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91.
《Clinical oncology (Royal College of Radiologists (Great Britain))》2020,32(6):347-353
The current COVID-19 pandemic presents a substantial obstacle to cancer patient care. Data from China as well as risk models suppose that cancer patients, particularly those on active, immunosuppressive therapies are at higher risks of severe infection from the illness. In addition, staff illness and restructuring of services to deal with the crisis will inevitably place treatment capacities under significant strain. These guidelines aim to expand on those provided by NHS England regarding cancer care during the coronavirus pandemic by examining the known literature and provide guidance in managing patients with urothelial and rarer urinary tract cancers. In particular, they address the estimated risk and benefits of standard treatments and consider the alternatives in the current situation. As a result, it is recommended that this guidance will help form a framework for shared decision making with patients. Moreover, they do not advise a one-size-fits-all approach but recommend continual assessment of the situation with discussion within and between centres. 相似文献
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Michelle Linda Ferderbar Thomas E. Doyle Reza Samavi David Koff 《Journal l'Association canadienne des radiologistes》2019,70(2):119-124
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization. 相似文献
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Kayode Olayinka Afolabi Benson Chuks Iweriebor Chikwelu Lawrence Obi Anthony Ifeanyi Okoh 《Transboundary and Emerging Diseases》2019,66(1):412-421
The porcine circovirus type 2 (PCV2) is a swine infectious viral pathogen of great significance in global swine herds. It was recently detected at another Province of South Africa sequel to the first detection of North American‐like strain (PCV2a) at Gauteng about two decades ago, but there is a dearth of information about the genomic features and diversity of the viral strains in circulation within the country and the entire sub‐Saharan Africa region. To date, only one complete genome of the virus from South Africa is available on global data base. This current effort is therefore geared towards the full‐genome characterization of the circulating PCV2 strains in the pigs of Eastern Cape Province. With the use of conventional polymerase chain reaction method, fifteen complete PCV2 genomes were successfully amplified, sequenced and assembled from field samples obtained from non‐vaccinated pigs in the region. Neighbor Joining and Maximum Likelihood phylogenetic analyses of the ORF2 gene and full genomes unanimously showed that most of the assembled genomes (11) belong to genotype PCV2b. Furthermore, three of the characterized sequences formed clade with other reference mutant PCV2b and PCV2b subtype 1C (i.e. PCV2d) strains from the USA, China and South Korea. The last sequence, however, clustered with other reference strains belonging to PCV2 intermediate clade 2 (PCV2‐IM2), recently identified in a global PCV2 strains phylogenetic analysis. This study reports the first complete genome sequences of PCV2b, PCV2d and PCV2‐IM2 in pigs from South Africa, and it gives a possible insight into the genetic characteristics and variability of the viral strains presently in circulation within the country. It further emphasizes the need for more stringent measures in curtailing the introduction and spread of transboundary swine pathogens in the country and entire Southern African region. 相似文献
98.
目的:观察灯盏乙素(Scu)对β淀粉样蛋白(Aβ)诱导的细胞模型中1,4,5-三磷酸肌醇受体(IP3R)-Ca2+途径的影响,探讨其在阿尔茨海默病(AD)病程中可能发挥的积极作用。方法:选用神经母细胞瘤细胞分为对照组、Scu处理组、Aβ处理组、Aβ+Scu (高、中、低)处理组及Aβ+IP3R拮抗剂组,用CCK-8法筛选药物浓度并检测各组细胞生存率;用酶联免疫吸附法检测各组细胞中1,4,5-三磷酸肌醇(IP3)的含量;用蛋白印迹和实时荧光定量聚合酶链反应方法检测各组细胞IP3R和凋亡相关因子Caspase-3、Bcl-2、Bax的蛋白及mRNA的表达水平;用激光共聚焦显微镜观察各组细胞内Ca2+浓度的变化;用AnnexinV/PI双染法测定各组细胞的凋亡率。结果:与对照组和Scu处理组相比,Aβ处理组细胞存活率下降,IP3含量升高,IP3R、Bax和Caspase-3的蛋白及mRNA表达上调,Bcl-2蛋白及mRNA的表达下调,细胞胞浆内Ca2+浓度及细胞凋亡率升高;Aβ+Scu处理组细胞中各检测指标的变化与Aβ处理组的结果正好相反,IP3R通道下游指标的变化与Aβ+IP3R拮抗剂组基本一致。结论:Scu能够下调通路蛋白IP3、IP3R的表达,抑制Aβ介导的Ca2+内流所致的细胞凋亡,可能通过对IP3R-Ca2+途径的调控来影响AD病程。 相似文献
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BackgroundExcessive consumption of ethanol is known to activate the mTORC1 pathway and to enhance the Collapsin Response Mediator Protein-2 (CRMP-2) levels in the limbic region of brain. The latter helps in forming microtubule assembly that is linked to drug taking or addiction-like behavior in rodents. Therefore, in this study, we investigated the effect of lacosamide, an antiepileptic drug and a known CRMP-2 inhibitor, which binds to CRMP-2 and inhibits the formation of microtubule assembly, on ethanol-induced conditioned place preference (CPP) in mice.MethodsThe behavior of mice following ethanol addiction and withdrawal was assessed by performing different behavioral paradigms. Mice underwent ethanol-induced CPP training with alternate dose of ethanol (2 g/kg, po) and saline (10 ml/kg, po). The effect of lacosamide on the expression of ethanol-induced CPP and on ethanol withdrawal associated anxiety and depression-like behavior was evaluated. The effect of drug on locomotor activity was also assessed and hippocampal CRMP-2 levels were measured.ResultsEthanol-induced CPP was associated with enhanced CRMP-2 levels in the hippocampus. Lacosamide significantly reduced the expression of ethanol-induced CPP and alleviated the levels of hippocampal CRMP-2 but aggravated withdrawal-associated anxiety and depression in mice.ConclusionThe present study demonstrated the beneficial effect of lacosamide in attenuation of expression of ethanol induced conditioned place preference via reduction of hippocampal CRMP-2 level. These findings suggest that lacosamide may be investigated further for ethanol addiction but not for managing withdrawal. 相似文献
100.
《Saudi Pharmaceutical Journal》2020,28(10):1243-1252
The novel coronavirus outbreak has reported to be rapidly spreading across the countries and becomes a foremost community health alarm. At present, no vaccine or specific drug is on hand for the treatment of this infectious disease. This review investigates the drugs, which are being evaluated and found to be effective against nCOVID-19 infection. A thorough literature search was performedon the recently published research papers in between January 2020 to May 2020, through various databases like “Science Direct”, “Google Scholar”, “PubMed”,“Medline”, “Web of Science”, and “World Health Organization (WHO)”. We reviewed and documented the information related with the current and future aspects for the management and cure of COVID-19. As of 21st July 2020 a total of 14,562,550 confirmed cases of coronavirus and 607,781 deaths have been reported world-wide. The main clinical feature of COVID-19 ranges from asymptomatic disease to mild lower respiratory tract illness to severe pneumonia, acute lung injury, acute respiratory distress syndrome (ARDS), multiple organ dysfunction, and death. The drugs at present used in COVID-19 patients and ongoing clinical trials focusing on drug repurposing of various therapeutic classes of drug e.g. antiviral, anti-inflammatory and/or immunomodulatory drugs along with adjuvant/supportive care. Many drugs on clinical trials shows effective results on preliminary scale and now used currently in patients. Adjuvant/supportive care therapy are used in patients to get the best results in order to minimize the short and long-term complications. However, further studies and clinical trials are needed on large scale of population to reach any firm conclusion in terms of its efficacy and safety. 相似文献