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11.
Urokinase plasminogen activator (uPA) is a serine protease involved in cancer invasion and metastasis. uPA acts in vivo by binding to a membrane receptor known as uPAR. In this study, uPA and uPAR levels were semiquantitated by immunocytochemistry in 36 primary breast carcinomas. Using monoclonal antibody HD-UK 1, uPA was detected both in stromal and in malignant cells. However, the predominant location was in the stromal cells. Using double-staining, cells containing uPA were also found to coexpress either cytokeratin (an epithelial cell marker) or more frequently KP1 (a macrophage/monocyte cell marker). With monoclonal antibody HD-uPAR 13.1, uPAR was localized principally to spindle- or macrophage-like stromal cells, especially when these cells surrounded invasive breast cancer. In contrast, uPAR was only rarely detected in cancer cells and was not detected in normal epithelia surrounding tumour or in areas of adenosis. uPA levels in both stromal and epithelial cells were significantly correlated with those for uPAR. We conclude that both uPA and its receptor are mostly present in stromal cells in invasive breast carcinomas. These results suggest that stromal cells collaborate with malignant cells to mediate metastasis.  相似文献   
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There is variability in home visiting program impacts on the outcomes achieved by high risk families. An understanding of how effects vary among families is important for refining service targeting and content. The current study assessed whether and how maternal attributes, including relationship security, moderate short- and long-term home visiting impacts on maternal psychosocial functioning. In this multisite RCT of home visiting in a population-based, ethnically-diverse sample of families at risk for maltreatment of their newborns (n?=?643), families were randomly assigned to home visited (HV) and control groups. HV families were to receive intensive services by trained paraprofessionals from birth-3 years. Outcome data were collected when children were 1, 2, and 3 years old and 7, 8, and 9 years old. Overall, short- and long-term outcomes for HV and control mothers did not differ significantly. Demographic attributes, a general measure of overall maternal risk, and partner violence did not moderate program impact on psychosocial functioning outcomes. Maternal relationship security did moderate program impact. Mothers who scored high on relationship anxiety but not on relationship avoidance showed the greatest benefits, particularly at the long-term follow-up. Mothers scoring high for both relationship anxiety and avoidance experienced some adverse consequences of home visiting. Further research is needed to determine mediating pathways and to inform and test ways to improve the targeting of home visiting and the tailoring of home visit service models to extend positive home visiting impacts to targeted families not benefiting from current models.  相似文献   
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Background

Liver dysfunction in children dependent on parenteral nutrition (PN) is well established, and the extent of hyperbilirubinemia has been shown to correlate with morbidity and mortality. The aim of this study was to assess whether increasing provisions of enteral nutrition can improve PN-associated hyperbilirubinemia over time.

Methods

A retrospective review was conducted on infants in our institution's Short Bowel Syndrome Clinic from 1999 to 2004. Inclusion criteria included PN duration more than 1 month, serum direct bilirubin more than 3 mg/dL while on PN, and tolerance of full enteral nutrition with eventual discontinuation of PN. Paired t tests were used for statistical analyses.

Results

Twelve infants were identified with a PN duration of 5 ± 1 months. Five patients underwent liver biopsy while on PN, and histological evidence of cholestasis was found on all specimens. Peak total and direct bilirubin levels were 10.5 ± 1.9 and 7.0 ± 1.6 mg/dL, respectively, and occurred at time of PN discontinuation. Only 2 patients had improvement in serum bilirubin levels before initiation of full enteral nutrition. After initiation of full enteral nutrition and discontinuation of PN, all patients achieved permanent normalization of bilirubin levels by 4 months (P < .05) after a 1-month plateau phase. Alkaline phosphatase levels approached reference range within this time but were not significant.

Conclusion

These data demonstrate for the first time that although PN-dependent infants can achieve normalization of marked hyperbilirubinemia with enteral nutrition, the improvement in liver function usually begins only after full enteral nutrition is tolerated and PN is withdrawn. These findings support the aggressive weaning of PN to enteral nutrition in infants with short bowel syndrome.  相似文献   
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INTRODUCTION

Concern exists regarding potential damage to the rotator cuff from repeated corticosteroid injections into the subacromial space.

PATIENTS AND METHODS

In this retrospective, case-controlled study, 230 consecutive patients presenting to three orthopaedic units with subacromial impingement and investigated as an end-point with magnetic resonance imaging (MRI) of the shoulder were divided into groups having received less than three or three or more subacromial injections of corticosteroids.

RESULTS

With no significant difference in age and sex distribution, analysis by MRI showed no significant difference between the two groups in the incidence of rotator cuff tear (P < 1.0).

CONCLUSIONS

This suggests that corticosteroid use in patients with subacromial impingement should not be considered a causative factor in rotator cuff tears.  相似文献   
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