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1.
BACKGROUND AND OBJECTIVE: An observational case series to assess the value of positron emission tomography (PET) in staging ocular adnexal lymphomas and evaluating their response to therapy. PATIENTS AND METHODS: The clinical records of 16 consecutive patients with ocular adnexal lymphoma for whom pretreatment and posttreatment PET scans and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) scans were available were compared. RESULTS: Pretreatment PET scans demonstrated fluorine 18-fluorodeoxyglucose (FDG) positive lesions in 15 orbits of 12 patients. In 1 patient with low-grade follicular lymphoma of the orbit, PET revealed an additional focus of lymphoma in the deltoid muscle that was missed on clinical examination and conventional radiography. All of the posttreatment PET scans showed complete resolution of FDG uptake, suggesting good response to therapy. However, posttreatment CT and MRI scans demonstrated residual masses in 3 patients. CONCLUSIONS: PET is valuable for initial staging of ocular adnexal lymphomas and may be a good adjunct to conventional imaging in evaluation of response to therapy.  相似文献   
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We hypothesized that the pathological effects on the neonatal rat heart could be aggravated by Cu deficiency due to the combined effects of caffeine exposure and malnutrition. Upon birth, pups were mixed and randomly picked; 8 pups were assigned to each dam and then divided into 4 groups. Group 1 dams received a normal diet containing 20% protein. Group 2 dams were fed 20% protein diet supplemented with caffeine (4 mg/100 g BW). Group 3 dams received 6% protein diet as a malnourished group, and group 4 dams received 6% protein diet supplemented with caffeine (4 mg/100 g BW). On postnatal day 10, dams and pups were killed. Group 2 tended to have a decrease in the Cu levels of dams' plasma and milk and in pups' plasma and heart tissue compared to those of group 1. This pattern was not observed consistently between groups 3 and 4. Transmission electron microscopy of group 2 pups' hearts revealed a degree of disruption in the mitochondria compared to normal mitochondria seen in group 1. There was no consistent change in the mitochondria of group 4 compared to group 3. The caffeine level observed in all categories of group 4 (dams' plasma and milk, pups' plasma and heart tissue) was lower than those in group 2. Although malnutrition affected body weight and heart weight, combined effects of caffeine and malnutrition on Cu content in the neonatal heart was relatively minor compared to the well nourished group. This well nourished group showed that the effects of caffeine on Cu were more consistent, resulting the changes of mitochondria.  相似文献   
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The lichen planus (LP) is an inflammatory and immune‐mediated disorder that can affect the hair, mucous membranes, nails, and skin. Lichen planus rarely affects the lips. In cases of lip involvement, it presents as radiated streaks, lace‐like papules, and erosions. There is no report of lip LP presenting as hypertrophic plaque. Here, we report interesting and rare clinical presentations of LP in a 45‐year‐old male patient that presented with a verrucous hyperkeratotic plaque on the lower lip mimicking squamous cell carcinoma. However, oral examination revealed, reticulated white patches on the bilateral buccal mucosa, and a biopsy of the lip lesion revealed lichenoid dermatitis which led to the diagnosis of hypertrophic lichen planus. Familiarity with the different clinical presentations of LP and its variants is essential for prompt diagnosis and effective treatment.  相似文献   
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BackgroundRhinovirus (RV) is the main cause of asthma exacerbations in children. Some studies reported that persons with asthma have attenuated interferon (IFN) responses to experimental RV infection compared with healthy individuals. However, responses to community-acquired RV infections in controls and children with asthma have not been compared.ObjectiveTo evaluate nasal cytokine responses after natural RV infections in people with asthma and healthy children.MethodsWe compared nasal cytokine expression among controls and children with asthma during healthy, virus-negative surveillance weeks and self-reported RV-positive sick weeks. A total of 14 controls and 21 patients with asthma were studied. Asthma disease severity was based on symptoms and medication use. Viral genome was detected by multiplex polymerase chain reaction. Nasal cytokine protein levels were determined by multiplex assays.ResultsTwo out of 47 surveillance weeks tested positive for RV, illustrating an asymptomatic infection rate of 5%. A total of 38 of 47 sick weeks (81%) tested positive for the respiratory virus. Of these, 33 (87%) were positive for RV. During well weeks, nasal interleukin 8 (IL-8), IL-12, and IL-1β levels were higher in children with asthma than controls. Compared with healthy virus-negative surveillance weeks, IL-8, IL-13, and interferon beta increased during colds only in patients with asthma. In both controls and children with asthma, the nasal levels of interferon gamma, interferon lambda-1, IL-1β, IL-8, and IL-10 increased during RV-positive sick weeks. During RV infection, IL-8, IL-1β, and tumor necrosis factor-α levels were strongly correlated.ConclusionIn both controls and patients with asthma, natural RV infection results in robust type II and III IFN responses.  相似文献   
6.
