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排序方式: 共有212条查询结果,搜索用时 31 毫秒
11.
Phytotoxic properties of cnicin,a sesquiterpene lactone fromcentaurea maculosa (spotted knapweed) 总被引:4,自引:0,他引:4
Water and solvent extracts from the aerial tissues ofCentaurea maculosa, spotted knapweed, inhibited the root growth of lettuce. Column chromatography and lettuce bioassay of a chloroform extract led to the isolation of cnicin, a sesquiterpene lactone. Pure cnicin was bioassayed at 0, 1, 2, 4, 6, 8, and 10 mg/5 ml water with lettuce, created wheatgrass, bluebunch wheatgrass, rough fescue, western larch, lodgepole pine, and spotted knapweed. Germination was inhibited at one or more concentrations for all species except lodgepole pine and spotted knapweed. Growth, particularly of the roots, was retarded between 1 and 4 mg of cnicin. Lettuce, bluebunch wheatgrass, and spotted knapweed were inhibited significantly at all concentrations tested. 相似文献
12.
RD Rosenberg WC Hunt MR Williamson FD Gilliland PW Wiest CA Kelsey CR Key MN Linver 《Canadian Metallurgical Quarterly》1998,209(2):511-518
PURPOSE: To examine how common patient factors affect screening mammographic sensitivity and cancer stage at diagnosis. MATERIALS AND METHODS: The authors used a population-based database of 183,134 screening mammograms and a statewide tumor registry to identify 807 breast cancers detected at screening mammography. RESULTS: Sensitivity varied significantly with ethnicity, use of estrogen replacement therapy, mammographic breast density, and age. Sensitivity was 54% (13 of 24) in women younger than 40 years, 77% (121 of 157) in women aged 40-49 years, 78% (224 of 286) in women aged 50-64 years, and 81% (277 of 340) in women older than 64 years. Sensitivity was 68% (162 of 237) for dense breasts and 85% (302 of 356) for nondense breasts and 74% (180 of 244) in estrogen replacement therapy users and 81% (417 of 513) in nonusers. Sensitivity was most markedly reduced with the combination of dense breasts and estrogen replacement therapy use; there was little difference when only one factor was present. Median cancer size and the percentage of early cancers showed little change with any factors. CONCLUSION: Age is a minor determinant of mammographic sensitivity in women aged 40 years or older. Sensitivity is substantially decreased with the combination of higher breast density and estrogen replacement therapy use. There was not a notable shift in cancer outcomes in the groups with lower mammographic sensitivity. These data do not support different screening recommendations in women aged 40-49 years or in estrogen replacement therapy users. 相似文献
13.
Kelsey Charles A. Hixon Thomas J. Minifie Fred D. 《IEEE transactions on bio-medical engineering》1969,(2):143-147
A technique employing diagnostic ultrasound to evaluate lateral pharyngeal wall motion during connected discourse is described. The validity and reliability of the procedure are discussed. Typical displacement patterns are shown for normal speakers and applications to cleft palate and laryngectomized speakers discussed. 相似文献
14.
Synthetic and Biological Studies of Sesquiterpene Polygodial: Activity of 9‐Epipolygodial against Drug‐Resistant Cancer Cells 下载免费PDF全文
Dr. Ramesh Dasari Annelise De Carvalho Derek C. Medellin Kelsey N. Middleton Dr. Frédéric Hague Marie N. M. Volmar Prof. Liliya V. Frolova Dr. Mateus F. Rossato Jorge J. De La Chapa Nicholas F. Dybdal‐Hargreaves Akshita Pillai Prof. Véronique Mathieu Prof. Snezna Rogelj Prof. Cara B. Gonzales Prof. João B. Calixto Prof. Antonio Evidente Dr. Mathieu Gautier Dr. Gnanasekar Munirathinam Prof. Rainer Glass Prof. Patricia Burth Dr. Stephen C. Pelly Prof. Willem A. L. van Otterlo Prof. Robert Kiss Prof. Alexander Kornienko 《ChemMedChem》2015,10(12):2014-2026
Polygodial, a terpenoid dialdehyde isolated from Polygonum hydropiper L., is a known agonist of the transient receptor potential vanilloid 1 (TRPV1). In this investigation a series of polygodial analogues were prepared and investigated for TRPV1‐agonist and anticancer activities. These experiments led to the identification of 9‐epipolygodial, which has antiproliferative potency significantly exceeding that of polygodial. 9‐Epipolygodial was found to maintain potency against apoptosis‐resistant cancer cells as well as those displaying the multidrug‐resistant (MDR) phenotype. In addition, the chemical feasibility for the previously proposed mechanism of action of polygodial, involving the formation of a Paal–Knorr pyrrole with a lysine residue on the target protein, was demonstrated by the synthesis of a stable polygodial pyrrole derivative. These studies reveal rich chemical and biological properties associated with polygodial and its direct derivatives. These compounds should inspire further work in this area aimed at the development of new pharmacological agents, or the exploration of novel mechanisms of covalent modification of biological molecules with natural products. 相似文献
15.
Lee Connie M. S. Fong Kenneth N. K. Mok Maggie M. Y. Lam M. K. Kung Y. Chan Paven P. W. Ma Maggie K. M. Lui S. L. Kwan Lorraine P. Y. Chu W. L. Hui P. C. Yau Christina S. F. Kwan Ivan W. L. Chan Kelsey Y. M. Chan T. M. 《Virtual Reality》2023,27(3):1571-1583
Virtual Reality - Cognitive impairment is not uncommon in patients with end-stage renal disease and can make it more difficult for these patients to carry out peritoneal dialysis (PD) on their own.... 相似文献
16.
