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21.

PURPOSE

In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations.

MATERIALS AND METHODS

Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson''s correlation analysis was also performed to assess relationships between variables.

RESULTS

According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface.

CONCLUSION

Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings.  相似文献   
22.
23.

Background

Gouty arthritis (GA) is a chronic inflammatory arthritis in which both clinical and subclinical atherosclerosis are more frequent. The dynamic equilibrium between coagulation and fibrinolysis is impaired in inflammatory diseases. We determined TFPI and TAFI antigen levels in GA patients and evaluated their association with subclinical atherosclerosis.

Methods

We included 45 GA patients (41 males, 4 females; mean age: 51.6 years) and 25 asymptomatic hyperuricemic (AHU) subjects (19 males, 6 females; mean age: 48.1 years). Cardiovascular risk factors were determined. TAFI and TFPI levels were determined by ELISA. B-mode ultrasonography was used to detect subclinical atherosclerosis.

Results

Cardiovascular risk factors were similar in both groups. The carotid IMT was significantly higher in GA group than in AHU group (0.74 ± 0.23 mm vs. 0.61 ± 0.13 mm, p = 0.009). TFPI level was significantly higher in GA group than in AHU group (86.2 ± 48.9 ng/mL vs. 25.8 ± 21.4 ng/mL, p < 0.001); TAFI antigen was significantly higher in AHU group (22.6 ± 3.6 ng/mL vs. 25.7 ± 5.3 ng/mL, p = 0.006) than in GA patients. Atherosclerotic plaque formation was more frequent in GA group (p = 0.041). When GA patients with and without plaques were compared, the first group had significantly higher mean age (p = 0.01) and TFPI level (p = 0.028). TFPI level correlated with carotid IMT (r = 0.302; p = 0.028). Logistic regression analysis showed that age (OR: 1.236, 95%CI: 1.059-1.443, p = 0.007) and TFPI (OR: 1.031, 95%CI: 1.008-1.054, p = 0.008) were independent risk factors for the presence of plaques.

