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排序方式: 共有1219条查询结果,搜索用时 15 毫秒
1.
目的:建立黄芪与板蓝根2种根类药材醇沉絮体的分形维数测定方法。方法:分别以黄芪、板蓝根的水提醇沉絮体为研究对象,采用大津算法对醇沉絮体原始显微图像进行二值化处理,运用周长-面积法分别考察沉淀絮体取样体积、稀释倍数、图像放大倍数及图像采集位点数对分形维数的影响。结果:黄芪与板蓝根醇沉絮体均具有分形特征;确定这2个醇沉絮体取样体积在600~800μL,样品稀释至5~20倍,显微图像放大200倍或400倍,选取4个图像采集位点时,能够得到稳定可靠的醇沉絮体分形维数。结论:建立的测定方法稳定可行,可为根类药材醇沉絮体的分形理论研究提供参考。  相似文献   
2.
IntroductionElectrostatic precipitation Pressurized IntraPeritoneal Aerosol Chemotherapy (ePIPAC) has shown superior penetration depth and tissue uptake compared to standard PIPAC. We investigated the feasibility and objective tumor response to ePIPAC with 1 min of precipitation in patients with peritoneal metastasis (PM).Materials and methodsPatients with PM from various abdominal cancers were included in an amendment to the ongoing prospective PIPAC-OPC2 trial. Colorectal and appendiceal PM were treated with oxaliplatin, patients with PM from other primaries were treated with a combination of cisplatin and doxorubicin. Three ePIPAC procedures were planned in each patient including repeated peritoneal biopsies for response evaluation. After emission to the peritoneal cavity, the aerosolized chemotherapeutics were precipitated for 1 min followed by immediate exsufflation and abdominal closure. Histological regression from the first to the third ePIPAC was evaluated according to the Peritoneal Regression Grading Score (PRGS) and compared to data from the PIPAC-OPC1 trial. Complications and toxicities were recorded according to Dindo-Clavien and CTCAE.ResultsSixty-five ePIPAC procedures were performed in 33 patients (median 2, range 1–6). Ten patients were eligible for response evaluation based on biopsies from the first and third ePIPAC procedure. Four patients had disease progression, four patients had regressive disease, and two patients had stable disease according to PRGS. No life threatening adverse reactions and no mortality was observed following ePIPAC.ConclusionOne minute ePIPAC was feasible and safe, but the histological tumor response was insufficient compared to standard PIPAC directed therapy with 30 min passive diffusion time.  相似文献   
3.
The effects of anisotropic interfacial properties and heterogeneous elasticity on the growth and ripening of plate-like θ′-phase (Al2Cu) in Al-1.69 at.% Cu alloy are studied. Multi-phase-field simulations are conducted and discussed in comparison with aging experiments. The precipitate/matrix interface is considered to be anisotropic in terms of its energy and mobility. We find that the additional incorporation of an anisotropic interfacial mobility in conjunction with the elastic anisotropy result in substantially larger aspect ratios of the precipitates closer to the experimental observations. The anisotropy of the interfacial energy shows comparably small effect on the precipitate’s aspect ratio but changes the interface’s shape at the rim. The effect of the chemo-mechanical coupling, i.e., the composition dependence of the elastic constants, is studied as well. We show that the inverse ripening phenomenon, recently evidenced for δ’ precipitates in Al-Li alloys (Park et al. Sci. Rep. 2019, 9, 3981), does not establish for the θ′ precipitates. This is because of the anisotropic stress fields built around the θ′ precipitates, stemming from the precipitate’s shape and the interaction among different variants of the θ′ precipitate, that disturb the chemo-mechanical effects. These results show that the chemo-mechanical effects on the precipitation ripening strongly depend on the degree of sphericity and elastic isotropy of the precipitate and matrix phases.  相似文献   
4.
