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21.
Since a novel beta-coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first reported in December 2019, there has been a rapid global spread of the virus. Genomic surveillance was conducted on samples isolated from infected individuals to monitor the spread of genetic variants of SARS-CoV-2 in Korea. The Korea Disease Control and Prevention Agency performed whole genome sequencing of SARS-CoV-2 in Korea for 1 year (January 2020 to January 2021). A total of 2,488 SARS-CoV-2 cases were sequenced (including 648 cases from abroad). Initially, the prevalent clades of SARS-CoV-2 were the S and V clades, however, by March 2020, GH clade was the most dominant. Only international travelers were identified as having G or GR clades, and since the first variant 501Y.V1 was identified (from a traveler from the United Kingdom on December 22nd, 2020), a total of 27 variants of 501Y.V1, 501Y.V2, and 484K.V2 have been classified (as of January 25th, 2021). The results in this study indicated that quarantining of travelers entering Korea successfully prevented dissemination of the SARS-CoV-2 variants in Korea.  相似文献   
22.
Dual-energy X-ray absorptiometry (DXA)-based bone mineral density testing is standard to diagnose osteoporosis to detect individuals at high risk of fracture. A radiomics approach to extract quantifiable texture features from DXA hip images may improve hip fracture prediction without additional costs. Here, we investigated whether bone radiomics scores from DXA hip images could improve hip fracture prediction in a community-based cohort of older women. The derivation set (143 women who sustained hip fracture [mean age 73 years, time to fracture median 2.1 years] versus 290 age-matched women [mean age 73 years] who did not sustain hip fracture during follow-up [median 5.5 years]) were split into the train set (75%) and the test set (25% hold-out set). Among various models using 14 selected features out of 300 texture features mined from DXA hip images in the train set, random forest model was selected as the best model to build a bone radiomics score (range 0 to 100) based on the performance in the test set. In a community-based cohort (2029 women, mean age 71 years) as the clinical validation set, the bone radiomics score was calculated using a model fitted in the train set. A total of 34 participants (1.7%) sustained hip fracture during median follow-up of 5.4 years (mean bone radiomics score 40 ± 16 versus 28 ± 12 in non-fractured, p < 0.001). A one-point bone radiomics score increment was associated with a 4% elevated risk of incident hip fracture (adjusted hazard ratio [aHR] = 1.04, p = 0.001) after adjustment for age, body mass index (BMI), previous history of fracture, and femoral neck T-score, with improved model fit when added to covariates (likelihood ratio chi-square 10.74, p = 0.001). The association between bone radiomics score with incident hip fracture remained robust (aHR = 1.06, p < 0.001) after adjustment for FRAX hip fracture probability. Bone radiomics scores estimated from texture features of DXA hip images have the potential to improve hip fracture prediction. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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BackgroundUreaplasma parvum (UP) is commonly isolated in the genitor-urinary tract and may cause various clinical features, including microscopic hematuria (MH). Some UP serovars are more commonly related with specific urogenital disease, but the evidences have been conflicting. This study primarily aimed to research the possible associations between specific UP serotypes and genito-urinary pathogenicity in female patients showing MH with/without chronic micturition urethral pain (CMP).MethodsThis study retrospectively reviewed 276 female patients having MH with/without CMP, who visited health screening center or female infertility clinic. All patients underwent multiplex polymerase chain reaction (PCR) tests with vaginal and urine samples to evaluate the infection rate and serotypes of UP. The antimicrobial susceptibility of UP and the predictors of CMP among UP infected patients were also analyzed. All patients were followed up at least for 6-months.ResultsForty-nine patients (17.8%) showed urinary UP infection. Urinary UP serotyping showed the prevalence of seorvar-1, -3, -6 and -14 were 24.5%, 30.6%, 18.4% and 26.5%, respectively. 79.6% of the urinary UP positive patients accompanied vaginal UP infection. 22 patients of the cohort (8.0%) had CMP whereas serovars-3 and -14 accompanied CMP in 54.5% and 41.0% cases, respectively. No serovars-6 infection case had CMP. 26.4% of the cohort were infertile whereas 10.9% of these infertile patients were positive for urinary tract infection with UP serotype-3 or -14. Doxycycline, josamycin and pristinamycin were the most active antibiotics with the lowest rate of resistance (0.0%) for treating UP. At 1-month post-initial treatment with doxycycline, all UP serotypes were eradicated and no patient complained of urethral discomfort. However, simultaneous urinary and vaginal reinfection of serovar-3 (5 cases) and serovar-5 (1 case) were confirmed at 3-months post-initial doxycycline therapy. The logistic regression analyses revealed that serovars-3 [hazard ratio (HR) 1.354, P value 0.018] and -14 (HR 1.103, P value 0.046) were significantly associated with CMP in female patients having MH.ConclusionsUP serovars-3 and -14 infections could be associated with CMP in female patients having MH. Doxycycline, josamycin and pristinamycin were effective for treating UP. Serovar-3 showed higher reinfection rate than other serotypes after antibiotics treatment.  相似文献   
25.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation.  相似文献   
26.
