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941.
Summary In a review of the vertebral angiograms of 300 patients free from disease at the craniovertebral junction, we found atlantoaxial arterial anomalies in 2,3%. These were: 2 cases in which the vertebral artery ran in the spinal canal below C1, 3 cases of duplication of the vertebral artery above and below C1, and 2 cases of origin of the posterior inferior cerebellar artery at C2. Although these arteries ran in the spinal canal between C1 and C2, they never encroached upon the posterior third of the canal. From the survey of another 21 patients having bony abnormalities at the craniovertebral junction, the first type of arterial anomaly described above was seen in 4 patients and associated with failure of segmentation of the embryonic sclerotome such as occipitalization of the atlas or Klippel-Feil syndrome. It is possible to relate the development of these anomalous vessels to malarrangement of the embryonic segmental arteries. Our results indicate that one must be cautious with lateral C1/2 puncture or surgical exposure of the region.  相似文献   
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We experienced two cases with renal cell carcinoma who showed enlargement of the contralateral adrenal gland. In case 1, the enlarged adrenal gland was a non-functioning adrenal adenoma, and in case 2, it was a metastatic adrenal tumor. Non-functioning adrenal adenomas are benign tumors of the adrenal cortex often found incidentally at autopsy or on computed tomography (CT) studies of the upper abdomen. Adrenal adenomas have been reported to occur in 9.5-14% of patients with renal cell carcinoma, while the incidence being 1.5-8.7% in the general population. Since metastases of renal cell carcinoma to the adrenal glands are not uncommon, it is important to distinguish between non-functioning adrenal adenomas and metastatic tumors. Therefore, we studied the incidence of adrenal tumors (including metastatic tumors and benign tumors) in patients with renal cell carcinoma who underwent the abdominal CT study in our hospital. From 1982 to 1989, CT had been performed in 67 patients with renal cell carcinoma. Six adrenal masses were identified with CT in these patients. Three out of the 6 patients probably had metastatic tumors and one of the 3 adrenal masses was pathologically diagnosed as metastatic tumor. The other three masses were benign on pathology and only one of them was pathologically diagnosed as non-functioning adrenal adenoma. The incidence of adrenal adenomas on the CT study was lower than that of previous studies based on autopsy. The reasons of this difference in results between their studies and ours are not clear.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Sex differentials in infant mortality vary widely across nations. Because newborn girls are biologically advantaged in surviving to their first birthday, sex differentials in infant mortality typically arise from genetic factors that result in higher male infant mortality rates. Nonetheless, there are cases where mortality differentials arise from social or behavioral factors reflecting deliberate discrimination by adults in favor of boys over girls, resulting in atypical male to female infant mortality ratios. This cross-national study of 93 developed and developing countries uses such macro-social theories as modernization theory, gender perspectives, human ecology, and sociobiology/evolutionary psychology to predict gender differentials in infant mortality. We find strong evidence for modernization theory, human ecology, and the evolutionary psychology of group process, but mixed evidence for gender perspectives.  相似文献   
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