR2, DNMT3A, NRAS, CBL, and RUNX1. Twenty-nine (29) out of fifty-six (56) patients (29/56, 52%) had mutated TET2/wild type ASXL1 (muTET2/wtASXL1). Previous studies indicated that mutated ASXL1, DNMT3A, NRAS, RUNX1, and SETBP1 may associate with an unfavorable prognosis and muTET2/wtASXL1 may associate with a favorable prognosis in CMML patients. Compared to previously published data, Hispanic CMML patients from Puerto Rico in this study had significantly lower mutation rates in ASXL1 and SETBP1, and a higher rate of muTET2/wtASXL1. The findings raise the possibility of a favorable prognosis in Hispanic CMML patients.  相似文献   
993.
994.
This phase II randomized clinical trial aimed to assess the efficacy and toxicity of Endostar, an antiangiogenesis inhibitor, combined with concurrent chemoradiotherapy (CCRT) for locally advanced cervical cancer (LACC). Patients with LACC were randomly assigned to either CCRT plus Endostar (CCRT+E arm) or CCRT alone (CCRT arm). All patients received pelvic intensity-modulated radiation therapy (IMRT) and brachytherapy. Weekly cisplatin was administered concurrently with IMRT. Patients in the CCRT+E arm also received concurrent Endostar every 3 weeks for two cycles. The primary endpoint was progression-free survival (PFS) and acute toxicities. The exploratory endpoint was the impact of vascular endothelial growth factor receptor-2 (VEGFR2) expression on long-term survival. A total of 116 patients were enrolled. Patients in the CCRT+E arm and in the CCRT arm had similar acute and late toxicity profile. The 1- and 2-year PFS were 91.4% versus 82.1% and 80.8% versus 63.5% (p=0.091), respectively. The 1- and 2-year distance metastasis-free survival (DMFS) were 92.7% versus 81.1% and 86.0% versus 65.1% (p=0.031), respectively. Patients with positive VEGFR2 expression had significant longer PFS and overall survival (OS) compared with those with negative VEGFR2 expression. Patients in the CCRT+E arm had significantly longer PFS, OS, and DMFS than those in the CCRT arm when VEGFR2 expression was positive. In conclusion, CCRT plus Endostar significantly improved DMFS but not PFS over CCRT alone. The addition of Endostar could significantly improve survival for patients with positive VEGFR2 expression.  相似文献   
995.
996.
目的了解血友病患儿出血与关节病变之间的关系,为临床治疗和预后判断提供理论依据。方法选取2016年6月至2017年1月于首都医科大学附属北京儿童医院及成都市新世纪妇女儿童医院就诊的1~7岁重型血友病A且有关节出血记录的患儿,以患儿关节出血为研究关节,收集前3个月研究关节的出血次数,应用超声、X线、磁共振成像(MRI)和血友病关节健康评分(HJHS)评分系统对关节进行评估。将关节出血次数与超声、X线、MRI和HJHS评分进行相关性分析,并对超声、X线、MRI和HJHS评分间的相关性进行分析。结果1.共收集重型血友病A患儿18例,年龄(5.6±1.8)岁,共30个出血关节,中位年关节出血次数为4次(4~16次),中位年靶关节出血次数为8次(4~16次)。2.关节出血次数与超声、X线评估有相关性(r=0.390,P=0.033;r=0.517,P=0.008),与HJHS评估、MRI评估均无相关性(均P>0.05)。3.超声、X射线、HJHS和MRI两两之间均呈极显著正相关[r=0.815(超声与X线),r=0.510(超声与HJHS),r=0.812(超声与MRI),r=0.666(X线与HJHS),r=0.911(X线与MRI),r=0.781(HJHS与MRI),均P<0.01]。4.关节超声和/或MRI评估异常的关节中,出血次数与关节评估间均无相关性(P>0.05)。结论关节出血与关节评估获得的关节病变程度结果不一致,因此准确判断关节病变情况需综合评估关节结构、功能等,以便更加全面地指导血友病患儿的治疗。  相似文献   
997.
