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71.
Mohammad Javed Ali 《Indian journal of ophthalmology》2021,69(1):36
Authorship is the currency of an academic career. Scientific publications have significant academic and financial implications. Several standard authorship guidelines exist, and the International Committee of Medical Journal Editors (ICMJE) is the most popular amongst them. There are increasing concerns about the ethics of publications with the rise of inappropriate authorship. The most important reason appears to be a lack of knowledge and awareness of the authorship guidelines and what actions constitute unethical behaviors. There is a need to incorporate standard guidelines in medical curricula and conduct structured training and education programs for researchers across the board. The current perspective describes the significant concepts of appropriate and inappropriate authorship, and the possible measures being formulated to shape the future of authorship. 相似文献
72.
Marti C Cole R Kalogeropoulos A Georgiopoulou V Butler J 《Current heart failure reports》2012,9(1):1-7
Diuretics and vasodilators have been the cornerstone of heart failure (HF) therapy for decades. Although not shown to reduce
mortality, diuretic and vasodilator therapy remain commonplace for treating acute decompensated HF, with diuretics being the
mainstay of therapy for the removal of excess fluid in all patients with HF. This article discusses results of recent trials
concerning diuretic or vasodilator therapy and HF, including the Diuretic Optimization Strategies Evaluation (DOSE) trial,
the Placebo-Controlled Randomized Study of the Selective A1 Adenosine Receptor Antagonist Rolofylline for Patients Hospitalized
With Acute Decompensated Heart Failure and Volume Overload to Assess Treatment Effect on Congestion and Renal Function (PROTECT),
and the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST), as well as results from
the Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure (ASCEND-HF) trial and the Preliminary
Study of Relaxin in Acute Heart Failure (Pre-RELAX-AHF). 相似文献
73.
Elevated levels of circulating proinflammatory cytokines and adipokines have been repeatedly associated with increased risk for clinically manifest (Stage C) heart failure in large cohort studies. However, the role of low-grade, subclinical inflammatory activity in the transition from risk factors (Stage A heart failure) to structural heart disease (Stage B heart failure) is less well understood. Recent evidence suggests that chronic low-grade inflammatory activity is involved in most mechanisms underlying progression of structural heart disease, including ventricular remodeling after ischemic injury, response to pressure and volume overload, and myocardial fibrosis. Inflammation also contributes to progression of peripheral vascular changes. 相似文献
74.
Nusaybah Alotaibi Hassan H. Hammud Ranjith Kumar Karnati Syed Ghazanfar Hussain Javed Mazher Thirumurugan Prakasam 《RSC advances》2020,10(30):17660
Recently, carbon nanostructures have attracted interest because of their unique properties and interesting applications. Here, CoC@SiO2-850 (3) and CoC@SiO2-600 (4) cobalt–carbon/silica nanocomposites were prepared by solid-state pyrolysis of anthracene with Co(tph)(2,2′-bipy)·4H2O (1) complex in the presence of silica at 850 and 600 °C, respectively, where 2,2′-bipy is 2,2′-bipyridine and tph is the terephthalate dianion. Moreover, Co(μ-tph)(2,2′-bipy) (2) was isolated and its X-ray structure indicated that cobalt(ii) has a distorted trigonal prismatic coordination geometry. 2 is a metal–organic framework consisting of one-dimensional zigzag chains within a porous grid network. 3 and 4 consist of cobalt(0)/cobalt oxide nanoparticles with a graphitic shell and carbon nanotubes embedded in the silica matrix. They were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). XPS revealed that the nanocomposites are functionalized with oxygen-containing groups, such as carboxylic acid groups. In addition, the presence of metallic cobalt nanoparticles embedded in graphitized carbon was verified by XRD and TEM. The efficiency of 3 for adsorption of crystal violet (CV) dye was investigated by batch and column experiments. At 25 °C, the Langmuir adsorption capacity of 3 for CV was 214.2 mg g−1 and the fixed-bed column capacity was 36.3 mg g−1. The adsorption data were well fitted by the Freundlich isotherm and pseudo-second-order kinetic model. The adsorption process was spontaneous and endothermic.A cobalt–carbon@silica nanocomposite was synthesized from a cobalt 2,2′-bipyridine terephthalate complex and its adsorption behavior towards crystal violet dye was tested using batch and column techniques. 相似文献
75.
