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11.
In recent years, there has been a resurgence of interest in developing green and renewable alternate energy sources as a solution to the energy and environmental problems produced by conventional fossil fuel use. As a very effective energy transporter, hydrogen (H2) is a possible candidate for the future energy supply. Hydrogen production by water splitting is a promising new energy option. Strong, efficient, and abundant catalysts are required for increasing the efficiency of the water splitting process. Cu-based materials as an electrocatalyst have shown promising results for application in the Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) in water splitting. In this review, our aim is to cover the latest developments in the synthesis, characterisation, and electrochemical behaviour of Cu-based materials as a HER, and OER electrocatalyst, highlighting the impact that these advances have had on the field. It is intended that this review article will serve as a roadmap for developing novel, cost-effective electrocatalysts for electrochemical water splitting based on nanostructured materials with particular emphasis on Cu-based materials for electrocatalytic water splitting.In recent years, there has been a resurgence of interest in developing green and renewable alternate energy sources as a solution to the energy and environmental problems produced by conventional fossil fuel use. 相似文献
12.
D B Mumford I A Tareen M R Bhatti M A Bajwa M Ayub T Pervaiz 《Journal of psychosomatic research》1991,35(2-3):257-264
Among 600 medical clinic attenders in Lahore, Pakistan, screened using the Bradford Somatic Inventory in Urdu, significant differences in symptom endorsement between 'organic' and 'mood-disordered' patients were found in 14 BSI items. Counting only those symptoms reported as present on more than 15 days during the previous month, significant differences in symptom endorsement were found in 21 BSI items. Another 60 patients attending the same clinics were recruited to evaluate the BSI as a screening questionnaire for mood disorders. Each patient was interviewed by a psychiatrist and a diagnosis made according to DSM III-R and ICD-9. Optimal cutting points for the 14-item, 21-item and 44-item BSI were determined by Relative Operating Characteristic (ROC) analysis. The areas under the fitted ROC curves (an index of discriminating efficiency) were similar for the three versions. Using a cut-off score of 13/14, the BSI-21 identified DSM III-R psychiatric disorders with an estimated sensitivity of 75% and specificity of 75%. Assuming a 30% prevalence in medical clinics, a positive value of around 60% can be expected when screening for psychiatric disorders. 相似文献
13.
Raza A Lisak L Billmeier J Pervaiz H Mumtaz M Gohar S Wahid K Galili N 《Leukemia & lymphoma》2006,47(3):433-440
This phase II trial investigated the safety and preliminary efficacy of a topotecan/thalidomide combination therapy in patients with myelodysplastic syndrome who had refractory anemia with excess blasts (RAEB), RAEB with transformation, or chronic myelomonocytic anemia. Patients received three 21-day cycles of topotecan 1.25 mg/m2 on days 1-5, which was repeated for two additional cycles in patients whose bone marrow blast percentages did not decrease. Oral thalidomide was then started at 100 mg/day (with the dose escalated up to 300 mg/day if well tolerated) for up to 1 year. Patients were monitored throughout the trial for hematologic and clinical adverse events, and efficacy was assessed using International Working Group (IWG) criteria. Forty-five patients, mostly elderly (median age 68 years; range 52-79 years), were enrolled. Therapy was generally well tolerated compared to high-dose chemotherapy. Three patients died from disease progression/infections during topotecan therapy, and four patients discontinued topotecan because of high-grade neutropenia (two patients), syncope (one patient), or hip surgery (one patient). Of 24 patients who received thalidomide, three discontinued because of treatment-related toxicity. Thirty-eight patients were evaluable for response: nine (24%) had hematologic improvement and 13 (34%) had stable disease. Responses occurred in patients with all disease subtypes. Six patients achieved transfusion independence, and one patient had a trilineage response. Approximately one-third of the patients had decreases in bone marrow blasts of ≥50%. Therefore, a topotecan and thalidomide combination therapy is promising, although further studies are needed to determine the optimum doses and schedule. 相似文献
14.
Art and science of photodynamic therapy 总被引:4,自引:0,他引:4
1. Photodynamic therapy is an established modality for the treatment of solid tumours and other accessible lesions. Although the concept and practice of combining light with a photosensitizing agent for the treatment of disease states has been around for almost a century, the understanding of the art and science therein has been tremendously enhanced over the past few years. 2. Photosensitized reactions are dependent on the generation of reactive oxygen species, in particular singlet oxygen, which accounts for the damaging effects on biological macromolecules, such as membrane lipids and proteins. Therefore, compounds that give a good yield of (1)O(2) are used as photosensitizers. 3. The main photosensitizers used in the clinical setting belong to the photofrin family; however, newer and more effective sensitizers are being evaluated for their potential clinical effectiveness. 4. Light sources have moved from the use of white light with specific filters in the old days to the more recent use of monochromatic light sources, such as lasers, to more sophisticated light-emitting diodes. However, dosimetry remains a big issue mainly because of difficulties in establishing the optimum treatment conditions for an approach that requires the fine-tuning of several variables, such as sensitizer and light doses and drug-to-light interval, as well as the issues of skin photosensitivity and low selectivity. A newer development to circumvent these and provide a broader application for this concept has been the phenomenon of photo-activation, whereby photo-exposure of chromophores to generate novel, small biologically active compounds has been demonstrated successfully. 5. The aim of the present review was to provide a general overview of the art and science of photodynamic therapy and to highlight some of the issues and recent developments in further advancing this modality of treatment. 相似文献
15.
