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排序方式: 共有4234条查询结果,搜索用时 15 毫秒
71.
Yugui Zhang Jiangtao Niu Shujuan Zhang Xinlei Si Tian-Tian Bian Hongwei Wu Donghui Li Yujing Sun Jing Jia Erdan Xin Xingke Yan Yuefeng Li 《Pharmaceutical biology》2022,60(1):1237
ContextHedysari Radix Praeparata Cum Melle (HRPCM) and Astragali Radix Praeparata Cum Melle (ARPCM) are used interchangeably in clinics to treat spleen-qi deficiency (SQD) symptom mainly including gastrointestinal dysfunction and decreased immunity, which has unknown differences in efficacy.ObjectiveTo investigate the differences between HRPCM and ARPCM on intervening gastrointestinal- and immune-function with SQD syndrome.Materials and methodsAfter the SQD model was established, the Sprague–Dawley (SD) rats were randomly divided into nine groups (n = 10): normal; model; Bu-Zhong-Yi-Qi Pills; 18.9, 12.6 and 6.3 g/kg dose groups of HRPCM and ARPCM. Gastrointestinal function including d-xylose, gastrin, amylase vasoactive intestinal peptide, motilin, pepsin, H+/K+-ATPase, Na+/K+-ATPase, sodium-glucose cotransporter 1 (SGLT1), glucose transporter 2 (GLUT2) and immune function including spleen and thymus index, blood routine, interleukin (IL)-2, IL-6, interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α), immunoglobulin (Ig) M, IgA, IgG and delayed-type hypersensitivity (DTH) were detected. Finally, the efficacy differences were analysed comprehensively by the fuzzy matter-element method.ResultsIn regulating immune, the doses differences in efficacy between HRPCM and ARPCM showed in the high-dose (18.9 g/kg), but there were no differences in the middle- and low- dose (12.6 and 6.3 g/kg); the efficacy differences were primarily reflected in levels of IL-6, IFN-γ, TNF-α and IgM in serum, and the mRNA expression of IL-6 and IFN-γ in the spleen. In regulating gastrointestinal, the efficacy differences were primarily reflected in the levels of D-xylose, MTL, and GAS in serum, and the mRNA and protein expression of SGLT1 and GLUT2 in jejunum and ileum.Discussion and conclusionsHRPCM is more effective than ARPCM on regulating gastrointestinal function and immune function with SQD syndrome. Therefore, we propose that HRPCM should be mainly used to treat SQD syndrome in the future. 相似文献
72.
目的:了解婴幼儿智能发育状况,探讨影响智能发育落后的因素,以早期干预和指导。方法对500例在我院儿保门诊体检的3~30月婴幼儿进行DST发育筛查,对其发育商(DQ)进行统计,并对可疑与异常婴幼儿进行单项能区评价,分析其影响因素。结果500例婴幼儿检出可疑42例(8.4%),异常4例(0.8%);分析可疑与异常婴幼儿单项能区,检出运动落后34例(73.9%),社会适应落后26例(56.5%),智力落后12例(26.1%)。抚养方式对婴幼儿运动及社会适应有影响,分娩方式可能影响婴幼儿早期运动发育。结论 DST筛查能早期发现智能发育偏离儿童,有利于指导家长合理抚养和进行早期教育。 相似文献
73.
子痫前期(PE)是围生期母婴发病和死亡的主要原因之一。该病目前尚缺乏有效的治疗手段,终止妊娠是其唯一有效的治疗方法。预测和诊断PE的生物学标志物具有非常重要的临床意义。过去10年对PE发病机制的研究发现,生物学标志物在PE预测、诊断和治疗中发挥了重要作用。笔者总结了目前最新及最有可能用于临床预测和诊断PE的生物学标志物进行综述如下。 相似文献
74.
介绍了桌面虚拟现实技术在课件制作中的设计思路及实现方法。指出将虚拟现实技术与课件教学内容的知识点相整合,可强化课件的学习自主性和知识交互性,从而提高学习效率和教学质量。 相似文献
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78.
