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381.
鲨鱼软骨粉对小鼠移植性肿瘤的抑制作用与微血管的关系   总被引:2,自引:2,他引:2  
观察鲨鱼软骨粉对小鼠移植性SRS生长的影响与微血管密度的关系,方法肿瘤称重,切片用vWF疫组化染色及微血管计算机扫描方法半定量。结果在已建立的小鼠SRS实体瘤模型上应用口服鲨鱼软骨粉治疗,发现54毫克/d治疗15d后肿瘤重量及微血管密度较对照组明显减少。  相似文献   
382.
The prevalence of both obesity and disability is increasing globally and there is now growing evidence to suggest that these two health priorities may be linked. This paper explores the evidence linking obesity to muscular-skeletal conditions, mental health disorders and learning disabilities in both adult and child populations. The impact of obesity on the four most prevalent disabling conditions in the UK (arthritis, mental health disorders, learning disabilities and back ailments) has been examined through novel data analysis of the 2001 Health Survey for England and UK Back Exercise And Manipulation trial data. Together these analyses strongly suggest that whether the cause or result of disability, obesity is undeniably implicated, thus presenting a serious public health priority. Future research efforts are required to strengthen the evidence base examining obesity in back disorders, mental health and learning disabilities, in order to improve current clinical management.  相似文献   
383.
BACKGROUND: The relation between remodeling and left ventricular (LV) diastolic function has not yet been fully investigated. The aim of this study was to determine whether early assessment of Doppler-derived mitral deceleration time (DT), a measure of LV compliance and filling, may predict progressive LV dilation after acute myocardial infarction (AMI). METHODS AND RESULTS: Fifty-one patients (aged 61+/-11 years; 6 women) with anterior AMI successfully treated with direct coronary angioplasty underwent 2-dimensional and Doppler echocardiographic examinations within 24 hours of admission, at days 3, 7, and 30 and 6 months after the index infarction. Mitral flow velocities were obtained from the apical 4-chamber view with pulsed Doppler. End-diastolic volume index (EDVI) and end-systolic volume index (ESVI) were calculated with the Simpson's rule algorithm. Patients were divided according to the DT duration assessed at day 3 in 2 groups: group 1 (n=33) with DT >130 ms and group 2 (n=18) with DT 相似文献   
384.
Wilhide  CC; Van Dang  C; Dipersio  J; Kenedy  AA; Bray  PF 《Blood》1995,86(1):294-304
The maturation of megakaryocytes in vivo requires polyploidization or repeated duplication of DNA without cytokinesis. As DNA replication and cytokinesis are tightly regulated in somatic cells by cyclins and cyclin-dependent kinases, we sought to determine the pattern of cyclin gene expression in cells that undergo megakaryocytic differentiation and polyploidization. The Dami megakaryocytic cell line differentiates and increases ploidy in response to phorbol 12-myristate 13-acetate (PMA) stimulation in vitro. We used Northern blotting to analyze mRNA levels of cyclins A, B, C, D1, and E in PMA-induced Dami cells and found that cyclin D1 mRNA levels increased dramatically (18-fold). Similar increases in cyclin D1 mRNA were obtained for other cell lines (HEL and K562) with megakaryocytic properties, but not in HeLa cells. The increase in cyclin D1 was confirmed by Western immunoblotting of PMA-treated Dami cells. This finding suggested that cyclin D1 might participate in megakaryocyte differentiation by promoting endomitosis and/or inhibiting cell division. To address these possibilities, we constructed two stable Zn+2-inducible, cyclin D1-overexpressing Dami cell lines. Cyclin D1 expression alone was not sufficient to induce polyploidy, but in conjunction with PMA-induced differentiation, polyploidization was slightly enhanced. However, unlike other cell systems, cyclin D1 overexpression caused cessation of cell growth. Although the mechanism by which cyclin D1 may affect megakaryocyte differentiation is not clear, these data demonstrate that cyclin D1 is upregulated in differentiating megakaryocytic cells and may contribute to differentiation by arresting cell proliferation.  相似文献   
385.
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