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71.
Soil improvement via MICP (microbially induced carbonate precipitation) technologies has recently received widespread attention in the geoenvironmental and geotechnical fields. The durability of MICP-treated samples remains a critical concern in this novel method. In this work, fiber (jute)-reinforced MICP-treated samples were investigated to evaluate their durability under exposure to distilled water (DW) and artificial seawater (ASW), so as to advance the understanding of long-term performance mimicking real field conditions, along with improvement of the MICP-treated samples for use in coastal erosion protection. Primarily, the results showed that the addition of fiber (jute) improved the durability of the MICP-treated samples by more than 50%. Results also showed that the wet–dry (WD) cyclic process resulted in adverse effects on the mechanical and physical characteristics of fiber-reinforced MICP-treated samples in both DW and ASW. The breakdown of calcium carbonates and bonding effects in between the sand particles was discovered to be involved in the deterioration of MICP samples caused by WD cycles, and this occurs in two stages. The findings of this study would be extremely beneficial to extend the insight and understanding of improvement and durability responses for significant and effective MICP treatments and/or re-treatments. 相似文献
72.
Reciprocal expression of trefoil factor‐1 and thyroid transcription factor‐1 in lung adenocarcinomas
73.
Hong YH Nishimura Y Hishikawa D Tsuzuki H Miyahara H Gotoh C Choi KC Feng DD Chen C Lee HG Katoh K Roh SG Sasaki S 《Endocrinology》2005,146(12):5092-5099
It has recently been discovered that G protein-coupled receptors (GPCR) 41 and 43 are characterized by having the short chain fatty acids acetate and propionate as their ligands. The objective of this study was to investigate the involvement of GPCR41, GPCR43, and their ligands in the process of adipogenesis. We measured the levels of GPCR41 and GPCR43 mRNA in both adipose and other tissues of the mouse. GRP43 mRNA expression was higher in four types of adipose tissue than in other tissues, whereas GPCR41 mRNA was not detected in any adipose tissues. A high level of GPCR43 expression was found in isolated adipocytes, but expression level was very low in stromal-vascular cells. Expression of GPCR43 was up-regulated in adipose tissues of mice fed a high-fat diet compared with those fed a normal-fat diet. GPCR43 mRNA could not be detected in confluent and undifferentiated 3T3-L1 adipocytes; however, the levels rose with time after the initiation of differentiation. GPCR41 expression was not detected in confluent and differentiated adipocytes. Acetate and propionate treatments increased lipids present as multiple droplets in 3T3-L1 adipocytes. Propionate significantly elevated the level of GPCR43 expression during adipose differentiation, with up-regulation of PPAR-gamma2. Small interfering RNA mediated a reduction of GPCR43 mRNA in 3T3-L1 cells and blocked the process of adipocyte differentiation. In addition, both acetate and propionate inhibited isoproterenol-induced lipolysis in a dose-dependent manner. We conclude that acetate and propionate short chain fatty acids may have important physiological roles in adipogenesis through GPCR43, but not through GPCR41. 相似文献
74.
The efficiency of interference of Potato virus X infection depends on the target gene 总被引:3,自引:0,他引:3
Takahashi S Komatsu K Kagiwada S Ozeki J Mori T Hirata H Yamaji Y Ugaki M Namba S 《Virus research》2006,116(1-2):214-217
RNA silencing is a natural defense response against viral infection. This phenomenon has been used to interfere with viral infections by exploiting fragments of viral genomes as sources of RNA silencing. Agrobacterium-mediated transient expression of a hairpin RNA derived from the TGBp1 gene of Potato virus X (PVX) induced RNA silencing of the TGBp1 gene and resulted in interference of PVX infection. The interference was induced in the infiltrated leaves but not in the upper non-infiltrated leaves. Transient expression of a CP hairpin RNA also induced interference of PVX. The TGBp1 hairpin RNA showed more efficient interference of PVX infection than the CP hairpin RNA. 相似文献
75.
