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平贝碱乙的分离和鉴定   总被引:5,自引:0,他引:5  
本文报道了自东北平贝母(Fritillaria ussuriensis Maxim)中分得一种新的甾体生物碱,经光谱(IR,MS,1HNMR及13CNMR)解析和衍生物制备,推定其结构为5α,17β,22α-cevanine-3 β,6α,12α,14α,16β,20β-hexol,定名为平贝碱乙。  相似文献   
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抗CCT2单克隆抗体博来霉素A6偶联物可吸附胶体金颗粒(McAb-A6-Au)。电镜观察表明,在4℃,1h,表面有McAb-A6-Au颗粒的CEM细胞最高达78%;在37℃,4h,内化McAb-A6-Au颗粒的CEM细胞高达72%。而抗原性无关的U937细胞仅为14%。并且McAb-A6-Au颗粒能直接穿过细胞膜、核膜进入细胞浆和细胞核。37℃,1h已有10~18%的CEM细胞核内有McAb-A 6-Au颗粒。实验结果提示了单抗与博来霉素A6的偶联物与选择性地结合靶细胞,而且进入细胞速度快、穿透力强,有可能成为治疗白血病药物。  相似文献   
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Purpose:To determine and validate retinal vascular caliber measurements by using the confocal scanning laser ophthalmoscopy system. Retinal vasculature changes are often regarded as clinical markers for systemic disease.Methods:It was a prospective observational study conducted on 600 eyes of 300 normal subjects with no systemic or ocular illness from January 1, 2016 to June 30, 2017 in a tertiary referral eye center. Non-mydriatic infrared reflectance, blue reflectance, and blue peak blue autofluorescence fundus imaging were done on the confocal scanning laser ophthalmoscopy system. The dimensions of the retinal vessels were measured using inbuilt calipers at 1800 mm from the center of the optic disc. Internal and external dimensions were measured. Observer variation and its comparison using Image J software were assessed.Results:The median age was 29 years (18–50 years). Mean internal and external diameters for arterioles were 85.1 ± 12.4 mm and 105.0 ± 12.0 mm, and for venules were 133.8 ± 16.6 mm and 145.4 ± 16.1 mm, respectively. The mean internal and external wall thicknesses were 19.7 ± 8.0 mm and 11.0 ± 5.6 mm, and wall thickness-to-lumen ratios were 0.3 ± 0.1 and 0.1 ± 0.1, respectively. Arteriolar-to-venular ratio for lumen and vessel was 0.66 ± 0.1 and 0.74 ± 0.1, respectively. There was no statistically significant difference between age groups. Both inter- and intra-observer reproducibility was >95%. The Bland–Altman plot showed that the difference between measurements using both confocal scanning laser ophthalmoscopy and Image J software lies within the limits of agreement approximately 95% of the time.Conclusion:This is the first effort to develop a normative database by using a simple non-invasive confocal scanning laser ophthalmoscopy system with high observer reproducibility.  相似文献   
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Aim: To investigate the prevalence of medication‐related problems (MRPs) in patients attending aged care and memory disorder clinics and explore the potential role of a clinical pharmacist to obtain medication histories and identify unresolved MRPs. Methods: The clinical pharmacist interviewed patients and reviewed their medication regimens in the outpatient clinics. Clinical significance of pharmacist‐identified MRPs was rated by an independent expert panel using validated criteria. Results: Forty‐six patients (mean age 82 years) were reviewed. They took a median of nine medications, of which three were not recorded in the medical record. One hundred and thirteen MRPs (median 2.0 per patient) were identified by the pharmacist. Independent review rated 35% of MRPs as high or extreme risk. Thirty‐seven (33%) MRPs related to medications not recorded in the medical record. Conclusions: Medication‐related problems were present for most patients. Involvement of a clinical pharmacist resulted in a more comprehensive medication history and identified unresolved MRPs.  相似文献   
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