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951.
雷州半岛鼠形动物种群动态研究 总被引:6,自引:0,他引:6
雷州半岛鼠形动物种群动态研究肖文忠,莫冠英(广东省湛江鼠疫防治研究所524037)DynamicResearchonRodentPopulationsinLeizhouPeninsula.¥XiaoWenzhong;MoGuanying(Zhanji... 相似文献
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A Brzecka H Zukowska R Mo?-Antkowiak 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1992,47(34-35):722-725
Symptoms and signs in 12 patients with severe obstructive sleep apnea (OSA) syndrome have been presented. The most common symptoms were snoring , increased motor activity during sleep and excessive daytime somnolence. The factors predisposing to OSA syndrome were obesity and anatomic abnormalities of the upper airway structure. In some cases the signs of OSA syndrome included hypertension, right heart failure, chronic alveolar hypoventilation and polycythemia. Polysomnography showed sleep fragmentation and the prevalence of light sleep stages. Obstructive sleep apneas repeated 73 +/- 23 times per hour of sleep. The mean apnea duration was 19 +/- 8 s. The mean arterial oxygen saturation during apnea was 72 +/- 14%. 相似文献
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Effects of sodium chloride (NaCl), guanidine hydrochloride (GuHCl), or sucrose on the viscoelasticity of sodium hyaluronate (NaHA) solutions were studied. NaCl and GuHCl decreased both storage and loss moduli, while sucrose increased both moduli. The critical concentration C* was determined as an inflection point in the plot of zero shear specific viscosity vs concentration for NaHA solutions with and without NaCl, GuHCl, or sucrose. It is suggested that sodium ions or guanidinium ions shield the electrostatic repulsion of NaHA molecules, hence reduce the coil dimension, and C* shifted to higher concentrations. However, sucrose enhances the entanglement coupling between NaHA molecules and retards the disentanglement of molecular chains or promotes to create hydrogen bonds, and then C* for NaHA solutions with sucrose shifts to lower concentrations. This is in agreement with the results of light scattering measurements in the presence of 0.2M NaCl. Both the radius of gyration and hydrodynamic radius of NaHA were reduced in dilute solutions by the addition of sucrose, and added sucrose enhances the interaction between NaHA monomer units. In the case of concentrated NaHA solution, such interactions result to increase the storage and loss moduli because of the enhancement of temporary network formation. © 1999 John Wiley & Sons, Inc. Biopoly 50: 23–34, 1999 相似文献
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Jian Guan Jinru Weng Qiaosheng Ren Chunbin Zhang Liantao Hu Wenjun Deng Shizhen Lu Xinyu Dong Weidong Li Yue Li Weiqun Wang 《Bioscience reports》2021,41(12)
CXCL3 plays extensive roles in tumorigenesis in various types of human cancers through its roles in tumor cell differentiation, invasion, and migration. However, the mechanisms of CXCL3 in head and neck squamous cell carcinoma (HNSCC) remain unclear. In our study, multiple databases were used to explore the expression level, prognostic value, and related mechanisms of CXCL3 in human HNSCC through bioinformatic methods. We also performed further experiments in vivo and in vitro to evaluate the expression of CXCL3 in a human head and neck tissue microarray and the underlying effect mechanisms of CXCL3 on the tumor biology of HNSCC tumor cells. The result showed that the expression level of CXCL3 in patients with HNSCC was significantly higher as compared with that in normal tissues (P<0.05). Kaplan–Meier survival analysis demonstrated that patients with high CXCL3 expression had a lower overall survival rate (P=0.038). CXCL3 was further identified as an independent prognostic factor for HNSCC patients by Cox regression analysis, and GSEA exhibited that several signaling pathways including Apoptosis, Toll-like receptor, Nod-like receptor, Jak-STAT, and MAPK signaling pathways may be involved in the tumorigenesis of HNSCC. CAL27 cells overexpressing or HNSCC cells treated with exogenous CXCL3 exhibited enhanced cell malignant behaviors, whereas down-regulating CXCL3 expression resulted in decreased malignant behaviors in HSC4 cells. In addition, CXCL3 may affect the expression of several genes, including ERK1/2, Bcl-2, Bax, STAT3, and NF-κB. In summary, our bioinformatics and experiment findings effectively suggest the information of CXCL3 expression, roles, and the potential regulatory network in HNSCC. 相似文献
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