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101.
Findings of CT of the spleen were compared with those of histologic examination in 35 patients who had Hodgkin disease. CT provides a simple way to calculate splenic size. This index is also of value in the assessment of the histologic state of the spleen. An accuracy rate of 91%, specificity of 94%, and a sensitivity of 89% in diagnosing splenic localization of lymphoma was found in this study.  相似文献   
102.
Magnetic resonance (MR) imaging, proton MR spectroscopy, and biochemical analysis were performed to investigate MR signal intensity (SI) differences between concentrated and dilute gallbladder bile of seven fasting and five sincalide-treated dogs. MR images revealed high SI from bile of fasting dogs and low to medium SI in sincalide-treated dogs when spin-echo (SE) pulse sequences with repetition rates of 0.5 and 2.0 sec were used. Proton MR spectra were similar for fasting and sincalide-treated dogs. In fasting dogs, water content in the bile was slightly lower, and cholesterol, phospholipid, and bile acid concentrations were higher. More than 90% of proton signals in all Fourier transform free induction decay spectra emanated from water molecules, and no lipid proton resonances were detected in Fourier transform SE spectra after tau delays of 7 msec. These results indicate that the differences in SI are caused by alterations in relaxation times of water protons, possibly resulting from the interactions of water protons and macromolecules.  相似文献   
103.
Uterine MR imaging: effects of hormonal stimulation   总被引:2,自引:0,他引:2  
Demas  BE; Hricak  H; Jaffe  RB 《Radiology》1986,159(1):123-126
Magnetic resonance (MR) imaging characteristics of the uterine corpus were evaluated in 40 women divided into five physiologic categories (nine premenarchal, 13 reproductive age not taking hormones, seven reproductive age taking oral contraceptives, six reproductive age taking gonadotropin releasing hormone analog, and five postmenopausal). Images were generated using a 0.35-T magnet and a double spin-echo technique. On both T1-weighted and T2-weighted images, premenarchal and postmenopausal uteri were small and relatively featureless. Uteri on T2-weighted images in reproductive age women not taking exogenous hormones showed variations in endometrial and myometrial width, signal intensity, and T1 and T2 values during the menstrual cycle. Oral contraceptives and gonadotropin releasing hormone analogs caused endometrial atrophy and alterations in myometrial signal intensity and T1 and T2 values. A detailed gynecologic history is therefore essential in the evaluation of uterine anatomy in patients undergoing pelvic MR imaging.  相似文献   
104.

Background  

Dental assistants help the dentist in preparing material for filling teeth. Amalgam was the filling material mostly commonly used in Norway before 1980, and declined to about 5% of all fillings in 2005. Amalgam is usually an alloy of silver, copper, tin and mercury. Copper amalgam, giving particularly high exposure to mercury was used in Norway until 1994. Metallic mercury is neurotoxic. Few studies of the health of dental assistants exist, despite their exposure to mercury. There are questions about the existence of possible chronic neurological symptoms today within this working group, due to this exposure. The aim of this study was to compare the occurrence of neurological symptoms among dental assistants likely to be exposed to mercury from work with dental filling material, compared to similar health personnel with no such exposure.  相似文献   
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The intravertebral vacuum cleft: a sign of ischemic vertebral collapse   总被引:14,自引:0,他引:14  
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Mixed liver cell spheroids from rats consisting of hepatocytes and nonparenchymal cells lose three-dimensional structure and function when cultured on dishes. In order to maintain the configuration and function of the spheroids, we cultured them with collagen gel in various conditions, such as on the surface of collagen gel (group 2), between two collagen gel layers (group 3), and within collagen gel (group 4). Spheroids cultured on a standard collagen-coated dish were used as controls (group 1). Culture was continued for 10 days. Phase-contrast microscopy revealed that the spheroids of group 1 lost their spheroidal configuration and became a monolayer within 24 h. Group 2 spheroids also spread out to a monolayer, but thus occurred at 24 to 48h. In group 3, spheroid configuration was sustained until day 10, though slightly flattened. In group 4, the spheroid configuration was well maintained throughout the culture period. Urea synthesis of the spheroids cultured with collagen gel was significantly higher than in group 1 between days 1 and 3. Albumin synthesis of three experimental groups was also significantly higher than that of group 1. Although three experimental groups showed no difference in urea synthesis, albumin production by spheroids in groups 3 and 4 was better maintained than in group 2, even toward the end of the culture period. It is concluded that mixed liver-cell spheroid culture within collagen gels showed better maintenance of their configuration and function.  相似文献   
110.
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