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1.
水分活度(简称a;)是食品和化妆品行业快速评价微生物风险和产品稳定性的重要指标之一。基于a;的原理深入分析a;对微生物生长的作用,综述目前药学研究中a;的应用现状,并借鉴食品、化妆品行业中a;的测量方法及应用方案,探讨a;用于中药临方制剂微生物风险控制的应用前景。此外,由于中药临方制剂对时限性的特殊要求,常规的细菌检测过程耗时过长,不能与其特性相适应,因而a;的引入将大大降低产品微生物检验的时限压力,有助于提高制剂的安全控制能力,为中药临方制剂的开发和应用提供高效可行的质控方案。  相似文献   
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周潇潇   《妇幼护理》2022,2(15):3418-3420
目的 研究将妊高症护理在产科护理中对提升母婴生活质量的影响。方法 2021 年 9 月至 2022 年 7 月在本院实施分娩的 110 例产妇,按照护理模式的不同将其分为对照组和观察组。对照组实施常规护理,观察组在实施常规护理工作的基础上应用 妊高症护理。比较两组的母婴分娩结局,新生儿状态和护理满意度。结果 观察组产妇难产发生率、子痫发生率、产后出血发 生率优于对照组(P<0.05)。观察组护理满意度高于对照组(P<0.05)。结论 将妊高症护理措施应用在产科护理,能够改善母婴 结局,提高护理满意度。  相似文献   
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The research and development of penicillin started with difficulty before 1949 and achieved certain results. In 1951, after the founding of the People's Republic of China, Zhang Weishen, as the only Chinese scientist who had been trained and worked in a penicillin research and development center in the United States for many years, overcame many difficulties and returned to China. In 1953, with the efforts of Zhang Weishen and his colleagues, China realized the industrialized production of penicillin, alleviating the urgent needs of the masses. Antibiotics has also become the first discipline to achieve major scientific and technological achievements after the founding of the New China. In the mid-1950s, the technical breakthrough in the localization of lactose substitutes marked the localization of the raw materials of the penicillin-producing culture medium, which paved the way for the industrialized production of penicillin with Chinese characteristics. Antibiotics have become one of the most widely used and affordable drugs for hundreds of millions of patients in China, and China has since ended the humiliating history of the “Sick Man of East Asia".  相似文献   
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In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol.  相似文献   
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BackgroundThe humoral immune response is pivotal to protect the host from Salmonella typhimurium (S. typhimurium) infection. Previously, we found that core fucosylation catalyzed by core fucosyltransferase (Fut8) could regulate the immune responses. However, the role of core fucosylation during S. typhimurium infection remains unclear.MethodsTo demonstrate the role of Fut8 in S. typhimurium infection, we infected Fut8+/+ and Fut8−/− mice using S. typhimurium. The production of antiserum against the S. typhimurium was detected. The expression of T and B cell activation-related genes during S. typhimurium infection was analyzed. The role of core fucosylation on CD4+ T-B cell interaction and B cell generation was investigated during S. typhimurium infection. The production of sIgA was compared between Fut8+/+ and Fut8−/− mice.ResultsCompared to Fut8+/+ mice, the number of S. typhimurium colonized in the cecum was markedly increased in Fut8−/− mice. The production of the IgG and sIgA specific for S. typhimurium was significantly decreased in Fut8−/− mice. Moreover, loss of Fut8 decreased the induction of Th2-type cytokines from splenic cells of Fut8−/− mice during S. typhimurium infection. In addition, we found that the core fucosylation regulated the interaction between B and T cells in the lipid raft formation.ConclusionCore fucosylation plays important roles in host defence against S. typhimurium infection.  相似文献   
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《Vaccine》2019,37(47):6987-6995
Vero cells are nowadays widely used in the production of human vaccines. They are considered as one of the most productive and flexible continuous cell lines available for vaccine manufacturing. However, these cells are anchorage dependent, which greatly complicates upstream processing and process scale-up. Moreover, there is a recognized need to reduce the costs of vaccine manufacturing to develop vaccines that are affordable worldwide. The use of cell lines adapted to suspension growth contributes to reach this objective.The current work describes the adaptation of Vero cells to suspension culture in different serum free media according to multiple protocols based on subsequent passages. The best one that relies on cell adaption to IPT-AFM an in-house developed animal component free medium was then chosen for further studies. Besides, as aggregates have been observed, the improvement of IPT-AFM composition and mechanical dissociation were also investigated.In addition to IPT-AFM, three chemically defined media (CD293, Hycell CHO and CD-U5) and two serum free media (293SFMII and SFM4CHO) were tested to set up a serum free culture of the suspension-adapted Vero cells (VeroS) in shake flasks. Cell density levels higher than 2 × 106 cells/mL were obtained in the assessed conditions. The results were comparable to those obtained in spinner culture of adherent Vero cells grown on Cytodex 1 microcarriers.Cell infection with LP-2061 rabies virus strain at an MOI (Multiplicity of Infection) of 0.1 and a cell density of 8 ± 0.5 × 105 cells/mL resulted in a virus titer higher than 107 FFU/mL in all media tested. Nevertheless, the highest titer equal to 5.2 ± 0.5 × 107 FFU/mL, was achieved in IPT-AFM containing a reduced amount of Ca++ and Mg++. Our results demonstrate the suitability of the obtained VeroS cells to produce rabies virus at a high titer, and pave the way to develop VeroS cells bioreactor process for rabies vaccine production.  相似文献   
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《Vaccine》2019,37(47):7003-7010
Control and prevention of rapid influenza spread among humans depend on the availability of efficient and safe seasonal and pandemic vaccines, made primarily from inactivated influenza virus particles. Current influenza virus production processes rely heavily on embryonated chicken eggs or on cell culture as substrate for virus propagation. Today’s efforts towards process intensification in animal cell culture could innovate viral vaccine manufacturing using high-yield suspension cells in high cell density perfusion processes. In this work, we present a MDCK cell line adapted to grow as single cell suspension with a doubling time of less than 20 h, achieving cell concentrations over 1 × 107 cells/mL in batch mode. Influenza A virus titer obtained in batch infections were 3.6 log10(HAU/100 µL) for total- and 109 virions/mL for infectious virus particles (TCID50), respectively. In semi-perfusion mode concentrations up to 6 × 107 cells/mL, accumulated virus titer of 4.5 log10(HAU/100 µL) and infectious titer of almost 1010 virions/mL (TCID50) were possible. This exceeds results reported previously for cell culture-based influenza virus propagation by far and suggests perfusion cultures as the preferred method in viral vaccine manufacturing.  相似文献   
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