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排序方式: 共有879条查询结果,搜索用时 31 毫秒
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Circulating hormones and estrous stage predict cellular and stromal remodeling in murine uterus 总被引:2,自引:0,他引:2
The understanding of how estrogen and progesterone (P(4)) drive uterine remodeling in rodents has largely been based on studies involving administration of exogenous hormones, using steroid receptor-deficient mice, or relying on vaginal smears. In all these cases, the actual serum levels of 17beta-estradiol (E(2)) and P(4) are not directly measured, and the relationship between physiological levels of female sex hormones and uterine remodeling in cycling mice has not been fully explored. Here, we measured the circulating levels of E(2) and P(4) in cycling mice and performed correlation analysis between hormone levels and epithelial and stromal uterine parameters, irrespective of the estrous stage. In parallel, these parameters were analyzed in relation to the more conventional method of vaginal smear classification of estrous stage. We found that circulating P(4) inversely correlated with uterine width, luminal epithelial proliferation, stromal apoptosis, and degradation of luminal epithelial basement membrane collagen type-IV. Circulating E(2) positively correlated with uterine width, stromal cell proliferation, and collagen type-I content, while it negatively correlated with glandular epithelial proliferation, loss of collagen type-IV surrounding glandular epithelium, and apoptosis in luminal, glandular, and stromal compartments. Our findings indicate that measuring P(4) or E(2) levels can predict many concurrent cellular and stromal events in the mouse uterus, suggesting that in naturally cycling mice cellular responses to hormone changes are not delayed, but occur very rapidly. 相似文献
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N‐Arylsulfonyl Indolines as Retinoic Acid Receptor‐Related Orphan Receptor γ (RORγ) Agonists 下载免费PDF全文
Dr. Christelle Doebelin Rémi Patouret Ruben D. Garcia‐Ordonez Dr. Mi Ra Chang Dr. Venkatasubramanian Dharmarajan Dana S. Kuruvilla Scott J. Novick Li Lin Dr. Michael D. Cameron Dr. Patrick R. Griffin Dr. Theodore M. Kamenecka 《ChemMedChem》2016,11(23):2607-2620
The nuclear retinoic acid receptor‐related orphan receptor γ (RORγ; NR1F3) is a key regulator of inflammatory gene programs involved in T helper 17 (TH17) cell proliferation. As such, synthetic small‐molecule repressors (inverse agonists) targeting RORγ have been extensively studied for their potential as therapeutic agents for various autoimmune diseases. Alternatively, enhancing TH17 cell proliferation through activation (agonism) of RORγ may boost an immune response, thereby offering a potentially new approach in cancer immunotherapy. Herein we describe the development of N‐arylsulfonyl indolines as RORγ agonists. Structure–activity studies reveal a critical linker region in these molecules as the major determinant for agonism. Hydrogen/deuterium exchange coupled to mass spectrometry (HDX‐MS) analysis of RORγ–ligand complexes help rationalize the observed results. 相似文献
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Ca2Gd8(SiO4)6O2 (CGS) nanophosphors with different concentrations of single-doped Dy3+ ions and co-doped Dy3+/Eu3+ ions were prepared by a solvothermal synthesis. Very fine particles in the nanometer range could be achieved by this method, as evidenced by transmission electron microscope measurements. The hexagonal phase of the oxyapatite structure was confirmed by X-ray diffraction patterns. The energy transfer between Eu3+ and Dy3+ ions was investigated by photoluminescence excitation and emission properties. These phosphors had absorption bands in the UV and NUV region, which are suitable for the emission wavelength of UV or NUV light-emitting diodes (LEDs). With increasing the Eu3+ ion concentration, the emission peak intensity corresponding to the 5D0→7F2 transition increased and the yellow (4F9/2→6H13/2) emission intensity also increased compared to the blue (4F9/2→6H15/2) emission intensity due to the increased energy transfer between Dy3+ to Eu3+ ions. Thus, the Eu3+ ions compensated the red emission component of the Dy3+ doped CGS nanophosphors. Such phosphors are expected to have potential applications for NUV based white LEDs. 相似文献
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Raj Kumar Singh Sunil Kumar Sinha A. Rama Rao 《Nuclear Engineering and Design》2009,239(10):1760-1767
The primary function of the shut down system in a nuclear reactor is to terminate any reactivity transient occurring in the core during its entire design life. Normally there is more than one system, which are independent and diverse in its mode of operation. They consist of quick acting mechanisms like dropping of safety rods by gravity, poison injection, etc. Typically in liquid poison injection system wherein high flow velocities are involved, there is significant fluid structure interaction associated with cyclic shock transients in the system. One such phenomenon has been captured and analyzed to understand the dynamics involved in the loop. The trends of loop pressure and vibration indicated presence of more than two pressure transients after complete injection of poison. The first transient arrived after 1.44 s and the second after 0.75 s. The reverse pressure pulses that manifested in the loop as a result of fast injection of fluid has been mathematically characterized by solving basic fluid balance equations. Possibility of ball lifting due to momentum pulse is also discussed. 相似文献
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A. Mohan BabuB.C. Jamalaiah J. Suresh KumarT. Sasikala L. Rama Moorthy 《Journal of Alloys and Compounds》2011,509(2):457-462
Lead tungsten tellurite (LTT) glasses doped with different Dy3+ ion concentrations have been prepared and characterized through optical absorption, photoluminescence and decay measurements. The glassy nature of the LTT host has been confirmed through the XRD measurements. The three phenomelogical intensity parameters Ωλ (λ = 2, 4, 6) have been determined from the absorption spectral intensities using the Judd-Ofelt (J-O) theory. The hypersensitivity of 6H15/2 → 6F11/2 transition based on the magnitude of Ω2 parameter has also been discussed. By using the J-O intensity parameters several radiative properties such as spontaneous transition probabilities (AR), fluorescence branching ratios (βR) and radiative lifetimes (τR) have been determined. The effect of Dy3+ ion concentration on the emission intensities of 4F9/2 → 6HJ′ (J′ = 15/2, 13/2, 11/2 and 9/2) transitions has also been reported. 相似文献
49.
Rama Subba Reddy Gorla 《Applied Thermal Engineering》2010,30(17-18):2763-2769
Liquefied Natural Gas transport and storage has become very important due to its ability to occupy 1/600th of the volume that compressed natural gas would occupy at room temperature and atmospheric pressure. In the present work, an LNG storage tank has been computationally simulated and probabilistically evaluated in view of the several uncertainties in the fluid, structural, material and thermal variables that govern the LNG storage tank. A finite element code ALGOR was used to couple the thermal profiles with structural design. The stresses and their variations were evaluated at critical points on the storage tank. Cumulative distribution functions and sensitivity factors were computed for stress responses due to fluid, mechanical and thermal random variables. These results can be used to quickly identify the most critical design variables in order to optimize the design and make it cost effective. The total heat gained by the liquid part in the tank has been evaluated and the amount of boil-off was calculated. Various methods have been proposed to minimize thermal stresses. 相似文献
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