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61.
Clinical and Experimental Medicine - The luminal-A-like and luminal-B-like breast cancer groups have distinct biological features that lead to differences in the treatment response and clinical...  相似文献   
62.
Effects of long-term application of novel polyphenolic composition BP-C3, containing polyphenolic benzenepolycarboxylic acids, vitamins and minerals on some biomarkers of aging, life span and spontaneous tumorigenesis has been studied in female SHR mice. Administration of BP-C3 with drinking water (0.005%) did not exert any toxic effect (did not have effect on general condition of animals, weight dynamics and consumption of food), postponed age-related switch-off of estrous function, caused slight reduction of body temperature. An increased survival was observed in mice treated with BP-C3 (p=0.00164, log rank test). BP-C3 increased mean lifespan – by 8.4%, lifespan of the last 10% of animals – by 12.4%, and life span of tumor-free mice – by 11.6%. A tendency in ability of BP-C3 to inhibit development of spontaneous tumors in mice was detected, though it did not reach the level of statistical significance (p=0.166, log rank test). The number of malignant mammary tumors was 1.5 times less and total number of tumors of various localizations was 1.6 times less in BP-C3 treated animals. Multiple tumors were registered in 8% of mice in the control group and no cases – in BP-C3 treated group. Thus, BP-C3 demonstrated some anti-carcinogenic and a pronounced geroprotective activity.  相似文献   
63.
The question of the microscopic origin of the M-superstructure and additional satellite peaks in the Zr-rich lead zirconate-titanate is discussed for nearly 50 years. Clear contradiction between the selection rules of the critical scattering and the superstructure was found preventing unambiguous attributing of the observed superstructure either to the rotation of the oxygen octahedra or to the antiparallel displacements of the lead cations. Detailed analysis of the satellite pattern explained it as the result of the incommensurate phase transition rather than antiphase domains. Critical dynamics is the key point for the formulated problems. Recently, the oxygen tilt soft mode in the PbZr0.976Ti0.024O3 (PZT2.4) was found. But this does not resolve the extinction rules contradiction. The results of the inelastic X-ray scattering study of the phonon spectra of PZT2.4 around M-point are reported. Strong coupling between the lead and oxygen modes resulting in mode anticrossing and creation of the wide flat part in the lowest phonon dispersion curves is identified. This flat part corresponds to the mixture of the displacements of the lead and oxygen ions and can be an explanation of the extinction rules contradiction. Moreover, a flat dispersion surface is a typical prerequisite for the incommensurate phase transition.  相似文献   
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This study specifies the basic principles to selectively kill p53-deficient cells (H1299, FaDu) by taxol and to protect p53 wild type cells (A549) by the prior administration of structurally related flavonoids (apigenin, genistein, and quercetin). Cytotoxic and cytostatic properties of flavonoids were investigated in vitro by flow cytometry and were compared to known anticancer drugs (cisplatin, doxorubicin, etoposide). It was confirmed that doxorubicin induced growth arrest and protected A549 cells from taxol while simultaneously killing or blocking H1299 and FaDu cancer cells. It was found that doxorubicin could be successfully substituted in this way by the isoflavone genistein used at physiologically relevant concentrations. The other compounds analyzed revealed less selectivity (apigenin, cisplatin) or demonstrated higher toxicity (cisplatin, etoposide, and quercetin). We concluded that genistein-based therapy may have antagonistic effects when combined with mitotic poisons. The proposed therapeutic strategy allows protection of p53 wild type cells from taxol and selectively increases apoptosis in p53-deficient cells. This strategy exploits the naturally occurring compound that can be used without significant toxicity in rather high concentrations as present in common diets.  相似文献   
67.

Objective

Although the Ross procedure provides excellent long-term survival and a high quality of life, its use has been limited to relatively few centers. In this study, we evaluated long-term Ross procedure results in adults to assess the predictors of pulmonary autograft durability.

Methods

Between 1998 and 2015, 793 consecutive adult patients underwent the Ross procedure. The total root replacement technique was used in all patients.

Results

The early mortality rate was 2.9%. The mean follow-up duration was 6.5 ± 3.2 years, and the 10-year survival rate was 90.4%. Longitudinal mixed-effects ordinal regression identified a combination of bicuspid aortic valve and aortic insufficiency (odds ratio, 2.19; P < .001) as predictors for progression of autograft valve insufficiency at follow-up. The cumulative incidence of autograft reoperations at 10 years was 8.6%. Competing risk regression identified bicuspid aortic valve insufficiency as the independent predictor of autograft reoperation (subdistribution hazard ratio, 2.16; P = .030). Moreover, patients with bicuspid aortic valve and aortic insufficiency had greater increases in annulus (P < .001), sinus (P < .001), and ascending aorta (P < .001) diameters over time.

Conclusions

For patients undergoing the Ross procedure, a combination of bicuspid aortic valves and aortic insufficiency is the main risk factor for late autograft dilatation and dysfunction.  相似文献   
68.
Lactobacilli play a key role in promoting vaginal health. Depletion of these bacteria is associated with bacterial vaginosis (BV), the most common vaginal disorder. Here we describe the development and laboratory validation of a novel single-tube multiplex TaqMan quantitative polymerase chain reaction (qPCR) assay for the identification and quantitative assessment of the four major vaginal Lactobacillus species: L. crispatus, L. jensenii, L. gasseri, and L. iners. The assay utility was evaluated by the analysis of lactobacilli in non-cultured clinical vaginal swab specimens collected from BV patients and healthy individuals. As confirmed by the assay, L. crispatus, L. jensenii, and to a lesser extent L. gasseri, are common in the vagina of healthy women, whereas L. iners dominance is associated with BV. The major assay limitation was preferential detection of dominant Lactobacillus species in samples with mixed lactobacilli resulting in lower sensitivity for minor species. The multiplex qPCR assay described here is an advance in the detection and quantitation of the major vaginal lactobacilli, potentially facilitating the molecular diagnosis of BV and post-therapy restoration of the vaginal microflora.  相似文献   
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Digestive Diseases and Sciences - Conventional adenomas (CAs) and serrated polyps (SPs) are precursors to colorectal cancer (CRC). Understanding metachronous cancer risk is poor due to lack of...  相似文献   
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