Nicosulfuron is one of the main sulfonylurea herbicides that have been widely used to protect maize crops. A total of 10 nicosulfuron-degrading strains were isolated from the intestine tract of earthworm Eisenia foetida. Among them, Bacillus velezensis CF57 with the highest degradation efficiency was selected and studied in detail. The degradation characteristics of CF57 showed that it was able to effectively degrade nicosulfuron in a wide range of temperature, pH, and a low inoculation amount, and the response surface analysis revealed that the optimum degradation conditions were 30.8 °C, pH 6.31, and inoculation amount 3.04%. Meanwhile, CF57 could degrade high-concentration nicosulfuron efficiently and posed a broad degradation spectrum of other sulfonylurea herbicides. Furthermore, the localization of degradation enzyme indicated that the nicosulfuron-degrading enzyme was an extracellular fraction. By analyzing the metabolites of nicosulfuron, it could be further determined that the degradation of nicosulfuron by strain CF57 was mainly through the extracellular enzyme, and its possible degradation pathway was mainly derived from the cleavage of the C–N bond of the sulfonylurea bridge. These results may provide new insights into bioremediation of nicosulfuron-contaminated environments and enrich the resources of degrading bacteria of sulfonylurea herbicides.  相似文献   
998.
目前专门对化学突触硬件实现的研究较少,采用FPGA芯片技术硬件实现化学突触,对神经元网络的硬件实现具有重要价值。运用DSP Builder软件,对以Hodgkin-Huxley神经元为突触前神经元和突触后神经元的化学突触数学模型进行建模。在DSP Builder模型的基础上,将化学突触的DSP Builder模型进行合理的拆分,然后分别将各个模块在FPGA所对应的软件环境下进行编译运行,最后下载到FPGA核心芯片中,硬件实现5种基于不同机理的化学突触模型。采用相关系数法,对仿真结果和硬件结果在同一个周期内的突触前神经元动作电位、突触后神经元动作电位以及突触电流的幅值进行对比,验证硬件实现的准确性。5种硬件实现的化学突触均可以较好地传递动作电位,但是各个模型消耗资源不同,模型3所消耗的内部乘法器资源(69%),约为模型5资源(31%)的2倍,表明突触模型数学复杂度越高,其消耗的乘法器资源越多。相关系数法的对比结果显示,模型3相关度最高,为0.791 3,模型4相关度最低,为0.693 5。虽然模型3数学复杂度高、硬件资源消耗多,但是其表现的生物性最好。硬件实现的5种突触模型均能较好地呈现化学突触的单向传递性,其中模型5硬件资源消耗少、相关度高,建议以其作为化学突触硬件实现的首选。  相似文献   
999.
Clinical Oral Investigations - To analyse evidence regarding the efficacy of periodontal regenerative procedures in intrabony defects in patients treated for aggressive periodontitis (AgP). A...  相似文献   
1000.
目的对比杂交技术与单纯腹腔镜技术在难复性腹股沟疝修补术中的应用价值。 方法将2015年1月至2017年12月廊坊市第四人民医院收治的单侧难复性腹股沟疝患者共60例纳入本研究,采用随机法分为2组。其中试验组患者30例,采用杂交技术;对照组患者30例,采用腹腔镜技术。对比2组患者手术时间、气腹持续时间、术中出血量、住院时间、住院费用、术后并发症等指标。 结果对照组1例患者因腹腔镜下难以分离还纳,后转为开放手术,淘汰出组,其余患者均顺利完成手术。试验组单侧难复性腹股沟疝患者住院时间、住院费用、术后发热情况、异物感发生情况分别为(5.00±0.85)d、(10 901.8±830.22)元、5例(16.7%)、2例(6.7%),与对照组(5.00±0.82)d、(11 116.45±813.73)元、6例(20.7%)、2例(6.9%)比较,差异无统计学意义(P均>0.05)。试验组单侧难复性腹股沟疝患者手术时间、气腹持续时间、术中出血量、血清肿发生情况分别为(57.00±5.81)min、(36.30±4.90)min、(21.00±3.80)ml、1例(3.3%),与对照组(72.90±3.66)min、(65±4.43)min、(56.7±8.69)ml、7例(24.1%)比较,差异均有统计学意义(t=-6.544、-6.698、-6.678、χ2=5.450,P均<0.05)。 结论相对于腹腔镜技术,杂交技术治疗难复性腹股沟疝可减少手术时间、气腹持续时间和术中出血量,降低术后血清肿的发生,不会增加术后疝复发等并发症的风险和住院费用,具有较高的临床应用价值。  相似文献   
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