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The activity of a rheumatic disease can be influenced by pregnancy and puerperium. Prospective studies have shown an improvement in joint involvement in rheumatoid arthritis in two thirds to three quarters of pregnancies. After birth, an exacerbation is common. In spondylarthropathies there is no relevant change in disease activity. The fetal outcome is not impaired in patients with rheumatoid arthritis and inflammatory spondylarthropathies. Every pregnancy in women with a rheumatic disease should be considered as high-risk, and such pregnancies require close collaboration between rheumatologists and obstetricians. 相似文献
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The planum temporale is a triangular region on the upper surface of the temporal lobe. This area of the brain is important for language processing and shows a left-right asymmetry of size in most brains. Particular interest has been focused on the size and asymmetry of the planum temporale in brains of individuals with developmental dyslexia. Magnetic resonance imaging (MRI) is a method that produces excellent morphological details of organic structures. We have developed an MRI method of studying the size and asymmetry of the planum temporale in human brains. Because of considerable variation of anatomical landmarks in this cortical region of the brain, an evaluation of asymmetry is not possible in all brains. Furthermore, our experience with this method indicates that any indirect imaging technique of studying asymmetry of the planum temporale must be evaluated with caution. With this in mind, however, MRI may give valuable anatomical information about the planum temporale in individuals with anomalous language function. 相似文献
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Muscle cell leakage due to long distance training 总被引:3,自引:0,他引:3
K. NØrregaard Hansen J. Bjerre-Knudsen U. Brodthagen R. Jordal P. -E. Paulev 《European journal of applied physiology》1982,48(2):177-188
Summary Abnormal myoglobinemia (above 77 g/1) and free hemoglobin in plasma were found in 16 runners and in nine non runners immediately following distance running. The same abnormalities were found in six elite rowers following rowing. In parallel with the rise in myoglobin and free hemoglobin a rise was found in serum concentrations of cellular enzymes (LDH, CK, ASAT, alkaline phosphatase) and of various metabolites. We found no proteinuria nor casts in the urine. Non runners had a higher rise in serum myoglobin than runners. Competitive running caused a rise in the serum concentration of the heart specific fraction of creatine kinase in seven of the nine (healthy) elite runners. The abnormal findings are only explainable on the basis of leakage of proteins from muscle cells to the circulation in otherwise healthy, well trained persons. Myoglobinemia and a transient rhabdomyolysis is a common phenomenon in long distance running, but evidently also occurs in distance rowing. Three months of running training prevented most of the muscle damage from relaxed jogging in the nine previous non runners. Neither the observed myoglobinemia nor the hemoglobinemia resulted in any significant loss of iron in the urine.Supported by IdrÆttens Forskningsråd, Dansk IdrÆtsforbund 相似文献
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Summary Major changes occur in the serum level of several hormones during 5 days of heavy and continuous physical activities, with less than a total of 2 h of sleep. The present investigation was designed to evaluate the importance of caloric deficiency, energy requirement being about 8,000–10,000 kcal/24 h. A comparison between well fed subjects and those with food deprivation revealed significantly higher levels of (T3) triiodothyronin, insulin and thyroid stimulating hormone (TSH) in the well-fed subjects, who also had lower levels of growth hormone (hGH) and cortisol, whereas no difference was found between the two groups for thyroxin (T4). Increased levels were found for T3 and T4 in both groups during the first day of activity, with a concomitant decrease in TSH and a subsequent decrease of T4 during the next 2 days. T3 decreased only in the low-calory group whereas increased levels were found in the iso-calory group throughout the course. The resting levels of insulin decreased during the course in the low-calory group whereas it increased in the iso-calory group. High levels were maintained throughout the course for hGH. Cortisol showed high levels just before the start of the course and then decreased from day 2 to day 4. No difference was found between the morning and evening levels for cortisol, indicating disappearance of the circadian rhythm. The present investigation has shown that energy deficiency during prolonged physical strain is responsible for the decreased serum levels of T3 and insulin and may contribute to the decrease in TSH and the increase in hGH and cortisol. 相似文献
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Novel mouse model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis 下载免费PDF全文
Hoffmann N Rasmussen TB Jensen PØ Stub C Hentzer M Molin S Ciofu O Givskov M Johansen HK Høiby N 《Infection and immunity》2005,73(4):2504-2514
Pseudomonas aeruginosa causes a chronic infection in the lungs of cystic fibrosis (CF) patients by establishing an alginate-containing biofilm. The infection has been studied in several animal models; however, most of the models required artificial embedding of the bacteria. We present here a new pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF mice (Cftr(tmlUnc-/-)) and BALB/c mice, as reflected by the detection of a high number of P. aeruginosa organisms in the lung homogenates at 7 days postinfection and alginate biofilms, surrounded by polymorphonuclear leukocytes in the alveoli. In comparison, both an AHL-producing nonmucoid revertant (NH57388C) from the mucoid isolate (NH57388A) and a nonmucoid isolate (NH57388B) deficient in AHL were almost cleared from the lungs of the mice. This model, in which P. aeruginosa is protected against the defense system of the lung by alginate, is similar to the clinical situation. Therefore, the mouse model provides an improved method for evaluating the interaction between mucoid P. aeruginosa, the host, and antibacterial therapy. 相似文献
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P. Magnus A. -L. BØrresen P. K. Opstad J. F. Bugge K. Berg 《European journal of applied physiology》1984,53(1):21-24
Summary Effects of four days of intense physical activity on serum concentrations of total triglycerides, total cholesterol and apolipoproteins A-I, A-II, and B were studied in 35 well-trained young men. Serum total triglyceride levels decreased to 70% of baseline levels after 24 h, and fell further to 50% of baseline levels after 4 days. Serum levels of total cholesterol fell steadily to about 80% of baseline levels on the 4th day. Apo-B levels fell to 85% of baseline levels after 24 h, and remained at that level. Apo A-I fell to about 90%, and apo A-II to about 80% of baseline levels, causing a significant increase in the ratio of apo A-I to apo A-II. The intraindividual changes in apo B were positively correlated to changes in cholesterol during the first day (r=0.60). The changes in apo A-I and apo A-II had no significant correlation with changes in total cholesterol or triglycerides, or with one another, suggesting that apo A-I and apo A-II are metabolized independently during conditions of hard physical exercise. 相似文献