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排序方式: 共有153条查询结果,搜索用时 15 毫秒
1.
Asako Yamamoto Lingli Yang Yasutaka Kuroda Jiao Guo Lanting Teng Daisuke Tsuruta Ichiro Katayama 《International journal of molecular sciences》2021,22(1)
As the outermost barrier of the body, skin is a major target of oxidative stress. In the brain, estrogen has been reported synthesized locally and protects neurons from oxidative stress. Here, we explored whether estrogen is also locally synthesized in the skin to protect from oxidative stress and whether aberrant local estrogen synthesis is involved in skin disorders. Enzymes and estrogen receptor expression in skin cells were examined first by quantitative real-time PCR and Western blot analyses. Interestingly, the estrogen synthesis enzyme was mainly localized in epidermal keratinocytes and estrogen receptors were mainly expressed in melanocytes among 13 kinds of cultured human skin cells. The most abundant estrogen synthesis enzyme expressed in the epidermis was 17β-hydroxysteroid dehydrogenase 1 (HSD17β1) localized in keratinocytes, and the most dominant estrogen receptor expressed in the epidermis was G protein-coupled estrogen receptor 1 (GPER1) in melanocytes. To investigate whether keratinocyte-derived estradiol could protect melanocytes from oxidative stress, cultured human primary epidermal melanocytes (HEMn-MPs) were treated with H2O2 in the presence or absence of 17β estradiol or co-cultured with HSD17β1 siRNA-transfected keratinocytes. Keratinocyte-derived estradiol exhibited protective effects against H2O2-induced cell death. Further, reduced expression of HSD17β1 in the epidermis of skin from vitiligo patients was observed compared to the skin from healthy donors or in the normal portions of the skin in vitiligo patients. Our results suggest a possible new target for interventions that may be used in combination with current therapies for patients with vitiligo. 相似文献
2.
T. Watanabe P. Chairoj H. Tsuruta W. Masarngsan C. Wongwiwatchai S. Wonprasaid W. Cholitkul K. Minami 《Nutrient Cycling in Agroecosystems》2000,57(1):55-65
Nitrous oxide (N2O) emission from fertilized maize fields was measured using a closed chamber at four experimental sites in Thailand. The average measured N2O flux from unfertilized plots through crop season was 4.16 ± 1.52, 5.05 ± 1.65, 5.25 ± 1.68 and 6.74 ± 2.95 g N2O-N m-2 h-1, at Nakhon Sawan, Phra Phutthabat, Khon Kaen and Chiang Mai, respectively. Increased N2O emissions by the application of nitrogen fertilizer were 0.22–0.44, 0.19–0.38%, 0.12–0.24 and 0.08–0.15% of the applied N, respectively. Compared to other data, N2O emission rate to applied nitrogen was not significantly different between the data of Thailand and the Temperate Zone. 相似文献
3.
Yuichiro?Furukawa Kazuyuki?InubushiEmail author Mochamad?Ali A.?M.?Itang Haruo?Tsuruta 《Nutrient Cycling in Agroecosystems》2005,71(1):81-91
Monthly measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes in peat soils were carried out and compared with groundwater level over a year at four sites (drained forest, upland cassava,upland and lowland paddy fields) located in Jambi province, Indonesia. Fluxes from swamp forest soils were also measured once per year as the native state of this investigated area. Land-use change from drained forest to lowland paddy field significantly decreased the CO2 (from 266 to 30 mg C m–2 h–1) and N2O fluxes (from 25.4 to 3.8 g N m–2 h–1), but increased the CH4 flux (from 0.1 to 4.2 mg C m–2 h–1) in the soils. Change from drained forest to cassava field significantly increased N2O flux (from 25.4 to 62.2 g N m–2 h–1), but had no significant influence on CO2 (from 266 to 200 mg C m–2 h–1) and CH4 fluxes (from 0.1 to 0.3 mg C m–2 h–1) in the soils. Averaged CO2 fluxes in the swamp forests (94 mg C m–2 h–1) were estimated to be one-third of that in the drained forest. Groundwater levels of drained forest and upland crop fields had been lowered by drainage ditches while swamp forest and lowland paddy field were flooded, although groundwater levels were also affected by precipitation. Groundwater levels were negatively related to CO2 flux but positively related to CH4 flux at all investigation sites. The peak of the N2O flux was observed at –20 cm of groundwater level. Lowering the groundwater level by 10 cm from the soil surface resulted in a 50 increase in CO2 emission (from 109.1 to 162.4 mg C m–2 h–1) and a 25% decrease in CH4 emission (from 0.440 to 0.325 mg C m–2 h–1) in this study. These results suggest that lowering of groundwater level by the drainage ditches in the peat lands contributes to global warming and devastation of fields. Swamp forest was probably the best land-use management in peat lands to suppress the carbon loss and greenhouse gas emission. Lowland paddy field was a better agricultural system in the peat lands in terms of C sequestration and greenhouse gas emission. Carbon loss from lowland paddy field was one-eighth of that of the other upland crop systems, although the Global Warming Potential was almost the same level as that of the other upland crop systems because of CH4 emission through rice plants. 相似文献
4.
