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排序方式: 共有6119条查询结果,搜索用时 15 毫秒
51.
Edward Chow Lori Holden Joel Rubenstein Monique Christakis Katharina Sixel Marjan Vidmar Joel Finkelstein Charles Hayter Andrew Loblaw Rebecca Wong Ewa Szumacher Cyril Danjoux 《Radiotherapy and oncology》2004,70(3):291-294
Twenty-five patients with osteolytic metastases had computed tomography (CT) scans before and 3 months after palliative radiotherapy. The median % density change following single 8 Gy, 20 Gy/5#, 30 Gy/10# were: 128 (range 98–255), 141 (79–342), and 145 (65–235), respectively. It is feasible to evaluate remineralization of osteolytic lesions with palliative radiotherapy. 相似文献
52.
Ewa Surmacz Marina A. Guvakova Mary K. Nolan Roberto F. Nicosia Laura Sciacca 《Breast cancer research and treatment》1998,47(3):255-267
Experimental evidence suggests an important role of the type I IGF receptor (IGF-IR) in breast cancer development. Breast tumors and breast cancer cell lines express the IGF-IR. IGF-IR levels are higher in cancer cells than in normal breast tissue or in benign mammary tumors. The ligands of the IGF-IR are potent mitogens promoting monolayer and anchorage-independent growth of breast cancer cells. Interference with IGF-IR activation, expression, or signaling inhibits growth and induces apoptosis in breast cancer cells. In addition, recent studies established the involvement of the IGF-IR in the regulation of breast cancer cell motility and adhesion. We have demonstrated that in MCF-7 cells, overexpression of the IGF-IR promotes E-cadherin-dependent cell aggregation, which is associated with enhanced cell proliferation and prolonged survival in three-dimensional culture.The expression or function of the IGF-IR in breast cancer cells is modulated by different humoral factors, such as estrogen, progesterone, IGF-II, and interleukin-1. The IGF-IR and the estrogen receptor (ER) are usually co-expressed and the two signaling systems are engaged in a complex functional cross-talk controlling cell proliferation.Despite the convincing experimental evidence, the role of the IGF-IR in breast cancer etiology, especially in metastatic progression, is still not clear. The view emerging from cellular and animal studies is that abnormally high levels of IGF-IRs may contribute to the increase of tumor mass and/or aid tumor recurrence, by promoting proliferation, cell survival, and cell-cell interactions. However, in breast cancer, except for the well established correlation with ER status, the associations of the IGF-IR with other prognostic parameters are still insufficiently documented. 相似文献
53.
54.
Försti A Jin Q Altieri A Johansson R Wagner K Enquist K Grzybowska E Pamula J Pekala W Hallmans G Lenner P Hemminki K 《Breast cancer research and treatment》2007,101(1):83-93
Angiogenesis is an important step in the development of cancer. Vascular endothelial growth factor is a major regulator of
breast cancer angiogenesis, the effects of which are transmitted through the kinase domain receptor (KDR). Up-regulation of
KDR by periostin (POSTN) induces angiogenesis. We screened the KDR and the POSTN genes for published single nucleotide polymorphisms
(SNPs) and chose two SNPs in each gene for further analyses. We carried out a case–control study consisting of 412 familial
and 912 unselected breast cancer cases together with ethnically and geographically selected controls. Genotype, haplotype
and genotype combination analyses were carried out to evaluate their effect on susceptibility to and prognosis of breast cancer.
A haplotype in the POSTN gene was associated with an increased risk even after correction for multiple comparisons. Nominal
associations between the SNPs and prognostic indicators were also observed. Tumors of the KDR 472His allele carriers were
less often progesterone receptor negative according to both genotype and haplotype analyses (OR 0.61, 95%CI 0.40–0.92 and
OR 0.60, 95%CI 0.40–0.91, respectively). The POSTN -33G allele carriers had more often high grade and estrogen receptor negative
tumors (OR 1.75, 95%CI 1.02–3.01 and OR 1.70, 95%CI 1.04–2.78, respectively). The overall and cancer specific survival after
15 years of follow-up was more than 75%, and it did not depend on the genotype. Although a major effect of the SNPs in the
KDR and the POSTN genes on breast cancer susceptibility and prognosis was excluded, the effect of the POSTN C-33G SNP on prognosis
needs further characterization. 相似文献
55.
