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Cerebral hemorrhagic risk of aspirin or heparin therapy with thrombolytic treatment in rabbits 总被引:4,自引:0,他引:4
W M Clark K P Madden P D Lyden J A Zivin 《Stroke; a journal of cerebral circulation》1991,22(7):872-876
We studied the incidence of cerebral hemorrhage in an animal model of embolic stroke to determine the safety of aspirin, heparin, and tissue plasminogen activator therapies. We occluded the middle cerebral arteries of rabbits with labeled blood clots and administered either tissue plasminogen activator, heparin, aspirin, tissue plasminogen activator plus aspirin, tissue plasminogen activator plus heparin, or saline at various times after stroke. Compared to saline controls, both the aspirin-only and the tissue plasminogen activator-plus-aspirin groups had a significantly higher incidence of cerebral hemorrhage, whereas the heparin and tissue plasminogen activator combination groups did not. We conclude that aspirin antiplatelet therapy alone may increase the risk of hemorrhagic infarction, whereas heparin or tissue plasminogen activator therapy appears to be relatively safe. 相似文献
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Carel Bron Michel Wensing Jo LM Franssen Rob AB Oostendorp 《BMC musculoskeletal disorders》2007,8(1):107
Background
Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders. 相似文献5.
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Metabolism is one of the major determinants for age-related changes in susceptibility to chemicals. Aldehydes are highly reactive molecules present in the environment that also can be produced during biotransformation of xenobiotics and endogenous metabolism. Although the lung is a major target for aldehyde toxicity, early development of aldehyde dehydrogenases (ALDHs) in lung has been poorly studied. The expression of ALDH in liver and lung across ages (postnatal day 1, 8, 22, and 60) was investigated in Wistar-Han rats. In adult, the majority of hepatic ALDH activity was found in mitochondria, while cytosolic ALDH activity was the highest contributor in lung. Total aldehyde oxidation capability in liver increases with age, but stays constant in lung. These overall developmental profiles of ALDH expression in a tissue appear to be determined by the different composition of ALDH isoforms within the tissue and their independent temporal and tissue-specific development. ALDH2 showed the most notable tissue-specific development. Hepatic ALDH2 was increased with age, while the pulmonary form did not. ALDH1 was at its maximum value at postnatal day 1 (PND1) and decreased thereafter both in liver and lung. ALDH3 increased with age in liver and lung, although ALDH3A1 was only detectible in lung. Collectively, the present study indicates that, in the case of aldehyde exposure, the in vivo responses would be tissue and age dependent. 相似文献
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The long-stem bipolar prosthesis in surgery of the hip 总被引:2,自引:0,他引:2
More than 500 hips, with either displaced fractures of the femoral neck or primary or revision total hip arthroplasty, were treated by a straight, long-stem (305-mm), Bateman-type bipolar model (BBM). The BBM was not porous coated, and it is not cemented in place. The femoral component is secured in the femoral canal by means of biomechanical fixation. It is biologic by bone ingrowth through the fenestration in the proximal neck. It is mechanical by a snug fit in the isthmus and by three-point fixation within the shaft. The removed femoral head is morselized in the bone mill and packed into the prepared femoral canal to enhance a tight fit. The collar of the BBM transfers stress to the calcar. Postoperative roentgenograms show incorporation of bone graft within the fenestration of the prosthesis and no stress shielding of the calcar. The acetabulum requires reaming only if it is shallow or asymmetric. It usually presents no problem except in revision total hip arthroplasty. The present authors have used the BBM almost exclusively since 1981. After eight years, the BBM has stood up well to the test of time and presented few major problems. 相似文献
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L Staiano-Coico J M Hefton C Amadeo I Pagan-Charry M R Madden C Cardon-Cardo 《The Journal of trauma》1990,30(8):1037-42; discussion 1043
Epidermal cell cultures were grown in keratinocyte-conditioned medium for use as burn wound grafts; the melanocyte composition of the grafts was studied under a variety of conditions. Melanocytes were identified by immunohistochemistry based on a monoclonal antibody (MEL-5) that has previously been shown to react specifically with melanocytes. During the first 7 days of growth in primary culture, the total number of melanocytes in the epidermal cultures decreased to 10% of the number present in normal skin. Beginning on day 2 of culture, bipolar melanocytes were present at a mean cell density of 116 +/- 2/mm2; the keratinocyte to melanocyte ratio was preserved during further primary culture and through three subpassages. Moreover, exposure of cultures to mild UVB irradiation stimulated the melanocytes to proliferate, suggesting that the melanocytes growing in culture maintained their responsiveness to external stimuli. When the sheets of cultured cells were enzymatically detached from the plastic culture flasks before grafting, melanocytes remained in the basal layer of cells as part of the graft applied to the patient. 相似文献
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