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991.
992.
Suh-Young Lee Soon Ho Yoon Woo-Jung Song So-Hee Lee Hye-Ryun Kang Sun-Sin Kim Sang-Heon Cho 《Allergy, asthma & immunology research》2014,6(4):310-315
Purpose
Upper and lower respiratory tract pathologies are believed to be interrelated; however, the impact of upper airway inflammation on lung function in subjects without lung disease has not been evaluated. This study investigated the association of CT finding suggesting chronic sinusitis and lung function in healthy subjects without lung disease.Methods
This was a retrospective study of prospectively collected data from 284 subjects who underwent a pulmonary function test, bronchial provocation test, rhinoscopy, and osteomeatal unit computed tomography offered as a private health check-up option.Results
CT findings showed that the sinusitis group had a significantly lower FEV1/FVC ratio than subjects without sinusitis finding (78.62% vs 84.19%, P=0.019). Among the sinusitis group, subjects classified by CT findings as the extensive disease group had a slightly lower FEV1/FVC than those of the limited disease group (76.6% vs 79.5%, P=0.014) and the associations were independent of the presence of airway hyperresponsiveness. The subjects with nasal polyp had also lower FEV1 and FEV1/FVC than subjects without nasal polyp (FEV1: 100.0% vs 103.6%, P=0.045, FEV1/FVC: 77.4% vs 80.0%, P=0.005).Conclusions
CT findings suggesting chronic sinusitis and nasal polyp were associated with subclinical lower airway flow limitation even in the absence of underlying lung disease. 相似文献993.
Transition metal oxides are commonly used in electrochemical energy storage materials, but there are still many drawbacks that impede a wide range of applications. Heteroatom doping can significantly improve its performance. Herein, we have successfully prepared highly uniform N-doped NiCo2O4@C hollow nanostructures for supercapacitors by a two-step hydrothermal treatment associated with successive annealing process. Prepared N-doped NiCo2O4@C materials exhibited an admirable specific capacitance of 1028 F g−1 at a current density of 3 A g−1, with 625 F g−1 remaining even at high current density of 20 A g−1. Besides, this composite showed good electrochemical stability with capacity retention of 84% after 5000 cycles repetitive galvanostatic charge–discharge test at 10 A g−1. An asymmetric supercapacitor was assembled by the N-doped NiCo2O4@C electrode, attached activate carbon (AC) as a counter electrode, exhibiting a high energy density of 26.67 W h kg−1 at a power density of 402 W kg−1. The improvement of electrochemical performance is ascribed to the co-doping of nitrogen and carbon atoms. These results indicate that N-doped NiCo2O4@C can be employed as an ideal electrode material for electrochemical energy storage.Procedure for fabricating N-doped NiCo2O4@C hollow nanostructures. 相似文献
994.
Kyungtae Ko In Gab Jeong Woo Suk Choi Ju Hyun Lim Ja Hee Suh Ja Hyeon Ku Yangsoon Park Kyung Cheol Moon Hyeon Hoe Kim Choung-Soo Kim Cheol Kwak 《International journal of clinical and experimental pathology》2014,7(9):6141-6148
The long-term mortality risk from prostate cancer increases in lymph node (LN) positive patients. This study was done to assess the effect of lymph node Gleason score (LNGS) on prognosis in patients with LN-positive prostate cancer. Among the 1,415 patients who received pelvic lymph node dissection (PLND), 117 (8.4%) patients had a positive LN. The PGS of the prostate specimens and the LNGS of the positive LNs were assessed by uropathologists. The median age of patients at surgery was 67 years (interquartile range [IQR], 62-71 years) and the median follow-up duration was 44.3 months (IQR, 27.0-78.5 months). Pathologic Gleason scores (PGS) of 6-9 included one (0.9%), 53 (49.5%), 22 (20.6%), and 31 (29.0%) patients. The median total number of retrieved LNs was 9.0 (IQR, 5.3-12.8). The median number of positive LNs was one (IQR, 1-2). Cancer architecture with a Gleason pattern and score were observed in LNs as in ordinary prostate specimens. LNGS 6-9 included nine (8.1%), 57 (51.4%), 31 (27.9%), and 14 (12.6%) patients. The speaman’s analysis showed the meaningful correlation between PGS and LNGS (P = 0.249, P = 0.011). The univariate analysis showed that the number of positive LNs and LNGS were significantly associated with prostate cancer-specific survival (P = 0.028; P = 0.005). The same architecture that is seen in the prostate was seen in positive LNs, and LNGS may be a significant prognostic factor in patients with LN-positive prostate cancer. 相似文献
995.
