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排序方式: 共有6140条查询结果,搜索用时 171 毫秒
81.
《肿瘤代谢与营养电子杂志》2018,5(3):320-323
肿瘤相关性贫血是肿瘤相关性炎症或肿瘤相关治疗导致骨髓抑制(主要是放、化疗)引起的贫血。肿瘤相关性 贫血可以发生在肿瘤诊治的任何阶段,其发生与肿瘤类型、分期及治疗等因素密切相关。2012 年国内的调查显示,肿瘤相 关性贫血的发生率为60.83%,其中轻度贫血40.84%,中度贫血15.67%,重度贫血3.47%,极重度贫血0.84%。发病率较高的肿瘤分别为消化道癌、乳腺癌和肺癌等。研究显示,肿瘤相关性贫血会明显降低肿瘤患者的生活质量,影响治疗效果, 缩短生存期,增加死亡风险;而通过合理的治疗,纠正贫血后,可以改善患者的生活质量,提高生存率。肿瘤相关性贫血 的发病机制复杂,可能与肿瘤本身及其并发症(如肿瘤侵犯骨髓、溶血、失血、肿瘤相关性炎症等)、治疗手段引起的骨 髓抑制(化疗、放疗等)等有关。肿瘤相关性贫血的治疗目标为“提高生活质量,降低红细胞输注需求”。在病因治疗的 基础上,补充造血原料(铁剂、叶酸、维生素 B12 等),应用促红细胞生成素类药物及输红细胞治疗为其常用治疗手段。 相似文献
82.
Sébastien Djédjé Dano Pierre Manda Ardjourma Dembélé Ange Marie-Joseph Kouassi Abla Joel Henri Bibaud Julien Zroh Gouet Charles Bruno Ze Maria Sika 《Toxins》2013,5(12):2310-2323
Ochratoxin A (OTA) is a mycotoxin produced mainly by species of Aspergillus and Penicillium. Contamination of food with OTA is a major consumer health hazard. In Côte d’Ivoire, preventing OTA contamination has been the subject of extensive study. The current study was conducted to evaluate the influence of fermentation and drying materials on the OTA content in cocoa. For each test, 7000 intact cocoa pods were collected, split open to remove the beans, fermented using 1 of 3 different materials, sun-dried on 1 of 3 different platform types and stored for 30 days. A total of 22 samples were collected at each stage of post-harvesting operations. The OTA content in the extracted samples was then quantified by high-performance liquid chromatography. OTA was detected in beans at all stages of post-harvesting operations at varying levels: pod-opening (0.025 ± 0.02 mg/kg), fermentation (0.275 ± 0.2 mg/kg), drying (0.569 ± 0.015 mg/kg), and storage (0.558 ± 0.04 mg/kg). No significant relationships between the detected OTA level and the materials used in the fermentation and drying of cocoa were observed. 相似文献
83.
84.
Samantha L. Lipman Ned C. Rouze Mark L. Palmeri Kathryn R. Nightingale 《Ultrasound in medicine & biology》2018,44(4):897-908
Shear wave elasticity imaging (SWEI) characterizes the mechanical properties of human tissues to differentiate healthy from diseased tissue. Commercial scanners tend to reconstruct shear wave speeds for a region of interest using time-of-flight methods reporting a single shear wave speed (or elastic modulus) to the end user under the assumptions that tissue is elastic and shear wave speeds are not dependent on the frequency content of the shear waves. Human tissues, however, are known to be viscoelastic, resulting in dispersion and attenuation. Shear wave spectroscopy and spectral methods have been previously reported in the literature to quantify shear wave dispersion and attenuation, commonly making an assumption that the acoustic radiation force excitation acts as a cylindrical source with a known geometric shear wave amplitude decay. This work quantifies the bias in shear dispersion and attenuation estimates associated with making this cylindrical wave assumption when applied to shear wave sources with finite depth extents, as commonly occurs with realistic focal geometries, in elastic and viscoelastic media. Bias is quantified using analytically derived shear wave data and shear wave data generated using finite-element method models. Shear wave dispersion and attenuation bias (up to 15% for dispersion and 41% for attenuation) is greater for more tightly focused acoustic radiation force sources with smaller depths of field relative to their lateral extent (height-to-width ratios <16). Dispersion and attenuation errors associated with assuming a cylindrical geometric shear wave decay in SWEI can be appreciable and should be considered when analyzing the viscoelastic properties of tissues with acoustic radiation force source distributions with limited depths of field. 相似文献
85.