Several research reports have indicated increasing dairy cow mortality in recent years. The objectives of this research were to characterize the phenotypic differences in mortality in the first 3 parities across 3 regions of the United States to estimate the heritability of mortality of Holstein cows across regions and parities, and to estimate genetic and environmental correlations between milk yield and mortality across parities and regions. Dairy Herd Information (DHI) milk yield and mortality data were obtained from 3 different US regions: the Southeast (SE), Southwest (SW), and Northeast (NE). A total of 3,522,824 records for the first 3 parities were used: 732,009 (SE), 656,768 (SW), and 2,134,047 (NE) from 1999 to 2008. Cows that received a termination code of 6—“Cow died on the dairy; downer cows that were euthanized should be included here”—were given a mortality score of 2 (dead), whereas all other codes were assigned a mortality score of 1 (alive). Average annual mortalities in the first 3 parities across regions ranged from 2.2 to 7.2%, with mortality frequency increasing with increasing parity across all regions and with the SE having the highest mortality frequency. For genetic analysis, a 2-trait (305-d milk yield and mortality) linear-threshold animal model that fitted fixed effects of herd-year (for 305-d milk yield), cow age, days in milk (in month classes), month-of-termination, and random effects of herd-year (for mortality), animal, and residual was implemented. The model was used to estimate variance components separately for each region and parity. Heritability estimates for mortality were similar for all regions and parities, ranging from 0.04 to 0.07. Genetic correlations between mortality and 305-d milk yield across the first 3 parities were 0.14, 0.20, and 0.29 in SE; −0.01, 0.01, and 0.31 in SW; and 0.28, 0.33, and 0.19 in NE. We detected an adverse genetic relationship between milk production and mortality; however, the moderate magnitudes of the genetic correlations suggest that indices that include both milk yield and mortality could be effective in identifying sires that would provide opportunities for minimizing death loss even when selecting for increased milk yield. 相似文献
5.
The purpose of this research is a quantitative analysis of movement patterns of dance,which cannot be analyzed with a motion capture system alone,using simultaneous measurement of body motion and biophysical information.In this research,two kinds of same leg movement are captured by simultaneous measurement;one is a leg movement with given strength,the other is a leg movement without strength on condition of basic experiment using optical motion capture and electromyography (EMG) equipment in order to quantitatively analyze characteristics of leg movement.Also,we measured the motion of the traditional Japanese dance using the constructed system.We can visualize leg movement of Japanese dance by displaying a 3D CG character animation with motion data and EMG data.In addition,we expect that our research will help dancers and researchers on dance through giving new information on dance movement which cannot be analyzed with only motion capture. 相似文献
6.
