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81.
In this paper, CdMnTe nanopowders with uniform shapes were prepared through a facile hydrothermal route using 3-mercaptopropionic acid (MPA) as the stabilizer and modifier. The effects of different experimental conditions including Cd-to-MPA ratio, pH value and reaction temperature on the phase composition and formation mechanism of as-prepared nanopowders were studied. XRD results indicated as-prepared CdMnTe nanopowders were pure phase and had cubic sphalerite structure with high crystallinity. SEM and Rietveld refinement clearly showed that the powders were about 10–100 nm in size. In PL measurement, there was a strong luminescence peak in the infrared region 1.717–1.826 eV. Compared with the CdMnTe single crystal, a blue shift of about 0.109 eV indicated a wider band gap. In UV-vis spectra, the absorption peak of the sample blue shifted with the decrease of crystal size, which indicated an obvious quantum confinement effect (QCE) in nanopowders. The optimal conditions for the preparation of CdMnTe nanopowders are 180 °C for 24 h with the molar ratio 1 : 1 of Cd : MPA at pH 13. In particular, the growth kinetics and possible formation mechanism of the nanopowders were proposed.

CdMnTe high-quality and pure phase nanopowders, with diameters of 20 nm to 100 nm, were synthesized by a hydrothermal route using mercapto propionic acid as the stabilizer. A CdMnTe single crystal was produced by melting method and flash sintering using CdMnTe nanopowder.  相似文献   
82.
We evaluated whether demographics and COVID-19 symptoms predicted COVID-19 deaths among healthcare workers (HCWs) in the United States by comparing COVID-19 deaths in HCWs with 3 control groups (HCW nondeaths, non-HCW deaths, and non-HCW nondeaths) using a case–control design. We obtained patient-level data of 33 variables reported during January 1, 2020–October 12, 2021, in all US states. We used logistic regression analysis while controlling for confounders. We found that persons who were >50 years of age, male, Black, or Asian experienced significantly more deaths than matched controls. In addition, HCWs who died had higher risks for the most severe clinical indicators. We also found that the most indicative symptoms were preexisting medical conditions, shortness of breath, fever, cough, and gastrointestinal symptoms. In summary, minority, male, and older HCWs had greater risk for COVID-19 death. Severe clinical indicators and specific symptoms may predict COVID-19–related deaths among HCWs.  相似文献   
83.
Objective Racial and ethnic health disparities affect the diagnosis and management of melanoma and nonmelanoma skin cancers, leading to deleterious outcomes. Non-Hispanic White patients make up the majority of skin cancers cases, yet racial and ethnic minorities have poorer prognoses and outcomes. The skin cancer literature is fragmented with regards to potential contributors to these healthcare disparities. In this article, we provide a comprehensive review of the skin cancer literature to briefly quantify racial and ethnic inequities, highlight contributing factors, and propose practical changes that can be made.MethodsA PubMed search was completed to identify articles related to racial and ethnic health care disparities in the context of melanoma, basal cell carcinoma, squamous cell carcinoma, Merkel cell carcinoma, and dermatofibrosarcoma protuberans.ResultsRelative to non-Hispanic White patients, patients of racial and ethnic minorities have differing clinical presentations of skin cancers and genetic risk factors. Insurance, access to specialty care, cultural beliefs, and available educational resources further contribute to racial and ethnic disparities.LimitationsWe are limited to the level of detail provided in the existing literature, and at some times are unable to distinguish race of Hispanic populations. We also acknowledge that there are different nationalities grouped under these broad labels as well as multi-racial populations that may not be accounted for.ConclusionAwareness of and familiarization with innate factors and potentially more modifiable contributors can help inform efforts to close the observed gap in racial and ethnic inequities.  相似文献   
84.
Purpose : To investigate the signal factor and its function in the medium-mediated bystander effect during heavy-ion irradiation of human salivary gland (HSG) neoplastic cells. Materials and methods : Unirradiated recipient HSG cells were co-cultivated with HSG donor cells irradiated with 290 MeV/u carbon beams having different LET values. Cell proliferation and micronucleus (MN) induction in recipient cells with and without treatment of a NO scavenger (PTIO) were measured and the concentration of nitrite in the co-culture medium was detected. As a direct control, the effects of a nitric oxide (NO) generator (sper/NO) on cell proliferation and MN induction were also examined. Results : Increases in cell proliferation and MN induction were found in the recipient HSG cells as a result of co-culturing and cell proliferation was obviously enhanced during a further subculture. In comparison with 13 keV/ μ m, 100 keV/ μ m carbon-ion irradiation was found to be a more efficient inducer of the medium-mediated bystander effect. The treatment of cells by PTIO resulted in elimination of such effects, which supports a role for NO in the medium-mediated bystander effect. As an oxidization product of NO, nitrite was detected in the co-culture medium, and the dose-response for its concentration was similar to that of cell proliferation and MN induction in the recipient cells. When the HSG cells were treated by sper/NO with a concentration of less than 20 μ M, cell proliferation was enhanced, whereas MN increased along with sper/NO concentration. Conclusion : NO participated in the medium-mediated bystander effects on cell proliferation and MN induction, depending on the LET of irradiation.  相似文献   
85.
INTRODUCTION Siglec-15 is a member of the sialic acid-binding immunoglobulintype lectin (Siglecs) family, a group of cell-surface receptors that potentially reg...  相似文献   
86.