Statement of problemIntraoral scanners have been increasingly used in recent years. However, the accuracy of digital scans as it affects marginal adaptation is unclear.PurposeThe purpose of this systematic review and meta-analysis was to compare the marginal adaptation of single-unit zirconia crowns fabricated with digital scans or with conventional impressions.Material and methodsThe electronic databases PubMed (MEDLINE), Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science (ISI), Scopus, and EMBASE were searched and complemented by a manual search. Risks of bias were assessed by using a modified methodological index for nonrandomized studies (MINORS). Mean ±standard deviation (SD) values of marginal accuracy of studies were extracted for both methods. Mean marginal difference and 95% confidence interval (CI) were calculated to evaluate the marginal accuracy of each method. Pooled data were statistically analyzed by using a random-effect model.ResultsSeventeen studies were used to perform the meta-analysis. Subgroup analysis was performed based on intraoral scanners. Standardized mean marginal difference and 95% CI of each subgroup were as follows: Lava: -0.85 μm (95% CI: -1.67, -0.03) (P=.043); CEREC: -1.32 μm (95% CI: -2.06, -0.59) (P<.001); iTero: -0.44 μm (95% CI: -1.35, 0.47) (P=.338); TRIOS: -1.26 μm (95% CI: -2.02, -0.51) (P=.001); unknown scanner: -0.21 μm (95% CI: -1.14, 0.72); all studies: -0.89 μm (95% CI: -1.24, -0.54) (P<.001).ConclusionsDigital scanning of prepared teeth for single-unit zirconia restorations resulted in better marginal accuracy than conventional techniques using elastomeric impression materials.  相似文献   
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BackgroundHuman amniotic membranes (HAMs), as a biological membrane with healing, osteogenic, and cell therapy potential, has been in the spotlight to enhance the outcomes of treating bone defects. Present study aims to clinically assess the potential of HAM loaded with buccal fat pad-derived stem cells (BFSCs) as an osteogenic coverage for onlay bone grafts to maxillomandibular bone defects.Materials and methodsNine patients with jaw bone defects were enrolled in the present study. The patients were allocated to two study groups: Iliac crest bone graft with HAM coverage (n = 5), and Iliac bone grafts covered with HAM loaded with BFSCs (n = 4). Five months following the grafting and prior to implant placement, cone beam computed tomography was performed for radiomorphometric analysis.ResultsThe mean increase in bone width was found to be significantly greater in the HAM + BFSCs group (4.42 ± 1.03 mm versus 3.07 ± 0.73 mm, p < 0.05). Further, the changes in vertical dimension were greater in the HAM + BFSCs group (4.66 ± 1.06 mm versus 4.14 ± 1.03 mm, p > 0.05).ConclusionCombined use of HAM with mesenchymal stem cells may enhance bone regeneration specifically in the horizontal dimension. Moreover, this methodology reduces the amount of harvested autogenous bone and diminish secondary bone resorption.  相似文献   
9.
The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8) and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10) and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.  相似文献   
10.
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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