Miki Taniguchi Noboru Murakami Hisae Nakamura Tetsuo Nasu Syusaku Shinohara Teiichi Etoh 《Brain research》1993,620(2):297-300
Melatonin release from the pineal cells of chicks, pigeons and crows (diurnal birds) in vitro was compared with that from owls ( a nocturnal bird). The pineal cells of diurnal birds secreted large amounts of melatonin during the dark period, whereas oowl pineal cells released virtually no melatonin over 24 h and did not respond to exogenous stimulant agents. Histological examination revealed that the owl pineal gland is very small and has a poor vascular network. These results suggest that the pineal gland of owls may have degenerated and is not involved in the circadian clock mechanism in this species. 相似文献
76.
Stella CL O'Brien JM Forrester KJ Barton JR Istwan N Rhea D Sibai BM 《American journal of perinatology》2008,25(6):325-329
Gestational hypertension (GHTN) and gestational diabetes mellitus (GDM) are both insulin resistance states. Perinatal outcome of GHTN or GDM alone are well established, but their combined effect on pregnancy outcome is underinvestigated. Our objective was to determine if pregnancies complicated by GHTN/GDM have higher rates of morbidity. We identified nulliparous women with singleton pregnancies delivering at 37 to 40 weeks of gestation from 1995 to 2004 from a database. Outcomes of pregnancies complicated by GHTN only, GDM only, or combined GHTN/GDM were compared with controls. Data analysis included the Mann-Whitney U test, the Kruskal-Wallis H test, and analysis of variance. Multivariate analysis was used to adjust for confounders. Of 14,880 patients, there were 11,349 controls, 2604 GHTN, 728 GDM, and 199 GHTN/GDM. After controlling for covariates, GHTN significantly increased cesarean section (C/S) rate (odd ratio [OR], 1.62; confidence interval [CI], 1.47 to 1.78), rates of admittance to the neonatal intensive care unit (NICU), and birth of large for gestational age (LGA) infants. GDM significantly increased C/S (OR, 1.42; CI 1.21 to 1.66), rates of NICU admission (OR, 1.32; CI, 1 to 1.75), birth of LGA (OR, 1.51; CI 1.14 to 1.98), and macrosomic infants (OR, 1.53; CI, 1.12 to 2.08). Rates of LGA infants (OR, 1.85; CI, 1.19 to 2.86) and C/S (OR, 2.03; CI, 1.52 to 2.71) were significantly increased with GHTN/GDM. We concluded that GHTN or GDM is associated with increased rates of adverse outcomes. Their coexistence further increases adverse perinatal outcomes. 相似文献
77.
78.
79.
Nicolaides AN Kakkos SK Griffin M Sabetai M Dhanjil S Thomas DJ Geroulakos G Georgiou N Francis S Ioannidou E Doré CJ;Asymptomatic Carotid Stenosis Risk of Stroke 《Vascular》2005,13(4):211-221
The aim of this study was to determine the effect of image normalization on plaque classification and the risk of ipsilateral ischemic neurologic events in patients with asymptomatic carotid stenosis. The first 1,115 patients recruited to the Asymptomatic Carotid Stenosis and Risk of Stroke (ACSRS) study with a follow-up of 6 to 84 months (mean 37.1 months) were included in this study. Duplex ultrasonography was used for grading the degree of internal carotid artery stenosis and for plaque characterization (types 1-5), which was performed before and after image normalization. One hundred sixteen ipsilateral ischemic hemispheric events occurred. Image normalization resulted in 60% of plaques being reclassified. Before image normalization, a high event rate was associated with all types of plaque. After image normalization, 109 (94%) of the events occurred in patients with plaque types 1 to 3. For patients with European Carotid Stenosis Trial (ECST) 70 to 99% diameter stenosis (equivalent to North American Symptomatic Carotid Endarterectomy Trial [NASCET] 50-99%) with plaque types 1 to 3, the cumulative stroke rate was 14% at 7 years (2% per year), and for patients with plaque types 4 and 5, the cumulative stroke rate was 0.9% at 7 years (0.14% per year). The results suggest that asymptomatic patients with plaque types 4 and 5 classified as such after image normalization are at low risk irrespective of the degree of stenosis. 相似文献
80.
Zhang Lu Wu Lili Liu Ximing Yoshitomi Hisae Ikeda Katsumi Negishi Hiroko Pan Yajing Sun Wen Qin Lingling Li Juan-E Xu Tunhai Liu Tonghua Gao Ming 《中医杂志(英文版)》2018,38(4):548-555