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21.
Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
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平贝碱乙的分离和鉴定   总被引:5,自引:0,他引:5  
本文报道了自东北平贝母(Fritillaria ussuriensis Maxim)中分得一种新的甾体生物碱,经光谱(IR,MS,1HNMR及13CNMR)解析和衍生物制备,推定其结构为5α,17β,22α-cevanine-3 β,6α,12α,14α,16β,20β-hexol,定名为平贝碱乙。  相似文献   
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Hepatic Resection for Colorectal Metastasis: Impact of Tumour Size   总被引:1,自引:0,他引:1  
Background Many colorectal liver metastasis patients are denied surgical resection on the basis of tumour size. The aim of this study was to explore the impact of metastasis size on modern liver resection.Methods Using a prospectively collected database, this was a retrospective analysis of 484 consecutive patients who underwent liver resection for colorectal liver metastases between 1993 and 2003. The cohort was divided into two groups: smaller metastases (<8 cm) and larger metastases (≥ 8 cm). Those with larger metastases were then further stratified into big metastases (8–12 cm) and giant metastases (>12 cm). Demographic, pathological, surgical technique and outcome data were compared between the groups.Results There were 88 (18%) patients with metastases measuring 8 cm or larger. There was an association between higher carcinoembryonic antigen (CEA) and cancer antigen (CA) 19-9 levels and larger metastases. The actuarial 5-year survival for patients with larger metastases was 38% compared with 42% for smaller metastases (not statistically significant). Patients with giant metastases had poorer overall and disease-free survival (both nonsignificant) compared with those with big metastases: 29% and 28% at 5 years, respectively.Conclusion Patients with colorectal liver metastasis greater than 8 cm and up to 12 cm in size should not be treated differently from those with smaller lesions.  相似文献   
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Computed tomographic detection of nonbeta pancreatic islet cell tumors   总被引:6,自引:0,他引:6  
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Objective

This article focuses on approaches within clinical practice that seek to actively involve patients with long‐term conditions (LTCs) and how professionals may understand and implement them. Personalized care planning is one such approach, but its current lack of conceptual clarity might have impeded its widespread implementation to date. A variety of overlapping concepts coexist in the literature, which have the potential to impair both clinical and research agendas. The aim of this article is therefore to explore the meaning of the concept of care planning in relation to other overlapping concepts and how this translates into clinical practice implementation.

Methods

Searches were conducted in the Cochrane database for systematic reviews, CINHAL and MEDLINE. A staged approach to conducting the concept mapping was undertaken, by (i) an examination of the literature on care planning in LTCs; (ii) identification of related terms; (iii) locating reviews of those terms. Retrieved articles were subjected to a content analysis, which formed the basis of our concept maps. (iv) We then appraised these against knowledge and experience of the implementation of care planning in clinical practice.

Results and Conclusions

Thirteen articles were retrieved, in which the core importance of patient‐centredness, shared decision making and self‐management was highlighted. Literature searches on these terms retrieved a further 24 articles. Our concept mapping exercise shows that whilst there are common themes across the concepts, the differences between them reflect the context and intended outcomes within clinical practice. We argue that this clarification exercise will allow for further development of both research and clinical implementation agendas.  相似文献   
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