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21.
AIM: In node-negative breast cancer patients, several factors for survival have been evaluated and currently, some of them are accepted for their prognostic and/or predictive values after validation in the separate data sets. The prognostic significance of increases in the number of pathologically detectable axillary lymph nodes in the node-negative patients could not been established clearly. To address this question, we have reviewed our patients' records. METHODS: A retrospective cohort study was conducted in pathologically node-negative patients who underwent modified radical mastectomy for stage I and II breast cancer. Survival and multivariate prognostic factor analyses were carried out to determine whether the number of tumour-free lymph nodes in complete axillary dissection material in addition to known factors was significant for the outcomes. RESULTS: Two hundred and seventy consecutive patients were eligible to enter the trial. The median observation time and the median number of tumour-free lymph nodes were 61 (from 30 to 120) months and 18 (from 10 to 44), respectively. The cohort was divided into the groups according to the number of nodes. The 5-year event-free and overall survivals were 92.5 and 98.3% for patients who had 18 lymph nodes or less, and 70 and 86.7% for those who had more than 18 negative nodes, respectively (P < 0.00001). Multivariate analysis for event-free survival demonstrated that the number of lymph nodes (Relative risk: 3.2 and 95% confidence interval: 1.7 to 5.9) in addition to the pathological tumour size and age was the most important independent prognosticator. In similar, multivariate analysis for overall survival showed that the number of lymph nodes together with the tumour size was the significant indicator (RR of cancer-specific dying in patients who had more than 18 nodes: 3.1 and 95% CI: 1.2 to 8.5). CONCLUSION: The increases in number of tumour-free lymph nodes are clinically important and this parameter should be taken into consideration in the breast cancer patients without metastatic lymph nodes.  相似文献   
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BACKGROUND: On February 19, 2003, four patients (patients 1-4) in the neurology ward underwent cranial magnetic resonance angiography (MRA) and developed fever within 1 hour afterward. Klebsiella oxytoca was isolated from blood cultures of patients 1 through 3. OBJECTIVE: To identify the source of this cluster of nosocomial K. oxytoca bloodstream infections. DESIGN: Outbreak investigation. SETTING: A 1,000-bed university hospital. METHODS: The infection control team reviewed patient charts and interviewed nursing staff about the preparation and administration of parenteral fluids. The procedure of cranial MRA was observed. Arbitrarily primed polymerase chain reaction (AP-PCR) was performed to show the clonal relationship among these three strains. RESULTS: AP-PCR revealed that three K. oxytoca isolates had the same molecular profile. Cranial MRA was found to be the only common source among these patients. During MRA, before injection of the contrast medium, normal saline solution was infused to check the functioning of the intravenous catheter. Use of the solution for multiple patients was routine, but the access diaphragm of the bottle was not cleansed. The bottle of normal saline solution used on February 19 had already been discarded and the culture sample taken from the solution on the day of observation was sterile. CONCLUSIONS: We speculate that normal saline solution became contaminated during manipulation and that successive uses might have been responsible for this cluster. Poor aseptic techniques employed during successive uses appear to be the most likely route of contamination. Use of parenteral solutions for multiple patients was discontinued.  相似文献   
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To evaluate diagnostic efficacy of transvaginal saline infusion sonohysterography (TV-SHG) in the evaluation of uterine cavities in tamoxifen (TAM) administered asymptomatic postmenopausal breast cancer patients with increased endometrial thickness, sixty asymptomatic postmenopausal breast cancer women receiving adjuvant TAM treatment for at least 6 months and with endometrial thickness’ ≥5 mm measured in transvaginal ultrasonography (TVS) were enrolled. Each patient underwent TV-SHG, followed by outpatient hysteroscopy (HYS) with endometrial biopsy. TV-SHG application was accepted as unsuccessful in four cases (6.7%). When office HYS combined biopsy was considered as gold standard, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of TV-SHG were estimated as 90%, 100%, 100%, and 95%, respectively. Our findings showed that TV-SHG was a valuable diagnostic tool in the evaluation of uterine cavities of TAM administered asymptomatic postmenopausal patients having an increased endometrial thickness.  相似文献   
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GM1 gangliosidosis is an autosomal recessive glycosphingolipid storage disease caused by defects in the enzyme beta-galactosidase. Three clinical forms (infantile-, juvenile-, and adult-onset) of the disease are recognized. Patients with infantile GM1 gangliosidosis present at birth or shortly thereafter with somatic and bony changes, followed by severe neurological deterioration ultimately leading to death within the first 2 years of life. We present the brain CT, MRI and MR spectroscopy (MRS) findings in a 17-month-old Turkish girl with infantile GM1 gangliosidosis. Neuroimaging findings in patients with infantile GM1 gangliosidosis have been reported only in a few cases. In this study, MRS of the thalamus was performed to study the metabolic changes in GM1 gangliosidosis. We showed a a decreased NAA/Cr ration and an increased Cho/Cr ratio. To our knowledge, this is the first report of magnetic resonance spectroscopy findings in type-1 GM1 gangliosidosis.  相似文献   
