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981.
Onion-like graphitic structures are of great importance in different fields. Pentagons, heptagons, and octagons are essential features of onion-like graphitic structures that could generate important properties for diverse applications such as anodes in Li metal batteries or the oxygen reduction reaction. These carbon nanomaterials are fullerenes organized in a nested fashion. In this work, we produced graphitic nano onion-like structures containing phosphorus and nitrogen (NP-GNOs), using the aerosol assisted chemical vapor deposition method. The NP-GNOs were grown at high temperature (1020 °C) using ferrocene, trioctylphosphine oxide, benzylamine, and tetrahydrofuran precursors. The morphology, structure, composition, and surface chemistry of NP-GNOs were characterized using different techniques. The NP-GNOs showed diameters of 110–780 nm with Fe-based nanoparticles inside. Thermogravimetric analysis showed that NP-GNOs are thermally stable with an oxidation temperature of 724 °C. The surface chemistry analysis by FTIR and XPS revealed phosphorus–nitrogen codoping, and several functionalities containing C–H, N–H, P–H, P–O, P Created by potrace 1.16, written by Peter Selinger 2001-2019 O, C Created by potrace 1.16, written by Peter Selinger 2001-2019 O, and C–O bonds. We show density functional theory calculations of phosphorus–nitrogen doping and functionalized C240 fullerenes. We present the optimized structures, electronic density of states, HOMO, and LUMO wave functions for P-doped and OH-functionalized fullerenes. The P Created by potrace 1.16, written by Peter Selinger 2001-2019 O and P–O bonds attributed to phosphates or hydroxyl groups attached to phosphorus atoms doping the NP-GNOs could be useful in improving supercapacitor function.

Nitrogen–phosphorus doped graphitic nano onion-like structures.  相似文献   
982.
In 83 elderly breast cancer patients, oestrogen and progesterone receptors (ER, PgR), pS2 and cathepsin D (CathD) were evaluated for their possible prognostic role on disease-free survival (DFS). The biomarkers were determined on the same cytosol by using immunoradiometric assays, and the variables were considered on a continuous scale. Univariate analysis indicated a linear relationship between logarithmic hazard ratio (log(HR)) and the log(ER) and log(PgR) concentration, but a non-linear relationship between log(HR) and CathD. As regards pS2, there was no evidence of a relationship with log(HR). In multivariate analysis, log(ER) content did not have a significant prognostic role, whereas log(PgR) retained a significant prognostic role. As regards the predictive ability, log(PgR) was the best discriminator of outcome followed by CathD, whereas the contribution of log(ER) was negligible. In multivariate analysis, 2 models were considered: one with log(ER), pS2, CathD and the interaction between pS2 and CathD, and another with log(PgR), pS2, CathD and the interaction between pS2 and CathD. In the first model, log(ER) content did not have a significant prognostic role, whereas in the second model log(PgR) retained a significant prognostic role. Our findings indicate that the quantitative determination of pS2 and CathD, in addition to steroid receptors, on the same cytosolic fraction could be a complementary tool to describe all breast cancer patients rather than just the elderly and that the use of a continuous scale, instead of a simple dichotomous “status”, may improve the biological information supplied by the variables. Int. J. Cancer (Pred. Oncol.) 79:305–311, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
983.
Background. Prognostic factors in metastatic breast cancer continue to be identified. Previous adjuvant chemotherapy appeared to have poor prognosis in some studies but, despite this, the prior use of anthracyclines in the adjuvant setting has not been clearly established as an adverse prognostic factor once metastatic disease develops. Patients and methods. Patients (n=1,436) with stages I–IIIa breast cancer were surgically treated with/without radiotherapy and/or systemic adjuvant treatment. Of these, 297 patients who relapsed with metastatic disease constitute the sample population of this retrospective study. Survival, as a function of time since diagnosis of metastatic disease, was assessed in relation to the following factors: age, size of the primary tumor, grade, number of positive axillary nodes, type of surgery, type of adjuvant treatment administered, time to relapse, number of metastatic sites, presence of visceral metastases and type of treatment employed at the time of relapse. Results. In multivariable analysis three factors remained significant predictors of short survival time: more than 1 site of metastases (p=0.00003), shorter time to relapse (p=0.003) and the previous administration of anthracyclines as adjuvant therapy (p=0.005). Conclusions. The prior use of adjuvant anthracyclines, with other known clinical prognostic factors, confers a poorer outcome in metastatic disease, perhaps as a result of resistant clones selection or by induction of de novo resistance.  相似文献   
984.
Low molecular weight heparin, enoxaparin, has been one of most used drugs to fight the SARS-CoV-2 pandemic. Pharmacological properties of heparin recognize its specific ability, as with other oligosaccharides and glycosaminoglycan, to bind several types of viruses during their pass through the extracellular matrix of the respiratory tract, as well as its anticoagulant activity to prevent venous thromboembolism. Antithrombotic actions of enoxaparin have been testified both for inpatients with COVID-19 in regular ward and for inpatients in Intensive Care Units (ICUs). Prophylactic doses seem to be able to prevent venous thromboembolism (VTE) in inpatients in the regular ward, while intermediate or therapeutic doses have been frequently adopted for inpatients with COVID-19 in ICU. On the other hand, although we reported several useful actions of heparin for inpatients with COVID-19, an increased rate of bleeding has been recorded, and it may be related to several conditions such as underlying diseases with increased risks of bleeding, increased doses or prolonged administration of heparin, personal trend to bleed, and so on.  相似文献   
985.
