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排序方式: 共有2043条查询结果,搜索用时 31 毫秒
91.
Matthias May Luca Cindolo Richard Zigeuner Ottavio De Cobelli Bernardo Rocco Cosimo De Nunzio Andrea Tubaro Ioman Coman Michael Truss Orietta Dalpiaz Ingmar Wolff Bogdan Feciche Fabian Fenske Martin Pichler Luigi Schips Robert S. Figenshau Kerry Madison Manuel Sánchez-Chapado Sabine Brookman-May 《Urologic oncology》2014,32(8):1252-1258
ObjectivesTo analyze clinicopathological features and survival of surgically treated patients with renal cell carcinoma (RCC)≥80 years of age in comparison with patients between the ages of 60 and 70 years.Materials and methodsThe data for 2,516 patients with a median follow-up of 57 months were retrieved from a multinational database (Collaborative Research on Renal Neoplasms Association [CORONA]), including data for 6,234 consecutive patients with RCC after radical or partial nephrectomy. Comparative analysis of clinicopathological features of 241 octogenarians (3.9% of the database) and 2,275 reference patients between the ages of 60 and 70 years (36.5%) was performed. Multivariable regression analysis adjusted for competing risks was applied to identify the effect of advanced age on cancer-specific mortality (CSM) and other-cause mortality (OCM). Furthermore, instrumental variable analysis was employed to reduce residual confounding by unmeasured parameters.ResultsSignificantly more women were present (50% vs. 40%, P = 0.004), and significantly less often nephron-sparing surgery was performed in octogenarians compared with the reference group (11% vs. 20%, P<0.001). Although median tumor size and stages did not significantly defer, older patients less often had advanced or metastatic disease (N+/M1) (4.6% vs. 9.6%, P = 0.009). On multivariable analysis, higher CSM (hazard ratio = 1.48, P = 0.042) and OCM rates (hazard ratio = 4.32, P<0.001) were detectable in octogenarians (c-indices = 0.85 and 0.72, respectively). Integration of the variable age group in multivariable models significantly increased the predictive accuracy regarding OCM (6%, P<0.001), but not for CSM. Limitations are based on the retrospective study design.ConclusionsOctogenarian patients with RCC significantly differ in clinical features and display significantly higher CSM and OCM rates in comparison with their younger counterparts. 相似文献
92.
David Chiapaikeo Molly Schultheis Bogdan Protyniak Paul Pearce Frank J. Borao Steven J. Binenbaum 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2014,18(4)
Background and Objectives:
Laparoscopic adjustable gastric banding is considered the least invasive surgical option for the treatment of morbid obesity. Its initial popularity has been marred by recent long-term studies showing high complication rates. We sought to examine our experience with gastric banding and factors leading to reoperation.Methods:
We reviewed retrospective data of 305 patients who underwent laparoscopic adjustable gastric banding between 2004 and 2011 at a single institution, 42 patients of whom required a reoperation, constituting 13.8%. Patients undergoing elective reoperations for port protrusion from weight loss as a purely cosmetic issue were excluded (n = 10). Patients'' demographic data, weight loss, time to reoperation, and complications were analyzed.Results:
Of 305 patients, 42 (13.8%) required reoperations: 26 underwent band removal (8.5%) and 16 underwent port revision (5.2%). The mean weight and body mass index for all patients who underwent reoperations were 122.6 kg and 45.0 kg/m2, respectively. The most common complication leading to band removal was gastric prolapse (n = 14, 4.6%). The most common indication for port revision was a nonfunctioning port (n = 10, 3.3%).Conclusion:
Laparoscopic adjustable gastric banding was initially popularized as a minimally invasive gastric-restrictive procedure with low morbidity. Our study showed a 13.8% reoperation rate at 3 years'' follow-up. Most early reoperations (<2 years) were performed for port revision, whereas later reoperations (>2 years) were likely to be performed for band removal. Laparoscopic adjustable gastric banding is associated with high reoperation rates; therefore bariatric surgeons should carefully consider other surgical weight-loss options tailored to the needs of the individual patient that may have lower complication and reoperation rates. 相似文献93.
94.