PURPOSE: The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure. METHODS: We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively. RESULTS: Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis. CONCLUSION: Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation.  相似文献   
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28.
Urolithiasis in renal and combined pancreas/renal transplant recipients   总被引:6,自引:0,他引:6  
PURPOSE: Urological complications in renal transplant recipients will become more common with increasing numbers of transplantations as well as increased graft survival secondary to improvements in immunosuppression. Urinary stone disease may be one of those complications. We determine the current incidence of urinary stone disease in renal transplant patients based on contemporary immunosuppressive regimens. MATERIALS AND METHODS: We reviewed the records of 1,730 renal and 83 pancreas/renal transplantations performed during the cyclosporine era and identified 8 recipients (0.4%) with urinary stone disease, including 3 with renal pelvic stones, 1 with multiple ureteral stones and 4 with bladder calculi. RESULTS: Treatment ranged from conservative observation to open pyelolithotomy, and included percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy. The ureteral stones were removed with antegrade and retrograde ureteroscopy. The 4 bladder stones were treated with cystolithalopaxy. No case had significant permanent graft damage. Mean followup was 68.6 months. Mean serum creatinine was 1.5 mg./dl. (normal 0.5 to 1.3) at baseline and 2.38 after followup. CONCLUSIONS: While the incidence of upper tract urinary stone disease in renal (0.23%) and pancreas/renal (1.2%) transplant recipients is not statistically significant (p <0.45), the latter have significantly higher rates of bladder stones (4.8 versus 0%, p <0.001). The diagnosis of urinary stone disease in transplant recipients can be challenging because of the lack of symptoms but the treatment approach is the same as in the normal population.  相似文献   
29.
In many Western developed countries, the incidence of stomach cancer has declined dramatically. This decrease was an extraordinary, "unplanned triumph", especially when compared to other cancers. Stomach cancer is still the most prevalent malignant tumor in Korea. Most Koreans carry Helicobacter pylori in their stomach. Thus, a new hypothesis, based on the relationship between the host and Helicobacter pylori, is presented as the carcinogenesis of human stomach cancer. The reasons for why the N-nitrosamide hypothesis should be dismissed as the etiology of stomach cancer, and why the contemporarily available principles and practice of intervention strategies to rapidly decrease the surprisingly high prevalence rate of Helicobacter pylori infection are impractical at this moment, are explained. In order to introduce an alternative provisional strategy of the "planned triumph" for the population vulnerable to stomach cancer, vitamin C is defined as an anti-inflammatory agent on the basis of the pathogenesis of Helicobacter pylori infection.  相似文献   
30.
Minority status within any larger group is often difficult. Lesbian nurses face a dilemma of choice—whether or not to come out of the closet to their colleagues and patients. This essay describes the professional reflections of one lesbian nurse.  相似文献   
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