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排序方式: 共有261条查询结果,搜索用时 31 毫秒
71.
樟叶胡椒中新木脂素成分的研究 总被引:3,自引:0,他引:3
自胡椒科胡椒属植物樟叶胡椒(Piper polysyphorum C. DC)中分离到六个新木脂素(neolignans)类化合物,经光谱(UV,IR,MS,1H-NMR,13C-NMR,2D-NMR,CD)分析及衍生物制备,确定Ⅱ为新化合物,即threo-△7-7-羟基-3,4,5,3′,5′-五甲氧基-8-O-4′-新木脂素,为一对对映体,命名为樟叶素(polysyphorin),Ⅰ,Ⅲ,Ⅳ为新的对映体,分別为(+)-virolongin,(+)-grandisin及(+)-lancifolin D.化合物Ⅴ为南藤素(wallichinine),Ⅵ为山蒟素D(hancinone D)。血小板活化因子(PAF)受体结合实验及PAF引起的血小板聚集实验证明化合物Ⅰ~Ⅴ具有明显的抑制活性。 相似文献
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73.
赛庚啶对氧自由基的清除作用 总被引:18,自引:0,他引:18
赛庚啶(Cyp)对Fenton反应生成的·OH有较强的直接清除作用(EC50为54μmol/L),并明显抑制·OH的生成速率(IC50为22 μmol/L),且作用明显比·OH特异性清除剂甘露醇强(其EC50和IC50分别为22.7 mmol/L和10.7mmol/L)。Cyp对大鼠腹腔多形核白细胞(PMNs)产生的O2也有一定的清除作用,其IC50为179 μmol/L。提示Cyp的抗心肌损伤作用可能至少部分与其清除氧自由基作用相关。 相似文献
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Over-the-counter emergency contraception: a feasible option 总被引:1,自引:1,他引:0
Matheson CI; Smith BH; Flett G; Bond CM; Kennedy EJ; Michie C; Duthie I 《Family practice》1998,15(1):38-43
76.
FE Lithander A-T McGill AK MacGibbon BH McArdle SD Poppitt 《Lipids in health and disease》2008,7(1):41
Background
Phosphatidylethanolamine (PE) is a phospholipid which is biosynthesized into long chain N-acylethanolamines (NAEs) including oleoylethanolamide (OEA), a known inhibitor of food intake. The aim of this study was to investigate whether PE-containing lipids can also inhibit intake. This was a 4 treatment intervention where 18 male participants were given a high-fat test breakfast (2.5MJ, 53 en% fat) containing (i) high-phospholipid, high-PE lipid (ii) high-phospholipid, medium-PE lipid (iii) no-phospholipid, no-PE control lipid or (iv) water control, in a randomised cross-over. Visual analogue scales (VAS) were used to assess post-ingestive hunger and satiety, and energy intake (EI) was measured at an ad libitum lunch meal after 3.5hours. 相似文献77.
Tracey L Schubert BSc Emma BH Hume BSc PhD Mark DP Willcox BSc PhD 《Clinical & experimental optometry》2008,91(2):148-155
Background: Staphylococcus is the leading cause of microbial keratitis. Staphylococcus aureus isolated from ocular infections with resistance to a wide range of antibiotics, including the commonly prescribed fluoroquinolones, is emerging. The aim of this study was to determine the current antibiotic susceptibilities of ocular S. aureus isolates and also determine whether isolates from different adverse events or those with similar antimicrobial susceptibilities are related. Methods: A collection of 55 S. aureus strains from ocular adverse events were analysed for antibiotic susceptibility using disc diffusion (CDS method) and typed using PCR‐ribotyping and pulsed‐field gel electrophoresis (PFGE). Results: S. aureus isolated from symptomatic ocular adverse events in the USA exhibited greater resistance to antibiotics than did those isolated from symptomatic ocular adverse events in Australia or India (p < 0.05). A larger proportion of ulcerative keratitis isolates was found to be resistant to antibiotics than isolates from conjunctivitis. PFGE analysis separated related isolates determined by ribotype, on the basis of the adverse event caused by the isolate. Isolates were related within geographical regions and adverse event types. Conclusions: Similar isolates within a geographical location cause adverse events but there is a genetic difference between isolates causing corneal adverse events and those causing conjunctivitis. Isolates from corneal adverse events were more resistant to antibiotics, with those from the USA exhibiting the greatest resistance. This suggests that virulence may correlate with increased resistance to antibiotics. 相似文献
78.
Moser RP Jr; Vinh TN; Ros PR; Smirniotopoulos JG; Madewell JE; Berrey BH 《Radiology》1987,164(1):211-214
A study was done of 13 cases of biopsy-proved Paget disease in which the disease involved the anterior tibial tubercle with extension into the metaphysis and diaphysis, but without apparent involvement of the proximal tibial epiphysis. Case data were obtained from archives containing more than 350 cases of Paget disease. Age, sex, symptoms, serum alkaline phosphatase level, and histologic and radiographic appearance of the lesions were evaluated. Patients were young at clinical presentation, averaging 36 years of age. In five of six patients the serum alkaline phosphatase level was normal. The proximal extent of the disease was the anterior tibial tubercle rather than the proximal epiphysis. Radiographic patterns ranged from predominantly lytic to mixed lytic and blastic to predominantly blastic, and the lesion was marginated by a flame-shaped configuration. The radiographic appearance of Paget disease of the anterior tibial tubercle is characteristic and should be sufficient to suggest the diagnosis and preclude biopsy. 相似文献
79.
To evaluate the pathoanatomic findings of mitral valve stenosis and changes after percutaneous balloon valvuloplasty (PBV), magnetic resonance (MR) imaging was performed in 23 patients. The patients were imaged with a 2.0-T system within 1 week before and 3-10 days after PBV. The angle of the interatrial septum was measured on the transverse image to facilitate a successful transseptal puncture. On MR images, the mean transverse and anteroposterior diameters of the left atrium at the level of the aortic root in the ventricular diastolic phase decreased significantly after PBV. Areas of flow-related intraluminal signal intensity detected in the left atrial cavity of 17 patients (74%) before the procedure disappeared in 15 patients after the procedure. Other MR imaging findings after PBV were the disappearance of intraluminal signal intensity in the pulmonary artery, normal curvature of the interatrial and interventricular septa, and pericardial effusion as a complication. MR imaging was thought to provide useful information before and after PBV in patients with mitral stenosis. 相似文献
80.