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81.
BACKGROUND: The primary goal of ultrasonography (US) in the evaluation of a thyroid nodule is to determine its malignancy, although the diagnosis of a malignant nodule on the basis of US alone is nearly impossible. The aim of this prospective study was to evaluate the predictive value of sonographic features in the preoperative diagnosis of malignant thyroid nodules, and to determine the important features of sonography. METHODS: This prospective study included 550 consecutive patients with , thyroid nodules. Nodules were divided into two groups on the basis of pathological diagnosis: group 1 consisted of 1,633 nodules with a benign pathology, and group 2 consisted of 293 nodules with a malignant pathology. RESULTS: Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were more common in malignant nodules compared to benign nodules (89.1% versus 5%; 64.5% versus 4.7%; 81.6% versus 30.6% ; and 62.5% versus 43.1%, respectively; p < 0.001). There was a positive correlation between the detection of malignant thyroid nodules and microcalcification (rs = 0.791, p = 0.0001), blurred nodular margin (rs = 0.625, p = 0.0001), solid appearance (rs = 0.376, p = 0.0001), and hypoechoic appearance (rs = 0.141, p = 0.0001). Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were independent determinants of malignancy upon US examination of thyroid nodules (OR: 159, OR: 37, OR: 9.9, and OR: 2.2, respectively). CONCLUSION: Although we did not identify a single feature indicative of malignancy in the sonographic examination of nodules, microcalcification and blurred margin were the strongest correlates for malignancy.  相似文献   
82.
Spontaneous rupture of the Achilles tendons in hemodialysis patients is a rare complication. The majority of these patients have additional predisposing factors, such as previous use of fluoroquinolone antibiotics or corticosteroids. Spontaneous rupture of bilateral Achilles tendons without any of those predisposing factors is exceptional. In this paper, we report a 43-year-old woman who had been undergoing regular hemodialysis for 16 years. She developed bilateral spontaneous and simultaneous rupture of the Achilles tendons. She also developed pathological fracture of right femur neck 3 years later. Based on previous cases of tendon ruptures in uremic patients and the lack of history for the use of corticosteroids or fluoroquinolones, we believe that secondary hyperparathyroidism is the predisposing factor in this patient.  相似文献   
83.
Numerous treatment modalities have been tried with diverse results for pruritus due to notalgia paresthetica (NP). Corticosteroids suppress ectopic neural discharges from injured nerve fibers and also have short‐lived suppressive effect on transmission in normal C‐fibers. Herein, we evaluated the efficacy of intralesional triamcinolone acetonide in the treatment of NP. The medical reports of five patients who had been diagnosed with NP and treated with intralesional triamcinolone acetonide injections were retrospectively evaluated. Triamcinolone acetonide solution was injected intradermally (10 mg/mL; 0.1 mL/cm2) every 3 weeks for a maximum of four treatments. The severity of itch was scored by the patients on a combined numerical and visual analogue scale. After treatment, reduction in itch severity scores varied between 33% and 100%.  相似文献   
84.
Summary Split or full thickness eyelid defects resulting from tumor destruction or surgical excision present a dilemma for plastic and reconstructive surgeons. Full thickness eyelid replacement requires composite grafting of the skin, together with tarsal support of its substitute and mucosa. The flap described by Fricke in 1829 was used for reconstruction of anterior lamella in six lower eyelid defects. In three of our cases chondromucosal grafts taken from nasal septum were utilized for posterior lamella repair. The results have been satisfactory from a functional and cosmetic standpoint.  相似文献   
85.
Kounis syndrome is a life-threatening medical condition that causes severe allergic reaction and acute coronary syndrome. Benzathine penicillin G is one of the most widely used antibiotics in clinical practice, but it can enhance both allergic and hypersensitivity complications. In this report, we describe the case of a 42-year-old man admitted to our hospital who presented with cryptic tonsillitis accompanied by angioneurotic edema, chest pain, and electrocardiographic variations. The patient was diagnosed with Kounis syndrome and treated with oral antihistamines and prednisolone. He was discharged following a complete recovery and regression of electrocardiographic abnormalities within 72 hours.  相似文献   
86.
Experimental external irradiation of corneal neovascularization   总被引:1,自引:0,他引:1  
The clinical effect of ionidizing radiation on ocular neovascularizations is controversial not only because of the variety of treatment modalities. The aim of our study was to investigate an experimental model which allows to evaluate radiation parameters and to study the mechanism of the inhibitory effect on neoangiogenesis. METHODS: Corneal angiogenesis was induced by use of a micropocket assay in NZW rabbits. Pellets with 500 ng bFGF in 2% methylecellulose were implanted into the stroma 2.0 mm from the limbus. Initiation of vessel growth occurred on day 3. At this time radiation was performed with different doses (single dose of 15 to 30 Gy or fractionated 5 x 5 Gy) using a 6 MeV linear accelerator. Vascular growth was quantified. RESULTS: Irradiation with a total dose of 25 Gy applied in a fractionated regimen or as single-dose irradiation on the day of surgery or on day 6 after surgery did not significantly reduce neovascular growth. In contrast, postoperative radiation therapy on day 3 was able to reduce the area of ingrowing vessels significantly (P < 0.01). In spite of the relatively high dose there were no significant side effects during the observation period of 8 weeks. CONCLUSION: Our results show that single-dose radiation (> or = 25 Gy) is sufficient to inhibit the growth of corneal neovascularizations. With this model it might be possible to investigate parameters for therapy of ocular neovascularizations as well as the underlying mechanisms.  相似文献   
87.
The aim of this study was to investigate the effects of the application of gaseous ozone and Nd:YAG laser on glass‐fibre post bond strength. Forty‐two madibular premolar roots were cut, endodontically instrumented and irrigated with 2.5% NaOCl. Post spaces were prepared and roots were divided into three groups (n = 14). The antimicrobial pretreatment was conducted as follows: gaseous ozone, Nd:YAG laser and control (no additional disinfection methods). Scanning electron microscope analysis was made for each group (n = 2). A resin cement was used for luting the posts. For push‐out test, each root was cut horizontally (two cervical, two middle and two apical). Statistical analyses were performed with one‐way anova (α = 0.05). Fracture types were observed. There was no statistically significant difference between the groups (P > 0.05). There were statistically significant differences in cervical and apical segments of laser and control groups (P < 0.05). The disinfection of the post spaces with Nd:YAG laser and ozone had no adverse effects on bond strength of glass‐fibre post.  相似文献   
88.
89.
The seroprevalence of Helicobacter pylori and nitric oxide in acne rosacea   总被引:5,自引:0,他引:5  
BACKGROUND: Acne rosacea is a dermatosis with unknown etiology. Some studies have reported a high prevalence of Helicobacter pylori infection in acne rosacea. Other studies have reported a decrease in the severity of the lesions of acne rosacea after eradication of H. pylori. H. pylori is a Gram-negative bacterium which colonizes the gastric mucosa and increases the synthesis of oxygen radicals, such as superoxide and proinflammatory cytokines. These cytokines have been demonstrated to stimulate the synthesis of the inflammatory species nitric oxide (NO). In this study, we examined the role of NO in the possible effect of H. pylori in acne rosacea. METHODS: Thirty-three acne rosacea patients were included in the study and the control group comprised 20 healthy individuals. The levels of immunoglobulin G antibodies against H. pylori in the serum samples were measured using the enzyme-linked immunoabsorbent assay method. Measurement of nitrate was performed using chemiluminescence in accordance with the method described by Braman and Hendrix (Braman RS, Hendrix SA. Nanogram nitrite and nitrate determination in environmental and biological materials by vanadium(iii) reduction with chemiluminescence detection. Anal Chem 1989; 61: 2715-2718). For statistical analysis, the t-test was used. RESULTS: The seropositivity of H. pylori in acne rosacea patients was found to be high; however, the serum nitrate levels were found to be normal. CONCLUSIONS: The results of the study indicate that the inflammatory species NO, which has been hypothesized to be associated with H. pylori, has no role in the inflammatory mechanism of acne rosacea.  相似文献   
90.

