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51.
Computed tomography (CT) was used to study 25 patients with congenital conductive hearing loss and normal external auditory canals. Deformities were subdivided according to ossicular, fenestral, and cholesteatomatous origin. Isolated ossicular deformities were found in 14 patients (five bilateral), cholesteatoma in eight, oval-window nondevelopment (with ossicular deformity) in one, and normal studies in two (congenital stapes fixation at the level of the annular ligament). Ossicular deformities may be subdivided into incudostapedial disconnections into incudostapedial disconnections (most common), malleoincudal fixations, and stapes fixations. Most are due to developmental anomaly of the first or second branchial arch. The stapes has a dual origin (second arch and otic capsule). A cholesteatoma is defined as congenital only if there is no history of otitis and the tympanic membrane is intact. In this series, six were in the middle ear proper, and two were within the attic beyond otoscopic view. Their CT appearance, with one exception, was essentially identical to that of acquired lesions.  相似文献   
52.
ABSTRACT: The epidemiology of scabies for the last twelve years has been studied in Turkey. Information was obtained from three regions (Istanbul. Ankara and Erzurum) having different climates. There has been an increase in scabies in the years following 1969 in Ankara and Erzurum and from 1967 on in Istanbul. it reached Us maximum in 1978 in Erzurum. while this peak had been observed in early 1970s in other regions. Scabies incidence has significantly increased and de creased in winters and summers respectively, has been found to affect particularly the age group 15–44. and was observed more frequently in men than in women. Scabies seems to be moving to the eastern parts of Turkey.  相似文献   
53.
54.

