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141.
采用 GC/MS/DS 分析了江苏连云港海州山产海州香薷 Elsholtzia splendens Nakai.ex F.Maekawa.挥发油成分,分离并鉴定了以香薷酮 Elsholtzia ketone.(85.27%)、去氢香薷酮 dehydro elsh-oltzione(2.00%)、β-石竹烯β-Caryophyllene(2.20%)、γ-榄香烯γ-element(1.54%)、3-辛醇3-Octanol(1.36%)、优葛缕酮 Eucarvone(1.04%)、波旁烯 Bourbonene(0.75%)、γ-木罗烯γ-muurolene(0.88%)、为主的37个成分。  相似文献   
142.
目的 分别采用1H核磁共振定量法和19F核磁共振定量法测定塞来昔布绝对含量,并将2种方法的测定结果与质量平衡法测定结果进行比较。方法 1H核磁共振定量法以CD3OD为溶剂,塞来昔布δ 6.92处质子峰作为定量峰,马来酸δ 6.33处为内标峰。在弛豫延迟时间10 s,采样时间4.01 s,扫描次数为32条件下采集混合物的氢谱。19F核磁共振定量法以CD3OD为溶剂,4-溴-2-氟-乙酰苯胺为内标,在谱宽240 ppm,中心频率-94.26 ppm,样品扫描次数为16次条件下采集氟谱,计算1H和19F核磁共振定量法的测试结果。结果 1H核磁共振定量法和19F核磁共振定量法测定结果相近,且与质量平衡法测定结果基本一致。结论 核磁共振定量法可以用来测定塞来昔布含量,具有准确、高效的优势。  相似文献   
143.
目的 探讨遗传性持续性胎儿血红蛋白增高症(H PF H)患者存在的珠蛋白基因突变类型及相关单核苷酸多态性(SNP)位点的基因型,分析HPFH中血红蛋白F(HbF)水平升高的分子机制.方法 收集HPFH标本,提取全血基因组DNA,采用Gap-PCR检测常见缺失型HPFH;采用PCR扩增与HbF水平升高相关的SNP位点,S...  相似文献   
144.
ObjectiveClinical specialty societies recommend long-acting reversible contraceptives (LARCs) as first-line contraception for adolescent women. We evaluated whether a combined educational and process improvement intervention enhanced LARC placement in primary care within an integrated health care system.MethodsThe intervention included journal clubs, live continuing education, point-of-care guidelines, and new patient materials. We conducted a retrospective cohort study across 3 time periods: baseline (January 2013?September 2015), early implementation (October 2015–March 2016), and full implementation (April 2016–June 2017). The primary outcome was the proportion of LARCs placed by primary care clinicians among women aged 13 to 18 years compared with gynecology clinicians.ResultsKaiser Foundation Health Plan of Colorado cared for approximately 20,000 women aged 13 to 18 years in each calendar quarter between 2013 and 2017. Overall, LARC placement increased from 7.0 per 1000 members per quarter at baseline to 13.0 per 1000 during the full intervention. Primary care clinicians placed 6.2% of all LARCs in 2013, increasing to 32.1% by 2017 (P < .001), including 45.5% of contraceptive implants. Clinicians who attended educational sessions were more likely to adopt LARCs than those who did not (17.9% vs 6.4% respectively, P = .009). Neither overall LARC placement rates (relative risk, 1.9; 95% confidence interval, 0.7?5.6) nor contraceptive implant rates (relative risk, 3.0; 95% confidence interval, 0.9?9.8) increased significantly in clinicians who attended educational activities.ConclusionsThis multimodal intervention was associated with increased LARC placement for adolescent women in primary care. The combination of education and process improvement is a promising strategy to promote clinician behavior change.  相似文献   
145.
