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991.
Seung Ho Baek Min-Chul Jang Moonho Son Si Wouk Kim Hoon Cho Young Ok Kim 《Journal of applied phycology》2013,25(4):1055-1064
The algicidal effects of the thiazolidinedione derivative TD49 on Heterosigma akashiwo and Chattonella marina (Raphidophyceae) were assessed, and the response of the planktonic community and environment to the algicide was evaluated in a microcosm, quantifying 12 L. The abundance of over 80 % of H. akashiwo and C. marina declined in a day significantly in microcosms to which TD49 was added (final concentration 2 μM), and this was correlated with an abrupt decline in the culture pH. The number of protists (i.e., ciliates) other than H. akashiwo and C. marina gradually increased with time in the TD49 treatments, implying that the decline in numbers of H. akashiwo and C. marina cells resulting from TD49 treatment was a major factor in the growth of the other organisms. However, TD49 may be toxic to aquatic zooplankton communities, even though it is a highly selective algicide for harmful algae bloom species. The study indicates that TD49 is an effective agent for the control for H. akashiwo and C. marina blooms in enclosed and eutrophic water bodies. 相似文献
992.
993.
Young Man Park Kazuya Matsumoto Yoo Jin Seo Min Jeung Kang Hidetoshi Nagashima 《Biological Rhythm Research》2013,44(1):39-51
The healthy 455 subjects above 60 years of age were questioned on their sleep habit inventory and the morningness-eveningness questionnaire. We analyzed the effects of age and sex on sleep habits and sleep-related trouble. Bedtimes on weekdays and weekends became earlier with aging, and women went to bed significantly later than men did. The length of sleep on weekdays slightly increased with aging, and it was longer for men than for women. The number of urinations and awakenings during nocturnal sleep and the amount of daytime napping increased with aging. The score on morningness-eveningness shifted toward the morning type with aging. In comparison with men, women had significantly longer sleep latency; and a higher percentage of subjects who reported that they sleep for only a short time, have sleep trouble, have received medical treatment for their sleep trouble, and take sleep medication. From these results, we deduced that the phase of sleep shifted forward in subjects above 60 years of age, and they showed frequent interruptions during nocturnal sleep and long daytime napping. We discussed the factor of gender difference in sleep in relation to social and cultural factors, particularly the household activities of women. 相似文献
994.
目的 分析重症加强病房(ICU)内侵袭性真菌感染的临床状况、病原菌菌群分布及耐药情况,为临床治疗及减少真菌感染提供参考依据.方法 回顾性分析3年来真菌培养阳性住院患者病例资料,从感染部位、菌种分布、真菌耐药情况等方面进行分析.结果 ICU中侵袭性真菌感染发生率为8.6%;尿液、痰液和血液分别为36.6%、28.8%和11.8%;真菌感染以假丝酵母菌为主要菌属(94.3%),白色假丝酵母菌占51.6%,是感染主要菌种;5种常见抗真菌药物敏感率最高的是两性霉素平均为99.8%,其次为伏立康唑;光滑念珠菌及热带念珠菌耐药比较严重,氟康唑(FLU)的敏感率分别为41.1%、17.6%,伊曲康唑的敏感性分别为6.1%、35.3%.结论 白色假丝酵母菌是ICU侵袭性真菌感染感染的主要病原菌;两性霉素及伏立康唑对5种念珠菌有较好的抗菌活性. 相似文献
995.
996.
997.
Adhesion molecules such as ICAM-1 are important in the infiltration of leukocytes into the site of inflammation. In this study, we investigated the inhibitory effects of curcumin on ICAM-1 expression and monocyte adhesiveness as well as its underlying action mechanism in the TNF-α-stimulated keratinocytes. Curcumin induced expression of heme oxygenase-1 (HO-1) in the human keratinocyte cell line HaCaT. In addition, curcumin induced Nrf2 activation in dose- and time-dependent manners in the HaCaT cells. Curcumin suppressed TNF-α- induced ICAM-1 expression and subsequent monocyte adhesion, which were reversed by the addition of tin protoporphyrin IX (SnPP), a specific inhibitor of HO-1, or HO-1 knockdown using siRNA. Furthermore, Nrf2 knockdown using siRNA reversed the inhibitory effect of curcumin on the TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that curcumin may exert its anti-inflammatory activity by suppressing the TNF-α-induced ICAM-1 expression and subsequent monocyte adhesion via expression of HO-1 in the keratinocytes. [BMB Reports 2013;46(8): 410-415] 相似文献
998.
