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101.
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Nyberg  DA; Mack  LA; Laing  FC; Jeffrey  RB 《Radiology》1988,167(3):619-622
Endovaginal sonography results were compared with quantitatively determined human chorionic gonadotropin (hCG) levels in 84 women referred for early pregnancy complications. Of the 27 with normal intrauterine pregnancies, an intrauterine gestational sac was prospectively identified in one of five cases (20%) in which hCG levels were below 500 IU/L (Second International Standard), four of five (80%) with hCG levels of 500-1,000 IU/L, and all 17 with hCG levels above 1,000 IU/L. In comparison, 17 of the 26 women with ectopic pregnancies (65%) had hCG levels greater than 1,000 IU/L, and none of the 26 had an intrauterine gestational sac. Endovaginal sonography demonstrated an adnexal mass and/or a gestational sac-like structure in 16 of the 17 cases (94%) in which hCG levels were above 1,000 IU/L, compared with only three of the nine (33%) with lower hCG levels (P less than .01). These findings indicate that an intrauterine gestational sac should be normally visualized with endovaginal sonography when the hCG level exceeds 1,000 IU/L, and that visualization of an extrauterine gestational sac and/or adnexal mass is significantly more likely in ectopic pregnancies when the hCG level exceeds 1,000 IU/L.  相似文献   
103.
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas.  相似文献   
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The incidence of HL-A antigens in dermatitis herpetiformis   总被引:2,自引:0,他引:2  
In dermatitis herpetiformis (DH) there are small intestinal abnormalities similar to those in adult coeliac disease (ACD) and there is evidence of other similarities between the two conditions, including immunological disturbances. Two reports of patients with ACD have shown a distinctive distribution of HL-A phenotypes, with a high incidence of HL-Ai and 8. A recent paper has described an increased incidence of HL-A8 in DH. We report a similar study of patients with DH. Twenty-one of thirty-five patients had HL-A8, an incidence of 60%, as compared to 33% of 175 controls. This difference is significant. The relationship of those patients with HL-A8 to those with abnormal jejunal biopsies, and also to those with circulating auto-antibodies, is discussed.  相似文献   
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The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
110.
We have investigated the possible hepatic microsomal enzymeinduction effect of enflurane, administered by inhalation inanaesthetic doses for periods of 1 h a day. In 15 experimentalgroups, differing from one another in anaesthetic concentration(1,2 and 3% enflurane) and in the number of days of treatment(3,7, 10,14,21 and 24) we found (1) no alteration either inthe ratio of liver to body weight or in the microsomal proteincontent; (2) no modifications in aniline hydroxylase activity;(3) a decrease in the aminopynne demethylase activity aftera number of exposures, varying with the dose.  相似文献   
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