Grzegorz Borkowski Agnieszka Martya Marta Dobrosielska Piotr Marciniak Ewa Gabriel Julia Gowacka Marek Jabrzykowski Daria Pakua Robert E. Przekop 《Materials》2022,15(17)
In this study, the influence of carbonate lake sediments (Polylactide/Carbonate Lake Sediments–PLA/CLS) on the mechanical and structural properties of polylactide matrix composites was investigated. Two fractions of sediments originating from 3–8 and 8–12 m were analysed for differences in particle size by distribution (Dynamic Light Scattering–DLS), phase composition (X-ray Diffraction–XRD), the presence of surface functional groups (Fourier Transform-Infrared–FT-IR), and thermal stability (Thermogravimetric Analysis–TGA). Microscopic observations of the composite fractures were also performed. The effect of the precipitate fraction on the mechanical properties of the composites before and after conditioning in the weathering chamber was verified through peel strength, flexural strength, and impact strength tests. A melt flow rate study was performed to evaluate the effect of sediment on the processing properties of the PLA/CLS composite. Hydrophobic-hydrophilic properties were also investigated, and fracture analysis was performed by optical and electron microscopy. The addition of carbon lake sediments to PLA allows for the obtention of composites resistant to environmental factors such as elevated temperature or humidity. Moreover, PLA/CLS composites show a higher flow rate and higher surface hydrophobicity in comparison with unmodified PLA. 相似文献
56.
Bogdan Bujnicki Przemyslaw Sowinski Tomasz Makowski Dorota Krasowska Patrycja Pokora-Sobczak Inna Shkyliuk Jzef Drabowicz Ewa Piorkowska 《Materials》2022,15(21)
The microbiological purity of textiles plays a pivotal role in the use of textiles, especially in hospitals and other medical facilities. Microbiological purity of cotton fabric was achieved by a new disinfection method using tetrabutyloammonium OXONE (TBA-OXONE) before washing. As a result of the disinfection, the cotton fabric became microbiologically pure, despite the markedly decreased washing time with respect to the widely used standard procedure. Shortening of the washing time allowed for significant energy savings. In addition, the effect of the number of disinfection and washing cycles on the tensile properties and tearing force of the fabric was examined. After 120 disinfection and washing cycles the mechanical properties of cotton fabric were only slightly worsened. 相似文献
57.
Dominika Maciejewska-Markiewicz Arleta Drozd Joanna Palma Karina Ryterska Viktoria Hawrykowicz Patrycja Zaska Ewa Wunsh Katarzyna Kozowska-Petriczko Ewa Stachowska 《Nutrients》2022,14(20)
Background: Non-alcoholic fatty liver disease (NAFLD) is a wide spectrum condition characterized by excessive liver fat accumulation in people who do not abuse alcohol. There is no effective medical treatment for NAFLD; therefore, most important recommendations to reduce liver steatosis are diet and lifestyle, including proper physical activity. The aim of our study was to analyze the fatty acids and eicosanoids changes in the serum of patients who consumed high-fiber rolls for 8 weeks. Materials and Methods: The group of 28 Caucasian participants was randomly divided into two groups, those who received 24 g of fiber/day—from 2 buns of 12 g each (n = 14), and those who received 12 g of fiber/day—from 2 buns of 6 g (n = 14). At the beginning and on the last visit of the 8-week intervention, all patients underwent NAFLD evaluation, biochemical parameter measurements, and fatty acids and eicosanoids evaluation. Results: Patients who received 12 g of fiber had significantly reduced liver steatosis and body mass index. In the group who received 24 g of fiber/day, we observed a trend to liver steatosis reduction (p = 0.07) and significant decrease in aspartate aminotransferase (p = 0.03) and total cholesterol (p = 0.03). All changes in fatty acid and eicosanoids profile were similar. Fatty acids analysis revealed that extra fiber intake was associated with a significant increase in monounsaturated fatty acids and decrease in saturated fatty acids. Moreover, both groups showed increased concentration of gamma linoleic acid and docosahexaenoic acid. We also observed reduction in prostaglandin E2. Conclusions: Our study revealed that a high amount of fiber in the diet is associated with a reduction in fatty liver, although this effect was more pronounced in patients in the lower fiber group. However, regardless of the amount of fiber consumed, we observed significant changes in the profile of FAs, which may reflect the positive changes in the lipids liver metabolism. Regardless of the amount of fiber consumed, patients decreased the amount of PGE2, which may indicate the lack of disease progression associated with the development of inflammation. 相似文献
58.
