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Journal of Digital Imaging - Cardiovascular diseases (CVDs) are the top ten leading causes of death worldwide. Atherosclerosis disease in the arteries is the main cause of the CVD, leading to...  相似文献   
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External influence is essential for any change to occur in this world. Similarly, the reaction path of a chemical reaction can be changed with the addition of a catalyst from outside. Sometimes a catalyst performs better when it remains associated with an inert substance, which is called a support material (SM). Improved catalyst accomplishment arises from the ‘proximity effect’. Even inert supports play a role in better product formulation or environmental remediation. In this review, it has been shown how the SM, as a nest, aids the catalyst particle synergistically to perform a good job in a chemical reaction. The structure–function relationship of SM helps in catalyst activation to some extent, and produces active centres that are difficult to fully ascertain. In the text, Langmuir–Hinshelwood (L–H), Mars-van Krevelen (MVK), and Eley–Rideal (E–R) mechanisms are highlighted for the adsorption processes as the case may be. Again, the importance of SM for both catalyst and substrates has been consolidated here in the text. Finally, the role of the initiator and the promoter is also discussed in this review.

Catalysts are empowered with proper support materials (SM). The proximity effect, in other word ‘synergism’ between the two, is still necessary to be explored at the molecular level to revamp this never ending field of catalysis.  相似文献   
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Background:Functional brace application for isolated humeral shaft fracture persistently yields good results. Nonunion though uncommon involves usually the proximal third shaft fractures. Instead of polyethylene bivalve functional brace four plaster sleeves wrapped and molded with little more proximal extension expected to prevent nonunion of proximal third fractures. Periodic compressibility of the cast is likely to yield a better result. This can be applied on the 1st day of the presentation as an outpatient basis. Comprehensive objective scoring system befitting for fracture humeral shaft is a need.Results:The results were assessed using 100 point scoring system where union allotted 30 points and 60 points allotted for angulations (10), elbow motion (10), shoulder abduction (10), shortening (5), rotation (5), absence of infection (10), absence of nerve palsy during treatment (10). Remaining 10 points were allotted for five items with two points each. They were the absence of skin sore, absence of vascular problem, absence of reflex sympathetic dystrophy (RSD), recovery of paralyzed nerve during injury and recovery of paralyzed nerve during treatment. Results were considered excellent with 90 and above, good with 80–89, fair with 70–79 and poor below 70 point. Results at 6 months were excellent in 43.94% (n = 29), good in 42.42% (n = 28), fair in 9.1% (n = 6), poor in 4.55% (n = 3). Union took place in 98.48% (n = 65) with an average of 10.3 weeks (range 6–16 weeks). 87.5% (n = 7) paralyzed radial nerve recovered. All wounds healed. Four patients had transient skin problem. One patient with mid shaft fracture had nonunion due to the muscle interposition.Conclusion:Modified functional cast brace is one of the options in treatment for humeral shaft fractures as it can be applied on the 1st day of the presentation in most of the situations. Simple objective scoring system was useful particularly in uneducated patients.  相似文献   
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Background

Medical errors are being detected with increasing frequency in healthcare environment, in many cases leading to patient harm. Measurement and improvement of patient safety climate has been identified as a strategic effort towards addressing this vital issue.

Method

Safety Attitude Questionnaire (SAQ), validated by previous research was administered to 300 respondents in three tertiary care hospitals of India, the respondents representing various categories of healthcare workers and variations in safety scale score was analyzed by various statistical tools.

Results

No variation was observed in the Patient Safety Index score among the study hospitals. However, significant variations were observed among different categories of healthcare workers across dimensions of Teamwork, Perception of Management and Stress Recognition. Multiple Regression models identified Teamwork and Perception of Management to have significant correlation with Patient Safety Index Score.

Conclusion

Patient Safety Climate can be effectively assessed and such assessment utilized for focused improvement efforts towards safety in healthcare organizations.  相似文献   
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Stimulating stem cell differentiation without growth factor supplement offers a potent and cost-effective scaffold for tissue regeneration. We hypothesise that surface precipitation of nano-hydroxyapatite (nHAp) over blends of non-mulberry silk fibroin with better hydrophilicity and RGD amino acid sequences can direct the stem cell towards osteogenesis. This report focuses on the fabrication of a blended eri–tasar silk fibroin nanofibrous scaffold (ET) followed by nHAp deposition by a surface precipitation (alternate soaking in calcium and phosphate solution) method. Morphology, hydrophilicity, composition, and the thermal and mechanical properties of ET/nHAp were examined by field emission scanning electron microscopy, TEM, FT-IR, X-ray diffraction, TGA and contact angle measurement and compared with ET. The composite scaffold demonstrated improved thermal stability and surface hydrophilicity with an increase in stiffness and elastic modulus (778?±?2.4?N/m and 13.1?±?0.36?MPa) as compared to ET (160.6?±?1.34?N/m and 8.3?±?0.4?MPa). Mineralisation studies revealed an enhanced and more uniform surface deposition of HAp-like crystals, while significant differences in cellular viability and attachment were observed through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and confocal microscopy study. The cell viability and expression of adhesion molecules (CD 44 and CD 29) are found to be optimum for subsequent stages of growth proliferation and differentiation. The rates of proliferation have been observed to decrease owing to the transition of MSC from a state of proliferation to a state of differentiation. The confirmation of improved osteogenic differentiation was finally verified through the alkaline phosphatase assay, pattern of gene expression related to osteogenic differentiation and morphological observations of differentiated cord blood human mesenchymal stem cells under fluorescence microscope. The results obtained showed the improved physicochemical and biological properties of the ET/nHAp scaffold for osteogenic differentiation without the addition of any growth factors.  相似文献   
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