In the present study, 67 individuals from two families were analyzed to explore the efficacy of the ForenSeq DNA Signature Prep Kit for pairwise kinship analysis. Six types of pairwise relationships including 81 parent-offspring, 60 full siblings, 48 grandparent-grandchildren, 147 uncle/aunt-nephew/nieces, 97 first cousins and 190 non-relatives were generated from these two families and the corresponding likelihood ratio (LR) was calculated using either sequence-based or length-based STR genotype data (i.e., LRsequence and LRlength). In addition, 10,000 pairs of different relationships were simulated to estimate the system powers of the STRs and SNPs in this panel. The results showed that 54, 9 and 5 additional alleles were observed based on sequence for 27 autosomal STRs, 24 Y-STRs and 7 X-STRs, respectively, compared to those based on length information and 11 novel alleles were identified. Five mutations were found for 58 STRs in 81 parent-offspring but no mutations were observed for SNPs. For 27 autosomal STR loci, the LRs were increased from 9.20, 7.87, 2.01, 2.07, 0.42 for log10LRlength to 11.52, 10.12, 2.61, 2.60, 0.52 for log10LRsequence for paternity index (PI), full siblings index (FSI), grandparent-grandchild index (GI), uncle/aunt-nephew/niece index (UNI) and first cousins index (FCI), respectively. PI values for 94 SNPs separated more than those of 27 STRs if two individuals were non parent-offspring relatives. For the simulation study, the effectiveness was 1 for the parent-offspring relationship at the thresholds of t1 = − 4 and t2 = 4 and was 0.9998 for full siblings (t1 = − 2, t2 = 2). With an error rate of 0.42%, 93.02% of second degree relatives could be identified at the thresholds of t1 = − 1 and t2 = 1. However, the effectiveness was only 0.4300 for first cousins with a relatively high error rate of 2.68% (t1 = − 1, t2 = 1). In conclusion, STR typing according to the sequence information is more polymorphic, which increases the discrimination power for kinship testing. Compared to these 27 STR markers, 94 SNP markers in this panel have advantages in paternity testing especially when mutated STRs are involved or when a relative is an alleged parent. This panel is powerful enough to resolve paternity and full sibling testing. Most of the second degree relationships could be identified with low error rate while more markers are still needed for first cousins testing.  相似文献   
5.
The development of methods to reuse large volumes of plastic waste is essential to curb the environmental impact of plastic pollution. Plastic-reinforced cementitious materials (PRCs), such as plastic-reinforced mortar (PRM), may be potential avenues to productively use large quantities of low-value plastic waste. However, poor bonding between the plastic and cement matrix reduces the strength of PRCs, limiting its viable applications. In this study, calcium carbonate biomineralization techniques were applied to coat plastic waste and improved the compressive strength of PRM. Two biomineralization treatments were examined: enzymatically induced calcium carbonate precipitation (EICP) and microbially induced calcium carbonate precipitation (MICP). MICP treatment of polyethylene terephthalate (PET) resulted in PRMs with compressive strengths similar to that of plastic-free mortar and higher than the compressive strengths of PRMs with untreated or EICP-treated PET. Based on the results of this study, MICP was used to treat hard-to-recycle types 3–7 plastic waste. No plastics investigated in this study inhibited the MICP process. PRM samples with 5% MICP-treated polyvinyl chloride (PVC) and mixed type 3–7 plastic had compressive strengths similar to plastic-free mortar. These results indicate that MICP treatment can improve PRM strength and that MICP-treated PRM shows promise as a method to reuse plastic waste.  相似文献   
6.
陈云云  姚文栋  谢先泽  毛超  张钶  诸佳珍 《中草药》2020,51(21):5447-5453
目的 制备pH敏感释药的As2O3脂质体,并进行体外评价。方法 采用薄膜分散法制备含钙离子脂质体,然后用离子沉淀法孵育制备钙砷复合物脂质体(CaAs-LP)。测定CaAs-LP的粒径、Zeta电位及多分散系数(PDI);透射电子显微镜观察脂质体的形态;电感耦合等离子体发射光谱仪测定纳米药物的载药量与包封率;透析袋法考察其体外释药特性。噻唑蓝(MTT)法考察未载药脂质体及CaAs-LP对人源性乳腺癌MCF-7细胞、人源性脑胶质瘤U87细胞和人源性肝癌HepG2细胞的毒性;共聚焦显微镜考察U87细胞对CaAs-LP的摄取效率。结果 制备的CaAs-LP呈规整类球型,粒径约为(117.16±1.94)nm,包封率和载药量分别为(74.31±2.11)%、(8.31±0.13)%。体外释放研究表明,CaAs-LP具有明显的缓释以及pH响应释药特征。未载药的脂质体在MCF-7、U87、HepG2和L02细胞中的生物相容性良好;CaAs-LP抑制肿瘤细胞生长的作用较原药有所上升,半数抑制浓度(IC50)值分别为11.91、4.90、19.41、27.59 μmol/L。细胞摄取研究表明肝癌细胞对脂质体具有良好的摄取。结论 CaAs-LP具备显著的缓释以及pH响应释药的特性,在肿瘤治疗方面具有较好的应用前景。  相似文献   
7.
8.