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Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model.  相似文献   
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Donor–acceptor (D–A) small molecules are regarded as promising hole-transporting materials for perovskite solar cells (PSCs) due to their tunable optoelectronic properties. This paper reports the design, synthesis and characterization of three novel isomeric D-π-A small molecules PY1, PY2 and PY3. The chemical structures of the molecules consist of a pyrazolo[1,5-a]pyrimidine acceptor core functionalized with one 3,6-bis(4,4′-dimethoxydiphenylamino)carbazole (3,6-CzDMPA) donor moiety via a phenyl π-spacer at the 3, 5 and 7 positions, respectively. The isolated compounds possess suitable energy levels, sufficient thermal stability (Td > 400 °C), molecular glass behavior with Tg values in the range of 127–136 °C slightly higher than that of the reference material Spiro-OMeTAD (126 °C) and acceptable hydrophobicity. Undoped PY1 demonstrates the highest hole mobility (3 × 10−6 cm2 V−1 s−1) compared to PY2 and PY3 (1.3 × 10−6 cm2 V−1 s−1). The whole isomers were incorporated as doped HTMs in planar n-i-p PSCs based on double cation perovskite FA0.85Cs0.15Pb(I0.85Br0.15)3. The non-optimized device fabricated using PY1 exhibited a power conversion efficiency (PCE) of 12.41%, similar to that obtained using the reference, Spiro-OMeTAD, which demonstrated a maximum PCE of 12.58% under the same conditions. The PY2 and PY3 materials demonstrated slightly lower performance in device configuration, with relatively moderate PCEs of 10.21% and 10.82%, respectively, and slight hysteresis behavior (−0.01 and 0.02). The preliminary stability testing of PSCs is also described. The PY1-based device exhibited better stability than the device using Spiro-OMeTAD, which could be related to its slightly superior hydrophobic character preventing water diffusion into the perovskite layer.  相似文献   
29.
BackgroundThe failure rate of vascular closure devices remains a significant cause of major vascular complications in contemporary transcatheter aortic valve implantation practice.MethodsThis research aimed to evaluate use of the Angio-Seal device in a bailout context in the setting of incomplete hemostasis following use of dual Perclose ProGlide devices in patients undergoing transfemoral transcatheter aortic valve implantation. A total of 185 patients undergoing transfemoral transcatheter aortic valve implantation with either dual Per-close ProGlide (n = 139) or a combination of dual Perclose ProGlide and Angio-Seal (n = 46) were retrospectively analyzed. The baseline, procedural characteristics, and all outcomes (defined according to Valve Academic Research Consortium-2 criteria) were compared.ResultsNo significant differences were seen between the dual Perclose ProGlide vs dual Perclose ProGlide+Angio-Seal groups with regard to the in-hospital Valve Academic Research Consortium-2 primary end points of major vascular complications (n = 13 [9.4%] vs n = 2 [4.3%]; P = .36), minor vascular complications (n = 13 [9.4%] vs n = 8 [14.7%]; P = .14), major bleeding (n = 16 [11.5%] vs n = 2 [4.3%]; P = .25), and minor bleeding (n = 9 [6.5%] vs n = 5 [10.9%]; P = .34), with higher rates of hematoma in the dual Perclose ProGlide+Angio-Seal group (n = 4 [2.9%] vs n = 5 [10.9%]; P = .044).ConclusionFinding from the current study suggest that adjunctive Angio-Seal deployment may be feasible and safe, especially in patients with incomplete hemostasis following dual Perclose ProGlide use, and can be an optimal “bailout” procedure.  相似文献   
30.
ObjectiveThe purpose of this in vitro study was to evaluate the effects of four over-the-counter (OTC) whitening products on the microhardness, surface roughness, color, shear bond strength (SBS) and surface charecteristics of human enamel compared with a product used for dentist-supervised home whitening.Materials and methodsSeventy eight enamel specimens allocated into 6 groups (n=13): 1-Opalescence PF 10% (OP) dentist prescribed home whitening product, 2-Opalescence Go prefilled tray (PT), 3-Opalescence Whitening Toothpaste (WT), 4-Listerine Healthy White whitening mouth rinse (WMR), 5-Cavex Bite&White whitening pen (WP) and 6- no treatment (Con). The microhardness (VHN), surface roughness (Ra) and color of the specimens were measured (T0). The specimens were then subjected to whitening protocols for 14 days (T1.) followed by artificial saliva storage for 14 days (T2). The measurements were repeated at T1 and T2. The SBS test was done after the application of 35% phosphoric acid (Scotchbond Universal Etchant), followed by a universal adhesive (G-Premio Bond) and a micro hybrid/universal resin composite (Essentia) into a Teflon tube attached to the enamel surface (p<0.05). Surface morphologies of the enamel surfaces were examined by SEM. p value was set at 0.05ResultsApplication of OP, PT and WP decrased the microhardness of enamel specimens (p<0.05) whereas, no significant changes were seen in the microhardness of enamel specimens treated with WT and WMR (p>0.05). Ra values of enamel specimens increased with the application of OP, PT and WT (p<0.05); whereas no changes were observed after the applications of WMR and WP (p>0.05). OP, PT, WMR, and WP changed the color of the enamel(p<0.05). There were not any significant differences among the SBSs groups, apart from OP applied enamel specimens. OP showed the least SBS values (p=0.001). SEM observations revealed smooth enamel surfaces.ConclusionsThe whitening products affected the microhardness, surface roughness, color of enamel differently. Only OP decreased the SBS of the enamel.  相似文献   
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