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1.
Cell adhesion to the extracellular matrix appears to trigger a cascade of intracellular signalings. We have previously shown that treatment of ovarian cancer cells, NOM1, with fibronectin (FN) stimulated matrix metalloproteinase (MMP)-9 secretion and thereby activated the invasiveness of cells via the FAK/Ras signaling pathway. By use of chemical inhibitors, we investigated the downstream effectors critical for FN-dependent secretion of MMP-9. Treatment of cells with MEK1 inhibitors, U0126 and PD98059, dramatically suppressed the secretion of MMP-9 activated by FN. Similarly, PI-3 kinase inhibitors, Wortmannin and LY294002, strongly suppressed the FN-dependent secretion of MMP-9 together with the inhibition of Akt activation. In contrast, a specific PKC inhibitor (GF109203X) showed no inhibitory effect on the FN-dependent MMP-9 secretion. Moreover, we found that both the MEK1 inhibitor and the PI3-K inhibitor, but not the PKC inhibitor, strongly suppressed the invasiveness of NOM1 cells. Taken together, our results suggest that activation of dual signaling pathways, MEK1-MAPK and PI3K-Akt, is required for the FN-dependent activation of MMP-9 secretion. Our results suggest the importance of these signaling molecules as a chemotherapeutic target for cancer. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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CONTEXT: Endometrioid carcinoma is often preceded by characteristic histopathologic lesions known as endometrial hyperplasia. Estrogen appears to be involved in the development of endometrioid carcinoma. Other mechanisms of endometrial carcinogenesis include mutations in p53 and PTEN tumor suppressor genes and overexpression of cyclin D1. However, the pattern of cyclin D1 expression is not well defined in normal, hyperplastic, neoplastic, and metaplastic endometrium. DESIGN: Cyclin D1 immunohistochemical analysis was used to evaluate 108 fixed, paraffin-embedded endometrial biopsy specimens and uterine resections obtained from 108 patients. Specimens included proliferative and secretory endometria, simple and complex hyperplastic lesions, and endometrioid adenocarcinoma. Normal and metaplastic surface epithelia were also evaluated independently of glandular morphologic features. RESULTS: Cyclin D1 was significantly overexpressed in glands with complex hyperplasia and endometrioid adenocarcinoma compared with proliferative or secretory endometrium and simple hyperplasia. Significant overexpression was also noted in papillary, syncytial, and squamous metaplasias compared with normal surface epithelium or epithelium with tubal metaplasia. CONCLUSION: Overexpression of cyclin D1 increases from normal endometrium to hyperplasia and carcinoma, suggesting that it may play a role in endometrial carcinogenesis. Overexpression of cyclin D1 in endometrial glands was independent from overexpression of cyclin D1 in surface metaplastic epithelium.  相似文献   
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The 2001 Bethesda system (TBS 2001) eliminated the "satisfactory but limited by" category, benign cellular changes (BCC), and the designations "favor benign" (ASC-B) and "favor low grade" (ASC-L) for atypical squamous cells. We compared the unsatisfactory rate and atypical squamous cells:squamous intraepithelial lesions (ASC:SIL) ratio pre- and postimplementation of TBS 2001 to see if there was an increase in unsatisfactory specimens, ASC rate, and altered ASC:SIL ratio. Pap Tests (569,726) reviewed at the Cytopathology Laboratory of Women and Infants Hospital from 1998-2002 were included. TBS 1991 terminology was used through December 31, 2001. Conversion to TBS 2001 took place on January 1, 2002. The average ASC:SIL ratios pre- and postimplementation of TBS 2001 were 1.52:1 and 1.42:1, respectively. The rates of unsatisfactory specimens and ASC remained unchanged. Conversion to TBS 2001 did not adversely affect the ASC:SIL ratio or the detection rates of abnormalities of Pap tests.  相似文献   
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Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy for providing essential minimum health care to all has been actively pursued. An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on recent trends based upon relevant data and information. Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local, and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services to enhance the services of health facilities.  相似文献   
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Nanoscale CuO with diameters in the range of 7–8 nm has been synthesized via a two-step precipitation–calcination method using copper(ii) isonicotinate tetrahydrate as the precursor. The first step involves the room temperature stirring of an alkaline ethanolic solution of the precursor which gives a non-crystalline CuO species, while the second step involves the calcination of the product of the first step at 180 °C to form nanocrystalline CuO which has been characterized by PXRD, TEM, SEM, H2-TPR and Raman spectroscopy, etc. The CuO material has shown excellent catalytic activity in the oxidation of styrene using TBHP as the oxidizing agent leading to complete styrene conversion with more than 95% styrene oxide selectivity at the end of 6 h. The oxide catalyst can be reused for at least 6 successive runs without significant loss in activity.

Nanoscale CuO with diameters in the range of 7–8 nm has been synthesized via a two-step precipitation–calcination method using copper(ii) isonicotinate tetrahydrate as the precursor.  相似文献   
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