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OBJECTIVE: To investigate the effects of long-term levothyroxine (LT4) suppressive therapy on the heart and the effects of beta-blockade on cardiac functions. DESIGN: Twelve female patients receiving LT4, selected from a group of patients with TSH levels of 0.1-0.4 microU/ml, were evaluated. The control group consisted of 11 healthy subjects and 12 patients with TSH levels <0.05 microU/ml. METHODS: Cardiac evaluation consisted of a 12-lead electrocardiogram and an echocardiographic study. Left ventricular mass index (LVMI), isovolumetric relaxation time (IVR), left ventricular end systolic (LVESD) and diastolic diameters, early (VE) and late (VA) diastolic flow velocities and fractional shortening were evaluated. Exercise capacity was assessed with a bicycle ergometer. Both work load and maximal exercise time were measured. Atenolol was given to the patient group at a dosage of 50 mg/day for 3 months and evaluations were repeated. RESULTS: On basal evaluations, LVMI (96+/-17 vs 78+/-21 g/m(2)) and IVR (101+/-9 vs 91+/-4 ms) were found to be increased in the patients taking LT4 (P<0.01). LVESD was also lower than controls (P<0.05). A decrease in VE and an increase in VA were also observed in the patients (P<0.01). IVR decreased after atenolol (92+/-10 vs 101+/-9 ms, P<0.05). LVMI decreased and VE and VA improved but did not reach statistical significance after beta-blockade. Baseline work load and maximal exercise duration were significantly lower in the patients and improvements were observed after atenolol treatment. CONCLUSIONS: These results indicated that cardiac dysfunction may occur even when TSH is suppressed to 0.1-0.4 microU/ml with LT4. beta-blockade improved the cardiac functions.  相似文献   
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The purpose of this study was to investigate the value of ultrasonographic examination in the diagnosis of Tietze's syndrome and assessment of the changes in costal cartilage following local steroid injection. Nine patients with Tietze's syndrome and 20 normal subjects were studied consecutively. Ultrasound examination was performed using a Sonoline SL Siemens Machine with a linear 5 MHz small parts transducer and ATL Apogee 800 with a 10 MHz linear array transducer. The affected costochondral joint was injected with a combination of 15 mg of triamcinolone hexacetonide and 1 ml of 2% lidocaine. Ultrasound examination was performed following the clinical evaluation and repeated immediately after the injection, then 1 and 4 weeks later. Abnormal echo appearance was detected as an inhomogeneous increase in the echogenicity with intense broad posterior acoustic shadow. Hypoechogenicity and a decrease in the size of costal cartilage were observed 1 week after local steroid injection with absence of the posterior acoustic shadowing. Ultrasonographic examination of costal cartilage is easy and quick to perform. We believe that ultrasound should be the screening procedure of choice for Tietze's syndrome. Local steroid injection proved to be clinically safe and effective in the treatment of patients with Tietze's syndrome.   相似文献   
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European Journal of Nuclear Medicine and Molecular Imaging - The role of radioiodine treatment following total thyroidectomy for differentiated thyroid cancer is changing. The last major revision...  相似文献   
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All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. The screen-printed platforms were modified with multi-walled carbon nanotubes (MWCNTs) to work as a lipophilic solid-contact transducer. The sensing-membrane was plasticized with a suitable solvent mediator and incorporating [NiII(bathophenanthroline)3][CGA]2 complex as a sensory material. In a 30 mM phosphate solution (buffer, pH 6), the sensor revealed a Nernstian-response towards CGA ions with a slope of −55.1 ± 1.1 (r2 = 0.9997) over the linear range 1.0 × 10−7 to 1.0 × 10−3 (0.035–354.31 μg mL−1) with a detection limit 7.0 × 10−8 M (24.8 ng mL−1). It revealed a stable potentiometric response with excellent reproducibility and enhanced selectivity over several common ions. Short-term potential stability and the interfacial sensor capacitance was estimated using both electrochemical-impedance spectroscopy (EIS) and chronopotentiometry techniques. The presented electrochemical platform revealed the merits of design simplicity, ease of miniaturization, good potential-stability, and cost-effectiveness. It is successfully applied to CGA determination in different coffee beans extracts and juice samples. The data obtained were compared with those obtained by liquid chromatography reference method (HPLC).

All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection.  相似文献   
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