《Macromolecular chemistry and physics.》2017,218(23)
In order to accelerate the progress of the development of new self‐healing ionomers, a new pathway toward fully organic ionomers containing methacrylic acid and phosphate‐based functional groups, respectively, as well as butyl methacrylate as comonomer is presented in the current study. The well‐defined copolymer structures are synthesized using the reversible addition‐fragmentation chain transfer polymerization and further characterized by NMR, size exclusion chromatography as well as titration. Two different metal‐free ionomers as well as one reference K+ based ionomer are created and tested. The results of the detailed investigation by NMR, thermal analysis, and rheology are correlated with the scratch‐healing performance in order to identify trends and dependencies leading to preconditions for further improvements. 相似文献
86.
Kevin Messacar Stacey L Hamilton Andrea M. Prinzi Jessica C Mitchell Erik D Beil Elaine B. Dowell Samuel R. Dominguez 《Diagnostic microbiology and infectious disease》2019,93(1):22-23
The FilmArray Blood Culture Identification Panel was validated for nonblood sterile site specimens with clinical impact of rapid identification compared to conventional diagnostics. The panel accurately identified target organisms from 98% of positive broth cultures a median 1.1?day faster than conventional techniques (P?<?0.0001) with potential clinical impact in 22% of cases. 相似文献
87.
药用动物资源是中药资源的重要组成部分,是中医药发展的重要战略储备资源,在野生药用动物资源日渐匮乏的今天,大力开展药用动物人工养殖才能确保我国中医药产业的可持续发展。然而《中国药典》2015年版一部收载的106种药用动物中仅有22种(除家畜家禽外)有现行选育、养殖相关标准,共211项,其中除国家标准7项、行业标准(农业、水产)11项外均为地方标准,远远落后于同类型农业标准化程度,无法实现动物药材规范化生产。亟需对常见动物药材蟾酥、水蛭、全蝎等建立包括基础标准、产品标准、工艺过程标准、安全标准、环境保护标准、管理标准、工作标准在内的动物药材生产及产地加工技术标准体系,补充产业空白,从源头把控动物药材、动物类中药饮片及含有动物性成分中药产品质量。 相似文献
88.
89.
医院中药材库房管理小议 总被引:1,自引:0,他引:1
中药材的质量是关系其临床疗效的关键,影响中药材质量的因素很多,其中药材的贮藏是非常关键的一个环节.为保证中药材质量,医院库房管理应遵循"药材先进先出,及时巡查、发现问题及时处理,变质药材禁止入药,档案完备,管理规范"的原则. 相似文献
90.
Tzu‐Yu Peng Saiji Shimoe Naomi Tanoue Hiroyuki Akebono Takeshi Murayama Takahiro Satoda 《European journal of oral sciences》2019,127(3):269-275
With the rapid development of computer‐aided design/computer‐aided manufacturing (CAD /CAM ) systems, the application of zirconia in removable partial dentures is expected to expand. Clasps composed of zirconia should improve esthetics without inducing the risk of metal allergy. The aim of this study was to examine the fatigue resistance of yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) clasps for removable partial dentures. Yttria‐stabilized tetragonal zirconia polycrystal and cobalt‐chromium (Co‐Cr) alloy were prepared using CAD /CAM systems. Specimens were either of the semicircular type or of the flat type, with cross‐sectional areas of taper ratios of 0.50, 0.75, and 1.00. All specimens were tested using the cantilever test and the constant displacement fatigue test, and data were analyzed using ANOVA . During the cantilever test, the maximum displacement prior to fracture was greater than the required undercut, and the semicircular‐type specimen exhibited a higher fracture load than the flat type. None of the specimens displayed permanent deformation and showed almost the same degree of deformation after fatigue testing. A lower taper ratio was associated with lower average load values and greater displacement. Within the limitations of this study, it was possible to conclude that Y‐TZP provides the required undercut and adequate retentive force for removable partial denture clasps. Additionally, Y‐TZP and Co‐Cr alloy had almost the same degree of deformation even after the simulated lifespan of removable partial dentures. 相似文献