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911.

As the most important construction features of ancient Chinese cities, the city walls nowadays have lost their function of enemy defense and turned to affect the urban structure and development. To clarify the impact of ancient city walls on modern urban development, this work was conducted to measure the differences of landscape types and levels between the inner and outer walls of three typical ancient Chinese cities with the help of geoinformatics materials and landscape ecology indices. The results of this research proved that city walls have great impact on landscape pattern. Specifically, the aggregation, fragmentation, diversity and evenness of landscape were strongly affected by well-preserved ancient city walls. By sorting out and consulting historical documents and China's “City Walls Protection Regulations”, we also found that city walls help the old city to retain its original style and design characteristics. The findings of this quantitative-analysis-based historical study can provide a theoretical basis for the protection of historical heritage and landscape design.

  相似文献   
912.
Moderately to well-preserved radiolarians have been extracted from nine greyish green and purplish-red bedded cherts in the mud-matrix mélange of the eastern Yarlung-Zangbo Suture Zone (YZSZ) at Jinlang Section, Zedong, southern Xizang (Tibet). Forty-two species belonging to 27 genera, including Middle Jurassic characteristic species such as Laxtorum (?) jurassicum Isozaki and Matsuda, Laxtorum (?) hichisoense Isozaki and Matsuda, Stichocapsa japonica Yao, Stichocapsa robusta Matsuoka, Parahsuum (?) magnum Takemura, Sella chrafatensis (El Kadiri), and Unuma typicus Ichikawa and Yao are recognized and three assemblages, Laxtorum (?) jurassicum Assemblage (Aalenian), Quarticella ovalis Assemblage (late Bajocian), and Stichocapsa robusta Assemblage (middle Bathonian) are established in ascending order. These assemblages can be well correlated to the Middle Jurassic Unitary Association (UA) Zones (Baumgartner et al., 1995) in west Tethys and coeval biozones in Japan and provide reliable age information for the Middle Jurassic stratigraphic correlation of the pelagic sediments along the YZSZ.  相似文献   
913.
Smoking and Candida albicans (Calbicans) infection are risk factors for many oral diseases. Several studies have reported a close relationship between smoking and the occurrence of Calbicans infection. However, the exact underlying mechanism of this relationship remains unclear. We established a rat infection model and a C. albicans-Leuk1 epithelial cell co-culture model with and without smoke exposure to investigate the mechanism by which smoking contributes to Calbicans infection. Oral mucosa samples from healthy individuals and patients with oral leucoplakia were also analysed according to their smoking status. Our results indicated that smoking induced oxidative stress and redox dysfunction in the oral mucosa. Smoking-induced Nrf2 negatively regulated the NLRP3 inflammasome, impaired the oral mucosal defence response and increased the oral mucosa susceptibility to Calbicans. The results suggest that the Nrf2 pathway could be involved in the pathogenesis of oral diseases by mediating an antioxidative response to cigarette smoke exposure and suppressing host immunity against Calbicans.  相似文献   
914.
Background aimsMesenchymal stromal cells and immunosuppressive factor IL-37 can both suppress concanavalin A (Con A)-induced hepatitis in mice. Endometrial regenerative cells (ERCs), novel types of mesenchymal-like stromal cells, possess powerful immunomodulatory effects and are effective in treating various diseases. The aim of this study was to explore the effects of ERCs in suppressing Con A-induced hepatitis and determine whether IL-37 overexpression could enhance the therapeutic effect of ERCs in this process.MethodsERCs were extracted from the menstrual blood of healthy female volunteer donors. The IL-37 gene was transferred into ERCs, and the expression of IL-37 in cells was detected by western blot and enzyme-linked immunosorbent assay. Hepatitis was induced by Con A in C57BL/6 mice that were randomly divided into groups treated with phosphate-buffered saline, ERCs, IL-37 or ERCs transfected with the IL-37 gene (IL-37-ERCs). Cell tracking, liver function, histopathological and immunohistological changes, immune cell proportions and levels of cytokines were measured 24 h after Con A administration.ResultsCompared with ERC or IL-37 treatment, IL-37-ERCs further reduced levels of liver enzymes (alanine aminotransferase and aspartate aminotransferase) and improved histopathological changes in the liver. In addition, IL-37-ERC treatment further reduced the proportions of M1 macrophages and CD4+ T cells and increased the proportion of regulatory T cells. Moreover, IL-37-ERC treatment resulted in lower levels of IL-12 and interferon gamma, and higher level of transforming growth factor beta.ConclusionsThe results of this study suggest that ERCs can effectively alleviate Con A-induced hepatitis. Furthermore, IL-37 overexpression can significantly enhance the therapeutic efficacy of ERCs by augmenting the immunomodulatory and anti-inflammatory properties of ERCs. This study may provide a promising strategy for treatment of T-cell-dependent hepatitis.  相似文献   
915.
916.
Recent reports showed that haematological and neurological expressed 1-like (HN1L) gene participated in tumorigenesis and tumour invasion. However, the expression and role of HN1L in breast cancer remain to be investigated. Here, bioinformatics, western blot and immunohistochemistry were used to detect the expression of HN1L in breast cancer. Wound healing, transwell assay, immunofluorescence assay and mass spectrum were used to explore the role and mechanism of HN1L on the migration and invasion of breast cancer, which was confirmed in vivo using a nude mice model. Results showed that HN1L was significantly over-expressed in breast cancer tissues, which was positively correlated with M metastasis of breast cancer patients. Silencing HN1L significantly inhibited the invasion and metastasis of breast cancer cells in vitro and lung metastasis in nude mice metastasis model of breast cancer. Mechanistically, HN1L interacted with HSPA9 and affected the expression of HMGB1, playing a key role in promoting the invasion and metastasis of breast cancer cell. These results suggested that HN1L was an appealing drug target for breast cancer.  相似文献   
917.
It has been reported that chemokine CX3CL1 can regulate various tumours by binding to its unique receptor CX3CR1. However, the effect of CX3CL1-CX3CR1 on the lung adenocarcinoma and lung squamous cell carcinoma is still unclear. Here, we showed that CX3CL1 can further invasion and migration of lung adenocarcinoma A549 and lung squamous cell carcinoma H520. In addition, Western blot and immunofluorescence test indicated CX3CL1 up-regulated the phosphorylation level of cortactin, which is a marker of cell pseudopodium. Meanwhile, the phosphorylation levels of c-Src and c-Abl, which are closely related to the regulation of cortactin phosphorylation, are elevated. Nevertheless, the src/abl inhibitor bosutinib and mutations of cortactin phosphorylation site could inhibit the promotion effect of CX3CL1 on invasion and migration of A549 and H520. Moreover, these results of MTT, Hoechst staining and Western blot suggested that CX3CL1 had no effect on the proliferation and apoptosis of A549 and H520 in vitro. The effects of CX3CL1 were also verified by the subcutaneous tumour formation in nude mice, which showed that it could promote proliferation and invasion of A549 in vivo. In summary, our results indicated that CX3CL1 furthered invasion and migration in lung cancer cells partly via activating cortactin, and CX3CL1 may be a potential molecule in regulating the migration and invasion of lung cancer.  相似文献   
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