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81.
We report a general protocol for <i>ortho</i>-C–H fluoroalkoxylation of benzaldehydes and benzylic amines utilizing an inexpensive amino amide as a transient directing group. In the presence of an electrophilic fluorinating bystanding oxidant and fluorinated alcohols, a wide range of benzaldehydes and benzylic amines could be oxygenated selectively at the ortho positions to afford fluoroalkyl aryl ethers. This elegant approach would provide appealing strategies for synthesis of drug molecules and natural products.

A general protocol for ortho-C–H fluoroalkoxylation of benzaldehydes and benzylic amines was exploited by utilizing an inexpensive amino amide as a transient directing group.  相似文献   
82.
Studies with relatively large sample size as well as long-term follow-up focusing on adult craniopharyngioma (CP) patients are still lacking. We attempted to identify independent prognostic factors and establish a nomogram model to estimate survival rates for adult CP patients.The Surveillance, Epidemiology, and End Results database was used to obtain data on patients with CP. Univariable and multivariable Cox analyses were utilized to identify the prognostic factors of adult CP patients. A survival prediction model was constructed and its predictive performance was also assessed.A total of 991 patients (695 in training group and 296 in validation group) were eligible for final inclusion. Multivariate Cox analysis presented that age at diagnosis, marital status, race, tumor size, and surgery type were statistically significant prognostic factors for overall survival (all P < .05). A graphical predicting nomogram model was developed to calculate the predicted patients’ survival probabilities at 1, 2, 5, and 10 years. The concordance indexes were 0.708 ± 0.019 and 0.750 ± 0.025 for the training and validation samples, respectively, demonstrating favorable discrimination abilities. Similarly, the time-dependent area under curve also showed overall satisfactory discrimination ability. Favorable consistencies between the predicted and actual survival were presented according to the calibration curves.An easy-to-use nomogram, being proven to be with reliable discrimination ability and accuracy, was established to help predict overall survival for adult patients with CP using the identified significant prognostic factors.  相似文献   
83.
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   
84.
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   
85.
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   
86.
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   
87.
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   
88.
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   
89.
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   
90.
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   
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