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101.
BACKGROUND: Aluminum toxicity is well documented and contamination of milk formulas has been implicated as the source of accumulation in bone and brain tissues. The purpose of the current study was to evaluate the aluminum contents of human milk, cow's milk, and infant formulas. METHODS: Aluminum contents were determined by atomic absorption spectrometry in samples of human milk in the colostrum, intermediate, and mature stages; infant formulas from eight manufacturers; and various types and brands of commercially available cow's milk. RESULTS: Mean aluminum concentration was lowest in human milk (23.4 +/- 9.6 microg/l), and did not differ significantly between colostrum, intermediate-stage and mature-stage milk. Mean aluminum concentration was 70 microg/l in cow's milk, and 226 microg/l in reconstituted infant formulas. Aluminum concentrations in infant formulas differed markedly among manufacturers; concentration in milk from one of the manufacturers was particularly high (mean, 551 microg/l; range, 302-1149 microg/l). These values are for milk reconstituted with aluminum-free water under laboratory conditions; formulas prepared with tap water in the University Hospital's infant-feeding unit had even higher aluminum content. Experiments showed that aluminum concentration in the high-aluminum milk could be reduced by more than 70% at the manufacturing stage, by using low aluminum components. CONCLUSIONS: The results of the present study support the recommendations for infant formula manufacturers to strive to reduce aluminum concentration in their products.  相似文献   
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In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed.  相似文献   
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Michael  AS; Mafee  MF; Valvassori  GE; Tan  WS 《Radiology》1985,154(2):413-419
A retrospective review of the dynamic CT studies performed in our institution on head and neck lesions, excluding the brain, was carried out. Five basic types of density vs. time curves were obtained. Dynamic CT scanning is valuable in the differential diagnosis, management, and followup of such cases; its usefulness as an imaging modality in diagnosis and followup of hemangiomas is stressed.  相似文献   
107.
The authors present 32 cases of renal cell carcinoma with inferior vena cava involvement. Three sub-groups of patients can be distinguished on the basis of the level of this involvement: A (24 patients) with infra-hepatic involvement, B (6 patients) with retro-hepatic involvement and C (2 patients) with supra-hepatic involvement. The surgical tactics and results are analysed for each of these 3 sub-groups. The prognosis is relatively good in sub-group A, but is increasingly less favourable in groups B and C.  相似文献   
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The development and progression of epithelial cancers are the result of an imbalance in signals promoting and inhibiting cellular proliferation and apoptosis. The aim of this study is to evaluate the expression of cell-cycle and apoptosis regulators and correlate them with clinical outcome in the most frequent carcinomas, in order to establish common prognostic biomarkers independent of cancer origin. Using tissue microarrays (TMAs), we have analysed the immuno-expression of Ki-67, Bcl-2, Bax, cyclin D1, cyclin D3, CDK1, CDK2, CDK6, p16, p21, and p27 in a series of 205 carcinomas of the large bowel, breast, lung and prostate (80, 73, 37 and 15 cases, respectively). By univariate analysis, positivity for p27, p16 and Bcl-2 was associated with better overall survival (P<0.0135, P<0.0442 and P<0.0001, respectively). The risk of mortality was 2.3-fold greater in patients without Bcl-2 expression. TMA immunohistochemical analysis identified a subset of epithelial cancers with overlapping alterations in cell-cycle checkpoints, apoptosis regulators and tumour suppressor pathways. We found that in most common epithelial cancers, regardless of origin, Bcl-2 appears to be the key biological factor influencing clinical behaviour.  相似文献   
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