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951.
952.
To examine the effect of chronically elevated CO(2) on excitability and function of neurons, we exposed mice to 8 and 12% CO(2) for 4 wk (starting at 2 days of age), and examined the properties of freshly dissociated hippocampal neurons obtained from slices. Chronic CO(2)-treated neurons (CC) had a similar input resistance (R(m)) and resting membrane potential (V(m)) as control (CON). Although treatment with 8% CO(2) did not change the rheobase (64 +/- 11 pA, n = 9 vs. 47 +/- 12 pA, n = 8 for CC 8% vs. CON; means +/- SE), 12% CO(2) treatment increased it significantly (73 +/- 8 pA, n = 9, P = 0.05). Furthermore, the 12% CO(2) but not the 8% CO(2) treatment decreased the Na(+) channel current density (244 +/- 36 pA/pF, n = 17, vs. 436 +/- 56 pA/pF, n = 18, for CC vs. CON, P = 0.005). Recovery from inactivation was also lowered by 12% but not 8% CO(2). Other gating properties of Na(+) current, such as voltage-conductance curve, steady-state inactivation, and time constant for deactivation, were not modified by either treatment. Western blot analysis showed that the expression of Na(+) channel types I-III was not changed by 8% CO(2) treatment, but their expression was significantly decreased by 20-30% (P = 0.03) by the 12% treatment. We conclude from these data and others that neuronal excitability and Na(+) channel expression depend on the duration and level of CO(2) exposure and maturational changes occur in early life regarding neuronal responsiveness to CO(2). 相似文献
953.
Hui Guo Cuncai Wang Zhen Liu Huayong Gu Yuwen Li Li Zhao Ranran Hou Jiajia Zhu Harvey Ho Zhihui Hao 《Biopharmaceutics & drug disposition》2018,39(8):403-407
Although the study of bioequivalence waivers in humans is already well‐established, their application and translation into animals, which are complicated by differences in physiology, have only recently become subjects of interest. The main purpose of this paper is to quantify the liquid volume affecting drug dissolution in pig stomachs. We used magnetic resonance imaging (MRI) to scan 18 Bama miniature pigs weighing 15, 30 or 50 kg. Amira 6.0.1 software was used for 3D image processing. We found that the gastric fluid volume had a linear relationship with the weight of pig (R2 = 0.9935) over this weight range. The pig weight, therefore, could be used as a surrogate for the fasted gastric fluid volume. After combining data of gastric fluid secretion and drinking water volumes, our results could be used as a reference for the evaluation of oral drug absorption in pigs. 相似文献
954.
Feng Li Wenqiang Guo Li Wu Tianjiao Zhu Qianqun Gu Dehai Li Qian Che 《Archives of pharmacal research》2018,41(1):30-34
Three new diketopiperazine derivatives (DKPs), saroclazines A–C (1–3) along with three known DKPs (4–6) were isolated from mangrove-derived fungi Sarocladium kiliense HDN11-84. Saroclazines A–B (1 and 2) possessed a free amide structure, which was first found in sulfur-containing aromatic DKPs. Their structures were elucidated by NMR, HRESIMS and X-ray. The cytotoxic activity of new compounds (1–3) was tested against HeLa cell lines, among which compound 2 showed an IC50 value of 4.2 µM. 相似文献
955.
Hyung Sik Kim Jin Woo Lee Hari Jang Thi Phuong Linh Le Jun Gu Kim Moon Soon Lee Jin Tae Hong Mi Kyeong Lee Bang Yeon Hwang 《Archives of pharmacal research》2018,41(2):192-195
A new phenolic amide, named cis-terrestriamide (7), together with ten known compounds (1–6, 8–11), were isolated from the methanolic extract of the fruits of Tribulus terrestris. The structure of 7 was elucidated on the basis of extensive analyses of 1D and 2D nuclear magnetic resonance spectroscopic and high resolution mass spectrometry data. Compounds 1, 2, 5, 6, 8, 9, and 11 exhibited inhibitory effects on the lipopolysaccharide-stimulated nitric oxide production in RAW 264.7 cells, with IC50 values of 18.7–49.4 μM. 相似文献
956.
Hong Su Yafei Wang Yuanliang Gu Linda Bowman Jinshun Zhao Min Ding 《Journal of applied toxicology : JAT》2018,38(1):3-24
With the rapid development of nanotechnology, potential applications of nanomaterials in medicine have been widely researched in recent years. Nanomaterials themselves can be used as image agents or therapeutic drugs, and for drug and gene delivery, biological devices, nanoelectronic biosensors or molecular nanotechnology. As the composition, morphology, chemical properties, implant sites as well as potential applications become more and more complex, human biosafety of nanomaterials for clinical use has become a major concern. If nanoparticles accumulate in the human body or interact with the body molecules or chemical components, health risks may also occur. Accordingly, the unique chemical and physical properties, potential applications in medical fields, as well as human biosafety in clinical trials are reviewed in this study. Finally, this article tries to give some suggestions for future work in nanomedicine research. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
957.
958.
959.
Chen Dong Ting Fu Juan Ji Zhenyu Li Zhifeng Gu 《Clinical and experimental pharmacology & physiology》2018,45(8):747-754
Rheumatism is a group of diseases, most of which are autoimmune diseases, that violate joints, bones, muscles, blood vessels and related soft tissue. As is well known, cytokines play a role in the pathogenesis of several rheumatic diseases, such as rheumatoid arthritis, spondyloarthritides, and systemic lupus erythematosus. Recently, the role of interleukin‐4 (IL‐4), which may participate in the mechanism of rheumatism, have been discovered. It is reported that IL‐4 takes part in the regulation of T cell activation, differentiation, proliferation, and survival of different T cell types. IL‐4 also has an immunomodulatory effect on B cells, mast cells, macrophages, and many cell types. A review of the literature on functions of IL‐4 in rheumatic diseases is presented. 相似文献
960.
Jian Hua Gu Rulin Qian Robert Chou Pavel V. Bondarenko Merrill Goldenberg 《Pharmaceutical research》2018,35(8):157