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71.
The global plastic production is reaching new altitudes every year. Growing production of petroleum-based plastics has incurred in disposal issues raising the concerns of plastic pollution and impact to the environment. These issues have encouraged innovation and research activities in the field of bioplastics, offering alternatives for conventional plastics. In recent years, global bioplastic production has also witnessed tremendous growth and expansion. Some of the main drivers of this growth are innovative biopolymers such as Polylactic acid (PLA) and Polyhydroxyalkanoates (PHAs). However, industrial expenses to produce bioplastics are much higher when compared to petroleum-derived plastics (e.g. industrial PHA production is estimated to be 5–10 times more expensive than petroleum-derived polymers). In this regard, globally many researchers have investigated for more environmentally friendly and cost-effective alternatives to produce plastics. One potential option to pursue would be to explore agri-food wastes and by-products for bioplastic production. This would not only reduce the volume of wastes and by-products, but also production costs incurred. This review paper provides an overview of bioplastics, including production methods and possibilities of industrial food waste valorization for bioplastic production.  相似文献   
72.
ABSTRACT

Objectives: This study aimed to compare the risk of fractures, acute myocardial infarction, atrial fibrillation, and ventricular arrhythmia among Danish citizens aged ≥ 65 which were new users of promethazine or domperidone, triazolam, loratadine, and betahistine. Secondly, the study aimed to perform a risk stratification to identify the most relevant predictors for the study outcomes.

Methods: The study period was 01/01/2015 to 31/12/2016. The data sources were the Danish registers. Each patient was followed for 90 days. A logistic regression model was used to compute the unadjusted and adjusted odds ratios (OR), and a conditional inference tree was used to identify the most relevant predictors for the study outcomes.

Results: Promethazine had a higher risk of hospitalization for atrial fibrillation than loratadine and betahistine (OR 1.58; 95% CI 1.07–2.63 and OR 3.22; 95% CI 1.69–7.14, respectively). For fractures, acute myocardial infarction, and ventricular arrhythmia hospitalizations, no statistically significant differences were found among drugs under investigation. The medical history of cardiac arrhythmia (OR 4.14; 95% CI 2.94–5.78, p < 0.0001) was the most relevant predictor for atrial fibrillation hospitalizations.

