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121.
Gorno-Tempini ML Pradelli S Serafini M Pagnoni G Baraldi P Porro C Nicoletti R Umità C Nichelli P 《NeuroImage》2001,14(2):465-473
Considerable evidence indicates that processing facial expression involves both subcortical (amygdala and basal ganglia) and cortical (occipito-temporal, orbitofrontal, and prefrontal cortex) structures. However, the specificity of these regions for single types of emotions and for the cognitive demands of expression processing, is still unclear. This functional magnetic resonance imaging (fMRI) study investigated the neural correlates of incidental and explicit processing of the emotional content of faces expressing either disgust or happiness. Subjects were examined while they were viewing neutral, disgusted, or happy faces. The incidental task required subjects to decide about face gender, the explicit task to decide about face expression. In the control task subjects were requested to detect a white square in a greyscale mosaic stimulus. Results showed that the left inferior frontal cortex and the bilateral occipito-temporal junction responded equally to all face conditions. Several cortical and subcortical regions were modulated by task type, and by facial expression. Right neostriatum and left amygdala were activated when subjects made explicit judgements of disgust, bilateral orbitofrontal cortex when they made judgement of happiness, and right frontal and insular cortex when they made judgements about any emotion. 相似文献
122.
BACKGROUND: Inhaled beta(2)-agonists are widely used in asthma treatment. The design limitations of pressurized metered dose inhalers (pMDIs) have prompted the development of dry powder inhalers (DPIs) for the delivery of asthma medications. OBJECTIVE: The goal of this study was to evaluate the efficacy, tolerability, and effect on asthma-related quality of life (QOL) of a long-acting beta(2)-adrenoreceptor agonist, formoterol, delivered via multidose DPI, compared with albuterol delivered via pMDI or placebo in adolescents and adults with persistent asthma. METHODS: This multicenter, randomized, double-blind, double-dummy, placebo-controlled, parallel-group study was conducted in outpatient clinics at 18 US centers. Adolescents and adults with persistent asthma received formoterol 10 pg BID via multidose DPI, albuterol 180 microg QID via pMDI, or placebo for 12 weeks. The primary efficacy variable was the 12-hour AUC of forced expiratory volume in 1 second (FEV(1)) after 12 weeks treatment. Secondary efficacy variables included asthma-related QOL, asthma symptom scores, rescue medication use, and other pulmonary function measures. RESULTS: A total of 239 patients (147 females, 92 males; age range, 13-85 years) with persistent asthma were enrolled (formoterol, n = 80; albuterol, n = 79; placebo, n = 80). Formoterol delivered via the multidose DPI resulted in clinically relevant and statistically significant increases in 12-hour AUC of FEV(1) after 12 weeks of treatment compared with albuterol pMDI and placebo (P < 0.019 and P < 0.001, respectively). Asthma-related QOL (total score) was significantly improved with formoterol treatment compared with placebo (P < 0.015). Nocturnal asthma symptom scores significantly improved with formoterol compared with albuterol and placebo (P < 0.001 and P < 0.003, respectively) and rescue medication use was significantly less with formoterol compared with albuterol and placebo (P < 0.004 and P < 0.002, respectively). Treatment with formoterol was well tolerated. CONCLUSIONS: In this study of adolescents and adults with persistent asthma, 12 weeks of treatment with formoterol 10 microg BID delivered via a multidose DPI provided significantly greater 24-hour bronchodilation compared with albuterol and placebo and resulted in significant improvements in asthma-related QOL compared with placebo. Formoterol was well tolerated in these patients. 相似文献
123.
124.
BACKGROUND: Antibiotic combinations are frequently used in order to obtain wide-spectrum effects in the treatment of serious infections such as septicemia and endocarditis, and also to produce an in vivo effect against strains which are defined as resistant to the known inhibiting or fatal dose of one antibiotic. The synergistic effects of combinations such as aminoglycoside + beta-lactam, aminoglycoside + quinolone and quinolone + beta-lactam on Pseudomonas aeruginosa have been revealed in different studies. The multiple resistance rate of nosocomial P. aeruginosa strains isolated from intensive care units (ICUs) has been reported as high in many studies. METHODS: In this study, the effects of various combinations of antibiotics (aminoglycoside + beta-lactam and aminoglycoside + quinolone) against 101 multiresistant P. aeruginosa strains which were isolated from the ICUs of three different hospitals in Istanbul were investigated using the E-test method. The combinations for which the highest synergistic effects were determined by the E-test method were also tested with the checkerboard method, i.e. in addition to the E-test method, in 19 of a total of 23 strains. RESULTS: When the synergistic results which were obtained with the combinations of aminoglycoside + beta-lactam were compared with those of the aminoglycoside + quinolone combinations, they were determined to be higher for the two aminoglycosides gentamicin (GM) and tobramycin (TM). We determined the synergistic rates to be 23, 21, 19, 18, 16, 14, 10 and 10% for GM + ceftriaxone (TX), GM + piperacillin (PP), GM + ceftazidime (TZ), TM + PP, TM + TX, TM + TZ, GM + ciprofloxacin (CI) and TM + CI, respectively. The GM + TX combination - for which the highest synergistic effects were determined with the E-test stripes - was also determined as synergistic with the checkerboard method in 19 of a total of 23 strains (23%), and the agreement rate between the two methods was 100% (kappa > 0.7). The highest synergistic effects against strains which were sensitive to both of the antibiotics which constitute the combinations were found for the GM + TX combination, as 50%, whereas for strains which were resistant to both of the antibiotics, this was found for the TM + PP combination, also as 50%. CONCLUSIONS: We consider that the minimal inhibitory concentration values of antibiotics are not sufficient alone in order to constitute a combination for multiresistant strains and it would be advisable to begin a treatment by applying a combination study. The E-test method has been evaluated as a good alternative for combination investigations because of its ease both of application and evaluation and also for its good agreement with the standard checkerboard method. 相似文献
125.