Xiaofen Liu Yuancheng Chen Haijing Yang Jian Li Jicheng Yu Zhenwei Yu Guoying Cao Xiaojie Wu Yu Wang Hailan Wu Yaxin Fan Jingjing Wang Jufang Wu Yi Jin Beining Guo Jiali Hu Xingchen Bian Xin Li Jing Zhang 《The Journal of infection》2021,82(2):207-215
ObjectivesPolymyxin B is a last-line antibiotic for multidrug-resistant gram-negative bacterial infections. However, limited safety and pharmacokinetic information is available. We investigated the safety and pharmacokinetics of intravenous polymyxin B in healthy subjects.MethodsAn open-label, single-dose clinical trial was conducted in healthy Chinese subjects. Polymyxin B (sulphate) was administered intravenously at 0.75 or 1.5 mg/kg (n = 10 per dose, 5 males and 5 females) to examine the safety and pharmacokinetics.ResultsOne female subject in the 1.5-mg/kg group discontinued due to abdominal pain during administration. The most frequently reported adverse events were perioral paraesthesia, dizziness, and numbness of extremities (7/10 subjects in the 0.75-mg/kg group, all subjects in the 1.5-mg/kg group). All neurotoxicity-related events dissipated without treatment within a maximum of 23 h. Notably, abdominal pain (3/5) and vulvar pruritus (2/5), colpitis (2/5) or abnormal uterine bleeding (1/5) were reported in female subjects receiving the 1.5-mg/kg dose. In the 0.75-mg/kg group, the total clearance, volume of distribution and half-life of polymyxin B were 0.028±0.002 L/h/kg, 0.219±0.023 L/kg and 5.44±0.741 h, respectively; similar values were observed in the 1.5-mg/kg group. Urinary recovery was 3.7 ± 1.1% and 8.1 ± 1.3% in the 0.75- and 1.5-mg/kg groups, respectively. Population pharmacokinetics of polymyxin B was consistent with a three-compartment model. The clearance and distribution of the central compartment were 0.027 L/h/kg and 0.071 L/kg, respectively.ConclusionsThis study is the first to examine the safety and pharmacokinetics of polymyxin B in healthy subjects. Our results highlight that acute toxicity is a dose-limiting factor for intravenous polymyxin B. 相似文献
79.
Ca2+-binding activity of a COOH-terminal fragment of the Drosophila BK channel involved in Ca2+-dependent activation 下载免费PDF全文
Bian S Favre I Moczydlowski E 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(8):4776-4781
Mutational and biophysical analysis suggests that an intracellular COOH-terminal domain of the large conductance Ca(2+)-activated K(+) channel (BK channel) contains Ca(2+)-binding site(s) that are allosterically coupled to channel opening. However the structural basis of Ca(2+) binding to BK channels is unknown. To pursue this question, we overexpressed the COOH-terminal 280 residues of the Drosophila slowpoke BK channel (Dslo-C280) as a FLAG- and His(6)-tagged protein in Escherichia coli. We purified Dslo-C280 in soluble form and used a (45)Ca(2+)-overlay protein blot assay to detect Ca(2+) binding. Dslo-C280 exhibits specific binding of (45)Ca(2+) in comparison with various control proteins and known EF-hand Ca(2+)-binding proteins. A mutation (D5N5) of Dslo-C280, in which five consecutive Asp residues of the "Ca-bowl" motif are changed to Asn, reduces (45)Ca(2+)-binding activity by 56%. By electrophysiological assay, the corresponding D5N5 mutant of the Drosophila BK channel expressed in HEK293 cells exhibits lower Ca(2+) sensitivity for activation and a shift of approximately +80 mV in the midpoint voltage for activation. This effect is associated with a decrease in the Hill coefficient (N) for activation by Ca(2+) and a reduction in apparent Ca(2+) affinity, suggesting the loss of one Ca(2+)-binding site per monomer. These results demonstrate a functional correlation between Ca(2+) binding to a specific region of the BK protein and Ca(2+)-dependent activation, thus providing a biochemical approach to study this process. 相似文献
80.
Transgenic alteration of Toll immune pathway in the female mosquito Aedes aegypti 总被引:3,自引:0,他引:3 下载免费PDF全文
Bian G Shin SW Cheon HM Kokoza V Raikhel AS 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(38):13568-13573
Reverse genetics is a powerful tool for understanding gene functions and their interactions in the mosquito innate immunity. We took the transgenic approach, in combination with the RNA interference (RNAi) technique, to elucidate the role of mosquito REL1, a homolog of Drosophila Dorsal, in regulation of Toll immune pathway in the mosquito Aedes aegypti. By transforming the mosquitoes with DeltaREL1-A or a double-stranded RNA construct of REL1 driven by the female fat body-specific vitellogenin (Vg) promoter with the pBac[3xP3-EGFP, afm] vector, we generated two different transgenic mosquito strains, one with overexpressed AaREL1 and the second with AaREL1 knockdown. Both strains had a single copy of the respective transgene, and the expression in both transgenic mosquitoes was highly activated by blood feeding. Vg-DeltaREL1-A transgenic mosquitoes activate Toll immune pathway in the fat body by blood feeding. The overexpression of both isoforms, AaREL1-A and AaREL1-B, in Vg-DeltaREL1-A transgenic mosquitoes resulted in the concomitant activation of Aedes Sp?tzle1A and Serpin-27A, independent of septic injury. The same phenotype was observed in the mosquitoes with RNAi knockdown of an Aedes homolog to Drosophila cactus, an IkappaB inhibitor of Drosophila Toll pathway. The effect of the transgenic RNAi knockdown of AaREL1 on mosquito innate immunity was revealed by increased susceptibility to the entomopathogenic fungus Beauveria bassiana and the reduced induction of Spz1A and Serpin-27A gene expression after fungal challenge. These results have proven that AaREL1 is a key downstream regulator of Toll immune pathway in the mosquito A. aegypti. 相似文献