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171.
Pneumolabyrinth can result from traumatic luxation of stapes into the vestibule. The diagnosis of stapes luxation following a head injury can be delayed especially if the otoscopic examination is within normal limits. Here a 15-year-old girl presenting with vertigo and nystagmus following a blunt head injury was presented, whose computerized tomography revealed air in the vestibule and cochlea (pneumolabyrinth) and stapes was found to be luxated into the vestibule.  相似文献   
172.
Echinococcosis is a frequently encountered parasitic disease in the Mediterranean region, including Turkey. Cardiac disease is seen in 0.5-2% of patients. Usually the cysts are located within the pericardium or intramyocardially; intracavitary localization of the cyst is rarely seen. We herein report a patient who initially presented with hemoptysis and was echocardiographically diagnosed to have an intra-atrial hydatid cyst. Although patients with cardiac hydatid cysts may present with cardiac symptoms, symptoms typically involve other organ systems, following dissemination of the organism. Therefore, echocardiographic screening of patients who are diagnosed with echinococcosis, even if they have no cardiac symptoms, may ensure early diagnosis and prevent development of lethal complications, such as cyst rupture or embolization.  相似文献   
173.
Previous research about coexistence of Helicobacter pylori (HP) and hepatitis A virus (HAV) infections and the factors that increase their prevalence has suggested that the route of transmission of HP infection includes oral-oral and water-foods as well as the fecal-oral route. The aim of this study was to evaluate the routes of transmission of HP by comparing the seroprevalences of HP and HAV in children. One hundred and two children aged 1-18 years living in rural and urban regions of Izmir were included in this study. Anti-HP IgG and anti-HAV IgG antibodies were measured via enzyme immunoassay method. Seropositivities for HP and HAV were 56.8% and 51.9%, respectively. Seroprevalence for both infections increased with increasing age. However, a significant difference could not be detected between rural and urban areas. Sex did not have a significant effect. There was no infection in 22.1% of children, while 30.8% had both of the infections. 21.1% were positive only for HAV while 26% were positive only for HP. No significant correlation between seroprevalences of HP and HAV was detected. This study suggests the existence of various other routes of transmission of HP apart from the fecal-oral route.  相似文献   
174.
PURPOSE: The purpose of this study was to evaluate the visual outcome and associated findings in isoametropic amblyopia due to high hyperopia. METHODS: Children with > or = 5 D spherical equivalent hyperopia and < or = 1.5 D anisometropia and < or = 1.5 D cylinder in both eyes were selected. Data were collected on the magnitude of spherical equivalent hyperopia, corrected visual acuity (VA) with the Snellen or Tumbling E charts, age at correction, duration of correction, ocular motility and strabismus. Children who had VA of < or = 0.4 in both eyes were defined as having isoametropic amblyopia. Associations between isoametropic amblyopia and factors affecting VA were analysed. RESULTS: A total of 160 children met the criteria. The mean follow-up was 55.8 months. In all, 31 of the children had isoametropic amblyopia. The mean age at presentation was significantly higher (5.5 years versus 4.1 years; p < 0.05) and strabismus was significantly less prevalent (p = 0.001) in the isoametropic amblyopes than in the high hyperopia group as a whole. A total of 83.9% of the isoametropic amblyopes had best corrected VA > 0.5 at the last visit. The duration of optical correction was positively correlated with the last recorded VA measurement. CONCLUSION: Isoametropic amblyopia is not rare among highly hyperopic children. Visual acuity improves satisfactorily with spectacle correction. The duration of optical correction seems to be an important factor in visual prognosis.  相似文献   
175.

Background

There is a need for a peripheral nerve model on which surgeons-in-training can simulate the repair of nerve injuries at their own pace. Although practicing on animal models/cadavers is considered the “gold standard” of microsurgical training, the proposed model aims to provide a platform for improving the technical skills of surgical trainees prior to their practice on cadaver/animal models. In addition, this model has the potential to serve as a standardized test medium for assessing the skill sets of surgeons.

Methods

Several formulations of silicone were utilized for the design and fabrication of a model which realizes the hierarchical structure of peripheral nerves. The mechanical properties were characterized via the Universal Testing Machine; the damage caused by the needle on the entry sites was assessed through scanning electron microscopy (SEM).

Results

Mechanical properties of the formulations of silicone were tested to mimic human peripheral nerves. A formulation with 83.3?wt% silicone oil and 0.1?wt% cotton fiber was chosen to be used as nerve fascicles. Both 83.3?wt% silicone oil with cotton fiber and 66.6?wt% silicone oil without fiber provided a microsuturing response similar to that of epineurium at a wall thickness of 1?mm. SEM also confirmed that the entry of the needle did not introduce significant holes at the microsuturing sites.

Conclusions

The proposed peripheral nerve model mimicked human tissues mechanically and cosmetically, and a simulation of the repair of a fifth-degree nerve injury was achieved.  相似文献   
176.
Riga‐Fede disease is an uncommon, benign, ulcerative condition due to dental trauma that can occur at any age. A 9‐year‐old boy with a painful tongue is presented. Physicians need to recognize Riga‐Fede disease and Riga‐Fede‐like disease to intervene early.  相似文献   
177.
178.
Hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer is defined by the presence of the estrogen receptor and/or the progesterone receptor and the absence of HER2 gene amplification. HR-positive/HER2-negative breast cancer accounts for 65%–70% of all breast cancers, and incidence increases with increasing age. Treatment varies by stage, and endocrine therapy is the mainstay of treatment in both early stage and late-stage disease. Combinations with cyclin-dependent kinase 4/6 inhibitors have reduced distant recurrence in the early stage setting and improved overall survival in the metastatic setting. Chemotherapy is used based on stage and tumor biology in the early stage setting and after endocrine resistance for advanced disease. New therapies, including novel endocrine agents and antibody-drug conjugates, are now changing the treatment landscape. With the availability of new treatment options, it is important to define the optimal sequence of treatment to maximize clinical benefit while minimizing toxicity. In this review, the authors first discuss the pathologic and molecular features of HR-positive/HER2-negative breast cancer and mechanisms of endocrine resistance. Then, they discuss current and emerging therapies for both early stage and metastatic HR-positive/HER2-negative breast cancer, including treatment algorithms based on current data.  相似文献   
179.
Inhibition of osteoclast (OC) activity has been associated with decreased tumor growth in bone in animal models. Increased recognition of factors that promote osteoclastic bone resorption in cancer patients led us to investigate whether increased OC activation could enhance tumor growth in bone. Granulocyte colony-stimulating factor (G-CSF) is used to treat chemotherapy-induced neutropenia, but is also associated with increased markers of OC activity and decreased bone mineral density (BMD). We used G-CSF as a tool to investigate the impact of increased OC activity on tumor growth in 2 murine osteolytic tumor models. An 8-day course of G-CSF alone (without chemotherapy) significantly decreased BMD and increased OC perimeter along bone in mice. Mice administered G-CSF alone demonstrated significantly increased tumor growth in bone as quantitated by in vivo bioluminescence imaging and histologic bone marrow tumor analysis. Short-term administration of AMD3100, a CXCR4 inhibitor that mobilizes neutrophils with little effect on bone resorption, did not lead to increased tumor burden. However, OC-defective osteoprotegerin transgenic (OPG(Tg)) mice and bisphosphonate-treated mice were resistant to the effects of G-CSF administration upon bone tumor growth. These data demonstrate a G-CSF-induced stimulation of tumor growth in bone that is OC dependent.  相似文献   
180.
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