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101.
Zusammenfassung Anamnese und Diagnostik: Ein 75-jähriger Patient wies neben unspezifischen anamnestischen Symptomen (Appetitverlust, Merkfähigkeitsstörung und Muskelschwäche) klinisch diskrete Beinödeme, abgeschwächte Muskeleigenreflexe und eine deutliche Gedächtnisstörung auf. Aufgrund einer euvolämischen, laborchemisch hypoosmolaren Hypoatriämie und eines Urinnatriums im Normbereich wurde als Arbeitsdiagnose von einem Syndrom der inadäquaten ADH-Sekretion (SIADH) ausgegangen. Während sich weder in der Anamnese noch in den folgenden Untersuchungen eine dem SIADH zugrunde liegende Pathologie eruieren ließ, ergab sich in den weiteren Laboruntersuchungen der Befund einer ausgeprägten Hypothyreose. Die Hyponatriämie bei Hypothyreose spiegelt eine Komponente der renalen Funktionsstörung bei Schilddrüsenhormonmangel wider. Therapie und Verlauf: Nach Flüssigkeitsrestriktion und Hormonsubstitution erreichte der Patient schnell normale Natriumwerte und zeigte eine deutliche Besserung seiner kognitiven Fähigkeiten. Schlussfolgerung: Als Schlussfolgerung aus dieser Kasuistik wird Zurückhaltung bei der Diagnose eines SIADH empfohlen, bevor nicht eine sorgfältige Untersuchung des Nebennieren- und Schilddrüsenhormonstatus erfolgt ist. Abstract Case History and Diagnosis: A 75-year-old male patient presented with a history of anorexia, muscle weakness, and increasing memory loss. He had mild pedal edema and decreased deep tendon reflexes. As the laboratory tests showed hypoosmolar hyponatremia and urinary sodium within the normal range, a syndrome of inappropriate ADH secretion (SIADH) was presumed. While neither the medical history nor any of the diagnostic procedures revealed any underlying pathology explaining the SIADH, laboratory tests showed significant hypothyroidism. Hypothyroid states are associated with significant changes in renal function, one of which is hypoosmolar hyponatremia. Treatment and Course: Treatment included fluid restriction and hormone substitution and resulted in a quick correction of the hyponatremia and a clear improvement of the patient's cognitive function. Conclusion: It is concluded that the diagnosis of SIADH should only be made after thorough investigation of the adrenal and thyroid hormone status.  相似文献   
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Summary:  Purpose: Psychogenic nonepileptic seizures (PNES) are episodes that may resemble epileptic seizures (ES) but are not associated with abnormal electrical discharges in the brain. Video-EEG recording of a typical episode is considered the best diagnostic tool available. PNES are, however, also documented in patients with epilepsy (PNES/ES). The purpose of this study was to assess this comorbid population, focusing on the differences between patients with PNES/ES and patients with PNES alone.
Methods: We reviewed 110 PNES episodes, occurring spontaneously or induced by means of suggestion techniques, recorded in our video-EEG laboratory over a period of eight years. We identified two subgroups of patients, consisting of 85 PNES cases and 25 PNES/ES cases, and assessed any differences in their characteristics by reviewing a number of variables (age, sex, clinical features, antiepileptic therapy, age of onset, time to diagnosis, pathological history, and length of follow-up).
Results: The comparison between the two subgroups revealed that PNES/ES patients displayed some statistically significant differences when compared with PNES alone patients, i.e., younger age, a higher percentage of spontaneously activated events, a shorter disease duration, a longer time to PNES diagnosis, and a lower percentage lost at follow-up.
