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91.
目的:寻求既经济又有效的造血生长因子样活性物质。方法:采用造血祖细胞体外培养与造血生长因子生物活性检测等实验血液学技术,检测胎肌培养上清液、骨液基质细胞培养上清液、胸腺细胞培养上清液与脾细胞培养上清液对造血祖细胞CFU-GM、BFU-E和CFU-Mix增殖分化的影响。结果胎肌培养上清液和对CFU-GM和CFU-Mix的体外地产殖与分化有明显刺激作用。而胸腺与脾细胞条件培养上清液对BFU-E的生长有显著促进作用。结论:胎肌培养上清液中可能含GM-CSF样活性物质。而胸腺与脾细胞培养上清液具有较高IL-3样活性,可以利用组织与细胞培养上清液替代重组造血生长因子进行造血细胞的实验研究和临床诊断。 相似文献
92.
解脲支原体的生长条件研究 总被引:5,自引:0,他引:5
目的 探讨解脲支原体 (Uu)在液体培养基中的最佳营养条件和在固体培养基上形成菌落的最佳气体条件。方法 采用不同的pH值、不同的酵母及小牛血清含量配制解脲支原体培养基 ,将法国Merieum生产的培养基作对比研究。结果 解脲支原体生长最适pH值为 6.0~ 6.5 ;10 %酵母提取液、10 %小牛血清能加速解脲支原体的生长 ,90 %N2 、5 %~ 10 %CO2 能促进解脲支原体菌落生长。结论 本研究为改进解脲支原体的培养质量、开发高效的支原体培养基及药敏检测板提供实验依据 相似文献
93.
Yi-ting Cai Cheng-liang Xiong Tian-shu Liu Shi-liang Shen Jin-peng Rao Feng Qiu 《Andrologia》2021,53(8):e14144
This study aimed at the efficacy of sequential treatment of bone marrow-derived mesenchymal stem cell secretion for busulfan-treated azoospermia in mice. The conditioned media (CM) was obtained from bone marrow mesenchymal stem cells (MSCs) or 293 cells. Chemically induced azoospermia mice received 200 μl MSC-CM or 293-CM twice a week intravenously for three consecutive weeks. The histological assessment of spermatogenic recovery quantifying the expression of meiosis-associated genes, and Sertoli cell barrier functional factors were assessed. The characteristics of TM4 cells (Sertoli cell line) after pre-incubation of MSC-CM in vitro were also obtained. The MSC-CM group had the most spermatogenic colonies among the three groups (p < .05), but no spermatids were seen. Expressions of the meiosis-associated genes Dazl, Vasa, Miwi, Stra8, CyclinA1, Pgk2 and Scp3 in MSC-CM testis were remarkably higher compared with 293-CM and busulfan groups respectively (p < .05). The levels of Sertoli cell barrier functional factors, for example ICAM-1 and N-cadherin, were significantly increased during MSC-CM treatment (p < .05). Moreover, pre-incubation of MSC-CM particularly accelerated the CD54 (ICAM-1) and CD44 expressions of TM4 cells and promoted cell inherent adhesion. MSC-CM treatment can significantly improve the short-term restoration of spermatogonial structures of chemically induced azoospermia related to facilitating Sertoli cell adhesion integrity. 相似文献
94.
95.
Natural Convection Heat Transfer in a Porous Cavity with Sinusoidal Temperature Distribution Using Cu/Water Nanofluid: Double MRT Lattice Boltzmann Method 下载免费PDF全文
Hasan Sajjadi Amin Amiri Delouei Rasul Mohebbi Mohsen Izadi & Sauro Succi 《Communications In Computational Physics》2021,29(1):292-318
In this study, natural convection flow in a porous cavity with sinusoidal
temperature distribution has been analyzed by a new double multi relaxation time
(MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9
lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9
have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction
of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement
with the previous works, thus confirming the reliability the new numerical method
proposed in this paper. It is indicated that the heat transfer rate increases at increasing
Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and
phase deviation. However, the most sensitive parameter is the Rayleigh number. The
maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on
the heat transfer rate increases at increasing Rayleigh number, yielding a maximum
enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and
Ra=$10^5$, respectively. 相似文献
96.
BackgroundWhile anti-vaccine messages on social media have been studied for content, reach, and effectiveness, less is known about those who create and promote the messages. Online influencers, or ‘everyday people who are influential within their online social networks’, are viewed as trusted voices who are often making similar life decisions as their followers. Therefore, their experiences with and perspectives on health issues can be persuasive.MethodsWe collaborated with a formal network of online influencers to interview, using a semi-structured interview guide, vaccine hesitant influencer mothers about their views on vaccination; their process for developing health-related social media content; their motivation to promote anti-vaccine messages; and their opinions on current vaccination messaging. Prescreening ensured a diverse sample by race/ethnicity, age, education, number of children, and geographic residence. Interviews occurred by telephone, were audio recorded, and transcribed. Themes were generated independently by two coders using a deductive coding approach.ResultsWe interviewed 15 online influencer mothers from across the U.S. (average age 39 years old; all married; 13 Caucasian, 1 African American, 1 Hispanic). In some capacity, 5 of the 15 wrote about vaccination on their blog. Those who chose not to post anti-vaccine content did so for fear of alienating followers or having their platform be the site of combative discourse among readers. When researching their social media posts, the influencers did not trust mainstream sources of health information and relied on alternative sources and search engines.Implications: This exploratory study interviewed influential mothers who have the ability to spread anti-vaccine messages on social media. While most do not contribute to the anti-vaccine sentiment, understanding the motivation and practices of those that do assists the public health community in better understanding the online vaccination communication environment, leading to more effective messages to counterbalance anti-vaccine content on social media. 相似文献
97.