Background
In utero exposure to arsenic is known to adversely affect reproductive outcomes. Evidence of arsenic teratogenicity varies widely and depends on individual genotypic differences in sensitivity to As. In this study, we investigated the potential interaction between 5,10-methylenetetrahydrofolate reductase (Mthfr) genotype and arsenic embryotoxicity using the Mthfr knockout mouse model.Methods
Pregnant dams were treated with sodium arsenate, and reproductive outcomes including: implantation, resorption, congenital malformation and fetal birth weight were recorded at E18.5.Results
When the dams in Mthfr+/− × Mthfr+/− matings were treated with 7.2 mg/kg As, the resorption rate increased to 43.4%, from a background frequency of 7.2%. The As treatment also induced external malformations (40.9%) and significantly lowered the average fetal birth weight among fetuses, without any obvious toxic effect on the dam. When comparing the pregnancy outcomes resulting from different mating scenarios (Mthfr+/+ × Mthfr+/−, Mthfr+/− × Mthfr+/− and Mthfr−/− × Mthfr+/−) and arsenic exposure; the resorption rate showed a linear relationship with the number of null alleles (0, 1 or 2) in the Mthfr dams. Fetuses from nullizygous dams had the highest rate of external malformations (43%) and lowest average birth weight. When comparing the outcomes of reciprocal matings (nullizygote × wild-type versus wild-type × nullizygote) after As treatment, the null dams showed significantly higher rates of resorptions and malformations, along with lower fetal birth weights.Conclusions
Maternal genotype contributes to the sensitivity of As embryotoxicity in the Mthfr mouse model. The fetal genotype, however, does not appear to affect the reproductive outcome after in utero As exposure. 相似文献95.
Bogdan Stefan Vasile Ovidiu Oprea Georgeta Voicu Anton Ficai Ecaterina Andronescu Andrei Teodorescu Alina Holban 《International journal of pharmaceutics》2014
Freshly prepared ZnO nanoparticles were incorporated into a chitosan solution in weight ratios ranging from 1:1 to 12:1. Starting from the ratio of 3:1 the chitosan solution was transformed into a gel with a high consistency, which incorporates 15 mL water for only 0.1 g solid substance. The powders obtained after drying the gel were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermal analysis (TG-DSC). The electronic (UV–vis), infrared (FTIR) and photoluminescence (PL) spectra were also recorded. ZnO particles were coated with gentamicin and incorporated into the chitosan matrix, to yield a ZnO/gentamicin–chitosan gel. The release rate of gentamicin was monitored photometrically. This ZnO/gentamicin–chitosan gel proved great antimicrobial properties, inhibiting Staphylococcus aureus and Pseudomonas aeruginosa growth in both planktonic and surface-attached conditions. The results indicate that the obtained composite can be used in cutaneous healing for developing improved wound dressings, which combine the antibacterial activity of all three components with the controlled release of the antibiotic. This wound dressing maintains a moist environment at the wound interface, providing a cooling sensation and soothing effect, while slowly releasing the antibiotic. The system is fully scalable to any other soluble drug, as the entire solution remains trapped in the ZnO–chitosan gel. 相似文献
96.
Alexandru Mihai Grumezescu Cristina Daniela Ghitulica Georgeta Voicu Keng-Shiang Huang Chih-Hui Yang Anton Ficai Bogdan Stefan Vasile Valentina Grumezescu Coralia Bleotu Mariana Carmen Chifiriuc 《International journal of pharmaceutics》2014
In this paper, we report the synthesis, characterization (FT-IR, XRD, BET, HR-TEM) and bioevaluation of a novel γ-aminobutiric acid/silica (noted GABA-SiO2 or γ-SiO2) hybrid nanostructure, for the improved release of topical antibiotics, used in the treatment of Staphylococcus aureus infections. GABA-SiO2 showed IR bands which were assigned to Si–O–Si (stretch mode). The XRD pattern showed a broad peak in the range of 18–30° (2θ), indicating an amorphous structure. Based on the BET analysis, estimations about surface area (438.14 m2/g) and pore diameters (4.76 nm) were done. TEM observation reveals that the prepared structure presented homogeneity and an average size of particles not exceeding 10 nm. The prepared nanostructure has significantly improved the anti-staphylococcal activity of bacitracin and kanamycin sulfate, as demonstrated by the drastic decrease of the minimal inhibitory concentration of the respective antibiotics loaded in the GABA-SiO2 nanostructure. These results, correlated with the high biocompatibility of this porous structure, are highlighting the possibility of using this carrier for the local delivery of the antimicrobial substances in lower active doses, thus reducing their cytotoxicity and side-effects. 相似文献
97.
Tomasz Trzepieciski Andrzej Kubit Andrzej Dzierwa Bogdan Krasowski Wojciech Jurczak 《Materials》2021,14(7)
The article presents the results of the analysis of the interactions between the single point incremental forming (SPIF) process parameters and the main roughness parameters of stiffened ribs fabricated in Alclad aluminium alloy panels. EN AW-7075-T6 and EN AW-2024-T3 Alclad aluminium alloy sheets were used as the research material. Panels with longitudinal ribs were produced with different values of incremental vertical step size and tool rotational speed. Alclad is formed of high-purity aluminium surface layers metallurgically bonded to aluminium alloy core material. The quality of the surface roughness and unbroken Alclad are key problems in SPIF of Alclad sheets destined for aerospace applications. The interactions between the SPIF process parameters and the main roughness parameters of the stiffened ribs were determined. The influence of forming parameters on average roughness Sa and the 10-point peak–valley surface roughness Sz was determined using artificial neural networks. The greater the value of the incremental vertical step size, the more prominent the ridges found in the inner surface of stiffened ribs, especially in the case of both Alclad aluminium alloy sheets. The predictive models of ANNs for the Sa and the Sz were characterised by performance measures with R2 values lying between 0.657 and 0.979. A different character of change in surface roughness was found for sheets covered with and not covered with a soft layer of technically pure aluminium. In the case of Alclad sheets, increasing the value of the incremental vertical step size increases the value of the surface roughness parameters Sa and Sz. In the case of the sheets not covered by Alclad, reduction of the tool rotational speed increases the Sz parameter and decreases the Sa parameter. An obvious increase in the Sz parameter was observed with an increase in the incremental vertical step size. 相似文献
98.
