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排序方式: 共有2307条查询结果,搜索用时 15 毫秒
71.
Fiona Ashford Angus Best Steven J. Dunn Zahra Ahmed Henna Siddiqui Jordan Melville Samuel Wilkinson Jeremy Mirza Nicola Cumley Joanne Stockton Jack Ferguson Lucy Wheatley Elizabeth Ratcliffe Anna Casey Tim Plant The COVID- Genomics UK Consortium Joshua Quick Alex Richter Nicholas Loman Alan McNally 《Journal of clinical microbiology》2022,60(4)
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本研究选用油麻藤属三种植物进行组织培养,诱发愈伤组织,建立了基本方法并测定了愈伤组织的生长量和愈伤组织中左旋多巴的含量,结果表明:愈伤组织的生长量、生长速度和左旋多巴含量在种间有明显差异。愈伤组织中左旋多巴含量高于原种子中的含量,同一种培养材料不同继代愈伤组织中左旋多巴含量相对稳定并略有提高的趋势,愈伤组织中左旋多巴能从组织中排入培养基中。此外,讨论了用组织培养方法生产左旋多巴的可能性和固定化细胞培养等问题。 相似文献
74.
We report on the case of a middle-aged woman who suffers from recurrent right-sided ptosis. The ptosis is always complete with preserved ocular motility. Full recovery is the rule. The involvement of both the Müller’s muscle and levator palpebrae superioris is demonstrated clinically, pharmacologically, and by high-resolution magnetic resonance imaging. The results presented point towards a local pathology of the lid surface anatomy; the etiology, however, remains unknown. 相似文献
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Saskia PJ Verkleij Pim AJ Luijsterburg Sten P Willemsen Bart W Koes Arthur M Bohnen Sita MA Bierma-Zeinstra 《The British journal of general practice》2015,65(637):e530-e537
Background
The effectiveness of diclofenac versus paracetamol in primary care patients with pain caused by knee osteoarthritis is unclear.Aim
To assess the effectiveness of diclofenac compared with paracetamol over a period of 2, 4, and 12 weeks in patients with knee osteoarthritis.Design and setting
Randomised controlled trial in general practice.Method
There were 104 patients included in the study, they were aged ≥45 years consulting their GP with knee pain caused by knee osteoarthritis. Patients were randomly allocated to diclofenac (n = 52) or paracetamol (n = 52) for at least 2 weeks. Primary outcomes were daily knee pain severity, and knee pain and function measured with the Knee Injury and Osteoarthritis Outcome Score (KOOS).Results
Over a period of 2- and 4-weeks follow-up, no significant difference in daily knee pain was found between the patient groups: estimated differences of 0.5 (95% CI = −0.2 to 1.3) and −0.2 (95% CI = −1.0 to 0.7), respectively. Over the 12-weeks follow-up, no significant differences were found between both groups for KOOS pain: estimated difference of −2.8 (95% CI = −10.7 to 5.1) and KOOS function of −2.7 (−10.6 to 5.0).Conclusion
Over a period of 2- and 4-weeks follow-up no significant difference in daily measured knee pain severity was found between primary care patients with knee osteoarthritis taking paracetamol or diclofenac. Also, over a period of 12-weeks follow-up no significant differences were found regarding KOOS pain and KOOS function between both groups. Patients more frequently reported minor adverse events after taking diclofenac (64%) than paracetamol (46%). 相似文献79.
The occlusion of a coronary artery does not necessarily imply the existence of nonviable myocardium of that flow-dependent region, because the presence of a well developed collateral circulation may be a sufficient nutrient source. During an episode of increased demand for myocardial oxygen, this collateral blood supply may become insufficient, and symptoms of myocardial ischemia may arise. PTCA of the occluded vessel appears to be an attractive approach to relieve ischemia in this situation. The primary success of dilatation of totally occluded segments depends largely on the duration of the occlusion but also on anatomic factors such as total or functional occlusion, the length of the occluded segment, and good angiographic visualization of the coronary artery distal to the occlusion by collaterals. The primary success rate (+/- 60%) of PTCA of occluded vessels is lower than the success rate (greater than 90%) of PTCA of nonocclusive stenoses. Also the restenosis rate (+/- 40%) and subsequent recurrence rate of angina pectoris is higher, compared to the 30% restenosis rate after dilatation of conventional lesions. Newer percutaneous techniques such as lasers, newly designed guide wires, and intravascular imaging devices are necessary to increase the primary success rate. Whether these techniques will also improve the long-term results remains uncertain. 相似文献
80.
Styles LA; Schalkwijk CG; Aarsman AJ; Vichinsky EP; Lubin BH; Kuypers FA 《Blood》1996,87(6):2573-2578
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS. 相似文献