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Lasers in Medical Science - Using light sources in phototherapy has presented promising results regarding several types of facial and body skin affections for centuries. The neodymium-doped yttrium...  相似文献   
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The effect of handgrip (HG) isometric exercise on plasma catecholamines, alpha 2-adrenoceptors on platelets and beta 2-adrenoceptors on lymphocytes was studied in normotensive subjects (NT) and essential hypertensive subjects (HT). Whereas systolic blood pressure (SBP) increases were similar in NT and HT subjects, diastolic blood pressure (DBP) and heart rate (HR) increased more in the former group. Baseline values and changes in plasma epinephrine (E) and norepinephrine (NE) did not differ between both groups. No differences were apparent in alpha 2-adrenoceptor density and affinity between NT and HT subjects before or after the test. HG isometric exercise induced a similar increase in beta 2-adrenoceptors on lymphocytes of 22 +/- 7 and 13 +/- 5% in NT and HT subjects, respectively. Affinity to the beta 2-adrenoceptors under baseline conditions was somewhat lower in HT (8.1 +/- 0.4 pM) than in NT subjects (6.5 +/- 0.5 pM), and this difference persisted during the test. Our results indicate that there are no differences in alpha 2- and beta 2-adrenoceptor densities either at baseline conditions or after HG isometric exercise between NT and HT subjects. Small differences noted in affinity to the beta 2-adrenoceptors require further investigation.  相似文献   
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1. alpha 2-Adrenoceptors on platelet membranes and beta 2-adrenoceptors on lymphocytes were studied in 24 patients with primary Raynaud's phenomenon and in 24 age- and sex-matched control subjects. In two subgroups, a standardized mental arithmetic test and a finger-cooling test were performed. 2. Baseline blood pressure, heart rate and forearm blood flow did not differ between the two groups. 3. Baseline skin microcirculation (laser Doppler flux) was decreased in primary Raynaud's phenomenon (19 +/- 15 arbitrary units) compared with control subjects (33 +/- 14 arbitrary units) (P less than 0.01). 4. Baseline plasma noradrenaline concentration (2.00 +/- 1.44 versus 1.16 +/- 0.36 nmol/l) and alpha 2-adrenoceptor density (301 +/- 119 versus 210 +/- 82 fmol/mg) were increased in patients with primary Raynaud's phenomenon in comparison with the control subjects. The alpha 2-adrenoceptor density/beta 2-adrenoceptor density ratio in patients with primary Raynaud's phenomenon was, with a value of 0.37 +/- 0.04, higher than in the control subjects, where a value of 0.25 +/- 0.02 was measured (P less than 0.001). Plasma adrenaline concentration, beta 2-adrenoceptor density and the antagonist affinity to both receptor subtypes did not differ between both groups under baseline conditions. 5. Whereas during the finger-cooling test no differences were seen in the responses of the parameters measured, the mental arithmetic test induced an increase in laser Doppler flux in patients with primary Raynaud's phenomenon and a decrease in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Background  

Pulmonary dysfunction following cardiac surgery is believed to be caused, at least in part, by a lung vascular injury and/or atelectasis following cardiopulmonary bypass (CPB) perfusion and collapse of non-ventilated lungs.  相似文献   
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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   
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