Prostate cancer (PCa) incidence and mortality rate vary among racial and ethnic groups with the highest occurrence in African American (AA) men who have mortality rates twice that of Caucasians (CA). In this study, we focused on differential expression of proteins in AA prostate cancer compared to CA using Protein Pathway Array Analysis (PPAA), in order to identify protein biomarkers associated with PCa racial disparity. Fresh frozen prostate samples (n=90) obtained from radical prostatectomy specimens with PCa, including 25 AA tumor, 21 AA benign, 23 CA tumor, 21 CA benign samples were analyzed. A total of 286 proteins and phosphoproteins were assessed using PPAA. By PPAA analysis, 33 proteins were found to be significantly differentially expressed in tumor tissue (n=48, including both CA and AA) in comparison to benign tissue (n=42). We further compared protein expression levels between AA and CA tumor groups and found that 3 proteins were differentially expressed (P<0.05 and q<5%). Aurora was found to be significantly increased in AA tumors, while Cyclin D1 and HNF-3a proteins were downregulated in AA tumors. Predicted risk score was significantly different between AA and CA ethnic groups using logistic regression analysis. In conclusion, we identified Aurora, Cyclin D1 and HNF-3a proteins as being differentially expressed between AA and CA in PCa tissue. Our study suggests that these proteins might be involved in different pathways that lead to aggressive PCa behavior in AA patients, potentially serving as biomarkers for the PCa racial disparity.  相似文献   
87.
对37例经开腹手术和病理结果证实为卵巢巧克力囊肿破裂的病例进行分析。本病发病呈上升趋势,误诊率高,本文结果显示术前确诊16例,确诊率为43.2%,本病特点为月经期或月经周期后半期发生突发性下腹剧痛伴明显腹膜刺激症,后穹隆穿刺抽出咖啡色液体,且无闭经,阴道不规则出血及休克体征。21例分别误诊为卵巢囊肿蒂扭转,黄体破裂,异位妊娠和急性阑尾炎,其中阑尾炎占8例,提示本症需与上述妇科急腹症和急性阑尾炎鉴别  相似文献   
88.
Proliferation of latently infected CD4+ T cells with replication-competent proviruses is an important mechanism contributing to HIV persistence during antiretroviral therapy (ART). One approach to targeting this latent cell expansion is to inhibit mTOR, a regulatory kinase involved with cell growth, metabolism, and proliferation. Here, we determined the effects of chronic mTOR inhibition with rapamycin with or without T cell activation in SIV-infected rhesus macaques (RMs) on ART. Rapamycin perturbed the expression of multiple genes and signaling pathways important for cellular proliferation and substantially decreased the frequency of proliferating CD4+ memory T cells (TM cells) in blood and tissues. However, levels of cell-associated SIV DNA and SIV RNA were not markedly different between rapamycin-treated RMs and controls during ART. T cell activation with an anti-CD3LALA antibody induced increases in SIV RNA in plasma of RMs on rapamycin, consistent with SIV production. However, upon ART cessation, both rapamycin and CD3LALA–treated and control-treated RMs rebounded in less than 12 days, with no difference in the time to viral rebound or post-ART viral load set points. These results indicate that, while rapamycin can decrease the proliferation of CD4+ TM cells, chronic mTOR inhibition alone or in combination with T cell activation was not sufficient to disrupt the stability of the SIV reservoir.  相似文献   
89.
目的:探讨青龙藤提取物(BH)降低糖尿病模型大鼠的血糖作用。方法:将32只雄性Wistar大鼠随机均分成4组,正常对照组,其他3组以链脲佐菌素(STZ)制成接近于人1型糖尿病的大鼠糖尿病模型。3 d后经血糖测试仪检测,血糖含量>16.65 mmol•L-1为制模成功。1组作为糖尿病模型对照组,另外2组7d后每天分别灌胃给予BH(465 mg•kg-1)和消渴丸(XKW,625 mg•kg-1),连续5周给药。每周1次测定给药过程中各组大鼠血糖变化。注射STZ 3 d和实验结束后,采用放射免疫分析方法分别测定各组大鼠血清中胰岛素含量。实验结束后观察各组大鼠胰岛β细胞的形态变化。结果:给予BH和消渴丸5周后,糖尿病BH给药组大鼠血糖由(18.3±1.8)mmol•L-1下降到(5.3±1.2) mmol• L-1,消渴丸对照组血糖由(18.4±1.9)mmol•L-1下降到(5.2±0.8) mmol•L-1,两组与糖尿病模型对照组[(19.9±1.9) mmol•L-1]比较差异均有显著性(P<0.001)。糖尿病BH给药组大鼠血清胰岛素含量由(18.8±2.3)mU• L-1升高到(42.2±3.5)mU•L-1, 消渴丸组大鼠血清胰岛素含量由(18.1±3.3)mU•L-1升高到(40.9±3.7)mU•L-1,两组与糖尿病模型对照组[(18.7±3.1) mU •L-1] 比较差异均有显著性(P<0.01),且基本接近正常对照组。糖尿病模型组大鼠的胰岛变小,细胞萎缩,胞核固缩、消失,分泌颗粒减少。应用BH和消渴丸5周后,上述异常变化消失且胰岛细胞形态趋向正常。结论:BH对糖尿病大鼠有降低血糖、升高血清胰岛素、恢复和保护胰岛β细胞的作用。  相似文献   
90.
应用IBM微机系统对31名正常人和31名喉疾病患者进行了声波、波谱描记,并与喉动态镜观察结果进行了比较,对声带的7种疾病的特异性进行了研究,认为二者结合可使喉发声功能的研究提高到新水平。  相似文献   
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