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91.
We aimed to quantitatively investigate the relationship between amplitude-based pulse-echo ultrasound parameters and early degeneration of the knee articular cartilage. Twenty samples from six human femoral condyles judged as grade 0 or 1 according to International Cartilage Repair Society grading were assessed using a 15-MHz pulsed-ultrasound 3-D scanning system ex vivo. Surface roughness (Rq), average collagen content (A1) and collagen orientation (A12) in the superficial zone of the cartilage were measured via laser microscopy and Fourier transform infrared imaging spectroscopy. Multiple regression analysis with a linear mixed-effects model (LMM) revealed that a time-domain reflection coefficient at the cartilage surface (Rc) had a significant coefficient of determination with Rq and A12 (RLMMm2=0.79); however, Rc did not correlate with A1. Concerning the collagen characteristic in the superficial zone, Rc was found to be a sensitive indicator reflecting collagen disorganization, not collagen content, for the early degeneration samples.  相似文献   
92.
Our knowledge about pulmonary complications of Beh?et's disease continues to evolve, but we need controlled trials for the management of the disease. The main goal should be to elucidate the pathogenesis and standardize the management according to the underlying pathologic process.  相似文献   
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Report is given about a case of Ptyalismus gravidarum. The data found in literature about the theories of etiology and the possibilities of therapy are discussed. The use of psycho-therapy is advised.  相似文献   
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Unintended pregnancies are accepted as associated with social, maternal and perinatal risks, but few data exist in South America. In a selected network of hospitals participating in the ECLAMC (Spanish acronym for Latin American Collaborative Study of Congenital Malformations), the frequency of unintended pregnancies was 49.8% in 5155 mothers of normal liveborns, as interviewed in the post-partum period (1992-1994). Compared with the intended pregnancy group, these mothers were more frequently multiparous, conceived easily, had a surprisingly higher mean maternal age, lower educational level, and Black ancestors. The frequency of mistimed pregnancies was the highest among primiparae. No adverse perinatal outcome could be found with regard to low birthweight (< 2500 g), prematurity (< 37 weeks), and early neonatal death. The rates of Caesarean delivery, twinning and sex ratio were similar in intended and unintended groups. Logistic regression analysis showed that maternal education could be a confounding factor associated with other maternal variables. The rate of unintended pregnancies in the present study is significantly higher than that described for other regions. Knowledge of the characteristics of women experiencing unintended pregnancies would allow proper public health strategies.   相似文献   
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STATEMENT OF THE PROBLEM: The ceramic composition and surface microstructure of all-ceramic restorations are important components of an effective bonding substrate. Hydrofluoric acid and sandblasting are well-known procedures for surface treatment; however, surface treatment for high alumina-containing and lithium disilicate ceramics have not been fully investigated. PURPOSE: This in vitro study evaluated the tensile bond strength of resin cement to two types of ceramic systems with different surface treatments. METHODS AND MATERIALS: Thirty specimens of each ceramic system were made according to the manufacturer's instructions and embedded in polyester resin. Specimens of In-Ceram Alumina [I] and IPS Empress 2 [E] were distributed to three groups with differing surface treatments (n = 10): sandblasting with 50 microm aluminum oxide (APA); sandblasting with 110 microm aluminum oxide modified with silica particles (ROCATEC System-RS); a combination of sandblasting with APA and 10% hydrofluoric acid etching (HA) for two minutes on In-Ceram and for 20 seconds for IPS Empress 2. After the respective surface treatments, all the specimens were silanated, and Rely-X resin cement was injected onto the ceramic surface and light polymerized. The specimens were stored in distilled water at 37 degrees C for 24 hours and thermally cycled 1,100 times (5 degrees C/55 degrees C). The tensile bond strength test was performed in a universal testing machine at a 0.5 mm/minute crosshead speed. RESULTS: The mean bond strength values (MPa) for IPS Empress 2 were 12.01 +/- 5.93 (EAPA), 10.34 +/- 1.77 (ERS) and 14.49 +/- 3.04 (EHA). The mean bond strength values for In-Ceram Alumina were 9.87 +/- 2.40 (IAPA) and 20.40 +/- 6.27 (IRS). All In-Ceram specimens treated with 10% hydrofluoric acid failed during thermal cycling. CONCLUSION: The Rocatec system was the most effective surface treatment for In-Ceram Alumina ceramics; whereas, the combination of aluminum oxide sandblasting and hydrofluoric acid etching for 20 seconds worked more effectively for Empress 2 ceramics.  相似文献   
99.
Background: Arteriovenous malformations are shunts between an artery and the venous system that lie within a nidus without an intervening capillary bed. These lesions are thought to be congenital, but recent reports have challenged this assumption. Case Report: A 50-year-old man presented to the emergency department with a generalized tonic-clonic seizure. Before the onset of his seizure, he experienced a vivid auditory hallucination of his favorite song by the band Pink Floyd, “A Brick in the Wall.” He had been diagnosed with epilepsy 25 years previously. On presentation, his neurological examination was normal, but a computed tomography scan of the brain revealed a large arteriovenous malformation (AVM) occupying the left temporal lobe. Upon more detailed questioning, he recalled that a brain angiogram had been performed 25 years before and was reported to be normal. Neurosurgery was not performed in view of the size of the malformation. The patient is being followed-up as an outpatient. Conclusion: AVMs may arise de novo and then spontaneously become symptomatic. Cerebral de novo AVM should be considered in the differential diagnosis in patients with complex auditory musical hallucinations or any new neuropsychiatric symptoms.  相似文献   
100.

Objective

Foreign body aspiration (FBA) is a serious problem in children. While bronchoscopy should be performed in all patients with aspiration; patients without aspiration should be carefully excluded to avoid an unnecessary bronchoscopy. In this study we analyzed the details of our series, complication rates and compared the diagnostic findings between patients with an aspirated FB and those without. We also calculated the sensitivities, specificities, positive predictive values and negative predictive values of clinical history, symptoms, physical examination findings and radiological findings in patients with suspected FBA (sFBA). Finally, we evaluated the validity of our bronchoscopy indications in these patients.

Methods

We reviewed the data of 207 patients who underwent rigid bronchoscopy for sFBA. We used clinical history, symptoms, physical examination and radiological findings as diagnostic findings. Complication rates in addition to these four diagnostic criteria constitute our indications for performing a rigid bronchoscopy.

Results

After excluding 15 patients with radiopaque FB or previous fiberoptic bronchoscopy, 138 of 192 patients had an aspirated foreign body. The sensitivity and specificity of clinical history, symptoms, physical examination findings and radiological findings were 90.5% and 24.1%, 97.8% and 7.4%, 96.4% and 46.3, and 71.7% and 74.1% respectively. There was only one major complication which caused moderate neurological sequelae. There was no mortality and no thoracotomy or tracheotomy requirement in this group.

Conclusions

While symptoms, physical examination findings and clinical history had high sensitivities, radiological findings had the highest specificity. Low specificities of clinical history, symptoms and physical examination findings were due to our expanded bronchoscopy indication, which aimed to include all patients with foreign body aspiration. Our low complication rate facilitated the expansion of bronchoscopy indications, even for patients with slight clinical suspicion.  相似文献   
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