10 research outputs found
Structure and Properties of Nano- and Microcomposite Coating Based on Ti-Si-N/WC-Co-Cr
Using the two technologies: plasma-detonation and vacuum-arc deposition, we fabricated two types of coatings: Ti-Si-N/WC-Co-Cr/steel and Ti-Si-N/steel. We found that the top coating of Ti-Si-N was nanostructured one with 12 to 15 nm grain sizes and H = 40 to 38 GPa hardness. A thick coating which was deposited using the pulsed plasma jet, demonstrated 11 to 15.3 GPa hardness, an elastic modulus (E) changing within 176 to 240 GPa, and tungsten carbide grain dimensions varying from 150 to 350 nm to several microns. An X-ray diffraction analysis shows that the coating has the following phase composition: TiN, (Ti,Si)N solid solution, WC, tungsten carbides. An element analysis was performed using energy dispersive spectroscopy (microanalysis) and scanning electron microscopy, as well as the Rutherford backscattering of ion and the Auger electron spectroscopy. Surface morphology and structure were analyzed using scanning electron microscopy and scanning tunnel microscopy. Tests friction and resistance (cylinder-plane) demonstrated essential resistance to abrasive wear and corrosion in the solution. The decrease of grain dimensions ≤ 10 nm occurring in the top Ti-Si-N coating layer increased the sample hardness to 42 ± 2.7 GPa under at.% concentration
Impact of Perioperative Blood Transfusions on the Outcomes of Patients Undergoing Kidney Cancer Surgery: A Systematic Review and Pooled Analysis
The aim of the present study is to systematically review current evidence regarding the association between perioperative blood transfusions (PBT) and oncological outcomes of patients with renal cell carcinoma undergoing nephrectomy procedures. A computerized bibliographic search was conducted to identify pertinent studies. The Population, Intervention, Comparator, Outcome (PICO) study design approach was used to define study eligibility according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) criteria. Only 7 studies were deemed fully eligible for analysis. Most series included both open and laparoscopic cases. The rate of PBT varied between 9.6% and 76.6%, and the median number of transfused units was 2 for most of the studies. At pooled analysis, a statistically significant association was found between PBT and disease recurrence (HR, 1.79; 95% CI, 1.32-2.41; P <.001), cancer-specific mortality (HR, 1.62; 95% CI, 1.29-2.05; P ≤.001), and all-cause mortality (HR, 1.45; 95% CI, 1.25-1.69; P <.001). Current evidence suggests that indeed the use of PBT may be associated with worse oncologic outcomes in patients with renal cell carcinoma undergoing nephrectomy procedures. Although presents findings should be interpreted within the intrinsic limitations of this type of pooled analysis, they emphasize the need for evidence-based strategies to minimize the use of PBT during kidney cancer surgery
Impact of Perioperative Blood Transfusions on the Outcomes of Patients Undergoing Kidney Cancer Surgery: A Systematic Review and Pooled Analysis
The aim of the present study is to systematically review current evidence regarding the association between perioperative blood transfusions (PBT) and oncological outcomes of patients with renal cell carcinoma undergoing nephrectomy procedures. A computerized bibliographic search was conducted to identify pertinent studies. The Population, Intervention, Comparator, Outcome (PICO) study design approach was used to define study eligibility according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) criteria. Only 7 studies were deemed fully eligible for analysis. Most series included both open and laparoscopic cases. The rate of PBT varied between 9.6% and 76.6%, and the median number of transfused units was 2 for most of the studies. At pooled analysis, a statistically significant association was found between PBT and disease recurrence (HR, 1.79; 95% CI, 1.32-2.41; P <.001), cancer-specific mortality (HR, 1.62; 95% CI, 1.29-2.05; P ≤.001), and all-cause mortality (HR, 1.45; 95% CI, 1.25-1.69; P <.001). Current evidence suggests that indeed the use of PBT may be associated with worse oncologic outcomes in patients with renal cell carcinoma undergoing nephrectomy procedures. Although presents findings should be interpreted within the intrinsic limitations of this type of pooled analysis, they emphasize the need for evidence-based strategies to minimize the use of PBT during kidney cancer surgery