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101.
102.
Reza Fekrazad Khojasteh Joharchi Katayoun AM Kalhori Fatemeh Mashhadi Abbas Fariborz Salimi Vahid 《Journal of cosmetic and laser therapy》2017,19(4):232-236
Introduction: One of the most important innovative methods for tissue repair promotion is therapeutic lasers with photobiomodulution effects. The aim of this study was to investigate the effect of four different wavelengths of therapeutic laser (405, 532, 660 and 810 nm) on healing of third-degree burns from both clinical and pathological standpoints in rats. Materials and methods: 60 male Wistar rats were used. Animals were anesthetized and dorsal hairs were shaved and third-degree skin burns were created by use of a 95°C copper stamp. Lesions were irradiated with 1.5 J/cm2 energy densities and 200 mW/cm2 power densities. Results: Statistical analyses of the “wound contraction” changes between five groups during the study showed more reduction in wound size in all laser groups in comparison with the control group; but these differences were not statistically significant except between red and blue lasers on the last day of experiment. Discussion: Results of our study showed that using therapeutic lasers with green, blue, red, and infrared wavelengths may accelerate healing process. This trend is more obvious in red and infrared groups especially after acute phase, however, this effect was neither statistically nor clinically significant. 相似文献
103.
Aymen S. Abu Hatab Yahia H. Ahmad Mohd B. Abdul Rahman Siham Y. Al-Qaradawi 《RSC advances》2022,12(3):1694
Oxygen evolution reaction (OER) has arisen as an outstanding technology for energy generation, conversion, and storage. Herein, we investigated the synthesis of nickel-based hybrid metal oxides (NixM1−xOy) and their catalytic performance towards OER. NixM1−xOy catalysts were synthesized by solution combustion synthesis (SCS) using the metal nitrates as oxidizer and glycine as fuel. Scanning electron microscope (SEM) micrographs display a porous morphology for the hybrid binary NixM1−xOy, the common feature of combusted materials. X-ray diffraction (XRD) of NixM1−xOy depicted well-defined diffraction peaks, which confirms the crystalline nature of synthesized catalysts. The particle size of as-synthesized materials ranges between 20 and 30 nm with a mesoporous nature as revealed by N2-physisorption. The electrocatalytic performance of the as-prepared materials was evaluated towards OER in alkaline medium. Among them, NixCo1−xOy showed the best catalytic performance. For instance, it exhibited the lowest overpotential at a current density of 10 mA cm−2 (404 mV), onset potential (1.605 V), and Tafel slope (52.7 mV dec−1). The enhanced electrocatalytic performance of NixCo1−xOy was attributed to the synergism between cobalt and nickel and the alteration of the electronic structure of nickel. Also, NixCo1−xOy afforded the highest Ni3+/Ni2+ when compared to other electrocatalysts. This leads to higher oxidation states of Ni species, which promote and improve the electrocatalytic activity.Ni-based mixed transition metal oxides (MTMO) (NixM1−xOy) were synthesized using the solution combustion synthesis (SCS), and investigated as electrocatalysts towards oxygen evolution reaction (OER) in alkaline medium. 相似文献
104.
Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study
Objective
To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).Material and methods
Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).Results
There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.Conclusions
Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. 相似文献105.
106.
AIM: To investigate variations in the root canal systems of first and second permanent mandibular molar teeth in a Sudanese population using a clearing technique. METHODOLOGY: Two hundred extracted first and second permanent mandibular molars from three cities in the state of Khartoum were studied. Access cavities were prepared and pulp tissue was removed by immersion in 5% sodium hypochlorite under ultrasonication; Indian ink was then injected into the root canal systems assisted by a vacuum applied apically. The teeth were rendered clear by demineralization and immersion in methyl salicylate before evaluation. The following observations were made (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root and (iv) root canal configuration. RESULTS: Overall 59% of mandibular first molars had four canals with 3% having a third distolingual root. Seventy-eight per cent of second mandibular molars had two separate flat roots, whilst 10% were C-shaped. The most common canal system configurations were type IV (73%) and type II (14%). Inter-canal communications were more common in the mesial roots. The prevalence of inter-canal communications was 65% in first molars and 49% in second molars. CONCLUSIONS: In this sample of Sudanese teeth, 59% of the mandibular first permanent molars had four root canals whilst 10% of the mandibular second molars had C-shaped roots/canals. 相似文献
107.