A case of prostatic adenocarcinoma associated with extensive cutaneous metastases and malignant acanthosis nigricans is reported. Pertinent literature is reviewed. The pathogenesis of the possible mechanism of the development of cutaneous metastases in this as well as other related cases is discussed. 相似文献
16.
Fahad Pervaiz Mansoor Pervaiz Nabeel Abdur Rehman Umar Saif 《Journal of medical Internet research》2012,14(5)
Background
The Google Flu Trends service was launched in 2008 to track changes in the volume of online search queries related to flu-like symptoms. Over the last few years, the trend data produced by this service has shown a consistent relationship with the actual number of flu reports collected by the US Centers for Disease Control and Prevention (CDC), often identifying increases in flu cases weeks in advance of CDC records. However, contrary to popular belief, Google Flu Trends is not an early epidemic detection system. Instead, it is designed as a baseline indicator of the trend, or changes, in the number of disease cases.Objective
To evaluate whether these trends can be used as a basis for an early warning system for epidemics.Methods
We present the first detailed algorithmic analysis of how Google Flu Trends can be used as a basis for building a fully automated system for early warning of epidemics in advance of methods used by the CDC. Based on our work, we present a novel early epidemic detection system, called FluBreaks (dritte.org/flubreaks), based on Google Flu Trends data. We compared the accuracy and practicality of three types of algorithms: normal distribution algorithms, Poisson distribution algorithms, and negative binomial distribution algorithms. We explored the relative merits of these methods, and related our findings to changes in Internet penetration and population size for the regions in Google Flu Trends providing data.Results
Across our performance metrics of percentage true-positives (RTP), percentage false-positives (RFP), percentage overlap (OT), and percentage early alarms (EA), Poisson- and negative binomial-based algorithms performed better in all except RFP. Poisson-based algorithms had average values of 99%, 28%, 71%, and 76% for RTP, RFP, OT, and EA, respectively, whereas negative binomial-based algorithms had average values of 97.8%, 17.8%, 60%, and 55% for RTP, RFP, OT, and EA, respectively. Moreover, the EA was also affected by the region’s population size. Regions with larger populations (regions 4 and 6) had higher values of EA than region 10 (which had the smallest population) for negative binomial- and Poisson-based algorithms. The difference was 12.5% and 13.5% on average in negative binomial- and Poisson-based algorithms, respectively.Conclusions
We present the first detailed comparative analysis of popular early epidemic detection algorithms on Google Flu Trends data. We note that realizing this opportunity requires moving beyond the cumulative sum and historical limits method-based normal distribution approaches, traditionally employed by the CDC, to negative binomial- and Poisson-based algorithms to deal with potentially noisy search query data from regions with varying population and Internet penetrations. Based on our work, we have developed FluBreaks, an early warning system for flu epidemics using Google Flu Trends. 相似文献17.
18.
Iqbal MP Bajaj DR 《Journal of the College of Physicians and Surgeons--Pakistan : JCPSP》2007,17(8):495-496
Disabling pansclerotic morphoea of children is a clinical subset of morphoea that tends to involve deeper structures and progresses relentlessly. This is a case of 09 years old girl who developed morphoea in pansclerotic form on limb and in plaque form on abdomen. The combination is rare and resulted in severe shortening and functional disability of the involved limbs. 相似文献
19.
Aamer Saeed Haroon Mehfooz Muhammad Faisal Pervaiz Ali Channar 《Journal of Asian natural products research》2017,19(11):1114-1123
Steroids and terpenoids are among the most biologically significant classes of natural products possessing a variety of biological activities. The replacement of one or more oxygen atoms in a steroid or terpenoid molecule by a heteroatom affects the chemical properties of that particular steroid or terpenoid, and that replacement often results in alterations of its biological properties, which is sometimes valuable. One possible modification is the thionation that could have some influence on such activity. Among the various thionating reagents, Lawesson’s reagent was found to be most suitable and showed versatile properties, including chemoselectivity and functional group tolerance. In this review, we present the role of Lawesson’s reagent in the synthesis of thioanalogues of natural steroids and terpenoids. 相似文献
20.
An expedient synthesis of N‐(1‐(5‐mercapto‐4‐((substituted benzylidene)amino)‐4H‐1,2,4‐triazol‐3‐yl)‐2‐phenylethyl)benzamides as jack bean urease inhibitors and free radical scavengers: Kinetic mechanism and molecular docking studies 下载免费PDF全文
Aamer Saeed Fayaz Ali Larik Pervaiz Ali Channar Haroon Mehfooz Mohammad Haseeb Ashraf Qamar Abbas Mubashir Hassan Sung‐Yum Seo 《Chemical biology & drug design》2017,90(5):764-777
In this study, some new azomethine‐triazole hybrids 5a–5l derived from N‐benzoyl‐L‐phenylalanine were synthesized and characterized. The synthesized compounds showed first‐rate, urease inhibition, and compounds 5c and 5e were found to be most effective inhibitors with 0.0137 ± 0.00082 μm and 0.0183 ± 0.00068 μm , respectively (thiourea 15.151 ± 1.27 μm ). The kinetic mechanism of urease inhibition revealed the compounds 5c and 5e to be non‐competitive inhibitors, whereas compounds 5d and 5j were found to be of mixed‐type inhibitors. Docking studies also indicated better interaction patterns with urease enzyme. The results of enzyme inhibition, kinetic mechanism and molecular docking suggest that these compounds can serve as lead compounds in the design of more effective urease inhibitors. 相似文献