Adil Saleem Yujun Zhang Hongyu Gong Muhammad K. Majeed M. Zeeshan Ashfaq Jie Jing Xiao Lin Mingming Sheng 《RSC advances》2020,10(25):15023
Carbon nanostructures (CNS) as a kind of reinforcement material can remarkably enhance the mechanical and thermal properties of ceramics. This research presents an analysis of the influence of CNS on the thermal conductivity and mechanical properties of SiCw/Si3N4 composites. The SiCw/Si3N4 composites containing various types of CNS e.g. carbon nanofibers (CNF), multi-walled carbon nanotubes (MWCNT) and graphene nano-platelets (GNP) were fabricated by hot-press sintering. XRD analysis confirmed a complete transformation of α-Si3N4 to β-Si3N4 and microstructural analysis shows a uniform distribution, as well as a pullout and bridging mechanism of CNS. The results revealed that the thermal conductivity and mechanical properties of SiCw/Si3N4 composites increased with the addition of CNS. Maximum values of fracture toughness (9.70 ± 0.8 MPa m1/2) and flexural strength (765 ± 58 MPa) have been achieved for the MWCNT-containing SiCw/Si3N4 composite, whereas the maximum values of Young''s modulus (250 ± 3.8 GPa) and hardness (27.2 ± 0.9 GPa) have been achieved for the CNF-containing SiCw/Si3N4 composite. Moreover, thermal conductivity also improved with the addition of CNS and reached a maximum value of 110.6 W m−1 K−1 for the CNF-containing SiCw/Si3N4 composite. This work provides a useful approach for the fabrication of high-performance multifunctional composites for emerging engineering applications.Carbon nanostructures (CNS) as a kind of reinforcement material can remarkably enhance the mechanical and thermal properties of ceramics. 相似文献
76.
Yunwei Wei Wei Zheng Malik Zeeshan Shahid Zhixiang Jiang Yuehua Li Zhongyao Duan Guangning Liu Xun Hu Cuncheng Li 《RSC advances》2020,10(17):10023
Compared with nanoscale quantum dots (QDs), the large-sized perovskite crystals not only possess better stability but also are convenient for application exploration. Herein, we develop a facile and efficient antisolvent vapor-assisted recrystallization approach for the synthesis of large-sized Cs4PbBr6 perovskite crystal microplates. In this method, for the first time, the shale-like Cs4PbBr6 microplates with lateral dimensions of hundreds of microns are fabricated by employing cetyltriethylammnonium bromide (CTAB) as a morphology-directing agent. FESEM, TEM, and AFM characterizations indicate that the as-obtained shale-like Cs4PbBr6 microplates are actually formed by 6–8 nm thick Cs4PbBr6 nanosheets with orientational stacking. Importantly, such highly crystalline Cs4PbBr6 microplates with shale-like morphology exhibit a narrow and intense green PL emission with a 59% PL quantum yield. Moreover, the planar structure of shale-like Cs4PbBr6 microplates makes it easy to form a preferred orientation on a substrate, which endow them with promising potential in optoelectronic devices such as lighting and displays.Highly luminescent shale-like Cs4PbBr6 microplates with hundreds of microns in lateral dimension and formed by thin nanosheets with orientational stacking. 相似文献
77.
Matthew Zapf Woody Denham Ermilo Barrera Zeeshan Butt JoAnn Carbray Chih Wang John Linn Michael Ujiki 《Surgical endoscopy》2013,27(12):4491-4498
Background
Laparoscopic cholecystectomy (LC) is the second most common general surgical operation performed in the United States, yet little has been reported on patient-centered outcomes.Methods
We prospectively followed 100 patients for 2 years as part of an institutional review board–approved study. The Surgical Outcomes Measurement System (SOMS) was used to quantify quality-of-life (QoL) values at various time points postoperatively.Results
Maximum pain was reported at 24 h (5.5 ± 2.2), and decreased to preoperative levels at 7 days (1.2 ± 2.3 vs. 2.0 ± 1.6, P = 0.096). Bowel function improved from before the operation to 3 weeks after surgery (10.7 ± 3.8 vs. 12.0 ± 3.2, P < 0.05), but then regressed to preoperative levels. Physical function worsened from before surgery (31.7 ± 6.2) to 1 week (27.5 ± 5.9, P < 0.0001), but surpassed preoperative levels at 3 weeks (33.5 ± 3.4, P < 0.01). Return to the activities of daily living occurred at 6.3 ± 4.7 days and work at 11.1 ± 9.0 days. Fatigue increased from before surgery (15.8 ± 6.2) to week 1 (20.7 ± 6.6, P < 0.0001) before improving at week 3 (14.0 ± 5.8, P < 0.01). Forty-four patients contacted the health care team 61 times before their 3 weeks appointment, most commonly for wound issues (26.2 %), pain (24.6 %), and gastrointestinal issues (24.6 %). Seventy-two percent reported that the procedure had no negative effect on cosmesis at 6 months. Satisfaction with the procedure was high, averaging 9.52 out of 11.Conclusions
QoL is significantly affected in the 24 h after LC but returns to baseline at week 3. Cosmesis and overall satisfaction are high, and QoL improvements are maintained in the long term except for bowel function, which regresses to preoperative levels of impairment. Analysis of patient-initiated contacts after LC may provide feedback on discharge counseling to increase patient satisfaction. 相似文献78.
