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991.
992.
CS Skinner RK Sykes BS Monsees DA Andriole CL Arfken EB Fisher 《Canadian Metallurgical Quarterly》1998,25(1):60-78
Among older urban minority women, for whom breast cancer risk is high and the propensity to be screened is low, both social support and breast cancer knowledge have been linked to mammography use. The authors describe a theory-based breast cancer education program implemented via an existing informal network for low-income urban elderly coordinated by a social service agency. The program is both structured and flexible. Core education sessions include delineated content and methods and are led by health professionals. Participants choose from a variety of follow-up activities to promote screening within their community. Pre- and posttests administered among 80 program attendees in two sites indicate significant improvement in knowledge (p < .001). Program attendees in each site also planned and participated in follow-up activities to promote screening among their peers. Learn, Share, and Live seems to be an effective program for promoting breast cancer screening among older, urban, primarily minority women. 相似文献
993.
Thoracoscopy can be done safely and effectively through working ports placed in the axilla in patients whose pathology is in the upper half of the thorax. We have used this technique successfully in 37 patients with no complications. Advantages include superior cosmesis, optimal access to the apex of the chest, and, if necessary, easy conversion to axillary thoracotomy. 相似文献
994.
995.
X Wu K Senechal MS Neshat YE Whang CL Sawyers 《Canadian Metallurgical Quarterly》1998,95(26):15587-15591
The PTEN/MMAC1 phosphatase is a tumor suppressor gene implicated in a wide range of human cancers. Here we provide biochemical and functional evidence that PTEN/MMAC1 acts a negative regulator of the phosphoinositide 3-kinase (PI3-kinase)/Akt pathway. PTEN/MMAC1 impairs activation of endogenous Akt in cells and inhibits phosphorylation of 4E-BP1, a downstream target of the PI3-kinase/Akt pathway involved in protein translation, whereas a catalytically inactive, dominant negative PTEN/MMAC1 mutant enhances 4E-BP1 phosphorylation. In addition, PTEN/MMAC1 represses gene expression in a manner that is rescued by Akt but not PI3-kinase. Finally, higher levels of Akt activation are observed in human prostate cancer cell lines and xenografts lacking PTEN/MMAC1 expression when compared with PTEN/MMAC1-positive prostate tumors or normal prostate tissue. Because constitutive activation of either PI3-kinase or Akt is known to induce cellular transformation, an increase in the activation of this pathway caused by mutations in PTEN/MMAC1 provides a potential mechanism for its tumor suppressor function. 相似文献
996.
Julius Frerkes Hans Adolf Friedrichs Heinrich-Wilhelm Gudenau Werner Wenzel 《国际钢铁研究》1981,52(10):385-389
Kontinuierliche gravimetrische Messung der Sauerstoffaufnahme zylindrischer Eisenschwammpreßlinge bei 700 bis 1300°C in einem Gasstrom mit bis zu 40 % CO2, CO, H2O, H2 in unterschiedlichem Verhältnis. Ermittlung des Porendiffusionskoeffizienten und der Geschwindigkeitskonstante der Phasengrenzreaktion aus dem Vergleich von Rechnung und Messung. 相似文献
997.
In Experiment 1, rats were given a 1% lead acetate diet from Day 100 of life to the termination of the experiment. After 82 days of lead feeding behavioral tests were started. Lead exposure increased wheel-turning hyperactivity produced by food deprivation and phenylethylamine injection. Lead produced no activity change in the unchallenged condition. In the open field, lead-exposure rats were less responsive to the stimulating action of PEA and amphetamine and to the sedating action of pentobarbital. In Experiment 2, the interaction of lead with food deprivation of PEA on wheel-turning was replicated in naive animals given only a 32-day exposure. Chemical analysis was made of tissues. Ingested lead entered the brain. Regional steady-state levels of brain norepinephrine, dopamine and serotonin were not altered by lead treatment when measured following four days of starvation at a time when lead-induced behavioral change was distinct. It was concluded that pharmacological challenges on activity may be sensitive indicators of lead exposure, but the type of activity measure is critical. 相似文献
998.
999.
Production of pharmaceutical grade plasmid DNA is an important issue in gene therapy. We developed a method for affinity purification of plasmids by triple helix interaction. This method is based on sequence-specific binding of an oligonucleotide immobilized on a large pore chromatography support to a target sequence on the plasmid. Using design criteria derived from thermodynamic data, we produced a 15mer target sequence which binds strongly to the affinity support under mildly acidic conditions. Plasmid DNA was purified from clarified Escherichia coli lysate by incubation with the affinity beads at pH 5.0 and high NaCl concentration. After extensive washing of the beads, purified plasmid DNA was eluted with alkaline buffer. The purified plasmid showed no RNA or cell DNA contamination in HPLC analysis and total protein concentration was reduced considerably. Due to its mechanical stability and porosity this support can be used in a continuous affinity purification process, which has a high potential for scale up. 相似文献
1000.
Cardiac effects of adjuvant doxorubicin and radiation therapy in breast cancer patients 总被引:1,自引:0,他引:1
CL Shapiro PH Hardenbergh R Gelman D Blanks P Hauptman A Recht DF Hayes J Harris IC Henderson 《Canadian Metallurgical Quarterly》1998,16(11):3493-3501
PURPOSE: To assess the cardiac effects of two different cumulative doses of adjuvant doxorubicin and radiation therapy (RT) in breast cancer patients. PATIENTS AND METHODS: Two hundred ninety-nine breast cancer patients were prospectively randomized to receive either five cycles (CA5) or 10 cycles (CA10) of adjuvant treatment with cyclophosphamide (500 mg/ m2) and doxorubicin (45 mg/m2) administered by intravenous bolus every 21 days. One hundred twenty-two of these patients also received RT. Estimates of the cardiac RT dose-volume were retrospectively categorized as low, moderate, or high. The risk of major cardiac events (congestive heart failure, acute myocardial infarction) was assessable in 276 patients (92%), with a median follow-up time of 6.0 years (range, 0.5 to 19.4). RESULTS: The estimated risk (95% confidence interval) of cardiac events per 100 patient-years was significantly higher for CA10 than for CA5 [1.7 (1.0 to 2.8) v 0.5 (0.1 to 1.2); P=.02]. The risk of cardiac events in CA5 patients, irrespective of the cardiac RT dose-volume, did not differ significantly from rates of cardiac events predicted for the general female population by the Framingham Heart Study. In CA10 patients, the incidence of cardiac events was significantly increased (relative risk ratio, 3.6; P < .00003) compared with the Framingham population, particularly in groups that also received moderate and high dose-volume cardiac RT. CONCLUSION: Conventional-dose adjuvant doxorubicin as delivered in the CA5 regimen by itself, or in combination with locoregional RT, was not associated with a significant increase in the risk of cardiac events. Higher doses of adjuvant doxorubicin (CA10) were associated with a threefold to fourfold increased risk of cardiac events. This appears to be especially true in patients treated with higher dose-volumes of cardiac RT. Larger studies with longer follow-up periods are needed to confirm these results. 相似文献