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111.
Low-level laser therapy (LLLT) has been used to accelerate wound healing, yet questions remain concerning its therapeutic applications. This study aimed to compare the healing efficacy of helium-neon (He-Ne) red light (laser) and gallium aluminum arsenide (Ga-Al-As) infrared lasers at two different doses on hard palate wounds. In a randomized controlled study, 75 adult male mice were divided into five groups of 15 each, after undergoing identical surgical procedures; a control group, with no laser irradiation; HD1 and HD2 groups, treated with He-Ne laser (wavelengths 632.8 nm, power 5 mW, and spot size 0.02 cm2) at doses of 4 J/cm2 and 7.5 J/cm2 respectively; and GD1 and GD2 groups, treated with Ga-Al-As laser (wavelengths 830 nm, peak power 25 mW, and spot size 0.10 cm2) at the doses of 4 J/cm2 and 7.5 J/cm2, respectively. Five animals from each group were killed on the third, seventh, and 14 days after surgery, and biopsies were made for histological analysis. On the 3rd and 7th day after the surgery, the number of polymorphonuclear cells (PMN) in HD1, HD2, GD1, and GD2 groups was significantly lower than that of the control group. On the 7th and 14th day, the fibroblasts and new blood vessels counts and collagen density fibers in HD1, HD2, GD1, and GD2 groups were also significantly higher than that of the control groups, and the fibroblast counts and collagen density fibers in HD1 and HD2 groups were higher than that of the GD1 and GD2 groups. LLLT with He-Ne laser compared to Ga-Al-As laser has a positive healing effect on hard palate gingival wounds in mice regardless of the radiation dose.  相似文献   
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We sought to characterise adolescent wheeze in the absence of asthma, which we termed "undiagnosed wheeze". The Isle of Wight Birth Cohort (n=1,456) was reviewed at 1, 2, 4, 10 and 18 yrs. Using questionnaire responses, "asthma" was defined as "ever had asthma" plus either "wheezing in the last 12 months" or "taking asthma treatment in the last 12 months"; "undiagnosed wheeze" as "wheeze in the last 12 months" but "no" to "ever had asthma"; and remaining subjects termed "non-wheezers". Undiagnosed wheeze (prevalence 4.9%) accounted for 22% of wheezing at 18 yrs. This was largely adolescent-onset with similar symptom frequency and severity to diagnosed asthma. However, undiagnosed wheezers had significantly higher forced expiratory volume in 1 s to forced vital capacity ratio, less bronchodilator reversibility and bronchial hyperresponsiveness, and were less frequently atopic than asthmatics. Undiagnosed wheezers had earlier smoking onset, higher smoking rates and monthly paracetamol use than non-wheezers. Logistic regression identified paracetamol use (OR 1.11, 95% CI 1.01-1.23; p=0.03), smoking at 18 yrs (OR 2.54, 95% CI 1.19-5.41; p=0.02), rhinitis at 18 yrs (OR 2.82, 95% CI 1.38-5.73; p=0.004) and asthmatic family history (OR 2.26, 95% CI 1.10-4.63; p=0.03) as significant independent risk factors for undiagnosed wheeze. Undiagnosed wheeze is relatively common during adolescence, differs from diagnosed asthma and has strong associations with smoking and paracetamol use. Better recognition of undiagnosed wheeze and assessment of potential relevance to adult health is warranted.  相似文献   
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Nowadays, chemotherapy is one of the crucial and common therapies in the world. So far, it has been revealed to be highly promising, yet patients suffer from the consequences of severe negative medical dosages. In order to overcome these issues, the enhancement of photothermal chemotherapy with reduced graphene oxide (rGO) as a photothermal agent (PTA) is widely utilised in current medical technologies. This is due to its high near-infrared region (NIR) response, in vitro or in vivo organism biocompatibility, low risk of side effects, and effective positive results. Moreover, rGO not only has the ability to ensure that selective cancer cells have a higher mortality rate but can also improve the growth rate of recovering tissues that are untouched by necrosis and apoptosis. These two pathways are specific diverse modalities of cell death that are distinguished by cell membrane disruption and deoxyribonucleic acid (DNA) disintegration of the membrane via phosphatidylserine exposure in the absence of cell membrane damage. Therefore, this review aimed to demonstrate the recent achievements in the modification of rGO nanoparticles as a PTA as well as present a new approach for performing photochemotherapy in the clinical setting.