Sajjad Mohsin I. Rayyif Hamzah Basil Mohammed Carmen Curuiu Alexandra Ctlina Bîrc Alexandru Mihai Grumezescu Bogdan tefan Vasile Lia Mara Diu Veronica Lazr Mariana Carmen Chifiriuc Grigore Mihescu Alina Maria Holban 《Materials》2021,14(11)
Zinc oxide (ZnO) nanoparticles (NPs) have been investigated for various skin therapies in recent years. These NPs can improve the healing and modulate inflammation in the wounds, but the mechanisms involved in such changes are yet to be known. In this study, we have designed a facile ZnO nano-coated dressing with improved antimicrobial efficiency against typical wound pathogens involved in biofilm and chronic infections. ZnO NPs were obtained by hydrothermal method and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Fourier-transform infrared spectroscopy. Antibacterial and antibiofilm effects were evaluated against laboratory and clinical isolates of significant Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) opportunistic pathogens, by quantitative methods. Our results have shown that the developed dressings have a high antibacterial efficiency after 6–24 h of contact when containing 0.6 and 0.9% ZnO NPs and this effect is similar against reference and clinical isolates. Moreover, biofilm development is significantly impaired for up to three days of contact, depending on the NPs load and microbial species. These results show that ZnO-coated dressings prevent biofilm development of main wound pathogens and represent efficient candidates for developing bioactive dressings to fight chronic wounds. 相似文献
99.
Barbara Przybylska-Gornowicz Micha? Tarasiuk Bogdan Lewczuk Magdalena Prusik Natalia Zió?kowska ?ukasz Zielonka Maciej Gaj?cki Magdalena Gaj?cka 《Toxins》2015,7(11):4684-4705
Immature gilts were administered per os with zearalenone (ZEN) at 40 μg/kg BW (group Z, n = 9), deoxynivalenol (DON) at 12 μg/kg BW (group D, n = 9), a mixture of ZEN and DON (group M, n = 9) or a placebo (group C, n = 9) over a period of six weeks. The pigs were sacrificed after one, three, or six weeks of the treatment (12 pigs per each time-point). Histological investigations revealed an increase in the mucosal thickness and the crypt depth as well as a decrease in the ratio of the villus height to the crypt depth in groups D and M after six weeks of exposure to the mycotoxins. The number of goblet cells in the villus epithelium was elevated in groups Z and M after one week and in group D after three weeks. The administration of ZEN increased the lymphocyte number in the villus epithelium after 1 week and the plasma cell quantity in the lamina propria after one, three, and six weeks of the experiment. DON treatment resulted in an increase in the lymphocyte number in the villus epithelium and the lamina propria after six weeks, and in the plasma cell quantity in the lamina propria after one, three, and six weeks of exposure. In group M, lymphocyte counts in the epithelium and the lamina propria increased significantly after six weeks. Neither mycotoxin induced significant adverse changes in the ultrastructure of the mucosal epithelium and the lamina propria or in the intestinal barrier permeability. Our results indicate that immune cells are the principal target of low doses of ZEN and DON. 相似文献
100.
Maria Luisa Grilli Daniele Valerini Anca Elena Slobozeanu Bogdan O. Postolnyi Sebastian Balos Antonella Rizzo Radu Robert Piticescu 《Materials》2021,14(7)
Several applications, where extreme conditions occur, require the use of alloys often containing many critical elements. Due to the ever increasing prices of critical raw materials (CRMs) linked to their high supply risk, and because of their fundamental and large utilization in high tech products and applications, it is extremely important to find viable solutions to save CRMs usage. Apart from increasing processes’ efficiency, substitution, and recycling, one of the alternatives to preserve an alloy and increase its operating lifetime, thus saving the CRMs needed for its manufacturing, is to protect it by a suitable coating or a surface treatment. This review presents the most recent trends in coatings for application in high temperature alloys for aerospace engines. CRMs’ current and future saving scenarios in the alloys and coatings for the aerospace engine are also discussed. The overarching aim of this paper is to raise awareness on the CRMs issue related to the alloys and coating for aerospace, suggesting some mitigation measures without having the ambition nor to give a complete overview of the topic nor a turnkey solution. 相似文献