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1.
Changes in the protein and steroid hormones of follicular fluid, aspirated from different follicles of sheep and human ovaries, have been measured and correlated with the size of the follicles. As the fluid contains a number of proteins, steroids have been measured directly and after ether extraction. The follicular fluid concentrations of progesterone and 17 beta-oestradiol measured directly in the fluid increased with the size of the follicles. The levels of free testosterone remained constant in all sizes of follicles, while those of bound hormone showed a 10- to 15-fold increase over the free testosterone concentrations in both the sheep and human follicular fluid. A decrease in the levels of bound testosterone in the fluid of large follicles (LFFL) coincided with the increase in bound 17 beta-oestradiol, suggesting the possible conversion of bound testosterone to oestrogen as the follicle attained maturity. The ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) varied in the fluid obtained from different size follicles, being 1:7 in small (SFFL), 1.3.5 in medium (MFFL) and 1:2.3 in large (LFFL) follicles of sheep ovaries. The LH content of follicular fluid of different size follicles appeared to be the same, with LFFL showing a minor increase over SFFL. In the human, the fluid from medium follicles contained very little LH compared to LFFL. These differences in the pattern of LH levels present in the fluid from different size follicles between human and sheep ovaries presumably reflect species variations in the entry of LH into the follicles. 相似文献
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Kshirsagar Parthraj R. Mohite Ashwini Suryawanshi Suresh Chavan Jaykumar J. Gaikwad Nikhil B. Bapat Vishwas A. 《Plant Cell, Tissue and Organ Culture》2021,144(2):383-396
Plant Cell, Tissue and Organ Culture (PCTOC) - The present study reports an optimized protocol for high frequency in vitro plant propagation through direct and indirect organogenesis, phytochemical... 相似文献
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Dynlacht JR Valluri S Garrett J Mendonca MS Lopez JT Caperell-Grant A Bigsby RM 《Radiation research》2011,175(1):37-43
Astronauts participating in extended lunar missions or the projected mission to Mars would likely be exposed to significant doses of high-linear energy transfer (LET) heavy energetic charged (HZE) particles. Exposure to even relatively low doses of such space radiation may result in a reduced latent period for and an increased incidence of lens opacification. However, the determinants of cataractogenesis induced by densely ionizing radiation have not been clearly elucidated. In the current study, we show that age at the time of exposure is a key determinant of cataractogenesis in rats whose eyes have been exposed to 2 Gy of (56)Fe ions. The rate of progression of cataractogenesis was significantly greater in the irradiated eyes of 1-year-old rats compared to young (56-day-old) rats. Furthermore, older ovariectomized rats that received exogenous estrogen treatment (17-β-estradiol) commencing 1 week prior to irradiation and continuing throughout the period of observation of up to approximately 600 days after irradiation showed an increased incidence of cataracts and faster progression of opacification compared to intact rats with endogenous estrogen or ovariectomized rats. The same potentiating effect (higher incidence, reduced latent period) was observed for irradiated eyes of young rats. Modulation of estrogen status in the 1-year-old animals (e.g., removal of estrogen by ovariectomy or continuous exposure to estrogen) did not increase the latent period or reduce the incidence to that of intact 56-day-old rats. Since the rapid onset and progression of cataracts in 1-year-old compared to 56-day-old rats was independent of estrogen status, we conclude that estrogen cannot account for the age-dependent differences in cataractogenesis induced by high-LET radiation. 相似文献
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The cancer stem cell (CSC) theory predicts that a small fraction of cancer cells possess unique self-renewal activity and mediate tumor initiation and propagation. However, the molecular mechanisms involved in CSC regulation remains unclear, impinging on effective targeting of CSCs in cancer therapy. Here we have investigated the hypothesis that Rac1, a Rho GTPase implicated in cancer cell proliferation and invasion, is critical for tumor initiation and metastasis of human non-small cell lung adenocarcinoma (NSCLA). Rac1 knockdown by shRNA suppressed the tumorigenic activities of human NSCLA cell lines and primary patient NSCLA specimens, including effects on invasion, proliferation, anchorage-independent growth, sphere formation and lung colonization. Isolated side population (SP) cells representing putative CSCs from human NSCLA cells contained elevated levels of Rac1-GTP, enhanced in vitro migration, invasion, increased in vivo tumor initiating and lung colonizing activities in xenografted mice. However, CSC activity was also detected within the non-SP population, suggesting the importance of therapeutic targeting of all cells within a tumor. Further, pharmacological or shRNA targeting of Rac1 inhibited the tumorigenic activities of both SP and non-SP NSCLA cells. These studies indicate that Rac1 represents a useful target in NSCLA, and its blockade may have therapeutic value in suppressing CSC proliferation and metastasis. 相似文献
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James F. Sampson Eiichi Hasegawa Lama Mulki Amol Suryawanshi Shuhong Jiang Wei-Sheng Chen Gabriel A. Rabinovich Kip M. Connor Noorjahan Panjwani 《PloS one》2015,10(6)
Galectins have emerged as potent immunoregulatory agents that control chronic inflammation through distinct mechanisms. Here, we report that treatment with Galectin-8 (Gal-8), a tandem-repeat member of the galectin family, reduces retinal pathology and prevents photoreceptor cell damage in a murine model of experimental autoimmune uveitis. Gal-8 treatment increased the number of regulatory T cells (Treg) in both the draining lymph node (dLN) and the inflamed retina. Moreover, a greater percentage of Treg cells in the dLN and retina of Gal-8 treated animals expressed the inhibitory coreceptor cytotoxic T lymphocyte antigen (CTLA)-4, the immunosuppressive cytokine IL-10, and the tissue-homing integrin CD103. Treg cells in the retina of Gal-8-treated mice were primarily inducible Treg cells that lack the expression of neuropilin-1. In addition, Gal-8 treatment blunted production of inflammatory cytokines by retinal T helper type (TH) 1 and TH17 cells. The effect of Gal-8 on T cell differentiation and/or function was specific for tissues undergoing an active immune response, as Gal-8 treatment had no effect on T cell populations in the spleen. Given the need for rational therapies for managing human uveitis, Gal-8 emerges as an attractive therapeutic candidate not only for treating retinal autoimmune diseases, but also for other TH1- and TH17-mediated inflammatory disorders. 相似文献
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