rGO of QD-rGO nanocomposite could absorb and convert into heat when harvested under NIR radiation, resulting cell death with reduction of fluorescence.  相似文献   
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Polysulfone (PSF) was prepared under high shear in a vortex fluidic device (VFD) operating in confined mode, and its properties compared with that prepared using batch processing. This involved reacting the pre-prepared disodium salt of bisphenol A (BPA) with a 4,4′-dihalodiphenylsulfone under anhydrous conditions. Scanning electron microscopy (SEM) established that in the thin film microfluidic platform, the PSF particles are sheet-like, for short reaction times, and fibrous for long reaction times, in contrast to spherical like particles for the polymer prepared using the conventional batch synthesis. The operating parameters of the VFD (rotational speed of the glass tube, its tilt angle and temperature) were systematically varied for establishing their effect on the molecular weight (Mw), glass transition temperature (Tg) and decomposition temperature, featuring gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) respectively. The optimal VFD prepared PSF was obtained at 6000 rpm rotational speed, 45° tilt angle and 160 °C, for 1 h of processing with Mw ∼10 000 g mol−1, Tg ∼158 °C and decomposition temperature ∼530 °C, which is comparable to the conventionally prepared PSF.

Polysulfone (PSF) was prepared under high shear in a vortex fluidic device (VFD) operating in confined mode. This involved reacting the pre-prepared disodium salt of bisphenol A (BPA) with a 4,4′-dihalodiphenylsulfone under anhydrous conditions.  相似文献   
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Nosocomial infections are one of the major health problems that increase mortality. Pseudomonas aeruginosa is one of the important causes of nosocomial infections. This bacterium has a gene called the lasB gene, the product of which is a zinc-dependent metalloprotease. This gene plays a central role in the pathogenesis of Pseudomonas spp. This pathogen is highly toxic and destroys tissues and also has a moderating effect on the immune system; on the other hand, it initiates the intracellular pathway of biofilm growth. Although there are methods such as molecular methods for identifying the lasB gene, due to the high cost and the need for specialized personnel, it is necessary to replace them with an appropriate method. In this study, a gold nanoparticle-based DNA diagnostic sensor sensitive to the aggregation states of gold nanoparticles was used to identify amplified and non-amplified lasB genes. The results of the experiment were evaluated both visually and spectrally. The minimum detection value of this method was 10 ng of the amplified lasB gene and 50 ng of the non-amplified lasB gene. This method is very fast, simple, easy and low cost.

In this study, a gold nanoparticle-based DNA diagnostic sensor that is sensitive to the aggregation states of gold nanoparticles was used to identify the amplified and non-amplified lasB gene.  相似文献   
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Local effect of acetyl salicylic acid (ASA) on peripheral nerve regeneration was studied using a rat sciatic nerve transection model. Forty-five male healthy White Wistar rats were divided into three experimental groups (n = 15), randomly: Sham-operation (SHAM), control (SIL), and ASA-treated (SIL/ASA) groups. In SHAM group after anesthesia left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis the muscle was sutured. In SIL group the left sciatic nerve was exposed the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone tube and filled with 10 μl phosphate buffered solution. In SIL/ASA group defect was bridged using a silicone tube filled with 10 μl acetyl salisylic acid (0.1 mg/ml). Each group was subdivided into three subgroups of five animals each and were studied 4, 8, and 12 weeks after surgery. Data were analyzed statistically by factorial analysis of variance (ANOVA) and the Bonferroni test for pair-wise comparisons. Functional study confirmed faster and better recovery of regenerated axons in SIL/ASA than in SIL group (p < 0.05). Gastrocnemius muscle mass in SIL/ASA was significantly more than in SIL group. Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in SIL/ASA were significantly higher than in control group. In immuohistochemistry, location of reactions to S-100 in SIL/ASA was clearly more positive than in SIL group. Response to local treatment of ASA demonstrates that it influences and improves functional recovery of peripheral nerve regeneration.  相似文献   
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