Conclusions

GA patients had more frequent subclinical atherosclerosis than subjects with AHU. Higher TFPI levels in GA patients –probably associated with enhanced endothelial damage- were related to subclinical atherosclerosis. Lower TAFI levels in GA pointed to impaired fibrinolysis.  相似文献   
24.
Sleep disturbances and problems are increased in ankylosing spondylitis (AS). But much is not known in a quantitative way about sleep problems and effect of treatments on AS. This study is aimed first, to investigate sleep disturbances in AS and secondly, to evaluate the effects of anti-TNF treatment on SD in AS. One hundred seventy-one (Female/male: 90/81) AS patients fulfilling modified New York criteria and 86 (F/M: 56/30) age- and gender-matched controls without inflammatory diseases were included into the study. Demographic data and disease activity and treatments were recorded using The Bath Ankylosing Spondylitis Functional Index (BASFI) and The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). The Medical Outcomes Study (MOS) Sleep Questionnaire was used for evaluating sleep and problems of sleep. AS patients had higher sleep disturbance scale (SDS) and sleep problem index (SPI) II scores. Group A (patients using NSAID and/or DMARD, 53.2% of patients) had higher BASDAI and BASFI compared with Group B (Patients using anti-TNF treatments) (4.29?±?2.38 vs. 2.46?±?2.32, p?<?0.001; 1.95?±?2.15 vs. 0.93?±?1.31, p?<?0.001, respectively). Whereas Group A had higher scores of SDS, awaken short of breath or headache, somnolence, and SPI-II than controls, none of the sleep parameters were statistically different between patients on anti-TNF treatments and controls. BASDAI was positively correlated with SPI-I, SPI-II, SDS, and somnolence scale. AS patients had increased sleep problems and disturbances compared with controls. Anti-TNF agents improve significantly these problems. Sleep problems are significantly correlated with the disease activity.  相似文献   
25.
Carpal tunnel syndrome (CTS) is one of the most frequent extra-articular manifestations of rheumatoid arthritis (RA). High frequency ultrasonography (US) is a sensitive and specific method in diagnosis of CTS. This study is aimed to: firstly assess diameter frequency of CTS in RA with US and compare with a control group; secondly, investigate relationship of CTS with disease activity. One hundred consecutive RA patients (women/men: 78/22) fulfilling ACR 1987 RA criteria and 45 healthy controls (women/control: 34/11) were enrolled into study. Disease activity parameters, RA and CTS patient global assessment and health assessment questionnaire (HAQ-DI) were recorded. Both patient and control group were questioned about secondary causes of CTS, and Katz hand diagram, Boston CTS questionnaire and Phalen ve Tinel tests were applied once for each hand. Wrist joint and carpal tunnel were assessed with US grey scale and power Doppler US, then cross-sectional area of median nerve (CSA) was calculated. Patients with median nerve CSA between 10.0 and 13.0 mm(2) were evaluated with electromyography (EMG). CTS was diagnosed if CSA of median nerve >13.0 mm(2) or CTS was shown with NCS. Although there was no difference between RA patients and controls in age, sex, history of DM (+) and goitre, CTS was more frequent in RA group (respectively, 17.0% vs. 4.4%, P = 0.038). In RA group with CTS, age, history of DM, disease duration, HAQ-DI score, CTS patient global score, Boston symptom severity and functional status scores were elevated compared to without CTS [respectively, 57 (36-73) vs. 50 (24-76), P = 0.041; 35.3% vs. 6.0%, P < 0.001; 108 (12-396) months vs. 72 (6-360) months, P = 0.036; 1.93 (0.75-2.87) vs. 1.125 (0-2.75), P = 0.013; 52 (1-97) vs. 25 (0-91), P = 0.001; 2.81 (1.18-4.17) vs. 2.0 (1.0-4.01), P = 0.01; 3.37 (1.37-5.0) vs. 2.25 (1.0-5.0), P = 0.008]. No difference was found between CTS (+) and (-) RA patients in acute phase reactants, disease activity and US findings (P > 0.05). Sensitivity of Katz hand diagram was higher than Tinel and Phalen tests (respectively, 100, 60.0, 66.7%). Boston symptom and functional scores of RA patients with CTS diagnosed by EMG were increased than patients CTS (-) by EMG [respectively, 3.05 (1.90-4.27) vs. 1.55 (1.0-2.90), P = 0.002; 3.25 (1.73-3.82) vs. 1.12 (1.0-2.10), P = 0.008]. CTS frequency in RA was found higher than normal population, especially in patients with additional risk factors of CTS. There was no relationship between CTS and disease activity. CTS group had long disease duration and worse functional status. CTS could be a result of the chronic course in RA. In patient with CSA between 10 and 13 mm(2), Boston CTS questionnaire might give additional idea about CTS.  相似文献   
26.
Malign fibrous histiocytoma is one of the most observed soft tissue sarcomas seen in the adults. The most common metastasis region is the lung and metastasis. Mounier-Kuhn syndrome is characterized by the highly dilatation of the trachea and bronchi. We may encounter with the major airway obstruction in the endoluminal or extraluminal lung and mediastinal masses or those with both components together. In this article, we would like to highlight the occurrence of a rare seen clinical situation secondary to the giant mediastinal malign fibrous histiocytoma metastasis and the clinical difficulties experienced in resolving of the main airway obstruction caused by the mass. Since the lack of the similar studies conducted previously, we found the case worth presenting.  相似文献   
27.
Pseudohypoparathyroidism (PHP) is a rare disorder characterized by varying degrees of unresponsiveness to parathyroid hormone. Patients usually present with hypocalcemia-induced seizures or tetany, whereas no case of hypocalcemia-induced cardiac arrhythmia in PHP has been described to date. In this paper, we report the case of a male adolescent with PHP type 1a who presented with hypocalcemia-induced ventricular extrasystoles (bigeminy, trigeminy) and mild corrected QT interval prolongation. The patient had brachydactyly and his second fingers and toes were longer than the others, a finding consistent with PHP. Laboratory tests detected hypomagnesemia, as well as elevated levels of creatine kinase and lactate dehydrogenase. Ventricular arrhythmia and abnormal laboratory tests improved with calcium supplementation and vitamin D treatment. The findings in this patient suggest that hypomagnesemia may make patients with PHP more susceptible to hypocalcemia and may thus prompt a state of hypocalcemia-induced arrhythmia or other cardiac complications.  相似文献   
28.
29.
Purpose

We aimed to reveal whether static and dynamic pupillary responses can be used for the detection of autonomic nervous system (ANS) dysfunction in patients with obstructive sleep apnea syndrome (OSAS).

Methods

We included in this study patients with OSAS, who were divided into three groups according to the apnea–hypopnea index (AHI) (group 1, mild [n?=?20]; group 2, moderate [n?=?20]; and group 3, severe [n?=?20]), and healthy controls (group 4, n?=?20). Pupillary responses were measured using a pupillometry system.

Results

Static (mesopic PD, P?=?0.0019; low photopic PD, P?=?0.001) and dynamic pupil responses (resting diameter, P?=?0.004; amplitude of pupil contraction, P?<?0.001; duration of pupil contraction, P?=?0.022; velocity of pupil contraction, P?=?0.001; and velocity of pupil dilation, P?=?0.012) were affected in patients with different OSAS severities. Also, AHI was negatively correlated with mesopic PD (P?=?0.008), low photopic PD (P?=?0.003), resting diameter (P?=?0.001), amplitude of pupil contraction (P?<?0.001), duration of pupil contraction (P?=?0.011), velocity of pupil contraction (P?<?0.001), and velocity of pupil dilation (P?=?0.001).

Conclusion

We detected pupil responses innervated by the ANS were affected in the OSAS patients. This effect was more significant in the severe OSAS patients. Therefore, the pupillometry system can be an easily applicable, noninvasive method to detect ANS dysfunction in the OSA patients.

  相似文献   
30.
International Ophthalmology - The purpose of this study was to compare vitamin D (VD) deficiency frequency among patients with pterygium to that of healthy subjects and to investigate the VD...  相似文献   
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