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41.
Magnetic resonance imaging (MRI) has become a crucial tool for evaluating mediastinal masses considering that several lesions that appear indeterminate on computed tomography and radiography can be differentiated on MRI. Using a three-compartment model to localize the mass and employing a basic knowledge of MRI, radiologists can easily diagnose mediastinal masses. Here, we review the use of MRI in evaluating mediastinal masses and present the images of various mediastinal masses categorized using the International Thymic Malignancy Interest Group''s three-compartment classification system. These masses include thymic hyperplasia, thymic cyst, pericardial cyst, thymoma, mediastinal hemangioma, lymphoma, mature teratoma, bronchogenic cyst, esophageal duplication cyst, mediastinal thyroid carcinoma originating from ectopic thyroid tissue, mediastinal liposarcoma, mediastinal pancreatic pseudocyst, neurogenic tumor, meningocele, and plasmacytoma.  相似文献   
42.
Epigenetic regulation by long noncoding RNAs in plants   总被引:1,自引:0,他引:1  
Many eukaryotes, including plants, produce a large number of long noncoding RNAs (lncRNAs). Growing number of lncRNAs are being reported to have regulatory roles in various developmental processes. Emerging mechanisms underlying the function of lncRNAs indicate that lncRNAs are versatile regulatory molecules. They function as potent cis- and trans-regulators of gene expression, including the formation of modular scaffolds that recruit chromatin-modifying complexes to target chromatin. LncRNAs have also been reported in plants. Here, we describe our current understanding on potential roles of lncRNA in plants.  相似文献   
43.
PurposeStreptococcus pneumoniae (S. pneumoniae) causes respiratory tract infections. Its non-vaccine serotypes and multidrug-resistant pneumococcal diseases have increased during the post-pneumococcal vaccination era. Therefore, it is important to understand the regional and age-related antimicrobial susceptibility of S. pneumoniae to select appropriate empirical antimicrobials.Materials and MethodsWe retrospectively studied trends in the antimicrobial resistance of S. pneumoniae to commonly prescribed antibiotics in patient groups of various ages at a single teaching hospital in Jeju Island from 2009 to 2018.ResultsIn total, 1460 S. pneumoniae isolates were obtained during the study period. The overall antimicrobial resistance rates of S. pneumoniae to penicillin, erythromycin, ceftriaxone, levofloxacin, and vancomycin were 16.2%, 84.7%, 25.9%, 3.3%, and 0.0%, respectively, and the MDR rate was 6.7%. Erythromycin and ceftriaxone resistance rates increased by years; however, they were significantly reduced in adult groups. Levofloxacin resistance and MDR rates were also higher in adult groups. Overall, the MDR rate significantly increased during the recent 10 years, as well as in patients with a history of hospitalization within 90 days [odds ratio (OR)=3.58, 95% confidence interval (CI)=1.91–6.71] and sinusitis (OR=4.98, 95% CI=2.07–11.96).ConclusionErythromycin and ceftriaxone resistance rates and the MDR rate of S. pneumoniae significantly increased during the recent 10 years; the trends in individual antimicrobial resistance rates significantly differed between the age groups. This study indicates the need for caution when using ceftriaxone as an empirical antimicrobial against pneumococcal infections.  相似文献   
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45.
Type 1 citrullinemia (CTLN1) often presents as a hyperammonemic encephalopathy in the neonatal period, but it can also develop in the late-infantile period and in adults. In addition, some patients can be identified in the presymptomatic period by neonatal or family member screening. In this study, twenty Korean patients with CTLN1 (19 families) were examined; fourteen patients with neonatal-onset, three with late-onset, and three that were identified presymptomatically. The 13 patients with hyperammonemic encephalopathy received continuous venovenous hemofiltration (CVVH) or peritoneal dialysis (PD). Although the hyperammonemia was relieved more effectively in the six patients on CVVH than the seven on PD, most of these patients suffered from severe neurologic deficits. Recurrent hyperammonemic episodes (7 pts, 35%), recurrent and reversible acute hepatic dysfunction (5 pts, 25%), and focal cerebral infarction (2 pts, 10%) were noted. The neonates with hyperammonemic encephalopathy had extensive brain injuries at the onset of hyperammonemia, followed by encephalomalacia and brain atrophy at quite an early age. Genetic testing for the ASS1 gene revealed a different mutation spectrum from those of other ethnicities; Three common mutations, c.421-2A > G (37.8%), c.1128-6_1188dup67 (18.9%), and p.Gly324Ser (16.2%), accounted for 73% of the mutations. The poor outcome was expected in patients with the peak ammonia level at onset over 600 μmol/L, whose proportion was higher in the neonatal presentation group than in the presymptomatic/late presentation group. Our findings add to the current understanding of the ethnic diversity of CTLN1 from both clinical and genetic perspectives.  相似文献   
46.
ObjectiveThe purpose of this study to develop new deep-brain stimulation system for long-term use in animals, in order to develop a variety of neural prostheses.MethodsOur system has two distinguished features, which are the fully implanted system having wearable wireless power transfer and ability to change the parameter of stimulus parameter. It is useful for obtaining a variety of data from a long-term experiment.ResultsTo validate our system, we performed pre-clinical test in Parkinson''s disease-rat models for 4 weeks. Through the in vivo test, we observed the possibility of not only long-term implantation and stability, but also free movement of animals. We confirmed that the electrical stimulation neither caused any side effect nor damaged the electrodes.ConclusionWe proved possibility of our system to conduct the long-term pre-clinical test in variety of parameter, which is available for development of neural prostheses.  相似文献   
47.
BACKGROUND: Electrocardiograms (ECGs) recorded from the higher intercostal spaces (ICSs) are reported to be helpful for the diagnosis of Brugada syndrome (BS). However, the prevalence of Brugada-type ECG changes recorded from the higher ICSs is unknown in the healthy Korean population. METHODS AND RESULTS: A total of 225 healthy Korean male subjects with a mean age of 44+/-13 (20-69) years with no syncope or family history of sudden death were enrolled in the present study. ECGs were taken from 4th, 3rd, and 2nd ICSs and examined for Brugada-type ECG changes. There were none on the routine 12-lead ECGs, but 3 (1.3%) of the 225 subjects had a Brugada-type ECG recorded from the higher ICSs and 1 of them had a Brugada-type ECG recorded at both the 2nd and 3rd ICSs. The prevalence of the Brugada-type ECG was 1.3% at the 3rd ICS, 0.4% at the 2nd ICS. All were type 2. CONCLUSION: Some healthy Korean males with normal routine ECGs show Brugada-type 2 changes on ECGs recorded from higher ICSs.  相似文献   
48.
[Purpose] The purpose of this study was to investigate the status of stroke in the Republic of Korea and its relationship with QOL based on standardized data. [Subjects and Methods] This study utilized raw data from the 2010 KCHS. In total, 229,229 individuals participated in the 2010 survey. The final analysis identified 4,604 individuals who had been diagnosed by a doctor with stroke. To identify the correlation between the aftereffect-related characteristics of stroke patients and QOL, a multiple linear regression analysis was performed. [Results] Participants experiencing aftereffects had a statistically significantly lower QOL than participants who had not experienced aftereffects. Regarding the types of aftereffects, participants experiencing palsy in the arms and legs, facial palsy, communication disabilities, swallowing or eating disabilities, and visual disabilities had a statistically significantly lower QOL than participants without aftereffects. The QOL of participants with one, two, three, four, or five aftereffects was statistically significantly less than that of participants without aftereffects [Conclusion] Stroke directly influences QOL and the number of types of aftereffects experienced by patients. Therefore, it is highly important that physical therapists seek to end the occurrence of one or more types of aftereffects in stroke patients.Key words: Stroke, Quality of life, Korean community healthy survey  相似文献   
49.
[Purpose] The purpose of this study was to observe the effects of stretching the upper trapezius muscle on the asymmetric rate of bite force. [Subjects] Forty-seven female university students who had all their original teeth, had no disorders in the temporomandibular joints, and had never worn braces; participated in this study. [Methods] An occlusometer was used to measure biting forces. Subsequently, stretching exercises of the upper trapezius were performed. The subjects were divided into 3 groups at the start of the testing: the asymmetric rate of the first group was less than 10%; the asymmetric rate of the second group was between 10% and 20%; and the asymmetric rate of the third group was more than 20%. The stretching exercises were done on the dominant side of the upper trapezius. [Results] After the stretching exercises of the upper trapezius, the results showed that for the first group, whose asymmetric rate of biting force was less than 10%, there was a significant increase in asymmetric rate (from 5.1% to 10.3%). For the second group, whose asymmetric rate of biting force was measured to be between 10% and 20%, the asymmetric rate decreased from 14.7% to 14.3%, but the change was not statistically significant. For the third group, whose asymmetric rate of biting force was more than 20%, there was a significant decrease in asymmetric rate (from 27.8% to 12.6%). [Conclusion] We concluded that stretching exercises of the upper trapezius muscle had a direct effect on the asymmetric rate of biting force.Key words: Asymmetric rate of biting force, Upper trapezius, Stretching exercise  相似文献   
50.

