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81.
Intrahepatic splenosis: imaging features   总被引:1,自引:0,他引:1  
We report a patient who presented with asymptomatic focal liver lesions and in whom a diagnosis of intrahepatic splenosis was made. This rare condition mostly occurs in patients who previously underwent splenic trauma or surgery. Magnetic resonance imaging (MRI) characteristics suggesting this diagnosis are described. The lesions were mainly hypointense on T1- and hyperintense on T2-weighted images. After administration of small iron oxide particles (SPIO-Endorem), the lesions remained slightly hyperintense relative to the hypointense liver parenchyma but showed a 50% loss in signal intensity. Knowledge of these MRI characteristics may avoid the use of surgical interventions to arrive at the correct diagnosis of these rare liver lesions. Received: 14 June 1999/Accepted: 14 July 1999  相似文献   
82.
Maternal diabetes induces fetal alterations, resulting in lasting consequences for the glucose tolerance of the offspring over several generations. In our experimental rat model, circulating prolactin, oestradiol, progesterone and corticosterone levels, known to influence insulin secretion and action, are determined in plasma of female adult offspring of mildly and severely diabetic mothers. Prolactin and progesterone levels are equally low in both groups as compared to controls, stressing the involvement of the CNS in the transgeneration effect; oestradiol and corticosterone levels are normal. No correlation is found between these hormonal alterations and the known differences in glucose tolerance.  相似文献   
83.
Two cases of epidermal cyst of the breast, a rare benign condition, were detected during a 3-year period in a mammographic screening programme, from 57 954 screening examinations. It is not uncommon for epidermal cysts to be initially misdiagnosed. The mammographic, ultrasound and histological features are presented. It is recommended that these lesions be resected because they possibly have malignant potential.  相似文献   
84.
The word tracheostomy derived from two greek words meaning ‘I cut the trachea’ has been known for about 3500 yrs. The process has evolved over the years and has undergone revolutionary changes in the methodology, instrumentation and indications. Although tracheostomy is now commonly used the complication rate remains high. In our series it was 48% which is comparable with other series. The purpose of this paper is to discuss the complications of tracheostomy with special attention to their management and prevention.KEY WORDS: Complications, Tracheostomy  相似文献   
85.
Centrilobular emphysema: CT-pathologic correlation   总被引:5,自引:0,他引:5  
Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners.  相似文献   
86.
Metabolic and morphological effects of anoxia were studied in alveolar macrophages obtained by lung lavage from guinea-pigs by means of an original method of cell culture allowing direct contact with air without interposition of liquid medium. After selection by glass adherence, alveolar cells were layered on a porous membrane applied to the surface of a reservoir filled with nutrient medium. Alveolar macrophages were then cultured in gas phase under either aerobic or anaerobic conditions for 24, 48 and 72 h. Cellular adenosine triphosphate (ATP) content, an indicator of cell vitality, significantly decreased by 68 and 88% after 48 and 72 h of exposure to anaerobic environment, respectively. Significant increases in lactate production (68% at 24 h) and in glucose uptake (125% at 24 h), evidence of marked glycolytic activity, occurred before these falls in intracellular ATP and parallel decreases in culture medium pyruvate level (76 and 85% at 48 and 72 h, respectively). The shift of energy metabolism resulted in cell death after 72 h, as noted by morphological degeneration and decreased cellular ATP content. Twenty-four hour re-exposure to normoxic atmosphere showed that recovery was possible when duration of anaerobiosis did not exceed 48 h. This reversibility in anoxic cell injury has been related to plasma membrane integrity. The results of these studies indicate that alveolar macrophage resistance to anaerobiosis is limited as ATP content falls and morphological degeneration occurs after 48 h. This novel approach of anaerobic effects at the cell level should be adaptable to investigations of activity and, in particular, the mechanisms of metabolic activity of antianoxic drugs.  相似文献   
87.
Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed.  相似文献   
88.
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.  相似文献   
89.
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications.  相似文献   
90.
Kinetic of cotrimoxazole was studied in serum, alveolar macrophages and BAL fluid from guinea pigs receiving sulfamethoxazole (SMX, 100 mg/kg) and trimethoprim (TMP, 20 mg/kg). Guinea pigs were killed by cervical dislocation 30 min, 1 h, 3 h, 6 h and 24 h after intraperitoneal injection. Lung lavage was performed to obtain alveolar macrophages and BAL fluid. TMP and SMX levels were assayed using high-performance-liquid chromatography. Highest SMX levels were obtained in serum at 30 min, in BAL fluid at 1 h and in alveolar macrophages at 3 h. Mean SMX/TMP ratios (30 min, 1 h, 3 h) was 26.5 +/- 0.8 in serum, 3.76 +/- 1.8 in BAL fluid and 1.15 +/- 0.02 in alveolar macrophages.  相似文献   
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