It has been reported that the colors perceived behind closed eyes provide an indication of the psychophysical state of a subject. We discuss this phenomenon in the light of recently developed approaches to living organisms, based on the interplay between matter organization, biochemistry and electrodynamics. "When there is no energy, there is no color, no shape, no life." Caravaggio (1571-1610).  相似文献   
986.
Previous studies have shown a benefit of a strategy of direct angioplasty and stenting in patients with acute myocardial infarction (AMI) complicated by early cardiogenic shock. However, few data exist for the subset of patients with left main trunk disease complicated by AMI and cardiogenic shock. We performed an analysis of patients with AMI who underwent mechanical intervention between January 1995 and December 2000. Out of 1,433 patients with ST segment elevation AMI treated with primary coronary angioplasty (PTCA), 22 patients (1.5%) had left main disease (LMD) as the culprit lesion. Baseline characteristics were age, 66 +/- 11 years; female gender, 9%; diabetes, 14%; previous myocardial infarction, 14%; mean systolic blood pressure, 77 +/- 24 mm Hg; time to treatment, 4.8 +/- 2.2 hr; TIMI 0-1, 77%; collateral flow (Rentrop grade >or= 2) 9%. The primary success rate was 91%. Primary stenting was performed in 17 patients (77%). The in-hospital mortality rate was 50%. All deaths were due to refractory shock. The 6-month survival rate was 41% +/- 1%, while the event-free survival rate was 27% +/- 10%. At 6-month follow-up, the mortality rate increased to 59%; the target vessel revascularization rate was 14%. A percutaneous mechanical intervention strategy in patients with left main disease complicated by AMI is feasible and effective, and patients discharged alive have a good mid-term prognosis.  相似文献   
987.
Rewards are a broad category of stimuli inducing approach behavior to aid survival. Extensive evidence from animal research has shown that wanting (the motivation to pursue a reward) and liking (the pleasure associated with its consumption) are mostly regulated by dopaminergic and opioidergic activity in dedicated brain areas. However, less is known about the neuroanatomy of dopaminergic and opioidergic regulation of reward processing in humans, especially when considering different types of rewards (i.e., social and nonsocial). To fill this gap of knowledge, we combined dopaminergic and opioidergic antagonism (via amisulpride and naltrexone administration) with functional neuroimaging to investigate the neurochemical and neuroanatomical bases of wanting and liking of matched nonsocial (food) and social (interpersonal touch) rewards, using a randomized, between-subject, placebo-controlled, double-blind design. While no drug effect was observed at the behavioral level, brain activity was modulated by the administered compounds. In particular, opioid antagonism, compared to placebo, reduced activity in the medial orbitofrontal cortex during consumption of the most valued social and nonsocial rewards. Dopamine antagonism, however, had no clear effects on brain activity in response to reward anticipation. These findings provide insights into the neurobiology of human reward processing and suggest a similar opioidergic regulation of the neural responses to social and nonsocial reward consumption.  相似文献   
988.
There is no second-line standard of care universally accepted for platinum-refractory metastatic urothelial carcinoma. Immunotherapy and anti-VEGF(R) targeted therapies are 2 emerging strategies with promising though inconclusive results. We perform a systematic meta-analysis to assess the available options. We searched MEDLINE/PubMed, the Cochrane Library, and American society of clinical oncology (ASCO) Meeting abstracts to identify prospective studies. Data extraction was conduced according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. The measured outcomes were overall survival (OS) and progression free survival (PFS). Seven randomized controlled trials were selected for final analysis, with a total of 2,451 evaluable patients. Chemotherapy with vinflunine did not reduce the risk of progression (HR?=?1.11; 95%CI 0.78–1.57; P = .56) or death (HR?=?0.97; 95%CI 0.70–1.34; P?=?.87) compared to taxanes. Immunotherapy with anti-PD-1/PD-L1 mAb improved OS over chemotherapy (HR?=?0.81; 95% CI 0.71–0.92; P<.0009). The OS benefit of immunotherapy was retained when compared to taxanes, but not compared to vinflunine, although without a significant difference between the 2 subgroups (P?=?.30). A lack of PFS (HR?=?0.73; P?=?.08) and OS (HR?=?1.0; P?=?.99) benefit was observed with an anti-VEGF(R) plus chemotherapy compared to chemotherapy alone. No PFS (P?=?.14) or OS (P?=?.13) differences were detected when comparing anti-VEGF(R) ± chemotherapy and immunotherapy. Immunotherapy significantly improved OS compared to chemotherapy in metastatic urothelial carcinoma unselected for PD-L1 status. The addition of anti-VEGF(R) to chemotherapy did not provide any statistically significant benefit in terms of PFS or OS. Single agent taxanes or vinflunine can be considered given their similar efficacy but different toxicity profiles.  相似文献   
989.
990.
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