Justyna Romaska Tomasz Wawrzoniak Pawe Krajewski Joanna Seliga-Siwecka Natalia Brunets Izabela Lehman Renata Bokiniec Ewa Adamska Barbara Krlak-Olejnik Jan Modzelewski Tomasz Szczapa 《Nutrients》2022,14(22)
Very preterm infants are usually supported by parenteral nutrition delivered through central lines (CLs) while progressing with enteral intake, although the optimal time point for their removal is unclear. This study evaluated the impact of the CL discontinuation time on the short-term growth outcomes of preterm infants. A non-inferiority, parallel-group, randomized controlled trial was conducted in four neonatal intensive care units in Poland. Preterm infants with very low birth weight (VLBW) without congenital abnormalities were eligible. Patients were allocated to discontinue central access at an enteral feeding volume of 100 mL/kg/day (intervention group) or 140 mL/kg/day (control group). The study’s primary outcome was weight at 36 weeks’ postmenstrual age, with a non-inferiority margin of −210 g. Overall, 211 patients were allocated to the intervention or control groups between January 2019 and February 2021, of which 101 and 100 were eligible for intention-to-treat analysis, respectively. The mean weight was 2232 g and 2200 g at 36 weeks’ postmenstrual age in the intervention and control groups, respectively. The mean between-group difference was 32 g (95% confidence interval, −68 to 132; p = 0.531), which did not cross the specified margin of non-inferiority. No intervention-related adverse events were observed. Early CL removal was non-inferior to the standard type for short-term growth outcomes in VLBW infants. 相似文献
59.
Iwona Bojar Dorota Raczkiewicz Mariusz Gujski Ewa Humeniuk Artur Wdowiak Alfred Owoc Jarosaw Pinkas 《Archives of Medical Science》2022,18(5):1318
IntroductionA potential way to explain the relationships between sleep disorders and cognitive disorders during menopausal transition is the identification of genetic markers related to changes in cognitive functions, as well as changes in quality of sleep during menopause. The objective was an analysis of the relationship between sleep disorders and cognitive disorders, according to the possessed oestrogen receptor α gene polymorphism (ESR1) in perimenopausal and postmenopausal women.Material and methodsThe study included 300 women aged 44–66 years, employed as non-manual workers. A computerised battery of the Central Nervous System Vital Signs (CNS VS) test was used to diagnose cognitive functions. ESR1 polymorphisms were genotyped using PCR-RFLP methods. The Athens Insomnia Scale was used to diagnose sleep disorders.ResultsMore severe insomnia was related to worse complex memory, visual memory, and simple attention in the total group of examined women. More severe insomnia was related to worse simple attention in women with genotypes AG Xba I or TC Pvu II ESR1, in perimenopausal women with genotypes AG Xba I or TC Pvu II ESR1. During the postmenopausal period, the severity of insomnia negatively correlated with visual memory in carriers of Pvu II TT, and with reaction time in carriers of Xba I AA.ConclusionsThe results indicate an important role of oestrogen receptor α gene polymorphism in the modulation of the effect of insomnia on cognitive functions in peri- and postmenopausal women. 相似文献
60.
Aleksandra Kukulska Jolanta Krajewska Marzena Gawkowska Ewa Paliczka-Cieslik Daria Handkiewicz-Junak Aleksandra Kropiska Zbigniew Puch Tomasz Olczyk Jozef Roskosz Barbara Jarzab 《Archives of Medical Science》2022,18(5):1241
IntroductionThe aim of this prospective study was to evaluate long-term outcomes in differentiated thyroid cancer (DTC) patients postoperatively treated with distinct RAI activities of 30 mCi, 60 mCi, and 100 mCi.Material and methodsThe analysis involved 277 low-risk and 46 intermediate-risk patients, who underwent radioiodine (RAI) ablation with 30 mCi, 60 mCi or 100 mCi under prospective, randomized clinical trials. Seventy-eight patients from the low-risk group received 30 mCi, whereas 125 and 74 patients received 60 mCi and 100 mCi, respectively. Regarding the intermediate-risk group, 20 patients were given 60 mCi, and 26 subjects were given 100 mCi. The mean time of follow-up was 11 years.ResultsAn excellent treatment response was obtained in 88%, 89% and 90% of low-risk patients treated with 30 mCi, 60 mCi, and 100 mCi, respectively, and in 85% of intermediate-risk patients, who were administered 60 or 100 mCi. An indeterminate response was achieved in 9.4% and 6.5%, whereas an incomplete structural response was obtained in 1.4% and 6.5% of low-risk and intermediate-risk patients, respectively. An incomplete biochemical response was observed only in 2.2% of intermediate-risk patients. The differences in treatment response regarding RAI activity were not significant.ConclusionsRAI activity of 30 mCi demonstrates a comparable efficacy as 60 mCi and 100 mCi in low-risk DTC. RAI activity of 60 mCi seems to be effective in intermediate-risk DTC. 相似文献