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11.
The incidence of uterine cervical cancer has increased slightly in Western countries, with an increase in relatively young women. Overexpression of matrix metalloproteinases (MMPs)-2 and -9 has turned out as a prognostic factor in many cancers. We compared the expression of the proteins MMP-2 and MMP-9 in cervical primary tumors with clinical outcome and risk factors of cervical cancer. One hundred sixty-one patients with cervical cancer treated in Ume? University Hospital or Sahlgrenska University Hospital, Sweden, between 1991 and 1995 were included in the study. Paraffin-embedded tissue samples obtained prior to treatment were examined immunohistochemically by specific antibodies for MMP-2 and MMP-9. Forty-two percent of the tumors were intensively positive for MMP-2 and 31% for MMP-9. Nineteen percent of the samples were intensively positive for both proteinases and 47% negative or weak for both. Overexpression of MMP-2 seemed to predict unfavorable survival under Kaplan-Meier analysis and in the multivariate analysis. Early sexual activity and low parity seemed to correlate to overexpression of MMP-2. MMP-9 was not associated with survival or sexual behavior. Intensive MMP-9 was noted in grade 1 tumors. We conclude that MMP-2 and MMP-9 have different roles in uterine cervical cancer. MMP-2 could be associated with aggressive behavior, but MMP-9 expression diminishes in high-grade tumors.  相似文献   
12.
In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain.  相似文献   
13.
BACKGROUND: 1Alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2) Vitamin D(3)] induces growth inhibition in squamous cell carcinoma (SCC) cell lines of the head and neck by arresting the cells in the G0/G1 phase of the cell cycle, probably due to an enhanced expression of p21, which could be demonstrated in other cell lines (JPPA, SCC9) before. In SCC25, a SCC cell line isolated from tongue, growth inhibition but no overexpression of p21 was detected. The retinoblastoma gene, as a direct target of G1 cyclin-CDK complexes, showed an obvious shift from the hyperphosphorylated to the hypophosphorylated form under 1,25(OH)(2)Vitamin D(3), which indicates that the growth inhibition takes place in the G0/G1 phase. To explore the possible pathway of growth inhibition in SCC25 we investigated other cell cycle inhibitors (p18, p19, p27). METHODS: Synchronized cells were treated with 1,25(OH)(2)Vitamin D(3) over 96 h. The cell cycle status and expression of cell cycle-regulating proteins was determined by fluorescence-activated cell sorting (FACS) and Western blotting. An overexpression of p18 in 1,25(OH)(2)Vitamin D(3) vs. ethanol-treated cells was determined until 30 h in SCC25. No influence was detectable on the expression of p27 and p19. CONCLUSION: One mechanism by which 1,25(OH)(2)Vitamin D(3) controls cell growth might be the upregulation of p21. As p21 was unsusceptible to 1,25(OH)(2)Vitamin D(3) in SCC25, other inhibiting proteins were necessary to be tested. The proven upregulation of p18 seems to be the responsible step for growth inhibition of 1,25(OH)(2)Vitamin D(3) in SCC25.  相似文献   
14.
本文提出了我国医疗器械产业中数字化技术发展中存在的主要问题,并分析了问题产生的原因。  相似文献   
15.
The decoction of Sclerocarya birroea Hochst. shows hypoglycaemic effects, an increase in plasma IRI in normal rats and an incremented oral-glucose tolerance. The decoction is also active against diet-induced hypercholesterolaemia.  相似文献   
16.
The region is characterized by diversity in cultural, political, economic and health conditions. Blindness in the region varies from 6.4% to 0.2% with cataract ranking highly as an underlying cause. There is a need to develop national policies to deliver affordable, technically suitable, and cost effective management plans to reduce cataract. Economic, demographic, health, and manpower statistics are essential information to be considered in formulating such policies.  相似文献   
17.
Summary Twenty-two patients with recurrent or metastatic squamous cell carcinoma of the head and neck were treated with piroxantrone 150 mg/m2 intravenously every 21 days. There were no objective responses. The 95% upper confidence bound for response is 15%. Primary toxicity was hematologic.  相似文献   
18.
Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores, bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix.  相似文献   
19.
74例小儿慢性头痛经辨证治疗,显效80.95%,好转16.67%,无效2.38%。痰浊头痛二陈汤或半夏白术天麻汤加减;肾虚头痛,杞菊地黄汤加减;淤血头痛,补阳还五汤;气血虚头痛八珍汤加减。指出了小儿内伤头痛的病因病机,并指出脑电图,脑阻抗血流图、CT、甲皱微循环可做为此病的诊断及疗效指标。  相似文献   
20.
This report describes a model for identifying sets of teaching abilities considered to be effective for medical school teaching staff, based on roles teachers assume and functions they are expected to perform as instructors. The specification of these teaching abilities was the first step in the development of a comprehensive course on Medical Instruction at the Basic Institute of Medical and Agricultural Biology of the State University of Sao Paulo, Botucatu, Brazil, where the senior author is employed. The work was based on the assumption that medical school teachers are expected to assume a variety of teaching roles and that identification and specification of the abilities that define their roles can result in more effective and efficient teaching.  相似文献   
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