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This paper reviews the state-of-the-art technologies, characterizations, materials (precursors and encapsulants), and challenges concerning multicolor and white light-emitting diodes (LEDs) based on carbon dots (CDs) as color converters. Herein, CDs are exploited to achieve emission in LEDs at wavelengths longer than the pump wavelength. White LEDs are typically obtained by pumping broad band visible-emitting CDs by an UV LED, or yellow–green-emitting CDs by a blue LED. The most important methods used to produce CDs, top-down and bottom-up, are described in detail, together with the process that allows one to embed the synthetized CDs on the surface of the pumping LEDs. Experimental results show that CDs are very promising ecofriendly candidates with the potential to replace phosphors in traditional color conversion LEDs. The future for these devices is bright, but several goals must still be achieved to reach full maturity.  相似文献   
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In the 50 years since the first edition of this journal, operative paediatric surgery has undergone radical change. Many of the most common instruments are unchanged, both as a testament to their utility and in recognition of past surgeons remembered eponymously. Surrounding that basic core of instruments, theatre has changed radically as new tools and techniques have arisen. Surgeons have come down from their pedestals, recognising surgery as a team sport rather than a solo performance. More than half of the current paediatric surgical trainees are women, a higher proportion than in any other craft group of the Royal Australasian College of Surgeons. The appearance, and rapid development, of laparoscopy is to many observers the most notable change in surgery over the last 50 years. Placed in its context though, it is simply the most prominent example of a frameshift in surgical thinking. The patient as a whole is now the focus, rather than just the disease. Recent developments are as much about minimising harm to normal tissues as they are about extirpating pathology. As a surgical maxim, ‘Primum non nocere’ is even more in evidence in 2015 than it was in 1965.  相似文献   
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A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
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目的:探讨输尿管硬镜在尿路疾病治疗中的应用效果。方法:对1000例尿路结石、输尿管及尿道狭窄、输尿管息肉、梗阻、异物存留等患者,均以输尿管硬镜配合其他设备进行治疗。结果:肾内结石34例治愈率76.5%,输尿管结石、膀胱及尿道结石治愈率为94.5%~99.8%;泌尿道狭窄治愈率66.7%~75%;33例泌尿道异物取出率97%。结论:基层医院在尿路疾病治疗中,根据病变的不同部位,将输尿管硬镜灵活配合现有并不高档的设备,同样可以取得较好的微创手术效果。  相似文献   
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We have previously reported that ICOS‐Ig expressed locally by a PIEC xenograft induces a perigraft cellular accumulation of CD4+CD25+Foxp3+ T cells and specific xenograft prolongation. In the present study we isolated and purified CD4+CD25+ T cells from ICOS‐Ig secreting PIEC grafts to examine their phenotype and mechanism of xenograft survival using knockout and mutant mice. CD4+CD25+ T cells isolated from xenografts secreting ICOS‐Ig were analysed by flow cytometry and gene expression by real‐time PCR. Regulatory function was examined by suppression of xenogeneic or allogeneic primed CD4 T cells in vivo. Graft prolongation was shown to be dependent on a pre‐existing Foxp3+ Treg, IL‐10, perforin and granzyme B. CD4+CD25+Foxp3+ T cells isolated from xenografts secreting ICOS‐Ig demonstrated a phenotype consistent with nTreg but with a higher expression of CD275 (ICOSL), expression of CD278 (ICOS) and MHC II and loss of CD73. Moreover, these cells were functional and specifically suppressed xenogeinic but not allogeneic primed T cells in vivo.  相似文献   
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BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
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