Ajay P. Sharma Javed Mohammed Benson Thomas Nathan Lansdell Kambiz Norozi Guido Filler 《Pediatric nephrology (Berlin, Germany)》2013,28(8):1275-1282
Background
Nighttime blood pressure (BP) and systolic BP variability on ambulatory blood pressure monitoring (ABPM) have been strongly associated with target-organ damage in hypertensive adults. The clinical relevance of these variables in children with hypertension remains under-studied.Methods
The study group included children aged 5–18 years old referred to the outpatient nephrology clinic for an elevated casual BP who underwent an ABPM and echocardiography (ECHO) study and did not have secondary hypertension. The interpretation of ABPM parameters and left ventricular mass index (LVMI) was based on normative references.Results
Seventy-two children fulfilled the inclusion criteria. The association of various potential predictors including age, BMI z-score, casual BP z-score and ABPM parameters (BP z-score, BP load, nocturnal dipping and BP variability- within-subject standard deviation (SD) of BP) with LVMI was analyzed. On adjusted regression analysis, nighttime systolic BP load [standardized regression coefficient (β) 0.23; p?<?0.05] and daytime systolic BP variability (β 0.37; p?<?0.05) had significant association with LVMI.Conclusions
In children with primary hypertension, nighttime systolic BP load and daytime systolic BP variability had a stronger association with LVMI than casual BP and other ABPM parameters. Future longitudinal studies are needed to establish the causality among these variables. 相似文献79.
Background: Periodontitis may occur in patients with and without type 2 diabetes (T2D). It may be hypothesized that the gingival crevicular fluid (GCF) cytokine profile in patients with periodontitis with poorly controlled T2D may differ from the GCF cytokine profile in medically healthy individuals with periodontitis. The aim was to review the cytokine profiles in the GCF of patients with periodontitis with and without T2D. Methods: Databases were searched from 1988 to August 2011 using different combinations of various keywords. Titles and abstracts of articles that satisfied the eligibility criteria were screened by the authors and checked for agreement. Only articles published in English were included. Results: Ten studies were included. Two studies reported GCF concentrations of interleukin (IL)‐6 to be higher in patients with periodontitis with T2D compared to medically healthy patients with periodontitis. Two studies showed GCF IL‐6 levels to be higher in periodontitis with T2D compared to medically healthy subjects without periodontitis. In one study GCF levels of IL‐17, IL‐23, and interferon‐γ were higher in patients with periodontitis with T2D compared to medically healthy patients with periodontitis. In one study, GCF concentrations of IL‐8 were significantly higher in patients with periodontitis with T2D compared to medically healthy individuals with periodontitis. Three studies reported GCF levels of IL‐1α to be significantly higher in patients with periodontitis with T2D compared to medically healthy individuals with periodontitis. Conclusion: The GCF cytokine profile in patients with and without T2D seems to be governed by the intensity of periodontal inflammation and the role of T2D in this regard is rather secondary. 相似文献
80.
Mohammad A. Javaid Mohamed-Nur Abdallah Ahad S. Ahmed Zeeshan Sheikh 《Acta neurologica Belgica》2013,113(4):381-390
Matrix metalloproteinases (MMPs) are a family of extracellular proteases associated with extracellular matrix remodeling. They are involved in many physiological and reparative processes. MMPs can break down all extracellular constituents; therefore, their expression is very tightly regulated and their abnormal activity or over production has been linked to many diseases including multiple sclerosis (MS) which is a leading cause of non-traumatic disability in young adults in North America. Recently many studies, both in animals and humans, have been conducted to better elucidate the underlying causes, mechanisms and pathophysiology of MS. In this review, we discuss the potential role of pathological upregulation of MMPs in MS and future challenges which if properly addressed might help in development of potential cure for this disease. 相似文献