Conclusions: This study confirms that PNES is a common, though probably underestimated, occurrence in epilepsy services. Our results shed light on some different characteristics between PNES and PNES/ES patients.  相似文献   
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OBJECTIVE: To investigate the association between the use of fluoroquinolone agents and the risk of tendinitis in a large population-based case-control study. METHODS: The study was performed by linking automated health databases from the Region of Lombardia, Italy. Cases were patients aged > or =18 years who had a hospital discharge diagnosis of non-traumatic tendinitis in 2002-3. For each case, up to five controls were randomly selected among those eligible for inclusion in the study. A conditional logistic regression model was used to estimate the odds ratio of tendinitis associated with the current, recent and past use of fluoroquinolones. Odds ratios were adjusted for exposure to other antibacterials and other drugs. RESULTS: 22,194 cases and 104,906 controls met the inclusion criteria. Current use of fluoroquinolones significantly increased the risk of tendon disorders as a whole (odds ratio [OR] = 1.7; 95% CI 1.4, 2.0), tendon rupture (OR = 1.3; 95% CI 1.0, 1.8) and rupture of the Achilles' tendon (OR = 4.1; 95% CI 1.8, 9.6). Concomitant use of corticosteroids and fluoroquinolones increased the risk of both tendon rupture (OR = 3.1; 95% CI 1.5, 6.3) and rupture of the Achilles' tendon (OR = 43.2; 95% CI 5.5, 341.1). DISCUSSION: Evidence that exposure to fluoroquinolones is associated with the sudden occurrence of tendinitis is supported by this large population-based study. We can estimate that a single case of rupture of the Achilles' tendon would occur for every 5958 persons treated with fluoroquinolones (95% CI 2148, 23,085). The corresponding number needed to harm is 979 (95% CI 122, 9172) for patients who concomitantly use corticosteroids and 1638 (95% CI 351, 8843) for those aged >60 years. CONCLUSION: Clinicians should be aware of this adverse effect, and the increased risk for fluoroquinolone-associated tendinitis in elderly patients with corticosteroid use must be considered when these agents are prescribed.  相似文献   
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Semi-interpenetrating networks (semi-IPN's) based on linear poly(phenylene ether)s and crosslinked polystyrene can be prepared by reactive moulding of crosslinkable polymeric mixtures. These materials show thermomechanical properties which strongly depend on both the ratio of the two polymeric matrices and the degree of crosslinking in the polystyrene network. Samples based on a 50/50 weight ratio of poly(2,6-dimethyl-1,4-phenylene oxide)/crosslinked polystyrene show glass transition temperatures (Tg) which are very dependent on the degree of crosslinking. It is therefore possible to obtain materials with desired Tg, ranging from the Tg of the corresponding linear blend to that of poly(2,6-dimethyl-1,4-phenylene oxide) alone.  相似文献   
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Variation in the risk of breast cancer observed among women and among populations may be explained by variation in lifetime exposure to estrogens. The suppressive effect of exercise on estradiol levels in women is well documented, but it is unknown whether habitual (i.e. typical daily) physical activity has a similar effect. Epidemiological data suggest that physical activity is one of the few modifiable factors capable of reducing the risk of breast cancer in women. We investigated whether variation in the amount of habitual activity corresponds to variation in estradiol levels in women of reproductive age. One hundred and thirty-nine regularly menstruating women 24-37 years of age collected daily saliva samples for one complete menstrual cycle and kept a daily log of physical activity. Saliva samples were analyzed for concentration of estradiol. We observed a negative relationship between habitual physical activity and salivary levels of estradiol. Mean estradiol was 21.1 pmol/l in the low, 17.9 pmol/l in the moderate and 16.6 pmol/l in the high activity group (all pairwise differences were statistically significant at P<0.009). A strong association exists between physical activity and levels of estradiol among women of reproductive age. A modern lifestyle, characterized by reduced physical activity, may therefore contribute to a rise in the levels of estradiol produced during menstrual cycles and thus to higher cumulative lifetime exposure to estradiol, resulting in a higher risk of breast cancer.  相似文献   
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OBJECTIVES: The sinuses of Valsalva are known to contribute to the normal function of the aortic valve. Little is known about their role in promoting coronary artery blood flow. The aim of this study was to compare coronary artery flow characteristics among patients undergoing a Bentall operation by means of a conventional cylindrical Dacron conduit or with a new conduit with pseudosinuses of Valsalva or in patients retaining their natural sinuses of Valsalva after aortic valve and supracoronary ascending aorta replacement. METHODS: One year after a Bentall procedure with a standard cylindrical Dacron conduit (7 patients, group A) or with the new conduit (7 patients, group B), or after aortic valve and ascending aortic replacement (control group, 7 patients, group C) coronary flow velocity reserve and diastolic to systolic time integral ratio at baseline and after maximal hyperemia (with 40 microg of adenosine) were assessed by using a 0.014-in. Doppler guidewire positioned in the middle portion of the left anterior descending coronary artery. All patients were in NYHA class I, sinus rhythm and free of coronary disease. RESULTS: Arterial blood pressures and heart rate were comparable among groups. Intracoronary Doppler measurements did not show any significant difference in coronary vascular reserve between the three groups (3.6+/-0.4 vs 3.1+/-0.7 vs 3.7+/-0.5, P = 0.2). A greater diastolic component at baseline was present in group B patients (5.5+/-1.9 vs 3.5+/-0.9 in group A and 3.7+/-0.9 in group C, P = 0.024). After maximal hyperemia the diastolic component increased slightly in group A patients (8%) while both in groups B and C significantly decreased (-15 and -20%, respectively) (P = 0.017). CONCLUSIONS: The presence of pseudosinuses of Valsalva does not influence coronary flow reserve. After maximal coronary vasodilation the increase in the systolic component of coronary flow is more evident in the presence of sinuses or pseudosinuses of Valsalva, thus suggesting that coronary flow pattern may be affected by the presence of sinuses.  相似文献   
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