Background

Unstable simple elbow dislocation (USED) repair is challenged by the maintenance of joint reduction; hence, primary repair or reconstruction of disrupted ligaments is required to maintain the congruency and allow early motion of the elbow. We evaluated the effectiveness and the outcome of lateral collateral ligament (LCL) complex repair with additional medial collateral ligament (MCL) repair in cases of USED.

Methods

We retrospectively reviewed 21 cases of diagnosed USED without fractures around the elbow that were treated with primary ligament repair. In all cases, anatomical repair of LCL complex with or without common extensor origin was performed using suture anchor and the bone tunnel method. Next, the instability and congruency of elbow for a full range of motion were evaluated under the image intensifier. MCL was repaired only if unstable or incongruent elbow was observed. Clinical outcomes were evaluated using the Mayo elbow performance score (MEPS) and radiographic outcomes on last follow-up images.

Results

All cases achieved a stable elbow on radiographic and clinical results. LCL complex repair alone was sufficient to obtain the stable elbow in 17 of 21 cases. Four cases required additional MCL repair after restoration of the LCL complex. The overall mean MEPS was 91 (range, 70 to 100): excellent in 12 cases, good in 7 cases, and fair in 2 cases. All 17 cases with LCL complex repair only and 2 of 4 cases with additional MCL repair had excellent or good results by MEPS.

Conclusions

USED requires surgical treatment to achieve a congruent and stable joint. If the repair of lateral stabilizer such as LCL complex acquires enough joint stability to maintain a full range of motion, it may not be necessary to repair the medial stabilizer in all cases of USED.  相似文献   
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