126.
In this article, we aimed to reduce the effects of geometric errors and measurement noise on the inverse problem of Electrocardiography
(ECG) solutions. We used the Kalman filter to solve the inverse problem in terms of epicardial potential distributions. The
geometric errors were introduced into the problem via wrong determination of the size and location of the heart in simulations.
An error model, which is called the enhanced error model (EEM), was modified to be used in inverse problem of ECG to compensate
for the geometric errors. In this model, the geometric errors are modeled as additive Gaussian noise and their noise variance
is added to the measurement noise variance. The Kalman filter method includes a process noise component, whose variance should
also be estimated along with the measurement noise. To estimate these two noise variances, two different algorithms were used:
(1) an algorithm based on residuals, (2) expectation maximization algorithm. The results showed that it is important to use
the correct noise variances to obtain accurate results. The geometric errors, if ignored in the inverse solution procedure,
yielded incorrect epicardial potential distributions. However, even with a noise model as simple as the EEM, the solutions
could be significantly improved. 相似文献
127.
基于Excel工作表与宏,建立包含公式的酸碱平衡体系模板,计算滴定过程中的酸度变化,绘制滴定曲线,判断滴定突跃,整个过程简便直观。该方法可修改参数,求解未知量(如酸度、物料浓度与体积、酸常数、缓冲容量等),同时由于没有计算公式的简化,计算结果更为准确。 相似文献
128.
Zeynep Eyileten Ahmet Ruchan Akar Sadik Eryilmaz Mustafa Sirlak Levent Yazicioglu Serkan Durdu Adnan Uysalel Umit Ozyurda 《Surgery today》2009,39(11):947-954
Purpose
To assess the results of bilateral pectoralis major muscle flaps (BPMMF) and vacuum-assisted closure (VAC) at different stages of postcardiac surgery mediastinitis. 相似文献129.
Umit Dundar Vural Kavuncu Ihsan H. Ciftci Deniz Evcik Ozlem Solak Tuncay Cakir 《Journal of bone and mineral metabolism》2009,27(4):464-470
There is much evidence suggesting that the decline in ovarian function after menopause is associated with spontaneous increases
in proinflammatory cytokines. Treatment with risedronate is accompanied by significant changes in bone turnover and bone mineral
density. The objective of this study was to determine the effects of risedronate treatment on the level of serum cytokines
including receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin among postmenopausal women with osteoporosis.
The study group consisted of 61 postmenopausal women with osteoporosis. Patients were randomly divided in two groups: In group
1 (n = 41) postmenopausal women received oral risedronate (35 mg/week), calcium (1,000 mg/day), and vitamin D (400 IU/day) for
12 months. In group 2 (control group; n = 20) patients received only oral calcium (1,000 mg/day) and vitamin D (400 IU/day). Bone mineral density (BMD) of lumbar
spine (L1–L4) and proximal femur were determined using dual X-ray absorptiometry at baseline and after one year. Venous blood
samples were obtained for determination of serum cytokines including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α),
RANKL, osteoprotegerin, and markers of bone formation and resorption. Levels of serum cytokines were measured before therapy
and after three and 6 months. Markers of bone metabolism were studied before therapy and after 6 months. In group 1 (risedronate
plus calcium/vitamin D-treated patients), serum levels of RANKL and IL-1β significantly decreased and the level of osteoprotegerin
significantly increased after three and 6 months, but no significant difference was found in TNF-α level. In group 2, however,
the level of serum cytokines did not change after three and 6 months. In cases of bone turnover, both markers of bone resorption
and formation significantly decreased after 6 months in group 1. In conclusion risedronate could improve osteoporosis by increasing
osteoprotegerin and reducing RANKL and IL-1β. 相似文献
130.
Abstract In the presence of multiple concomitant occlusive and aneurysmal diseases, selection of the brain protection method is a primary concern. A case with a disease triad of stenotic lesions in internal carotid arteries, coronary artery atherosclerosis, and an ascending-arcus aorta aneurysm is presented. We simultaneously performed right carotid endarterectomy, coronary artery bypass grafting, and graft replacement of the ascending-arcus aorta. Brain protection was achieved with continuous right brachial artery antegrade selective cerebral perfusion under moderate hypothermia, following carotid endarterectomy. The operative technique is detailed and antegrade selective cerebral perfusion following the carotid endarterectomy for aneurysmal surgery is discussed. 相似文献