Conclusion: This study found an increased risk of atrial fibrillation hospitalization among promethazine users, and the risk was higher among patients with prior cardiac arrhythmia.  相似文献   
73.
Species-specific isotope dilution inductively coupled plasma mass spectrometry (SS ID ICP-MS) and high-performance liquid chromatography (HPLC) were used to obtain accurate and SI traceable results for methyl mercury in seafood samples such as clam, oyster and fish homogenate. The mass fractions of (62.3 ± 2.3) μg kg−1, (5.44 ± 0.36) μg kg−1 and (531 ± 19) μg kg−1 were obtained for MeHg (as Hg) in IAEA-461, IAEA-470 and IAEA-476, respectively. Direct isotope dilution mass spectrometry was performed for total mercury content then the content of inorganic mercury in selected samples was obtained by calculation. It was found that the content of inorganic Hg in IAEA-461, IAEA-470, and IAEA-476 was as: 328 μg kg−1, 16 μg kg−1, and 62 μg kg−1, respectively. Mathematical modelling of analytical procedure and evaluation of all parameters influencing final results were adequate for validation of measurement procedure, establishing traceability and estimating expanded uncertainty. Developed procedures were successfully applied in the characterization process of fish homogenate candidate reference material and in the calculation of assigned values in the frame of IAEA-476 inter-laboratory comparison study. Compatibility between obtained results and those derived from the certification campaign, organized by International Atomic Energy Agency on the same sample matrix (<2.6 % difference) further validated performed ID ICP-MS protocols.  相似文献   
74.
《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.  相似文献   
75.
《中国现代医生》2020,58(24):173-175+179
目的 探讨无痛内镜的护理安全管理的临床意义。方法 选择护理安全管理实施前(2019年2~6月)和实施后(2019年7~11月)在我院消化内镜室进行无痛胃镜检查的患者160例作为研究对象,实施前后分别作为对照组和观察组,每组80例。对照组实施常规护理,观察组在对照组基础上实施严格的护理安全管理。比较两组患者的护理质量评分、检查后的不良反应发生率、对护理工作的满意度以及医务人员职业暴露发生率。结果 观察组患者的护理质量评分为(97.28±2.60)分,显著高于对照组的(90.74±2.59)分(P0.05)。观察组的患者不良反应发生率为5.00%,显著低于对照组的31.25%(P0.05)。观察组的患者对护理工作的满意度为98.75%,显著高于对照组的85.00%(P0.05)。观察组的医务人员职业暴露发生率为7.50%,显著低于对照组的25.00%(P0.05)。结论无痛胃镜检查时严格执行护理安全管理,能提高护理质量和患者的满意度,降低患者的不良反应和医务人员的职业暴露发生率。  相似文献   
76.
The intestinal microbiota plays a critical role in food allergy development. However, little is known regarding the structure and composition of the intestinal microbiota in patients with wheat-dependent exercise-induced anaphylaxis (WDEIA). We examined the gut microbiota alterations in patients with WDEIA and the microbiota’s association with WDEIA. Fecal samples were collected from 25 patients with WDEIA and 25 healthy controls. Environmental exposure factors were obtained, serum total IgE, IgE specific to wheat, gluten, and ω-5 gliadin were measured. Fecal samples were profiled using 16S rRNA gene sequencing. The relative abundances of the bacterial genera Blautia (P < 0.05), Erysipelatoclostridium (P < 0.01), Akkermansia (P < 0.05) and Lachnospiraceae_NK4A136_group (P < 0.05) were significantly increased, while those of Lactobacillus (P = 0.001) and Dialister (P < 0.05) were significantly decreased in subjects with WDEIA. The microbial diversity did not differ between WDEIA patients and healthy controls. IgE specific to ω-5 gliadin was positively associated with the Oscillospira (r = 0.48, P < 0.05) and negatively associated with Leuconostoc (r = −0.49, P < 0.05). Total IgE levels were significantly negatively correlated with Bifidobacterium (P < 0.05). The gut microbiome compositions in WDEIA patients differed from those of healthy controls. We identified a potential association between the gut microbiome and WDEIA development. Our findings may suggest new methods for preventing and treating WDEIA.  相似文献   
77.
目的探讨床旁多普勒超声引导下经皮气管切开术(PDT)在重症脑出血患者中的应用价值。方法选取2014年1月—2019年4月南方医科大学附属小榄医院重症医学科监护治疗的重症脑出血患者126例,在ICU床旁采用超声引导下行PDT。术前采用超声进行检查,明确气管位置、周围组织及血管情况,确定穿刺部位及深度,指导术前气管导管退管。术中实时超声引导,确保手术安全。术后超声确认气管切开套管位置,筛查排除气胸等相关并发症。观察操作时间(从皮肤穿刺到成功置入气管套管时间)、一针穿刺成功率、置管成功率、气管插管意外脱管率;观察术中及术后并发症:出血量、血管/甲状腺损伤、气管后壁损伤、皮下气肿、气胸、低氧血症发生率等。结果126例患者手术均一次操作成功,一针穿刺成功率及置管成功率均为100%,未发生气管插管意外脱管。操作时间5~12 min,平均操作时间7.5 min。术中及术后未发生难以控制的大出血、严重低氧血症、血管/甲状腺损伤、气管后壁损伤、皮下气肿及气胸等并发症。结论对重症脑出血患者行床旁实时超声引导下行PDT,提高了手术的可视性、操作性和安全性,提高PDT成功率,降低相关并发症,具有良好的临床价值。  相似文献   
78.
The COVID-19 crisis has caused many issues across healthcare. In surgery, many operations have been cancelled with some surgeons losing their regular operating lists. During this time, technical expertise and decision making can deteriorate. In aviation after a prolonged period of absence from flying, this deficit in keeping skills and thinking up to date is known as being “out of currency” or “not current”. Although aviation and healthcare cannot be compared, numerous human factors concepts are applicable to both. In this article, we explore the likely impact of potentially prolonged absences in operating on surgical skills and psyche, and introduce the concept of a Surgical Skills Currency Barometer. We also discuss a “task-o-meter” thought experiment, and suggest practices which could be adopted to help protect surgeon workload from exceeding surgical capability when returning to operating following a period of prolonged absence.  相似文献   
79.
80.
目的:系统性评价程序性死亡因子1/程序性死亡因子1配体(PD-1/PD-L1)抑制剂对比常规疗法治疗癌症的有效性和安全性。方法:计算机全面检索PubMed、MEDLINE、EMBASE数据库,收集PD-1/PD-L1抑制剂治疗癌症的文献研究,检索时间为2000年1月1日至2019年6月30日。两位研究人员独立收集和整理资料,评价纳入文献研究的偏倚风险,应用Review Manager 5.3软件对纳入研究进行数据整理。结果:最终纳入11项随机对照试验,共6 295例研究对象,其中PD-1/PD-L1抑制剂试验组3 220例,常规疗法药物对照组3 075例。Meta分析结果显示,PD-1/PD-L1抑制剂试验组的客观反应率(ORR)[RR=1.87,95%CI(1.33,2.64),P<0.001]、完全缓解率(CR)[RR=2.45,95%CI(1.27,4.73),P<0.001]和部分缓解率(PR)[RR=1.81,95%CI(1.28,2.54),P<0.001]优于常规疗法对照组,结果均有统计学差异;在疾病控制率(DCR)[RR=1.03,95%CI(0.89,1.20),P=0.65]和疾病进展率(PD)[RR=1.16,95%CI(0.95,1.40),P=0.14]方面,两组比较无统计学差异;而在疾病稳定率(SD)[RR=0.72,95%CI(0.63,0.82),P<0.001]方面显示常规疗法对照组优于PD-1/PD-L1抑制剂试验组。药物安全性方面,不良反应发生率(AEs)[RR=0.96,95%CI(0.88,1.04),P=0.28]两组无统计学差异,但在3-5级不良反应发生率[RR=0.44,95%CI(0.28,0.68),P<0.001]方面,PD-1/PD-L1抑制剂试验组明显低于常规疗法对照组。结论:PD-1/PD-L1抑制剂与常规疗法药物相比,可明显提高癌症患者临床治疗的ORR、CR和PR,且出现3-5级不良反应发生率更低,从而证实PD-1/PD-L1抑制剂的有效性和安全性优于常规疗法。  相似文献   
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