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51.
We analyzed the CT images (in vivo) of 5 lobes (right middle lobe, 1; left lower lobe, 1; right lower lobe, 3) with panacinar emphysema (PAE) obtained at autopsy or thoracotomy for solitary lung tumor. The lobes were inflation-fixed by the method of Heitzman and sliced axially for a CT-pathologic correlative study. One lobe with mild PAE had normal appearance on CT; however, the other four lobes with PAE demonstrated low-attenuation areas (LAAs) of various shapes and sizes on CT. LAAs were locally distributed on CT slices in one lobe, dominant in the inner zones in two lobes, and diffuse in one lobe. Relatively normal to diminished vasculature was observed within the LAAs of four lobes. These CT findings differed significantly from those of centriacinar emphysema (CAE) as reported in other studies. We conclude that CT is useful in the clinical diagnosis of PAE and its differentiation from CAE.  相似文献   
52.
We report herein the case of a 42-year-old man in whom dyspnea on exertion was found to be caused by isolated tricuspid stenosis. Two-dimensional echocardiogram showed thickening of the tricuspid valve with a markedly enlarged right atrium. A color-flow Doppler examination-revealed severe tricuspid stenosis without regurgitation and a Doppler-derived tricuspid diastolic pressure gradient of 23 mmHg. At the time of surgery, the patient was noted to have a stenotic tricuspid valve with thickened leaflets, fused commissures, and almost normal chorda tendineae. The valve leaflets were teased apart to the scattered specimen, and tricuspid valve replacement was successfully performed. Microscopic examination of the specimen demonstrated infective endocarditis. Isolated acquired tricuspid stenosis is extremely rare and, to our knowledge, this is the first case of infective endocarditis being involved as the primary cause.  相似文献   
53.
The effect of complete unilateral ureteral obstruction (CUUO) on proximal tubular functions was studied in rats, using the K+-sensitive microelectrode technique and split oil drop method. In the control kidneys peritubular membrane potential (EMperi) and intracellular potassium activity (aKi) were -70.8 +/- 7.0 mV and 81.2 +/- 22.0 mEq/liter (mean +/- SD), respectively. In the CUUO kidneys both EMperi and aKi were progressively reduced with the duration of obstruction. However, in all tubules aKi values were still above the electrochemical equilibrium. In the three days' CUUO kidneys EMperi and aKi were -51.5 +/- 11.7 mV and 53.8 +/- 22.8 mEq/liter, respectively. Rate of fluid absorption (JVL;nl./sec. mm.) across the proximal tubular epithelium from Ringer solution in the control and three days' CUUO kidneys was 0.029 and 0.0065 respectively. In the CUUO kidneys there were wide variations in JVL and EMperi, but there was a clear correlation between these two variables. JVL from choline chloride solution was negligible in both control and CUUO kidneys. From above results, it was suggested that the proximal tubular reabsorption primarily depending on the Na+-K+ pump might be reduced but still working in the CUUO kidney, and thus the proximal tubular reabsorption might take part in preservation of glomerular filtration during the obstruction.  相似文献   
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Objective. Tympanic temperature can be obtained instantaneously using an infrared emission detection (IRED) thermometer. Its accuracy has been documented in a variety of clinical settings, but its performance at low body temperatures is still unknown. In this study we evaluated its performance during coronary artery revascularization surgery in which mild hypothermic cardiopulmonary bypass (CPB) was used. Methods. Thirty adult patients undergoing coronary artery bypass graft surgery were enrolled in the study. Tympanic temperature obtained using IRED thermometry (Tt1) was compared with core temperatures from the esophagus (Te), and venous blood of CPB (Tv) before, during, and after CPB. We also measured tympanic temperature using a thermocouple probe (Tt2) in 16 of the 30 patients in order to study the agreement between the two methods. Values for correlation coefficients and limits of agreement were computed to assess the degree of agreement among the temperatures obtained. Results. The highest agreement with Tv during CPB was obtained from Tt1 (r = 0.94, 0.41 ± 1.73, limits of agreement) and from Te (0.91, 0.36 ± 2.46). Tt1 also showed good agreement with Tt2 during surgery. Conclusions. Infrared tympanic thermometry is a reliable, alternative method to measure tympanic temperature and may be useful to assess core temperature in both normothermic and mild hypothermic conditions.  相似文献   
57.
Although occult urinary blood in health examinations is common in healthy employees, in the majority with occult urinary blood usually no further examination or treatment is necessary, but occult urinary blood could be an early symptom in urinary tract malignancy. In this study the data on health examinations of male employees with occult urinary blood were analyzed from 1999 to 2002 and strategies for them were discussed. The subjects were male employees working in a steel company, 1,135 ('99), 1,077 ('00), 994 ('01) and 945 ('02). The positive ratios of occult urinary blood were 8.6% in '99, 7.6% in '00, 7.8% in '01, 8.3% in '02, respectively. Multiple logistic regression analysis showed that age and urinary protein were significant factors associated positively with occult urinary blood. In general, a man who had urinary tract malignancy would have macroscopic hematuria in the course of the disease. Therefore, in people with recurrent occult urinary blood the risk of urinary malignancy is considered to be rare. The follow-up protocol was set up for employees with occult urinary blood. For four years 6 employees were referred to specialists (5 to a urologist and 1 to a nephrologist). No significant disease, including urinary tract malignancy, was detected.  相似文献   
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For the rapid and sensitive detection of p53 gene mutations in esophageal endoscopic biopsy specimens, we combined cell sorting with the polymerase chain reaction and single-strand conformation polymorphism (PCR-SSCP) analysis. Mutations in exons 5–8 of the p53 gene were investigated by FCR-SSCF analysis using 103 sorted nuclei obtained from each endoscopic biopsy specimen of 16 patients with esophageal cancer. DNAs extracted from their respective surgical specimens were investigated by a conventional method of PCR-SSCP analysis. Mutations in the biopsy specimens were detected in 6 of the 12 aneuploid tumors but in none of the 4 diploid tumors. After tumor cell enrichment by cell sorting, one mutation in exon 8 became apparent, which could not be detected from the surgical specimen by a conventional method of PCR-SSCP analysis. This method should improve the sensitivity of detecting p53 gene mutations, and provides additional information concerning the DNA ploidy pattern in the tumors.  相似文献   
60.
Summary: We studied the effect of antiepileptic drugs (AEDs) on internal carotid artery (ICA) blood flow velocity, as an index of total cerebral blood flow (CBF). The subjects were 45 newly diagnosed children with febrile convulsion or epilepsy who were seizure-free for a period long enough not to affect the results. They had no neurologic deficit, received fixed monotherapy, and were examined by a noninvasive Doppler ultrasound method, in comparisonwith 13 age-matched normal volunteers with no AED. In 30 patients, the measurements were performed before and after AED administration [10 with phenobarbital (PB), 10 with carbamazepine (CBZ), and 10 with valproate (VPA)], and performed before and after AED discontinuation in the remaining 15 patients (all with PB). Normal volunteers underwent the two consecutive examinations with a mean interval equal to that of the entire patient group, and there was no difference in velocity values between the measurements. In patients receiving CBZ or VPA, a significant reduction was noted in blood flow velocity after drug administration. Although velocity values in the patients receiving PB did not change after drug administration, they were significantly increased after complete discontinuation. In the present study, a slight but significant reduction in CBF caused by AED administration at therapeutic doses in children was suggested.  相似文献   
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