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71.
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Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM‐induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM‐induced expression of α‐smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor‐β1, interleukin‐1β, and tumor necrosis factor‐α in the lungs of BLM‐stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM‐induced murine model.  相似文献   
73.
A major challenge in understanding the response of populations to climate change is to separate the effects of local drivers acting independently on specific populations, from the effects of global drivers that impact multiple populations simultaneously and thereby synchronize their dynamics. We investigated the environmental drivers and the demographic mechanisms of the widespread decline in marine survival rates of Atlantic salmon (Salmo salar) over the last four decades. We developed a hierarchical Bayesian life cycle model to quantify the spatial synchrony in the marine survival of 13 large groups of populations (called stock units, SU) from two continental stock groups (CSG) in North America (NA) and Southern Europe (SE) over the period 1971–2014. We found strong coherence in the temporal variation in postsmolt marine survival among the 13 SU of NA and SE. A common North Atlantic trend explains 37% of the temporal variability of the survivals for the 13 SU and declines by a factor of 1.8 over the 1971–2014 time series. Synchrony in survival trends is stronger between SU within each CSG. The common trends at the scale of NA and SE capture 60% and 42% of the total variance of temporal variations, respectively. Temporal variations of the postsmolt survival are best explained by the temporal variations of sea surface temperature (SST, negative correlation) and net primary production indices (PP, positive correlation) encountered by salmon in common domains during their marine migration. Specifically, in the Labrador Sea/Grand Banks for populations from NA, 26% and 24% of variance is captured by SST and PP, respectively and in the Norwegian Sea for populations from SE, 21% and 12% of variance is captured by SST and PP, respectively. The findings support the hypothesis of a response of salmon populations to large climate‐induced changes in the North Atlantic simultaneously impacting populations from distant continental habitats.  相似文献   
74.
Transfersomes were a special kind of nanomaterials with higher deformability and flexibility. A rapid method for coated-column preparation using anionic transfersomes as a coating material by electrostatic adsorption was developed. With carboxymethyl-β-cyclodextrin added in running buffer as the chiral selector, the capillary electrochromatography enantioseparation system based on the transfersomes-coated column modified by electrostatic adsorption was established for the first time. Propranolol and metoprolol acted as model drugs to evaluate the enantioseparation performance, these two basic drugs achieved baseline separation with satisfactory resolution and selection factor in this transfersomes-electrochromatography system but only partial separation in bare column system. In order to get the optimal separation condition, concentration of chiral selector, buffer pH, and applied voltage were systematically investigated. A rapid and efficient enantioseparation electrochromatography system was established and showed that transfersomes as the stationary phase could efficiently improve chiral separation effect.  相似文献   
75.
Incorporating male sterility into hybrid seed production reduces its cost and ensures high varietal purity. Despite these advantages, male‐sterile lines have not been widely used to produce tomato (Solanum lycopersicum) hybrid seeds. We describe the development of a biotechnology‐based breeding platform that utilized genic male sterility to produce hybrid seeds. In this platform, we generated a novel male‐sterile tomato line by clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR‐associated protein 9 (Cas9)‐mediated mutagenesis of a stamen‐specific gene SlSTR1 and devised a transgenic maintainer by transforming male‐sterile plants with a fertility‐restoration gene linked to a seedling‐colour gene. Offspring of crosses between a hemizygous maintainer and the homozygous male‐sterile plant segregated into 50% non‐transgenic male‐sterile plants and 50% male‐fertile maintainer plants, which could be easily distinguished by seedling colour. This system has great practical potential for hybrid seed breeding and production as it overcomes the problems intrinsic to other male‐sterility systems and can be easily adapted for a range of tomato cultivars and diverse vegetable crops.  相似文献   
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The present study reports the length-weight relationships (LWRs) for eight fish species sampled in Hailang River, a left-bank tributary of the Mudan River in Northeast China. The fishes were collected from April to October bimonthly 2017 by electrofishing (fishing 2 kilometers along the river and within 5 meters from the bank) and netting (drift gillnet: mesh size 2 cm × 3 cm; 200 m net length). The specimens were weighed (nearest 0.1 g) and measured (nearest 0.1 cm) in the laboratory. This study provides an update in maximum lengths for five species.  相似文献   
79.
Sheng  Yumeng  Cao  Manlin  Liu  Yiwen  He  Yiqing  Zhang  Guoliang  Du  Yan  Gao  Feng  Yang  Cuixia 《Molecular and cellular biochemistry》2021,476(9):3383-3391
Molecular and Cellular Biochemistry - Although luminal breast cancer cells are typically highly cohesive epithelial cells and have low invasive ability, many eventually develop metastasis. Until...  相似文献   
80.
Yu  Du  Zhao  Yundi  Pan  Junhui  Yang  Xingmiao  Liang  Zhenjie  Xie  Shengda  Cao  Ruibing 《中国病毒学》2021,36(6):1443-1455
Virologica Sinica - The Japanese encephalitis serogroup of the neurogenic Flavivirus has a specific feature that expresses a non-structural protein NS1′ produced through a programmed -1...  相似文献   
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