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861.
Cytostatic and growth-stimulating effects of alveolar macrophages (AM) of rats on tumor cells were studied. The experimental results are summarized as follows. 1. The cytotoxicity of AM activated with BCG to tumor cells was increasing with the increase of effector cells/target cells (E/T) ratio. AM without the treatment with BCG expressed slight cytotoxicity to tumor cells at a high E/T, and growth-stimulating effect on tumor cells, at a low E/T. 2. AM after 24-hour culture had a lower manifestation of cytotoxicity to human lung adenocarcinoma cell line than that of AM without 24-hour culture, and had a growth-stimulating effect on B-16 cell line. 3. Cytostatic and growth-stimulating effects of AM without or with 24-hour culture were decreasing with the increase of irradiation doses. 相似文献
862.
863.
864.
Pereira LM Hatanaka E Martins EF Oliveira F Liberti EA Farsky SH Curi R Pithon-Curi TC 《Cell biochemistry and function》2008,26(2):197-204
Inflammation is a crucial step for the wound healing process. The effect of linoleic and oleic acids on the inflammatory response of the skin during the healing process and on the release of pro-inflammatory cytokines by rat neutrophils in vitro was investigated. A wound in the dorsal surface of adult rats was performed and fatty acids were then topically administered. Both oleic and linoleic acids increased the wound healing tissue mass. The total protein and DNA contents of the wounds were increased by the treatment with linoleic acid. The treatments with oleic and linoleic acids did not affect vascular permeability. However, the number of neutrophils in the wounded area and air pouches was increased and the thickness of the necrotic cell layer edge around the wound was decreased. A dose-dependent increase in vascular endothelial growth factor-alpha (VEGF-alpha) and interleukin-1beta (IL-1beta) by neutrophils incubated in the presence of oleic and linoleic acid was observed. Oleic acid was able to stimulate also the production of cytokine-induced neutrophil chemoattractant in inflammation 2 alpha/beta (CINC-2alpha/beta). This pro-inflammatory effect of oleic and linoleic acids may speed up the wound healing process. 相似文献
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866.
Long-Range Correlations of Global Sea Surface Temperature 总被引:1,自引:0,他引:1
Scaling behaviors of the global monthly sea surface temperature (SST) derived from 1870–2009 average monthly data sets of Hadley Centre Sea Ice and SST (HadISST) are investigated employing detrended fluctuation analysis (DFA). The global SST fluctuations are found to be strong positively long-range correlated at all pertinent time-intervals. The value of scaling exponent is larger in the tropics than those in the intermediate latitudes of the northern and southern hemispheres. DFA leads to the scaling exponent α = 0.87 over the globe (60°S~60°N), northern hemisphere (0°N~60°N), and southern hemisphere (0°S~60°S), α = 0.84 over the intermediate latitude of southern hemisphere (30°S~60°S), α = 0.81 over the intermediate latitude of northern hemisphere (30°N~60°N) and α = 0.90 over the tropics 30°S~30°N [fluctuation F(s) ~ sα], which the fluctuations of monthly SST anomaly display long-term correlated behaviors. Furthermore, the larger the standard deviation is, the smaller long-range correlations (LRCs) of SST in the corresponding regions, especially in three distinct upwelling areas. After the standard deviation is taken into account, an index χ = α * σ is introduced to obtain the spatial distributions of χ. There exists an obvious change of global SST in central east and northern Pacific and the northwest Atlantic. This may be as a clue on predictability of climate and ocean variabilities. 相似文献
867.
Yali Hou Yachun Wang Xuemei Lu Xu Zhang Qian Zhao Rory J. Todhunter Zhiwu Zhang 《PloS one》2013,8(10)
Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone. 相似文献
868.
Hui Zhu Yugui Cui Jin Xie Ling Chen Xiangxiang Chen Xuejiang Guo Yefei Zhu Xinghai Wang Jiansun Tong Zuomin Zhou Yue Jia Yan‐he Lue Amiya Sinha Hikim Christina Wang Ronald S. Swerdloff Jiahao Sha 《Proteomics》2010,10(19):3480-3493
Mild testicular heating safely and reversibly suppresses spermatogenesis. In this study, we attempted to clarify the underlying molecular mechanism(s) involved in heat‐induced spermatogenesis suppression in human testis. We conducted global proteomic analyses of human testicular biopsies before, and at 2 and 9 wk after heat treatment. Thirty‐one and Twenty‐six known proteins were identified with significant differential expression at 2 and 9 wk after heat treatment, respectively. These were used to characterize the cellular and molecular events in the testes when seminiferous epithelia became damaged (2 wk) and recovered (9 wk). At 2 wk post‐treatment, the changed expression of a series of proteins could promote apoptosis or suppress proliferation and cell survival. At 9 wk post‐treatment, the changed expression of proteins mainly promoted cell proliferation, differentiation and survival, but resisted cell apoptosis. Among those heat‐regulated proteins, HNRNPH1 was selected for the further functional study. We found that HNRNPH1 was an anti‐apoptosis protein that could regulate the expression of other heat‐induced proteins. In conclusion, heat‐induced reversible suppression of spermatogenesis occurred by modulating the expression of proteins related to proliferation, differentiation, apoptosis and cell survival pathways. These differentially expressed proteins were found to be key molecular targets affecting spermatogenesis after heat treatment. 相似文献
869.
870.