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261.
Background
Gastrointestinal stromal tumour (GIST) has many modes of presentation. This is the first reported GIST presenting as an acute abdomen. 相似文献262.
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El Sayed KA Yousaf M Hamann MT Avery MA Kelly M Wipf P 《Journal of natural products》2002,65(11):1547-1553
Microbial and chemical transformation studies of the marine sesquiterpene phenols (S)-(+)-curcuphenol (1) and (S)-(+)-curcudiol (2), isolated from the Jamaican sponge Didiscus oxeata, were accomplished. Preparative-scale fermentation of 1 with Kluyveromyces marxianus var. lactis (ATCC 2628) has resulted in the isolation of six new metabolites: (S)-(+)-15-hydroxycurcuphenol (3), (S)-(+)-12-hydroxycurcuphenol (4), (S)-(+)-12,15-dihydroxycurcuphenol (5), (S)-(+)-15-hydroxycurcuphenol-12-al (6), (S)-(+)-12-carboxy-10,11-dihydrocurcuphenol (7), and (S)-(+)-12-hydroxy-10,11-dihydrocurcuphenol (8). Fourteen-days incubation of 1 with Aspergillus alliaceus (NRRL 315) afforded the new compounds (S)-(+)-10beta-hydroxycurcudiol (9), (S)-(+)-curcudiol-10-one (10), and (S)-(+)-4-[1-(2-hydroxy-4-methyl)phenyl)]pentanoic acid (11). Rhizopus arrhizus (ATCC 11145) and Rhodotorula glutinus (ATCC 15125) afforded (S)-curcuphenol-1alpha-D-glucopyranoside (12) and (S)-curcudiol-1alpha-D-glucopyranoside (13) when incubated for 6 and 8 days with 1 and 2, respectively. The absolute configuration of C(10) and C(11) of metabolites 7-9 was established by optical rotation computations. Reaction of 1 with NaNO(2) and HCl afforded (S)-(+)-4-nitrocurcuphenol (14) and (S)-(+)-2-nitrocurcuphenol (15) in a 2:1 ratio. Acylation of 1 and 2 with isonicotinoyl chloride afforded the expected esters (S)-(+)-curcuphenol-1-O-isonicotinate (16) and (S)-(+)-curcudiol-1-O-isonicotinate (17), respectively. Curcuphenol (1) shows potent antimicrobial activity against Candida albicans, Cryptococcus neoformans, methicillin-resistant Staphylococcus aureus, and S. aureus with MIC and MFC/MBC ranges of 7.5-25 and 12.5-50 microg/mL, respectively. Compounds 1 and 3 also display in vitro antimalarial activity against Palsmodium falciparium (D6 clone) with MIC values of 3600 and 3800 ng/mL, respectively (selectivity index >1.3). Both compounds were also active against P. falciparium (W2 clone) with MIC values of 1800 (S.I. >2.6) and 2900 (S.I. >1.6) ng/mL, respectively. Compound 14 shows anti-hepatitis B virus activity with an EC(50) of 61 microg/mL. 相似文献
264.
Zohaib Akram Khulud Abdulrahman Al‐Aali Mohammed Alrabiah Faisal Abdullah Alonaizan Tariq Abduljabbar Fatemah AlAhmari Fawad Javed Fahim Vohra 《Reviews in medical virology》2019,29(3)
The pathological role of human herpesviruses (HHVs) (Epstein‐Barr virus [EBV], Human cytomegalovirus [CMV], and Herpes simplex virus [HSV]) in peri‐implant health needs clarification quantitatively. To determine the weight of evidence for HHVs in patients with peri‐implantitis (PI) and substantiate the significance of HHVs in peri‐implant inflammation, electronic databases including EMBASE, MEDLINE, Cochrane Oral Health Group Trials Register, and Cochrane Central Register of Controlled Trials were searched from 1964 up to and including November 2018. Meta‐analyses were conducted for prevalence of HHVs in PI and healthy controls. Forest plots were generated that recorded risk difference (RD) of outcomes and 95% confidence intervals (CI). Five clinical studies were considered and included. Four clinical studies reported data on EBV while three clinical studies reported data on CMV. Considering the risk of these viruses in PI, significant heterogeneity for CMV (χ2 = 53.37, p < 0.0001, I2 = 96.25%) and EBV (χ2 = 14.14, p = 0.002, I2 = 78.79%) prevalence was noticed between PI and healthy control sites. The overall RD for only EBV (RD = 0.20, 95% CI, 0.01‐0.40, p = 0.03) was statistically significant between both groups. Frequencies of the viruses were increased in patients with PI compared with healthy nondiseased sites. However, the findings of the present study should be interpreted with caution because of significant heterogeneity and small number of included studies. 相似文献
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ObjectiveTo characterize and investigate efficacy of loading functionalized ZrO2 nanoparticles in 3-dimensional (3D) printed acrylate ester-based resin subjected to accelerated aging in artificial saliva. As well as to evaluate the effect of ZrO2 nanoparticle volume fraction addition on mechanical and physical properties of printed composite.MethodsFunctionalized ZrO2 nanoparticles were characterized using TEM and Raman spectroscopy. 3D printed dental resin was reinforced, with ZrO2 nanoparticles, in the concentration range (0–5 wt.%). The resulted nanocomposites, in term of structure and physical/mechanical properties were evaluated using different mechanical testing, microscopic and spectroscopic techniques.ResultsZrO2 based nanocomposite was successful and formed composites were more ductile. Degree of conversion was significant at the highest level with blank resin and 1 wt.%. Sorption revealed reduction associated with volume fraction significant to neat resin, however solubility indicated neat and 4 wt.% had the lowest significant dissolution. Vickers represented critical positive correlation with filler content, while nanohardness and elasticity behaved symmetrically and had the maximum strength at 3 wt.% addition. In addition, 3 wt.% showed the highest fracture toughness and modulus. Improvement of flexural strength was significantly linked to filler concentration. Overall properties dramatically were enhanced after 3 months aging in artificial saliva, especially degree of conversion, microhardness, nanoindentation/elasticity, and flexural modulus. However, significant reduction was observed with flexural modulus and fracture toughness.SignificanceThe outcomes suggest that the newly developed 3D printed nanocomposites modified with ZrO2 nanoparticle have the superior potential and efficacy as long-term provisional dental restoration materials. 相似文献
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268.
Assessment of interleukin‐1β, interleukin‐6, and tumor necrosis factor‐Α levels in the peri‐implant sulcular fluid among waterpipe (narghile) smokers and never‐smokers with peri‐implantitis
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269.
Peri‐implant conditions and levels of advanced glycation end products among patients with different glycemic control
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270.