Kyung-Won Hong Cheong-Sik Kim Haesook Min Seon-Joo Park Jae Kyung Park Younjhin Ahn Sung Soo Kim Yeonjung Kim 《Genes & genomics.》2013,35(1):69-75
Early menarche is associated with adverse health outcomes, including breast cancer, endometrial cancer, obesity, type 2 diabetes, and cardiovascular disease. Recently, a genomewide association study (GWAS) of age at menarche (AAM) in 104,533 individuals of European ancestry was reported by the ReproGen consortium. They identified 42 loci known and novel loci that were linked to age at menarche. Because age at menarche varies between ethnic groups, we decided to investigate if these results would be replicated in the Korean population. To this end, we examined the association of the SNPs reported in the ReproGen GWAS with AAM in 3,194 individuals from the Korean Genome and Epidemiology Study (KoGES) cohort. Genotype data for total 17 SNPs (6 genotyped SNPs and 11 imputed SNPs) were available for the association analysis using linear regression analysis for age at menarche with controlling current age, waist-to-hip ratio, and body mass index as the covariates. We found replication of the ReproGen study in two SNPs; one SNP (rs466639) in the retinoic acid receptor gamma gene (RXRG), showing a significant association with early menarche (beta = ?0.224 ± 0.065, p value = 5.2 × 10?4, Bonferroni-corrected p value = 0.009), and the other (rs10899489), in GRB2 (growth factor receptor bound protein 2)-associated binding protein 2 (GAB2), linked to late menarche (beta = 0.140 ± 0.047, p value = 2.8 × 10?3, Bonferroni-corrected p value = 0.049). This result possibly suggests that genetic factors governing AAM in the Korean population would be distinct from those in the Europeans, implying roles of modulating or interacting factors in determining AAM, including environmental factors such as nutritional status. 相似文献
999.
Although medicinal leeches have long been used as treatment for various ailments because of their potent anticoagulation factors, neither the full diversity of salivary components that inhibit coagulation, nor the evolutionary selection acting on them has been thoroughly investigated. Here, we constructed expressed sequence tag libraries from salivary glands of two species of medicinal hirudinoid leeches, Hirudo verbana and Aliolimnatis fenestrata, and identified anticoagulant‐orthologs through BLASTx searches. The data set then was augmented by the addition of a previously constructed EST library from the macrobdelloid leech Macrobdella decora. The identified orthologs then were compared and contrasted with well‐characterized anticoagulants from a variety of leeches with different feeding habits, including non‐sanguivorous species. Moreover, four different statistical methods for predicting signatures of positive and negative evolutionary pressures were used for 10 rounds each to assess the level and type of selection acting on the molecules as a whole and on specific sites. In total, sequences showing putative BLASTx‐orthology with five and three anticoagulant‐families were recovered in the A. fenestrata and H. verbana EST libraries respectively. Selection pressure analyses predicted high levels of purifying selection across the anticoagulant diversity, although a few isolated sites showed signatures of positive selection. This study represents a first attempt at mapping the anticoagulant repertoires in a comparative fashion across several leech families. 相似文献
1000.
Plant mating systems represent an evolutionary and ecological trade‐off between reproductive assurance through selfing and maximizing progeny fitness through outbreeding. However, many plants with sporophytic self‐incompatibility systems exhibit dominance interactions at the S‐locus that allow biparental inbreeding, thereby facilitating mating between individuals that share alleles at the S‐locus. We investigated this trade‐off by estimating mate availability and biparental inbreeding depression in wild radish from five different populations across Australia. We found dominance interactions among S‐alleles increased mate availability relative to estimates based on individuals that did not share S‐alleles. Twelve of the sixteen fitness variables were significantly reduced by inbreeding. For all the three life‐history phases evaluated, self‐fertilized offspring suffered a greater than 50% reduction in fitness, while full‐sib and half‐sib offspring suffered a less than 50% reduction in fitness. Theory indicates that fitness costs greater than 50% can result in an evolutionary trajectory toward a stable state of self‐incompatibility (SI). This study suggests that dominance interactions at the S‐locus provide a possible third stable state between SI and SC where biparental inbreeding increases mate availability with relatively minor fitness costs. This strategy allows weeds to establish in new environments while maintaining a functional SI system. 相似文献