目的比较5种布鲁氏菌核酸实时荧光PCR检测试剂盒的一致性和检出能力,为临床实验室选择检测方法和布鲁氏菌的诊断提供参考依据。方法选用经病原学检测确定为布鲁氏菌阳性的血液样本38份,健康人的血液样本24份,潘氏变形杆菌、溶藻弧菌、河弧菌、铜绿假单胞菌、肺炎克雷伯菌DNA各1份,使用5种试剂盒(编号A-E)分别进行核酸检测,比较5种试剂盒临床样本检测的一致性;选择1份阳性样本核酸用无RNA酶水梯度稀释得到5个浓度(浓度1:4453.13 fg/μL,浓度2:1113.28 fg/μL,浓度3:278.32 fg/μL,浓度4:69.58 fg/μL,浓度5:17.40 fg/μL),每个浓度使用5种试剂盒(编号A-E)分别进行3次检测,比较5种试剂盒的阳性检出率及批内重复性。结果5种试剂盒检测67份DNA样品的符合率稍有不同,试剂盒ABDE的符合率均为100%,试剂盒C的符合率为98.51%。批内重复性显示5种试剂盒在浓度1、浓度2、浓度3水平重复检测DNA的Ct值变异系数均<5%;在浓度1与浓度4梯度区间,试剂盒的阳性检出能力比较显示试剂盒A、B、D较高,为11/12,试剂盒C和E较低,为8/12。结论5种试剂盒的真实性和可靠性较好,灵敏度和符合率稍有差别,特异度均为100%;重复性较好,检测性能良好。部分试剂盒对弱阳性样本的检出能力不强,该类样本可使用多种试剂盒复核,以保障结果的准确性。  相似文献   
9.
目的探究与分析病区自备抽搐患儿急救箱在抢救抽搐患儿的临床应用。方法将河南省人民医院儿科一病区自2017年12月—2019年12月使用抽搐患儿急救箱前后的临床资料作为研究对象,将2017年12月—2018年12月(未使用急救箱)这一时间段的临床资料作为对照组(n=43例),将2019年1月—2019年12月(使用急救箱)这一时间段的临床资料作为观察组(n=40例),对比对照组与观察组的抢救应答时间、药品及物品的完整率、抢救落实及时率、护士长对护理人员的满意度、患儿家属对护理人员工作的满意度。结果观察组[(20.83±1.15)s]与对照组[(30.56±1.09)s]相比抢救应答时间缩短,差异有统计学意义(t=6.564,P<0.05)。观察组药品及物品的完整率(95.00%)与对照组(72.09%)相比,差异有统计学意义(χ2=7.755,P<0.05)。观察组抢救落实及时率(92.50%)相比对照组(67.44%)提高,差异有统计学意义(χ2=7.989,P<0.05)。观察组与对照组护士长对护理人员的满意度(例数)相比,差异有统计学意义(χ2=14.002,P<0.05);患儿家属对护理人员工作的满意度(例数),组间差异有统计学意义(χ2=6.030,P<0.05)。结论将病区自备抽搐患儿急救箱应用于抽搐患儿的抢救工作中能够明显的缩短抢救的应答时间,提高药品及物品的完整率、抢救落实及时率,提高护理人员以及患儿家属对护理人员工作的满意度。  相似文献   
10.
Loss of BRCA2 function stimulates prostate cancer (PCa) cell invasion and is associated with more aggressive and metastatic tumors in PCa patients. Concurrently, the receptor tyrosine kinase c‐kit is highly expressed in skeletal metastases of PCa patients and induced in PCa cells placed into the bone microenvironment in experimental models. However, the precise requirement of c‐kit for intraosseous growth of PCa and its relation to BRCA2 expression remain unexplored. Here, we show that c‐kit expression promotes migration and invasion of PCa cells. Alongside, we found that c‐kit expression in PCa cells parallels BRCA2 downregulation. Gene rescue experiments with human BRCA2 transgene in c‐kit‐transfected PCa cells resulted in reduction of c‐kit protein expression and migration and invasion, suggesting a functional significance of BRCA2 downregulation by c‐kit. The inverse association between c‐kit and BRCA2 gene expressions in PCa cells was confirmed using laser capture microdissection in experimental intraosseous tumors and bone metastases of PCa patients. Inhibition of bone‐induced c‐kit expression in PCa cells transduced with lentiviral short hairpin RNA reduced intraosseous tumor incidence and growth. Overall, our results provide evidence of a novel pathway that links bone‐induced c‐kit expression in PCa cells to BRCA2 downregulation and supports bone metastasis.  相似文献   
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