Muhammad Aamer Rafique Bhutta Yoshihiko Ohama Ken Tsuruta 《Construction and Building Materials》2011,25(2):779-784
The present study examines the applicability of polymer mortar panels using a methyl methacrylate (MMA) solution of waste expanded polystyrene (EPS) to develop effective recycling processes for the EPS, referring to the strength properties of a polymer-impregnated mortar panel with almost the same performance as commercial products. An MMA solution of EPS is prepared by dissolving EPS in MMA, and unreinforced and steel fiber-reinforced polymer mortars are mixed using the EPS-MMA-based solution as a liquid resin or binder. Polymer mortar panels (PMPs) using the EPS-MMA-based polymer mortars without and with steel fiber and crimped wire cloth reinforcements and steel fiber-reinforced polymer-impregnated mortar panel (PIMP) are prepared on trial, and tested for flexural behavior under four-point loading. The EPS-MMA-based PMPs are more ductile than the PIMP, and have a high load-bearing capacity. Consequently, they can replace PIMP in practical applications. 相似文献
7.
Records from Dairy Records Management Systems in Raleigh were used to estimate effects of bovine somatotropin (bST) treatment and to predict breeding values for milk production traits. The data comprised 5245 test-day records of bST-treated cows and 126,223 test-day records of untreated cows in first lactation for milk, fat, and protein yields. Fixed effects of bST treatment were estimated from test-day animal models with herd-test-date as another fixed factor. Percentage increases due to bST treatment ranged from 7 to 8% for test-day milk, fat, and protein yields. Random regression coefficients for additive genetic and permanent environmental effects were included in the model. To assess the potential for bias in genetic evaluations when some and not all cows are treated with bST, breeding values predicted by the test-day model with and without effects of bST treatment were compared for cows and sires. Correlations between breeding values predicted from models with and without effects of bST treatment were 0.99. However, relatively large bias was found for individual animals. This result suggests that bias in genetic evaluation caused by ignoring bST treatment may be significant. 相似文献
8.
Water-repellent surfaces were fabricated on blend sheets of poly(l-lactic acid)/poly(butylene succinate) with various blending ratios by the successive processing; (1) plasma etching, followed by (2) the hydrophobic plasma polymer coating. Rough morphology was formed effectively on the mosaic structured surface of blend sheets via the oxidative etching, and advanced water repellency was achieved after the thin membrane coating was synthesized with a hydrophobic plasma polymer coating by use of hexamethyldisiloxane or hexamethyldisilazane. High water repellency is expressed through the columnar hair-like structured model, where the air-water surface interaction in the voids is taken into account. 相似文献
9.
正伯利恒钢铁公司是20世纪的一个工业集团,在世界范围内运作工业设施。它于1857年在宾夕法尼亚州里海谷(Lehigh Valley)创立,逐渐占据了里海河沿线1 800英亩(约728hm2)的场地。1995年,伯利恒钢铁公司停止了炼钢业务,关闭了厂房,结束了当地悠久的工业历史,以及成千上万蓝领居民与工厂密不可分的生活模式。 相似文献
10.
N Egawa T Kamisawa Y Tu N Sakaki K Tsuruta A Okamoto 《Canadian Metallurgical Quarterly》1998,45(22):917-920
BACKGROUND/AIMS: Juxtapapillary diverticula (JPD) are considered to be associated with choledocholithiasis but not with cholecystolithiasis. However, there have been few comparative studies on the relationship between JPD and cholecystolithiasis under strict matching for sex and age. METHODOLOGY: Among 4542 consecutive ERCPs at Tokyo Metropolitan Komagome Hospital, 549 patients who were 63 years of age or older were enrolled in this study and were matched for sex and age. They were divided into two groups: with and without JPD. Firstly, the frequency of cholecystolithiasis was compared between the two groups. Next, we recruited 83 patients whose JPD size could be measured by the ERCP films and investigated the relationship between JPD size and gallstones. RESULTS: We found no correlation between JPD and the overall frequency of cholecystolithiasis. However, an analysis of 83 patients with measurable JPD revealed that the size of JPD was closely linked to the occurrence of cholecystolithiasis. The JPD size was statistically larger in patients with cholecystolithiasis than those without. Moreover, when the mean diameter of JPD was 20 mm or more, the incidence of cholecystolithiasis rose up to 73.3%, which was significantly greater compared to the incidence in patients without JPD (p< 0.05). CONCLUSION: A larger JPD may play a role in the formation of gallbladder stones. 相似文献