目的:使用缺氧模型探究乙酰左旋肉碱(ALCAR)对人视网膜色素上皮(ARPE-19)细胞活力、形态完整性和血管内皮生长因子(VEGF)表达的影响。

方法:第一组实验通过暴露ARPE-19细胞培养物于不同浓度确定最佳CoCl2剂量。建立五组ARPE-19细胞培养物,包括对照组,假手术组(200 μM CoCl2)和分别接受1、10、100 mM ALCAR联合200 μM CoCl2组,以评估ALCAR对细胞活力的影响。使用MTT法测量细胞活力。通过倒置相差显微镜观察细胞的形态特征。采用酶联免疫吸附实验(ELISA)检测ARPE-19细胞分泌VEGF和HIF-1α的水平。

结果:ARPE-19细胞暴露于不同剂量的CoCl2中,以创建缺氧模型。然而,暴露于浓度为200 μM CoCl2时,细胞活力显著降低至83%。ALCAR在1 mM和10 mM浓度下可增加细胞活力,而最大浓度(100 mM)没有额外效果。与假手术组相比,浓度为1 mM和10 mM ALCAR组的细胞活力显著更高(P=0.041、0.019)。细胞活力和形态不受最大剂量ALCAR(100 mM)的影响。与假手术组相比,10 mM ALCAR组VEGF和HIF-1α水平显著降低(P=0.013、0.033)。

结论:ALCAR是可行的治疗选择,可为视网膜疾病开辟新的治疗途径,与年龄相关性黄斑变性(AMD)特别相关。然而,仍需开展进一步研究明确定义其确切机制,以期充分阐明ALCAR对抗视网膜疾病的应用潜力。  相似文献   

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