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排序方式: 共有7178条查询结果,搜索用时 15 毫秒
971.
Adank MA Brogi E Bogomolniy F Wadsworth EA Lafaro KJ Yee CJ Kirchhoff T Meijers-Heijboer EJ Kauff ND Boyd J Offit K 《Familial cancer》2006,5(4):337-342
Background A major limitation in counseling unaffected women from families with inherited breast and ovarian cancer is that a “true-negative” interpretation of wild type BRCA analysis of the proband cannot be inferred in the absence of demonstration of a BRCA mutation segregating in the kindred. Documentation of familial BRCA mutations from paraffin-derived DNA of deceased patients has been limited due to reports of technical complications leading to lack of reproducibility of BRCA testing of archival material.Methods DNA was extracted from formalin-fixed paraffin-embedded (FFPE) morphologically normal tissue of 161 blinded, coded samples from women previously genotyped for the three Ashkenazi Jewish BRCA founder mutations from lymphocyte-derived DNA.Multiplex PCR followed by denaturing polyacrylamide gel electrophoresis was performed for the three founder mutations to determine if analysis on FFPE tissue could produce results concordant with those of the lymphocyte-derived DNA.Results After disclosure of the sample codes, the results were compared with the original lymphocyte-derived DNA genotypes. Excluding one sample unevaluable due to PCR failure, there was 100% concordance of 160 genotypes (120 mutation samples) derived from DNA from archival FFPE tissue compared to peripheral lymphocytes.Conclusions The method described reliably detected BRCA founder mutations in archival DNA derived from FFPE tissue. These results suggests that this technique may be useful in clinical settings to inform wild type BRCA results of unaffected probands, leading to avoidance of unnecessary intensified surveillance or risk-reducing surgery. With further validation this approach can also be applied to other populations where founder mutations are observed.M. A. Adank and E. Brogi are contributed equally to this work. 相似文献
972.
Martha L Sylvia Efrat Shadmi Chun-Ju Hsiao Cynthia M Boyd Alyson B Schuster Chad Boult 《Disease management》2006,9(1):56-62
The objective of this study was to describe the clinical features of older persons identified as high risk by a predictive modeling algorithm and to determine their suitability for clinical interventions like case management or disease management. A cross-sectional survey was undertaken at a community-based general internal medicine practice with 826 older patients enrolled in a Medicare-like health plan for military retirees and their dependents. Administrative claims data provided information about all 826 enrollees' chronic conditions, their use of health services, and the cost of those services during the past year. A survey mailed to 150 identified high-risk enrollees provided information about sociodemographic characteristics, general health, bed disability days, restricted activity days, activities of daily living (ADL) limitations, and instrumental activities of daily living (IADL) limitations. Compared to the 676 low-risk enrollees, the 150 high-risk enrollees had higher prevalence of eight individual chronic conditions, higher total chronic conditions (2.93 vs. 1.48, p < 0.001), higher annual rates of hospital admission (1.1 vs. 0.1, p < 0.001), more annual hospital days (7.3 vs. 0.5, p < 0.001), and higher total health insurance expenditures ($22,815 vs. $3,726, p < 0.001). The high-risk respondents to the survey (response rate = 80.0%) had suboptimal health (42.8% "fair or poor"), impaired functional ability (36.3% with 1+ ADL limitations, 58.1% with 1+ IADL limitations), and frequent health-related disruptions in their activities during the previous six months (38.7% with 1+ bed disability day, 52.3% with 1+ restricted activity day). A claims-based predictive modeling algorithm identifies older persons whose health, functional ability, and use of health services suggest they are good candidates for clinical interventions such as case management and disease management. 相似文献
973.
974.
A new class of amphiphiles with a glycerate headgroup, recently shown to form reverse hexagonal phase in excess water, have been dispersed to form Hexosome dispersions comprising sub-200 nm particles retaining the internal nanostructure of the parent H(II) phase. The application of these novel materials to the development of a new injectable formulation of irinotecan was investigated. The formulation of irinotecan with a small percentage of oleic acid in oleyl glycerate permitted a clinically relevant dose of irinotecan to be dissolved in the glycerate surfactant and dispersed in aqueous medium to form an injectable particle-based dose form of irinotecan. Importantly, incorporation of irinotecan into Hexosomes at neutral pH did not result in conversion from the active lactone to the inactive carboxylate form on storage, and is hence a promising alternative to the current low pH formulation of irinotecan required to inhibit this conversion. Although release of irinotecan from the Hexosomes was shown to be virtually instantaneous from the Hexosomes on substantial dilution, the retention of the drug in lactone form at neutral pH demonstrates a potential application of these novel nanostructured particles in injectable drug delivery. 相似文献
975.
Kolbrich EA Barnes AJ Gorelick DA Boyd SJ Cone EJ Huestis MA 《Journal of analytical toxicology》2006,30(8):501-510
Cocaine is rapidly metabolized to major metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME), and minor metabolites, norcocaine, p-hydroxycocaine, m-hydroxycocaine, p-hydroxybenzoylecgonine (pOHBE), and m-hydroxybenzoylecgonine. This IRB-approved study examined cocaine and metabolite plasma concentrations in 18 healthy humans who provided written informed consent to receive low (75 mg/70 kg) and high (150 mg/70 kg) subcutaneous cocaine hydrochloride doses. Plasma specimens, collected prior to and up to 48 h after dosing, were analyzed by gas chromatography-mass spectrometry (2.5 ng/mL limits of quantification). Cocaine was detected within 5 min, with mean+/-SE peak concentrations of 300.4+/-24.6 ng/mL (low) and 639.1+/-56.8 ng/mL (high) 30-40 min after dosing. BE and EME generally were first detected in plasma 5-15 min post-dose; 2-4 h after dosing, BE and EME reached mean maximum concentrations of 321.3+/-18.4 (low) and 614.7+/-46.0 ng/mL (high) and 47.4+/-3.0 (low) and 124.4+/-18.2 ng/mL (high), respectively. Times of last detection were BE>EME>cocaine. Minor metabolites were detected much less frequently for up to 32 h, with peak concentrations相似文献
976.
977.
A note on the description of pain and its causes 总被引:1,自引:0,他引:1
The adjectives used by 72 psychiatric patients to describe pain were examined. Patients with physical lesions tended to have physical precipitants and physical relieving factors. Patients with psychologically based pain often recognized both physical and emotional preciptation. Most adjectives used were sensory rather than affective or evaluative. 相似文献
978.
979.
We have calculated that the high thiaminase activity in the rumen of CCN-affected animals could degrade all the thiamine usually ingested and synthesized.We have confirmed that thiaminase-producing B. thiaminolyticus and Cl. sporogenes can be isolated from heat-treated rumen contents of CCN-affected sheep and cattle. The thiaminase from cultures of these bacteria is more active with the co-substrates pyridine, 3-picoline and pyridoxine than with aniline, whereas with the thiaminase from rumen fluid and faecal extracts the converse is true. The thiaminase of faecal extracts can use certain pyrrole and imidazole derivatives as co-substrates whereas the bacterial thiaminases cannot. There are also marked differences in membrane filtration, gel filtration, electrophoretic mobility and pH dependence. We conclude that neither B. thiaminolyticus nor Cl. sporogenes is the real source of rumen thiaminase. 相似文献
980.