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81.
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The effect of a 4-fold increase in alpha1-acid glycoprotein (AGP) on the antiviral efficacy of 5 human immunodeficiency virus (HIV) protease inhibitors (PIs) was examined by the effect of HIV PIs on p24 production in peripheral blood mononuclear cells infected with protease wild-type and PI-resistant HIV isolates. For wild-type virus, the efficacy of the PIs at trough concentrations was unaffected by a 4-fold increase in AGP. With the partially HIV PI-resistant isolate, a 4-fold increase in AGP resulted in 2%, 30%, 37%, 37%, and 42% loss of activity for indinavir, saquinavir, nelfinavir, ritonavir, and amprenavir, respectively. The high-level HIV PI-resistant isolate had a greater loss in activity. The change in IC50 secondary to the addition of AGP was the greatest for ritonavir, nelfinavir, and amprenavir and lowest for indinavir. These data suggest that the target plasma concentration for the highly bound HIV PIs may need to be raised in subjects with elevated AGP who harbor partially PI-resistant isolates.  相似文献   
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Cardiac myxoma (CM) is by far the most common primary benign cardiac tumor, typically arising in the left atrium with an attachment point in the fossa ovalis region. Although the etiology of CM remains unclear, we know that this endocardial-based mass originates from undifferentiated mesenchymal cells. Continuous technical improvements in the field of echocardiography since the 1960s has profoundly changed the diagnostic approach by allowing a good tumor detection as well as the preoperative planning by providing crucial information concerning the attachment point location. However, echocardiography has its limitations among which lack of tissue characterization and restricted field of view can arise diagnosis difficulties in atypical presentations. With the widespread and routine use of echocardiography and chest computed tomography (CT), incidental detection of CM is not infrequent. As a consequence, it has become mandatory for cardiologists and radiologists evolving in a multimodality imaging world to be familiar with the wide range of presentations of this tumor. The authors present here a review of the common and less common aspects of CM using the main imaging modalities available: echocardiography, cardiovascular magnetic resonance imaging, CT, positron emission tomography and coronary angiography.  相似文献   
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Primary hypertrophic osteoarthropathy   总被引:18,自引:0,他引:18  
We describe seven patients with primary HOA and review 125 cases reported in the English, French, and German literature. The salient clinical features of primary HOA are: a bimodal distribution of disease onset with one peak during the first year of life and the other at age 15, a male predominance (nine to one), uncommon benign joint effusion, and a variety of skin abnormalities resulting from cutaneous hypertrophy or glandular dysfunction. We concluded that HOA is not a synovial disease. It is suggested that synovial effusions, when present, are perhaps a sympathetic reaction to the neighboring periostitis. Proposed diagnostic criteria for HOA, including digital clubbing and radiographic periostitis, appear 86% sensitive. The clinical features, age of onset, and sex distribution suggest that a genetically controlled growth promoting factor, different from growth hormone, plays a role in the pathogenesis of this syndrome.  相似文献   
85.
Pelvic lymphadenectomy is widely accepted as an essential part of radical cystectomy. It provides important information (number of lymph nodes involved, tumor volume, capsular perforation) for prognosis, which may help identify patients at increased risk for progression. More important, there is a growing body of evidence indicating that meticulous, extended pelvic lymphadenectomy may cure a substantial number of patients who would otherwise develop local recurrences or distant metastases. Furthermore, extended bilateral lymph node dissection facilitates cystectomy, makes it safer to perform and does not substantially alter morbidity of the operation.  相似文献   
86.
A cross-sectional survey of 102 Peace Corps volunteers in Niger, West Africa, in 1998 had previously demonstrated a high rate of thyroid dysfunction and goiter attributable to excess iodine from their water filters. The Peace Corps volunteers were followed-up a mean of 30 wk after they ceased using iodine-based water filtration systems. Goiter was present in 44% of subjects during excess iodine ingestion and in 30% after removal of excess iodine. Mean serum iodine decreased from 293 micro g/liter during excess iodine ingestion to 84 micro g/liter after cessation of excess iodine. Mean total serum T(4) values increased from 100.4 to 113.3 nmol/liter (7.8 to 8.8 micro g/dl). Mean serum free T(4) increased from 32.2 to 34.7 pmol/liter (2.5 to 2.7 ng/dl). Mean serum TSH decreased from 4.9 to 1.8 mU/liter. Mean serum thyroid peroxidase antibody levels decreased from 33,000 to 22,000 IU/liter (33 to 22 IU/ml). We found that during prolonged excess iodine exposure there were marked increases in serum total iodine concentrations, and the prevalence of goiter, elevated serum TSH values, and elevated serum thyroid peroxidase antibody values increased. The prevalence of all abnormalities decreased after removal of excess iodine from the drinking water system.  相似文献   
87.

Objective

To examine how cardiorespiratory fitness and self-perceived stress are associated with burnout and depression. To determine if any relationship between stress and burnout/depression is mitigated among participants with high fitness levels.

Methods

197 participants (51% men, mean age = 39.2 years) took part in the study. The Åstrand bicycle test was used to assess cardorespiratory fitness. Burnout was measured with the Shirom–Melamed Burnout Questionnaire (SMBQ), depressive symptoms with the Hospital Anxiety and Depression Scale (HAD-D). A gender-matched stratified sample was used to ensure that participants with varying stress levels were equally represented.

Results

Participants with moderate and high fitness reported fewer symptoms of burnout and depression than participants with low fitness. Individuals with high stress who also had moderate or high fitness levels reported lower scores on the SMBQ Tension subscale and the HAD-D than individuals with high stress, but low fitness levels.

Conclusion

Better cardiovascular fitness seems to be associated with decreased symptoms of burnout and a better capacity to cope with stress.

Practical implications

Promoting and measuring cardiorespiratory fitness can motivate employees to adopt a more physically active lifestyle and thus strengthen their ability to cope with stress exposure and stress-related disorders.  相似文献   
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