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151.
摘要目的建立测定维吾尔医药阿米乐努西达日蜜膏没食子酸含量的方法。方法采用高效液相色谱法,色谱柱:phenomenex C18(4.6 mm×250 mm,5 μm);检测波长:273 nm;流动相:甲醇 0.4%磷酸水溶液(10:90);流速:1.0 mL•min-1;进样量:10 μL;柱温:25 ℃。结果没食子酸在0.106~0.530 μg范围内峰面积与进样量具有良好的线性关系(r=0.999 7),平均加样回收率为97.9%(n=9),RSD=1.13%。结论该方法操作简便、准确、灵敏度高、重复性好,可为阿米乐努西达日蜜膏质量评价提供参考。  相似文献   
152.
Attributing individual deaths to extreme heat events (EHE) in Canada and elsewhere is important for understanding the risk factors, protective interventions, and burden of mortality associated with climate change. However, there is currently no single mechanism for identifying individual deaths due to EHE and different agencies have taken different approaches, including (1) vital statistics coding based on medical certificates of death, (2) probabilistic methods, and (3) enhanced surveillance. The 2018 EHE in Montréal provides an excellent case study to compare EHE deaths identified by these different approaches. There were 353 deaths recorded in the vital statistics data over an 8-day period, of which 102 were potentially attributed to the EHE by at least one approach and 251 were not attributed by any approach. Only nine of the 102 deaths were attributed to the EHE by all three approaches, 23 were attributed by two approaches, and 70 were attributed by only one approach. Given that there were approximately 50 excess deaths during the EHE, it remains unclear exactly which of the total 353 deaths should be attributed to the extreme temperatures. These results highlight the need for a more systematic and cooperative approach to EHE mortality in Canada, which will continue to increase as the climate changes.  相似文献   
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The function of ATP binding cassette protein A1 (ABCA1) is central to cholesterol mobilization. Reduced ABCA1 expression or activity is implicated in Alzheimer's disease (AD) and other disorders. Therapeutic approaches to boost ABCA1 activity have yet to be translated successfully to the clinic. The risk factors for AD development and progression, including comorbid disorders such as type 2 diabetes and cardiovascular disease, highlight the intersection of cholesterol transport and inflammation. Upregulation of ABCA1 can positively impact APOE lipidation, insulin sensitivity, peripheral vascular and blood–brain barrier integrity, and anti-inflammatory signaling. Various strategies towards ABCA1-boosting compounds have been described, with a bias toward nuclear hormone receptor (NHR) agonists. These agonists display beneficial preclinical effects; however, important side effects have limited development. In particular, ligands that bind liver X receptor (LXR), the primary NHR that controls ABCA1 expression, have shown positive effects in AD mouse models; however, lipogenesis and unwanted increases in triglyceride production are often observed. The longstanding approach, focusing on LXRβ vs. LXRα selectivity, is over-simplistic and has failed. Novel approaches such as phenotypic screening may lead to small molecule NHR modulators that elevate ABCA1 function without inducing lipogenesis and are clinically translatable.  相似文献   
156.
Antisera were raised against intact crotoxin (Crotalus durissus terrificus), Mojave toxin (Crotalus scutulatus scutulatus) and concolor toxin (Crotalus viridis concolor), as well as the subunits of crotoxin. Double immunodiffusion and enzyme-linked immunosorbent assays (ELISA) demonstrated antigenic similarity between these three purified toxins and their subunits. Additionally, when crotoxin antisera were pre-incubated with each of the three toxins before injection, the lethal activity of all were neutralized equally well. Antiserum was considerably more effective in neutralizing crotoxin in vivo when the toxin was injected i.m. than when injected i.v. Antisera against both intact crotoxin and its basic subunit were an order of magnitude more effective than crotoxin acidic subunit antiserum in crotoxin neutralization. Purified phospholipase A2 from Crotalus adamanteus and Crotalus atrox showed weak cross-reactivity with antisera raised against intact crotoxin and its subunits in the ELISA. Our results suggest that crotalid neurotoxins can be detected and neutralized by polyclonal antibodies raised against any intact toxin or basic subunit in this group of homologous toxins.  相似文献   
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Background: This paper represents, to our knowledge, the first national-level (United States) estimate of the economic impacts of vibriosis cases as exacerbated by climate change. Vibriosis is an illness contracted through food- and waterborne exposures to various Vibrio species (e.g., nonV. cholerae O1 and O139 serotypes) found in estuarine and marine environments, including within aquatic life, such as shellfish and finfish.Objectives: The objective of this study was to project climate-induced changes in vibriosis and associated economic impacts in the United States related to changes in sea surface temperatures (SSTs).Methods: For our analysis to identify climate links to vibriosis incidence, we constructed three logistic regression models by Vibrio species, using vibriosis data sourced from the Cholera and Other Vibrio Illness Surveillance system and historical SSTs. We relied on previous estimates of the cost-per-case of vibriosis to estimate future total annual medical costs, lost income from productivity loss, and mortality-related indirect costs throughout the United States. We separately reported results for V. parahaemolyticus, V. vulnificus, V. alginolyticus, and “V. spp.,” given the different associated health burden of each.Results: By 2090, increases in SST are estimated to result in a 51% increase in cases annually relative to the baseline era (centered on 1995) under Representative Concentration Pathway (RCP) 4.5, and a 108% increase under RCP8.5. The cost of these illnesses is projected to reach $5.2 billion annually under RCP4.5, and $7.3 billion annually under RCP8.5, relative to $2.2 billion in the baseline (2018 U.S. dollars), equivalent to 140% and 234% increases respectively.Discussion: Vibriosis incidence is likely to increase in the United States under moderate and unmitigated climate change scenarios through increases in SST, resulting in a substantial burden of morbidity and mortality, and costing billions of dollars. These costs are mostly attributable to deaths, primarily from exposure to V. vulnificus. Evidence suggests that other factors, including sea surface salinity, may contribute to further increases in vibriosis cases in some regions of the United States and should also be investigated. https://doi.org/10.1289/EHP9999a  相似文献   
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Early identification of patients at risk for severe coronavirus disease 2019 (COVID-19) is crucial for appropriate triage and determination of need for closer monitoring. Few studies have examined laboratory trends in COVID-19 infection and sought to quantify the degree to which laboratory values affect mortality. We conducted a retrospective cohort (n = 407) study of hospitalized patients with COVID-19 early in the course of the pandemic, from March 16th to April 8th, 2020 and compared baseline to repeat laboratory testing 72 hours into admission. The primary outcome was death. We found that rises of 25 mg/L C-reactive protein, 50 units/L lactate dehydrogenase, and 100 ng/mL ferritin were associated with 23%, 28%, and 1% increased odds of death, respectively. In contrast, changes in fibrinogen, D-dimer, white blood cell count, and creatinine in the first few days of hospital admission were not associated with mortality. These quantitative findings may assist clinicians in determining the risk of potential clinical decline in patients with COVID-19 and influence early management.  相似文献   
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