Discoid lupus erythematosus is a manifestation of chronic cutaneous lupus erythematosus with a small risk of systemic involvement. In this review article, the role of predisposing factors such as haplotype, hormones, antibodies and sunlight are discussed. The clinical features, including variants and associations, and management options are presented. 相似文献
108.
Emergence of DHA-1-producing Klebsiella spp. in the Parisian region: genetic organization of the ampC and ampR genes originating from Morganella morganii 下载免费PDF全文
Verdet C Benzerara Y Gautier V Adam O Ould-Hocine Z Arlet G 《Antimicrobial agents and chemotherapy》2006,50(2):607-617
Eleven Klebsiella pneumoniae clinical isolates and one Klebsiella oxytoca clinical isolate showing various pulsed-field gel electrophoresis types and producing an inducible DHA-1 class C beta-lactamase were isolated in the Parisian region between 1998 and 2003. The aim of this study was to compare the genetic organization of the bla(DHA-1) genes in this collection of clinical isolates. In four isolates, the Morganella morganii-derived genomic region containing bla(DHA-1) was inserted in an entire complex sul1-type integron, including a region common to In6-In7 (CR1), as previously described in a bla(DHA-1)-producing Salmonella enterica serovar Enteritidis KF92 isolate from Saudi Arabia in 1992. Different gene cassette arrays were characterized in each of these integrons. In two of them, an additional 10-kb fragment was inserted between the CR1 and the M. morganii-derived region and was similar to the sap (ABC transporter family) and psp (phage shock protein) operons originated from Salmonella enterica serovar Typhimurium. The length of the M. morganii region was variable, suggesting that several independent recombination events have occurred and that open reading frame orf513 encodes a recombinase involved in the mobilization of the resistance genes. The genetic organization of bla(DHA-1) was identical in the eight other isolates. This structure is likely derived from a complex integron following the insertion of IS26, leading to the deletion of the first part of integron. The horizontal transfer of one plasmid carrying that truncated integron was shown for seven of these isolates. 相似文献
109.
The effect of ovarian steroids on epithelial ciliary beat frequency in the human Fallopian tube 总被引:3,自引:3,他引:3
Mahmood T; Saridogan E; Smutna S; Habib AM; Djahanbakhch O 《Human reproduction (Oxford, England)》1998,13(11):2991-2994
Using a method that detects variations in light intensity we have studied
the effect of ovarian steroids on human Fallopian tube epithelial ciliary
beat frequency in vitro. We have found that baseline ciliary beat frequency
averages between 5-6 Hz. Cilia from ampullary segments of the Fallopian
tube beat significantly faster (5.4 Hz+/-0.2) than those from fimbrial
segments (4.8 Hz+/-0.2). There was no significant difference in baseline
ciliary beat frequency at any other anatomical site in the Fallopian tube.
Incubation with progesterone (10 micromol/l) suppresses human Fallopian
tube epithelial ciliary beat frequency by 40-50%. This inhibition was
observed at similar magnitudes in all Fallopian tubes studied irrespective
of anatomical site. Progesterone-induced reductions in ciliary beat
frequency were concentration dependent and prevented by the progesterone
receptor antagonist mifepristone (RU486). Oestradiol alone (10 micromol/l)
had no effect on ciliary beat frequency at any anatomical site in the
Fallopian tube but did prevent the reduction in ciliary beat frequency seen
with progesterone when tissues were incubated with these two steroids
together.
相似文献
110.