An integral part of routine health checkups involves laboratory measurements on various analytes in the blood. It is then common to compare the value of two consecutive measurements sampled at different times from the same patient. A “significant” change requires an action (additional sample and/or clinical action). The current rule is to check whether the relative range of measurement is larger than a certain critical threshold. This rule should guarantee a specified confidence level (e.g., 95%), but its derivation was based on an approximation. We derive the exact distribution and show that it is related to the doubly noncentral F distribution. The currently used threshold values are compared with the exact ones, and some limited power calculations are presented to detect changes in the patient condition.  相似文献   
146.
Mutaz Dana 《Hemoglobin》2018,42(2):138-140
The major hemoglobin (Hb) during fetal life is fetal Hb (Hb F). It is mostly replaced by adult Hbs before birth and during the first year of life. In adults, where Hb F comprises <2.0% of the total Hb, it is not homogenously distributed among the red blood cells (RBCs) but is concentrated in a few RBCs, termed F-cells. Interestingly, for reasons that are unclear, Hb F increases in the maternal circulation during pregnancy. This increased Hb F could have two potential origins that are not mutually exclusive: A) maternal origin, due to inducing environment of Hb F in the maternal erythroid precursors; B) fetal origin, due to fetal cells crossing the placenta and entering the maternal circulation. The question we present herein is whether the observed increased Hb F in the maternal circulation during pregnancy is, at least partially, derived from the fetal origin. Peripheral blood was obtained from normal neonates (1–3 days old), adult men and pregnant and non pregnant women. The RBCs were stained for Hb F and carbonic anhydrase (CA) using a fetal cell count kit and analyzed by flow cytometry. Fetal and adult F-cells were distinguished by their expression of Hb F and CA. Fetal F-cells were Hb F++/CA?, while adult F-cells were Hb F+/CA+. Comparing pregnant and non pregnant women samples (n?=?10), we found six samples of pregnant women with 0.2–1.7% fetal cells, but none in the non pregnant group. These results support the possibility that at least part of the increase in Hb F during pregnancy is due to fetal cells entering the maternal circulation.  相似文献   
147.
Noninvasive imaging of tau aggregates with a positron emission tomography (PET) tracer is useful for the diagnosis and staging of Alzheimer’s disease (AD). Recently, we found that benzimidazopyridine (BIP) is an attractive scaffold for developing PET and single photon computed emission tomography tracers targeting tau aggregates. In this study, we designed and synthesized five novel 18F-labeled compounds with various substituted groups or atoms at the 7-position of the BIP scaffold. In in vitro autoradiographic studies, all 18F-labeled BIP derivatives selectively bound to tau aggregates deposited in AD brain sections. On the other hand, the initial brain uptake of these compounds was affected by the type of substituted group or halogen atom introduced into the 7-position of the BIP scaffold. Among these compounds, [18F]Me-BIPF showed the highest brain uptake (6.79% ID/g at 2 min postinjection) and 2 min/60 min ratio (3.59). These results suggest that appropriate introduction of the substituted group or atom into the 7-position of the BIP scaffold may be effective for developing useful tau PET tracers.  相似文献   
148.
Although there have been several case reports and simulation models of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission associated with air travel, there are limited data to guide testing strategy to minimize the risk of SARS-CoV-2 exposure and transmission onboard commercial aircraft. Among 9853 passengers with a negative SARS-CoV-2 polymerase chain reaction test performed within 72 hours of departure from December 2020 through May 2021, five (0.05%) passengers with active SARS-CoV-2 infection were identified with rapid antigen tests and confirmed with rapid molecular test performed before and after an international flight from the United States to Italy. This translates to a case detection rate of 1 per 1970 travelers during a time of high prevalence of active infection in the United States. A negative molecular test for SARS-CoV-2 within 72 hours of international airline departure results in a low probability of active infection identified on antigen testing during commercial airline flight.  相似文献   
149.
150.
[18F]Fluorination is usually carried out by nucleophilic substitution reactions entailing the use of stringent conditions. A number of novel techniques including silicon and boron‐based fluoride acceptor molecules, [18F]fluoro‐2‐deoxy‐ d ‐glucose and chelation of the Al18F complex have been employed recently to achieve [18F]radiolabelling of macromolecules. These approaches are reviewed herein. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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