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961.
962.
H Irene Hall Lee S Caplan Steven S Coughlin Robert S Levine Kangmin Zhu 《Annals of epidemiology》2002,12(1):15-20
PURPOSE: In case-control studies, the issue of whether living or deceased controls should be used for deceased cases has been controversial. METHODS: Using data from a study of cancer among men that selected both live (n = 1910) and deceased controls (n = 596) for cases of liver cancer (109 deceased, 59 living), we examined the effects of using information from proxy respondents (cases and controls) and from live cases and controls on associations between liver cancer and known risk factors. Cases diagnosed between 1984 and 1988 were selected from eight population-based cancer registries. Live controls were recruited by random digit dialing, deceased controls from death certificate files. Controls were matched to cases on geographic area, year-of-birth, and race. RESULTS: Adjusted odds ratios (OR) calculated for deceased cases and controls, when compared to odds ratios for live cases and controls, were attenuated towards the null value for history of hepatitis (4.7 vs. 14.9), blood transfusions (1.1 vs. 7.8), and cirrhosis (9.3 vs. 51.1). When all cases and living controls were used, odds ratios did not differ substantially from those for living cases and controls except for cirrhosis (OR = 154.2). For smoking, the odds ratios were similar in all analyses. Adjustment for type of interview (self, proxy) did not eliminate differences between results for living and deceased subjects; significant interactions were found between type of interview and hepatitis, cirrhosis, and blood transfusions. CONCLUSIONS: Selection of live controls for deceased cases is recommended to decrease misclassification in measures of exposure. 相似文献
963.
964.
Waldenstrom Macroglobulinemia (WM) is a B-cell disorder characterized by the infiltration of the bone marrow (BM) with lymphoplasmacytic cells, as well as detection of an IgM monoclonal gammopathy in the serum. WM is an incurable disease, with an overall medial survival of only 5-6 years. First-line therapy of WM has been based on single-agent or combination therapy with alkylator agents (e.g. chlorambucil or cyclophasphamide), nucleoside analogues (cladribine or fludarabine), and the monoclonal antibody rituximab. Novel therapeutic agents that have demonstrated efficacy in WM include thalidomide, lenalidomide, bortezomib, everolimus, Atacicept, and perifosine. The range of the ORR to these agents is between 25-80%. Ongoing and planned future clinical trials include those using PKC inhibitors such as enzastaurin, new proteasome inhibitors such as carfilzomib, histone deacetylase inhibitors such as panobinostat, humanized CD20 antibodies such as Ofatumumab, and additional alkylating agents such as bendamustine. These agents, when compared to traditional chemotherapeutic agents, may lead in the future to higher responses, longer remissions and better quality of life for patients with WM. 相似文献
965.
966.
967.
Cathy S Lim Irene Ngu Ann P Collins Geoff M W McKellar 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2008,105(1):e28-e33
A 91-year-old man presented with an asymptomatic swelling in the roof of his mouth. Clinically the lesion was nontender and appeared cystic. A CT scan showed a soft tissue swelling of his palate with no bony involvement. An orthopantogram and blood tests were noncontributory. A fine-needle aspiration biopsy was suggestive of a minor salivary gland neoplasm. An excision biopsy showed papillary cystadenoma of the minor salivary gland, with numbers of psammoma bodies. A stepwise approach is demonstrated in the diagnosis of this rare minor salivary gland neoplasm. To the authors' best knowledge, this is the 12th case of this tumor seen in the palate. Furthermore, no previous case has included a fine-needle aspiration biopsy in the work-up, the cytological features of which will be described. 相似文献
968.
Massive bleeding is a major cause of intraoperative death or death in the immediate postoperative period as a result of surgery. The present article describes the basic principles for the control of surgical bleeding as well as temporary and definitive maneuvers. Temporary control of bleeding can often be achieved with simple maneuvers, which may not be definitive, in which case damage control or planned reoperation are required.The surgeon's aim should always be to control the bleeding. If simple maneuvers fail, more complex procedures are required. The present article also describes these maneuvers to control bleeding (Pringle's maneuver, total vascular exclusion, atrial caval shunt, Mattox's maneuver, Cattel Braasch maneuver, Kocher's maneuver and aortic control maneuvers). 相似文献
969.
Anastasia Khvorova Yong-Geun Kwak Michael Tamkun Irene Majerfeld Michael Yarus 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(19):10649-10654
The RNA world hypothesis presumes that RNA will be competent for varied essential cellular functions. One such indispensable cell function is regulation of membrane permeability. Though this was not a known RNA activity, selection-amplification yielded RNAs that bound phosphatidylcholine:cholesterol liposomes. At least eight distinct, approximately 95-mer sequences bind well to the outside of the lipid bilayer, though randomized sequences had no such activity. No distinct sequence motif for lipid binding was found. However, truncation of one such RNA shows that a smaller, 44-nucleotide irregular RNA hairpin is an active membrane binding domain. Bound RNA increases the permeability of liposomes to (22)Na(+). In addition, using voltage clamp technique, four individual RNAs increase the ion permeability of the plasma membrane of cultured human cells. The existence of multiple sequences that bind membranes and provoke permeability changes suggests that these may be elementary RNA functions that could be selected in vivo. 相似文献
970.
Irene Banti Susanna Nencetti Elisabetta Orlandini Annalina Lapucci Maria Cristina Breschi Stefano Fogli 《The Journal of pharmacy and pharmacology》2009,61(8):1057-1066
Objectives The aim of the study was to evaluate the antitumour effect in vitro of newly synthesized 7‐substituted 2,3‐dihydro‐1,8‐naphthyridines. Methods Characterization tools included cell viability assay, caspase 3/7 induction, DNA fragmentation, fibroblast growth factor type 1 receptor kinase inhibition, and in‐vitro antiangiogenic analysis. Key findings Treatment of MIA PaCa‐2 human pancreatic cancer cells with test compounds showed time‐ and concentration‐dependent cytotoxicity with IC50 values in the micromolar range. Compounds with an aminoalkyl or a diaminoalkyl side chain at the 7‐position exhibited remarkable cytotoxicity, whereas the presence of a methyl group or a cyclic amine in the same position led to a significant decrease in their biological activity. Cytotoxicity screening demonstrated that the most active was compound 11 (mean 50% inhibition of cell proliferation (IC50) 11 μM). This compound had an in‐vitro antitumour efficacy superior to 5‐fluorouracil (the lowest cell viability value after treatment (Emax) 0.2% and 19%, respectively) and proved to be less toxic than 5‐fluorouracil against non‐cancerous human oral epithelial cells. In addition, compound 11 induced apoptosis in MIA PaCa‐2 cells and it was able to promote antiangiogenic effects in vitro. Finally, its cytotoxicity was enhanced in pancreatic cancer cells stimulated with fibroblast growth factor, while no substantial effect was observed on human bronchial smooth muscle cells stimulated with the same growth factor. Conclusions These findings suggest that 1,8‐naphthyridine derivatives are a promising class of compounds in cancer research. In particular, the antitumour activity of compound 11 is worth further investigation. 相似文献