《Vaccine》2021,39(19):2684-2691
BackgroundIn response to growing anti-vaccine activism on social media, the #DoctorsSpeakUp event was designed to promote pro-vaccine advocacy. This study aimed to analyze Twitter content related to the event to determine (1) characteristics of the Twitter users who authored these tweets, (2) the proportion of tweets expressing pro-vaccine compared to anti-vaccine sentiment, and (3) the content of these tweets.MethodsData were collected using Twitter’s Filtered Streams Interface, and included all publicly available tweets with the “#DoctorsSpeakUp“ hashtag on March 5, 2020, the day of the event. Two independent coders assessed a 5% subsample of original tweets (n = 966) using a thematic content analysis approach. Cohen’s κ ranged 0.71–1.00 for all categories. Chi-square and Fisher’s exact tests were used to examine associations between tweet sentiment, type of account, and tweet content (personal narrative and/or statement about research or science). Accounts were analyzed for likelihood of being a bot (i.e. automated account) using Botometer.ResultsOf 847 (87.7%) relevant tweets, 244 (28.8%) were authored by a Twitter user that identified as a parent and 68 (8.0%) by a user that identified as a health professional. With regard to sentiment, 167 (19.7%) were coded as pro-vaccine and 668 (78.9%) were coded as anti-vaccine. Tweet sentiment was significantly associated with type of account (p < 0.001) and tweet content (p = 0.001). Of the 575 unique users in our dataset, 31 (5.4%) were classified as bots using Botometer.ConclusionsOur results suggest a highly coordinated response of devoted anti-vaccine antagonists in response to the #DoctorsSpeakUp event. These findings can be used to help vaccine advocates leverage social media more effectively to promote vaccines. Specifically, it would be valuable to ensure that pro-vaccine messages consider hashtag use and pre-develop messages that can be launched and promoted by pro-vaccine advocates. 相似文献
98.
99.
目的 分析微课指导下呼吸训练对肺癌根治术后肺功能的影响。方法 选取本院2016年1月—2018年1月收治的120例肺癌患者,以随机数字表法分为A组60例、B组60例,A组实施常规呼吸训练,B组在A组基础上给予微课指导,对比两组生活质量评分及肺功能指标。结果 B组术后第一秒最大呼出总量(FEV1)、用力深呼吸时肺活量(FVC)及FEV1/FVC分别为(2.08±0.29)L、(3.15±0.41)L、(69.78±12.55),高于A组的(1.74±1.14)L、(2.01±0.56)L、(64.44±12.02),(P<0.05);B组术后生活质量中社会领域、环境领域、生理症状、心理状态评分分别为(16.71±3.71)分、(17.99±3.36)分、(14.97±2.32)分、(16.44±3.85)分,高于A组的(13.58±3.45)分、(15.21±3.45)分、(13.12±2.64)分、(13.45±3.44)分,(P值均<0.05)。结论 微课指导下呼吸训练可有效改善肺癌根治术后肺功能指标及提高生存质量。 相似文献
100.
《Vaccine》2022,40(1):43-51
ObjectivesWith an uprising influence of social media platforms like Twitter and Instagram a multitude of worldwide accessible information is available. Since the beginning of COVID-19 pandemic the exchange of medical information about several topics related to this infectious disease and its vaccination has increased rapidly. The purpose of this investigation was to assess the content associated with COVID-19 vaccination and its side effects and evaluate its educational quality.MethodsWe conducted this retrospective study to investigate 600 Twitter and Instagram posts by #covidvaccinesideeffects due to number of ‘likes’, comments, type of post, language, its purpose and source. In addition, posts were evaluated due to educational quality by three examiners of different educational levels.ResultsThe majority of posts showed 0 to 50 “likes” and 0 to 5 comments in English language. A comparison between Twitter and Instagram by the influence of application showed significant differences in number of posts and “likes” or comments (p < 0.05). The major post type were texts for Twitter (251; 83.7%) and videos for Instagram (104; 34.7%). While a majority of posts by #covidvaccinesideeffects report about the occurrence of side effects, the majority of them were mild and general COVID-19 vaccination feedback during the first 4 months was positive. But, only 3 to 7% were rated by “excellent” educational and validatable content. Interrater reliability between all three examiners presented a high concordance with 89% (p = 0.001).ConclusionsThis study presents an analysis of quantity and quality of social media content according to COVID-19 vaccinations and its side effects. It supports the deduction that most of the content on Twitter and Instagram is shared by patients and unclear sources and thus is limited informative. Nevertheless, influence of social media on medical information especially during COVID-19 pandemic is increasing and practitioners have to face its effect on their patients. 相似文献