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81.
A recently described solid phase immunoenzyme procedure (ELISPOT) has been adapted for the detection of individual cells secreting fibronectin. Simple and sensitive, this technique should find useful application for studying fibronectin production at the cellular level.  相似文献   
82.
83.
Cytokeratin markers come of age.   总被引:2,自引:0,他引:2  
Stig Linder 《Tumour biology》2007,28(4):189-195
Cytokeratins have been extensively used as serum tumour markers for monitoring of disease progression in cancer patients. The source of cytokeratins in the circulation as well as the mechanisms of release from cells have long been unclear. Recent evidence suggests that cytokeratins present in the circulation of cancer patients are released from apoptotic or necrotic tumour cells. CK18 is cleaved by caspases during apoptosis and a monoclonal antibody (M30) specific to caspase-cleaved forms is available. The molecular form of CK18 released from cells (caspase-cleaved or not) can conveniently be determined by immunoassays (M30-Apoptosense and M65 ELISA assays; Peviva AB, Bromma, Sweden) to determine cell death mode--apoptosis or necrosis. Recent studies where these assays were used to evaluate the response to cytotoxic anticancer drugs using cancer patient serum have been encouraging. CK18 is attracting considerable interest as a response biomarker during clinical trials of anticancer drugs. Properties such as excellent antigen stability and the epithelial specificity of cytokeratins contribute to make this biomarker attractive.  相似文献   
84.
BACKGROUND: The aim of the present study was to evaluate a series of biomarkers with regard to long-term prognostic value in patients with T1 (< or =2 cm) node-negative breast cancer. METHOD: The prognostic value of Ki-67, p53, oestrogen receptor (ER) immunohistochemical labelling, flow-cytometric S phase fraction and ploidy was evaluated in 212 patients with pT1N0M0 breast cancer. The median follow-up time was 15.9 years (range 0.2-27.2 years). RESULTS: In an analysis of breast cancer-specific survival up to 5 years, high Ki-67 (> or =10%; p = 0.002), high p53 (> or =20%; p = 0.01), negative ER (<30%; p = 0.01) as well as aneuploidy of the tumour (p = 0.02) were significant prognostic factors. When the follow-up was extended to 10 years, only Ki-67 (p = 0.03) was significantly associated with outcome and beyond 15 years none of the studied markers provided significant prognostic information when analyzed separately. There was a weak but significant difference in long-term survival when patients with a combination of high Ki-67 (> or =10%), high SPF (>3%) and high p53 (> or =20%) were compared to patients with other combinations (p = 0.03). CONCLUSION: According to the results of our series, it seems that several prognostic markers which are associated with short-term survival (< or =5 years) in pT1N0M0 breast cancer may not be significant predictors of long-term (>15 years) breast cancer-specific survival.  相似文献   
85.

Background  

Obesity has primarily been addressed with interventions to promote weight loss and these have been largely unsuccessful. Primary prevention of obesity through support of weight maintenance may be a preferable strategy although to date this has not been the main focus of public health interventions. The aim of this study is to characterize who is not gaining weight during a 10 year period in Sweden.  相似文献   
86.
Patients with clinically node negative resectable breast cancer were randomized to either mastectomy only or radical mastectomy and radiotherapy, and followed for 15-20 years. During follow-up axillary metastases occurred with the same frequency after mastectomy as was initially observed in the group that underwent axillary dissection. There was no significant survival difference between the two groups. When adjusting the treatment effect for differences in age, tumour size, lymph node metastases, and histology, the outcome after radical mastectomy plus irradiation was significantly inferior. Comedo carcinoma proved also in this study to carry a poor prognosis.  相似文献   
87.
We studied histological samples and clinical data from 111 breast carcinoma patients originally treated in 1975-1977 who did not have distant metastases at the time of diagnosis. A multivariate survival analysis using the Cox model selected the studied variables in the following order according to their prognostic association (breast cancer deaths, or deaths from any cause): axillary lymph node status, tumor size, mitotic index, and DNA ploidy status. The association of the different variables to the prognosis in respect to breast cancer deaths was evaluated 1-10 years after treatment by stepwise logistic regression. Lymph node status, tumor size, mitotic index, and DNA ploidy all showed significant relation to the prognosis but this association varied considerably with time of observation.  相似文献   
88.
89.
OBJECTIVE: The iodine intake level is important for the occurrence of thyroid disorders in a population. We have previously found that iodine in drinking water is related to iodine excretion but whether iodine is present as iodide or bound in other molecules remains unknown. DESIGN: We measured iodine in drinking water from 22 locations in Denmark. Six locations were selected by iodine content for further tap water analysis (Skagen 140 micro g/l, Samsoe 56 micro g/l, Nykoebing S. 50 micro g/l, Nakskov 40 micro g/l, Ringsted 38 micro g/l, Copenhagen 19 micro g/l). METHODS: HPLC size exclusion before (Skagen) and after (all sites) freeze drying and measurement of absorbance (280 nm) and iodine in fractions, and fluorescence spectroscopy of bulk organic matter in Skagen drinking water. RESULTS: Iodine content was unaltered after 3 Years (P=0.2). All samples contained organic molecules with characteristics similar to humic substances. Most iodine eluted with humic substances (Skagen 99%, Ringsted 98%, Nykoebing S. 90%, Copenhagen 90%, Samsoe 75%, Nakskov 40%). Changing pH and ionic strength and preincubation with iodide indicated that iodine was bound in humic substances. Humic substances may affect thyroid function but differ with geology. Geological and geochemical data agree with tap water humic substances having been released from marine deposits. Iodine is abundant in the marine environment and marine deposits are particularly rich in iodine. Correlation analysis (r=0.85, P=0.03) conform to iodine in drinking water, suggesting marine humic substances at the source rock. CONCLUSION: Iodine in Danish drinking water varied considerably. In drinking water with a high iodine content, the iodine mainly eluted with humic substances derived from marine source rock. We hypothesize that iodine in drinking water in general suggests coexisting humic substances of marine origin.  相似文献   
90.
Screening for anti-cancer substances iscommonly conducted using viability assays.An inherent problem with this approach isthat all compounds that are toxic andgrowth inhibitory, irrespective ofmechanism of action, will score positive.It would be beneficial to be able to screenfor compounds that specifically induceapoptosis. We here describe an ELISA-assaybased on a monoclonal antibody (M30) whichrecognizes a neo-epitope on cytokeratin 18exposed after cleavage by caspases duringapoptosis. We show that this assay detectsapoptosis in epithelial cells and that thesensitivity is sufficient for screening inthe 96-well format. We used the M30-ELISAassay to screen 500 low molecular weightcompounds from a chemical library from theNational Cancer Institute and identified 16drugs with strong pro-apoptotic activity,suggesting that the assay is a useful toolfor discovery of pro-apoptotic drugs.  相似文献   
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