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61.
BACKGROUND: The natural history of patients with intraductal carcinoma (DCIS) and microinvasion is poorly defined, and the clinical management of these patients, with particular reference to management of the axilla, has been controversial. Previous studies of this lesion have used varied and/or arbitrary criteria for the evaluation of microinvasion. METHODS: Thirty-eight DCIS lesions with microinvasion (n=29) or probable microinvasion (n=9), diagnosed during the period 1980-1996, were retrospectively analyzed after cases not treated with mastectomy and axillary lymph node dissection were excluded. Microinvasion was defined as a single focus of invasive carcinoma < or = 2 mm or up to 3 foci of invasion, each < or =1 mm in greatest dimension. RESULTS: The patients were all females with a mean age of 56.4 years. DCIS was of comedo (n=31) or papillary (n=7) subtype. Microinvasion was often associated with an altered, desmoplastic stroma (55%) or a lymphocytic infiltrate (39%). The foci of microinvasion ranged from 0.25 to 1.75 mm (mean, 0.6 mm), with an aggregate mean size of 1.1 mm (range, 0.25-2.25 mm). Foci of microinvasion, ranging from 1 to 3 (mean, 1.7), were adjacent to DCIS in 95.3% of cases. The extent of DCIS did not correlate with the number of foci of microinvasion. Axillary lymph node dissections yielded a mean of 19.3 lymph nodes (range, 7-38), and all lymph nodes were negative for metastasis. None of 33 patients, followed for a mean of 7.5 years (range, 1.0-14.4 years), developed local recurrence or metastasis. CONCLUSIONS: The cases of microinvasive carcinoma examined in this study, as defined above, were not associated with axillary lymph node metastases and appeared to be associated with an excellent prognosis. Further study is indicated to determine the appropriate management and long term prognosis of patients with this lesion.  相似文献   
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Research has shown that offspring of depressed caregivers are at increased risk for maladaptive development and emotional difficulties. Specifically, infants and toddlers of depressed mothers have been shown to evidence higher percentages of insecure attachments and more behavioral difficulties than offspring of nondisordered mothers. However, even in studies that reveal significant differences between children of depressed and nondepressed caregivers, a substantial number of children with depressed caregivers do not evidence dysfunction. Such findings have resulted in increased attention to the broader social context in which children of depressed mothers develop. This investigation examined the direct influences of maternal depression on child development, as well as the role of contextual risks that may be particularly heightened in families with depressed parents. Toddlers with depressed mothers evidenced significantly more insecure attachments than did toddlers with nondisordered mothers, and this difference was not accounted for by contextual risk. In predicting child behavior problems, contextual risk was found to mediate the relation between maternal depression and child behavior problems. Father-report data on child behavior corroborated the mother report data. Results are discussed in terms of the diversity of functioning in offspring of depressed caregivers that can be attributed to varied levels of contextual risk accompanying depression.  相似文献   
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Progressive systemic sclerosis may be associated with focal myocardial fibrosis. Electrocardiographic abnormalities including conduction block are common in progressive systemic sclerosis but whether they are due to direct destruction of the specialized conduction tissue of the heart is uncertain. The conduction systems of 35 patients with progressive systemic sclerosis were studied. Of these 35 patients, 17 (50 per cent) had myocardial fibrosis of the type seen in progressive systemic sclerosis. In 10 of the 17, it was severe. Sinus node fibrosis was present in 13 patients and was nearly as frequent in those with as in those without the progressive systemic sclerosis myocardial lesion. Overlying pericarditis may have contributed to the fibrotic changes within the sinoatrial nodes in seven of the 13 patients. The atrioventricular node and main His bundles were normal. However, fibrotic changes were found in the proximal bundle systems in six patients. In three of the six, severe myocardial progressive systemic sclerosis was present, two had focal fibrous atrophy of the left bundle, and one had complete interruption of the right bundle. In only the latter patient was this reflected in the electrocardiogram which showed a right bundle branch block. Three patients without progressive systemic sclerosis myocardial lesions also had fibrous atrophy of a portion of the proximal left bundle branch, and in one the electrocardiogram showed an isolated left anterior hemiblock. Thus, morphologic abnormalities within the conduction system in our patients are difficult to attribute to progressive systemic sclerosis per se. Furthermore, although conduction abnormalities were more frequent in patients with myocardial disease, specific conduction system disease was not the cause in most patients. As has been noted in ischemic heart disease, the conduction system appears to be relatively spared from the myocardial changes of progressive systemic sclerosis, and the high incidence of conduction disturbances in this condition may be a consequence, rather, of damage to working myocardium.  相似文献   
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We measured the effect of a common baby food, strained pears, on the absorption of iron from human milk. Five adult subjects were initially fed 1 dL of human milk that contained added ferrous citrate Fe 59; the same subjects were later fed human milk and one jar of baby food. Incorporation of 59Fe into RBCs averaged approximately one quarter of the administered iron from the human milk. When the milk was combined with the baby food, incorporation was significantly decreased. The addition of a supplemental food to the diet of the breast-fed infant impairs the bioavailability of the iron from human milk.  相似文献   
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The design and performance of a self-contained microprocessor-based gamma-ray spectrometer for use in geophysical measurements using nuclear techniques is described. The instrument uses single-channel analyzers which are inherently simpler and faster than the Wilkinson or successive approximation ADC. A novel technique of gain stabilization together with a simple means of energy calibration has been developed. The modular design of the equipment makes it suitable for multidetector usage, required in a number of nucleonic gauges for the quantitative measurement of chemical constituents.  相似文献   
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