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A series of color‐tunable Ca3–2x‐y‐zSiO4Cl2 (CSC):xCe3+,xLi+,yMn2+,zEu2+ phosphors with low temperature phase structure was synthesized via the sol–gel method. An energy transfer process from Ce3+ to Mn2+ in CSC:0.01Ce3+,0.01Li+,yMn2+ (y = 0.03–0.09) and the mechanism was verified to be an electric dipole–dipole interaction. The Ce3+ and Mn2+ emission intensities were greatly enhanced by co‐doping Eu2+ ions into CSC:0.01Ce3+,0.01Li+,0.07Mn2+ phosphors due to competitive energy transfers from Eu2+/Ce3+ to Mn2+, and Ce3+ to Eu2+. Under 332 nm excitation, CSC:0.01Ce3+,0.01Li+,0.07Mn2+,zEu2+ (z = 0.0005–0.002) exhibited tunable emission colors from green to white with coexisting orange, green and violet‐blue emissions. These phosphors could have potential application in white light‐emitting diodes.  相似文献   
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 Human prostate-specific antigen (PSA) has a highly restricted tissue distribution. Its expression is essentially limited to the epithelial cells of the prostate gland. Moreover, it continues to be synthesized by prostate carcinoma cells. This makes PSA an attractive candidate for use as a target antigen in the immunotherapy of prostate cancer. As a first step in characterizing the specific immune response to PSA and its potential use as a tumor-rejection antigen, we have incorporated PSA into a well-established mouse tumor model. Line 1, a mouse lung carcinoma, and P815, a mouse mastocytoma, have been transfected with the cDNA for human PSA. Immunization with a PSA-expressing tumor cell line demonstrated a memory response to PSA which protected against subsequent challenge with PSA-expressing, but not wild-type, tumors. Tumor-infiltrating lymphocytes could be isolated from PSA-expressing tumors grown in naive hosts and were specifically cytotoxic against a syngeneic cell line that expressed PSA. Immunization with tumor cells resulted in the generation of primary and memory cytotoxic T lymphocytes (CTL) specific for PSA. The isolation of PSA-specific CTL clones from immunized animals further demonstrated that PSA can serve as a target antigen for antitumor CTL. The immunogenicity studies carried out in this mouse tumor model provide a rationale for the design of methods to elicit PSA-specific cell-mediated immunity in humans. Received: 4 April 1996 / Accepted: 31 May 1996  相似文献   
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Here, we publish Lepisorus sect. Paragramma (Blume) C.F. Zhao, R. Wei & X.C. Zhang as a combinatio nova to replace the section name in Zhao et al. (2020), which was published as a status nova and turned out to be an invalid name, because we cited an incorrect basionym. A revised infrageneric classification of Lepisorus also is proposed.  相似文献   
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