KM Koslowski PR Shaver JT Casey T Wilson G Yamanaka AK Sheaffer DJ Tenney NE Pederson 《Canadian Metallurgical Quarterly》1999,73(2):1704-1707
Herpes simplex virus (HSV) DNA is cleaved from concatemers and packaged into capsids in infected cell nuclei. This process requires seven viral proteins, including UL15 and UL28. UL15 expressed alone displays a nuclear localization, while UL28 remains cytoplasmic. Coexpression with UL15 enables UL28 to enter nuclei, suggesting an interaction between the two proteins. Additionally, UL28 copurified with UL15 from HSV-infected cells after ion-exchange and DNA affinity chromatography, and the complex sedimented as a 1:1 heterodimer upon sucrose gradient centrifugation. These findings are evidence of a physical interaction of UL15 and UL28 and a functional role for UL15 in directing UL28 to the nucleus. 相似文献
17.
Richard J Bloomer Kelsey H Fisher-Wellman Kelley G Hammond Brian K Schilling Adrianna A Weber Bradford J Cole 《Journal of the International Society of Sports Nutrition》2009,6(1):4-2
Correction to Richard J Bloomer, Kelsey H Fisher-Wellman, Kelley G Hammond, Brian K Schilling, Adrianna A Weber and Bradford
J Cole: Dietary supplement increases plasma norepinephrine, lipolysis, and metabolic rate in resistance trained men. Journal of the International Society of Sports Nutrition 2009, 6: 4 相似文献
18.
SY James MA Williams SM Kelsey AC Newland KW Colston 《Canadian Metallurgical Quarterly》1997,54(5):625-634
The capabilities of 1alpha, 25-dihydroxyvitamin D3 (1,25(OH)2D3), and two novel vitamin D analogues, EB1089 and KH1060, to induce the differentiation of two established leukaemia cell lines, U937 and HL-60, were assessed alone or in combination with the retinoid compounds, 9-cis retinoic acid (9-cis RA) and all-trans retinoic acid (ATRA). The vitamin D derivatives acted to increase the differentiation of U937 and HL-60 cell cultures in a dose-dependent manner, as determined by nitroblue tetrazolium (NBT) reduction, with EB1089 and KH1060 being more effective than the native hormone. As an additional index of leukaemic cell differentiation, induction of expression of the phenotypic cell surface antigen, CD14, and the beta2-integrins, CD11b and CD18 by the vitamin D and retinoid compounds were monitored using fluorescence activated cell sorting (FACS) analyses. Following 96-hr treatment of U937 and HL-60 cells with 5 x 10(-10) M of the vitamin D derivatives, a striking increase in CD14 antigen expression was apparent, indicating the promotion by these compounds of a monocyte/macrophage lineage of cells. CD11b and CD18 antigen expression were also raised above control levels. In contrast, both retinoid compounds used at the higher concentration of 1 x 10(-8) M were not effective inducers of CD14 antigen expression. However, CD11b and CD18 were both readily increased in U937 and HL-60 cell cultures. Treatment of U937 cell cultures with the vitamin D compounds and the retinoids resulted in cooperative effects on induction of differentiation, with correlation by both NBT reduction and FACS analyses of CD14 antigen expression. The presence of 9-cis RA or ATRA appeared to contribute to the further increase of CD14 in these cells. HL-60 cell cotreatment with these compounds also displayed enhanced cooperative effects in phagocytic function by NBT reduction. However, analysis of CD14 revealed a dramatic diminution in HL-60 cells treated with the combinations of the vitamin D derivatives and the retinoids. Assessment of HL-60 cell morphology treated with these combinations demonstrated the presence of a mixed population of monocytes and granulocytes. CD11b and CD18 antigen expression was also enhanced in both cell lines with cotreatment. The ability of EB1089 and KH1060 to induce leukaemic cell differentiation may provide an additional option for therapeutic use alone or together with other differentiation agents such as 9-cis RA or ATRA. 相似文献
19.
Fehr KR Fehr KD Protudjer JL 《Revue canadienne de la pratique et de la recherche en diététique》2011,72(4):197-200
Folic acid reduces the risk of neural tube defects. As approximately 50% of pregnancies are unintended, women of reproductive age should be aware of the importance of folic acid. We reviewed the existing literature on these women's knowledge of folic acid and neural tube defects. Databases searched were PubMed, CINAHL, and Health Reference Center Academic. We used terms such as "folic acid knowledge" and "folic acid awareness" to search articles published from 1998 to 2010. Awareness of the benefits of folic acid before conception and during pregnancy was low, although knowledge levels were associated with education and household income. Women who were already knowledgeable about folic acid cited health care professionals, magazines and newspapers, and radio and television as common sources of information. Effective knowledge translation is needed to ensure that women are informed about the benefits of folic acid during the reproductive years. This knowledge will allow them to make informed decisions about folic acid consumption. Health care professionals play an influential role in promoting folic acid knowledge among women of childbearing age. Lower levels of knowledge among women with lower levels of education and/or household income must be addressed. 相似文献
20.
A case of acute myeloid leukaemia presenting as pyrexia of unknown origin and weight loss with pancytopenia is described. Initial investigations revealed trilineage myelodysplasia which evolved into acute myeloid leukaemia within 2 weeks of presentation. He was commenced on a standard induction regimen consisting of idarubicin, Ara-C and thioguanine. Throughout his hospital stay he remained febrile. In spite of exhaustive investigations no cause for the pyrexia was found nor did he respond to any form of treatment. He died after 9 weeks in hospital. His post-mortem examination revealed widespread disseminated tuberculosis without any reactive inflammatory tissue response or granuloma formation. 相似文献