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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
Jorge Lopez-Tello Maria Angeles Jimenez-Martinez Esteban Salazar-Petres Ritik Patel Amy L. George Richard G. Kay Amanda N. Sferruzzi-Perri 《International journal of molecular sciences》2022,23(11)
Pregnancy is characterized by adaptations in the function of several maternal body systems that ensure the development of the fetus whilst maintaining health of the mother. The renal system is responsible for water and electrolyte balance, as well as waste removal. Thus, it is imperative that structural and functional changes occur in the kidney during pregnancy. However, our knowledge of the precise morphological and molecular mechanisms occurring in the kidney during pregnancy is still very limited. Here, we investigated the changes occurring in the mouse kidney during pregnancy by performing an integrated analysis involving histology, gene and protein expression assays, mass spectrometry profiling and bioinformatics. Data from non-pregnant and pregnant mice were used to identify critical signalling pathways mediating changes in the maternal kidneys. We observed an expansion of renal medulla due to proliferation and infiltration of interstitial cellular constituents, as well as alterations in the activity of key cellular signalling pathways (e.g., AKT, AMPK and MAPKs) and genes involved in cell growth/metabolism (e.g., Cdc6, Foxm1 and Rb1) in the kidneys during pregnancy. We also generated plasma and urine proteomic profiles, identifying unique proteins in pregnancy. These proteins could be used to monitor and study potential mechanisms of renal adaptations during pregnancy and disease. 相似文献
912.
Chinmay Vijay Tikhe Victor Cardoso-Jaime Shengzhang Dong Natalie Rutkowski George Dimopoulos 《International journal of molecular sciences》2022,23(14)
Cysteine-rich trypsin inhibitor-like domain (TIL)-harboring proteins are broadly distributed in nature but remain understudied in vector mosquitoes. Here we have explored the biology of a TIL domain-containing protein of the arbovirus vector Aedes aegypti, cysteine-rich venom protein 379 (CRVP379). CRVP379 was previously shown to be essential for dengue virus infection in Ae. aegypti mosquitoes. Gene expression analysis showed CRVP379 to be highly expressed in pupal stages, male testes, and female ovaries. CRVP379 expression is also increased in the ovaries at 48 h post-blood feeding. We used CRISPR-Cas9 genome editing to generate two mutant lines of CRVP379 with mutations inside or outside the TIL domain. Female mosquitoes from both mutant lines showed severe defects in their reproductive capability; mutant females also showed differences in their follicular cell morphology. However, the CRVP379 line with a mutation outside the TIL domain did not affect male reproductive performance, suggesting that some CRVP379 residues may have sexually dimorphic functions. In contrast to previous reports, we did not observe a noticeable difference in dengue virus infection between the wild-type and any of the mutant lines. The importance of CRVP379 in Ae. aegypti reproductive biology makes it an interesting candidate for the development of Ae. aegypti population control methods. 相似文献
913.
Abstract In this study, a layered cuttings transport model is developed for high-angle and horizontal wells, which can be used for incompressible non-Newtonian fluids as well as compressible non-Newtonian fluids (i.e., foams). The effects of major drilling parameters, such as flow rate, rate of penetration, fluid density, viscosity, gas ratio, cuttings size, cuttings density, wellbore inclination and eccentricity of the drillsting on cuttings transport efficiency are analyzed. The major findings from this study are, the dominating parameter on wellbore cleaning is the flow rate, and, as the viscosity of the fluid is increased, the thickness of the cuttings bed developed in the wellbore is significantly increasing. Also, cuttings properties, fluid density, wellbore inclination and eccentricity have some influence on cuttings transport. 相似文献
914.
915.
Impulse noise detection and removal using fuzzy techniques 总被引:19,自引:0,他引:19
A new algorithm is presented which can remove impulse noise from corrupted images while preserving details. The algorithm is based on fuzzy impulse detection and fuzzy noise cancellation techniques. Experimental results show that the algorithm is capable of providing significant improvement over many published techniques in terms of both subjective and objective evaluations 相似文献
916.
This paper presents a new zero-voltage-switching (ZVS) bidirectional dc-dc converter. Compared to the traditional full and half bridge bidirectional dc-dc converters for the similar applications, the new topology has the advantages of simple circuit topology with no total device rating (TDR) penalty, soft-switching implementation without additional devices, high efficiency and simple control. These advantages make the new converter promising for medium and high power applications especially for auxiliary power supply in fuel cell vehicles and power generation where the high power density, low cost, lightweight and high reliability power converters are required. The operating principle, theoretical analysis, and design guidelines are provided in this paper. The simulation and the experimental verifications are also presented. 相似文献
917.
Daniel Octavian Costache Oana Feroiu Adelina Ghilencea Mihaela Georgescu Ana Cruntu Constantin Cruntu Sorin George
iplica Mariana Jinga Raluca Simona Costache 《International journal of molecular sciences》2022,23(9)
The systemic inflammatory syndrome concept is one of the foundations that stand at the basis of revolutionary modern and future therapies, based on the in-depth understanding of the delicate mechanisms that govern the collaboration between the systems and organs of the human body and, at the same time, the fine balance that ensures a reproach-free operation. An interesting concept that we propose is that of the environment-inadequacy status, a concept that non-specifically incorporates all the situations of the organism’s response disorders in the face of imprecisely defined situations of the environment. The correlation between these two concepts will define the future of modern medicine, along with the gene-adjustment mechanisms. Psoriasis is a clear example of an inadequate body response as a result of exposure to as of yet undefined triggers with an excessive systemic inflammatory reaction and hitherto insufficiently controllable. Modern biological therapies, such as TNF-α, IL-12 family, and IL-17 inhibitors, are intended to profoundly reshape the cytokine configuration of patients with inflammatory diseases such as psoriasis, with tremendous success in disease control. Yet, because of the important roles of cytokines in cancer promotion and control, concern was raised about the fact that the use of biologicals may alter immune surveillance and promote cancer progression. Both theoretical and practical data nevertheless showed that the treatment-induced control of cytokines may be beneficial for reducing the inflammatory milieu that promotes cancer and such have a beneficial role in maintaining health. We briefly present the intricate roles of those cytokine families on cancer control, with some debates on if their inhibition might or might not promote additional tumoral development. 相似文献
918.
Decarbonylation of formic acid in 46.6–80.2% (6.5–14.1 m) sulphuric acid was studied by driving CO out of the reaction medium by an air current followed by its photometrical determination with Ag-Na-sulphamoyl-benzoate. The logarithm of the reaction rate constant increases straight with the acidity of the medium in the 6.5–12.6 M H2SO4 range. The data obtained argue in favour of a possible implication of a sulphuric acid molecule respectively hydrogensulphate ion in a rate controlling step. 相似文献
919.
920.