Introduction  

Bisphosphonates are mostly used in the treatment of bone metastases. They have been shown to act synergistically with other chemotherapeutic agents. It is not known, however, whether similar synergistic effects exist with radiation on breast cancer cells.  相似文献   
55.
56.
Immunosuppression is a well-recognized cause of skin tumors, in particular squamous cell carcinomas (SCC). In patients with hematological malignancies undergoing chemotherapy, SCC has been reported late in the course of the disease or many years after completion of treatment. Here we report a patient with acute myeloid leukemia who developed a SCC of the tongue while receiving the third course of induction chemotherapy. This is the second such case in the medical literature. The role of immunosuppression, chemotherapy, the malignancy itself and possible genetic predisposition is discussed and the literature on this topic is reviewed.  相似文献   
57.
Background: Atrial fibrillation (AF) occurs due to various etiologies that carry different risks for thromboembolism. However, the effect of different etiologies on left atrial appendage (LAA) function has not been investigated. This study aimed to examine the LAA function in AF that occurred under various etiologies and to compare the findings with a novel tissue Doppler imaging (TDI) technique by using transesophageal echocardiography (TEE). Methods: LAA function was assessed in 84 patients with permanent AF according to various etiologies [mitral stenosis in 20 (24%), hypertension in 44 (52%), and hyperthyroidism in 20 (24%) patients] and in 23 controls with sinus rhythm. LAA area change, PW-Doppler and tissue velocities of LAA were measured. The presence of SEC or thrombus and their relation to LAA function was evaluated. Results: LAA velocities were lowest in mitral stenosis and highest in hyperthyroidism. Moderate–severe LAA SEC was detected in 61 and thrombi in 23 patients. Factors associated with the severity of SEC were the percentage of the LAA area change, PW-Doppler peak emptying velocity, and TDI septal wall downward velocity. The percent of the LAA area change and PW-Doppler peak emptying velocity were the significantly related factors for the presence of thrombi (OR = 0.84, 95% CI = 0.74–0.95, P = 0.005 and OR = 0.85, 95% CI = 0.74–0.98, P = 0.02, respectively). Conclusion: LAA function deteriorated most severely in mitral stenosis and least in hyperthyroidism. The LAA area change and PW-Doppler emptying velocity were important predictors for SEC or thrombi. Although TDI was not superior to classical methods, it provided complementary data to PW-Doppler velocities for predicting SEC and thrombi.  相似文献   
58.
Acrylic resin dentures may have cytotoxic effects on oral soft tissues. However, there is sparse data about the cytotoxic effect of fibre-reinforced acrylic resin denture base materials. The purpose of this in vitro study was to determine the effect of two fibre impregnation methods on the cytotoxicity of a glass and carbon fibre-reinforced heat-polymerized acrylic resin denture base material on oral epithelial cells and fibroblasts. One hundred acrylic resin discs were assigned to five experimental groups (n = 20). One of the groups did not include any fibre. Two groups consisted of silane and monomer treated glass fibres (Vetrolex) impregnated into acrylic resin (QC-20) discs. The other two groups consisted of silane and monomer treated carbon fibres (Type Tenox J, HTA). Untreated cell culture was used as positive control. The human oral epithelial cell line and buccal fibroblast cultures were exposed to test specimens. The cytotoxicity of the test materials was determined by succinic dehydrogenase activity (MTT method) after 24 and 72 h exposures. Data were analysed with a statistical software program (SPSSFW, 9.0). A one-way analysis of variance (anova) test and Bonferroni test were used for the comparisons between the groups. All statistical tests were performed at the 0.95 confidence level (P < 0.05). After 24 and 72 h incubation, cell viability percentages of all experimental groups showed significant decrease according to the positive control cell culture. Fibroblastic cell viability percentages of silane and monomer treated fibre-reinforced groups were lower than the unreinforced group. Cell viability of monomer-treated groups displayed the lowest percentages. Elapsed incubation time decreased epithelial cell viability in silane-treated groups. Fibroblastic cell viability was not influenced by elapsed time except the unreinforced group.  相似文献   
59.
Brucellosis is an important cause of spondylodiscitis in endemic areas. Brucellar spondylodiscitis is a serious complication because of its association with abscess formation. Prospective studies comparing patients with and without abscesses are lacking. The objective of this study was to determine the frequency and demographic, clinical, laboratory, and radiological features of brucellar spondylodiscitis and to compare patients with and without abscesses regarding treatment and outcome. Out of 135 consecutive patients with brucellosis, 31 patients with spondylodiscitis were recruited for the study. Patients were grouped according to magnetic resonance imaging findings. The frequency of spondylodiscitis was 23.0 %. Sites of involvement were lumbar (58.1 %), lumbosacral (22.6 %), cervical (9.7 %), thoracolumbar (6.5 %), and thoracic (3.2 %). Abscesses occurred in 19 (61.3 %) patients and were associated with low hemoglobin levels. Medical treatment included a combination of streptomycin (for the first 3 weeks), doxycycline, and rifampin. The total duration of treatment was 12–39 (mean 17.0 ± 8.5 SD) weeks. By 12 weeks of treatment, evidence of clinical improvement (67 vs. 28 %) and radiological regression (92 vs. 50 %) was significantly greater in patients without abscesses. The duration of treatment was longer if an abscess was present. Two female patients with abscesses required surgical intervention. Both patients presented with high fever, neurologic deficit, and high Brucella standard tube agglutination test titers. Each patient should be evaluated individually, based on clinical findings, laboratory data, and radiological results, when undergoing treatment for brucellar spondylodiscitis. If abscesses are found, a longer course of treatment and even surgical intervention may be needed.  相似文献   
60.

Background:

Heart failure patients frequently have thyroid function abnormalities. Cardiac resynchronization therapy (CRT) is a major treatment for patients with advanced chronic heart failure. We aimed to investigate the effects of CRT on thyroid functions.

Hypothesis:

CRT improves thyroid functions.

Methods:

Fifty‐seven patients (42 male, 15 female; mean age 58 ± 13 y) undergoing CRT were included in the study. Serum levels of thyroid hormones and echocardiographic parameters were measured before and 6 months after CRT. A response to CRT was defined as a reverse remodeling detected by a relative increase of ≥15% in left ventricular ejection fraction.

Results:

The clinical status and functional capacity of the patients in the remodeling group were improved significantly. The mean New York Heart Association class was reduced from 3.2 ± 0.4 to 2.2 ± 0.4 (P<0.001). The free triiodothyronine (fT3) level increased from 2.67 pg/mL to 2.97 pg/mL in the reverse remodeling group (P = 0.005). The fT3/fT4 ratio increased from 1.81 to 2.34 (P = 0.006).

Conclusions:

CRT improves fT3 levels and fT3/fT4 ratio, which may play an important role in reverse remodeling. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.  相似文献   
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