The reaction of aluminum and water is widely used in the field of propulsion and hydrogen production, but its reaction characteristics at the nanometer scale have not been fully studied. In this paper, the effect of particle size and surface passivation of aluminum particle on the reaction mechanism was studied by using reactive molecular dynamics (RMD) simulation. The reduction of aluminum particle size can accelerate the reaction rate in the medium term (20–80 ps) due to the increase of activity, but it also produces an agglomeration effect as the temperature increases. The presence of surface passivation reduces the proportion of active aluminum and the yield of hydrogen decreases by 30% and 33%, respectively, as the particle size decreases from 2.5 nm to 1.6 nm. The addition of AlH3 can overcome these drawbacks when some aluminum powders are replaced by AlH3. The hydrogen yield is increased by the reaction 2AlH3 + 3H2O → Al2O3 + 6H2. In the reaction of surface passivated Al (1.6 nm in diameter) and H2O, when the proportion of AlH3 reaches 25%, the energy release and hydrogen yield increase from 59.47 kJ mol−1 and 0.0042 mol g−1 to 142.56 kJ mol−1 and 0.0076 mol g−1, respectively. This performance even approximates the reaction of pure aluminum with water: 180.67 kJ mol−1 and 0.0087 mol g−1. In addition, the surface passivation affects the reaction mechanism. Before the passivation layer melts, the reaction 4Al + Al2O3 → 3Al2O occurs inside the nanoparticles.The temperature distribution, number of Al–O bonds and hydrogen yield evolution with time. 相似文献
996.
Nae-Yun Heo Young-Suk Lim Woochang Lee Minkyung Oh Jiyun An Danbi Lee Ju Hyun Shim Kang Mo Kim Han Chu Lee Yung Sang Lee Dong Jin Suh 《Clinical and molecular hepatology》2014,20(2):177-184
Background/Aims
There are few available data regarding the association between the single nucleotide polymorphisms (SNPs) of the gene encoding interleukin 28B (IL28B) and a sustained virologic response (SVR) to peginterferon (PEG-IFN) plus ribavirin (RBV) therapy in Korean chronic hepatitis C patients.Methods
This was a retrospective cohort study of 156 patients with chronic hepatitis C virus (HCV) infection who received combination treatment of PEG-IFN plus RBV. Blood samples from these patients were analyzed to identify the IL28B SNPs at rs12979860, rs12980275, rs8099917, and rs8103142. Association analyses were performed to evaluate the relationships between each IL28B SNP and SVRs.Results
Seventy six patients with HCV genotype 1 and 80 with genotype non-1 were enrolled. The frequencies of rs12979860 CC and CT genotypes were 90.4% and 9.6%, respectively; those of rs12980275 AA and AG genotypes were 87.2% and 12.8%, respectively; those of rs8099917 TT and TG genotypes were 92.3% and 7.7%, respectively; and those of rs8103142 TT and CT genotypes were 90.4% and 9.6%, respectively. Among the patients with HCV genotype 1, the SVR rates were 69.7% and 80.0% for rs12979860 CC and CT, respectively (P=0.71). Among the HCV genotype non-1 patients, SVR rates were 88.0% and 100% for rs12979860 CC and CT (P=1.00), respectively.Conclusions
Genotypes of the IL28B SNP that are known to be favorable were present in most of the Korean patients with chronic hepatitis C in this study. Moreover, the IL28B SNP did not influence the SVR rate in either the HCV genotype 1 or non-1 patients. Therefore, IL28B SNP analysis might be not useful for the initial assessment, prediction of treatment outcomes, or treatment decision-making of Korean chronic hepatitis C patients. 相似文献997.
Yun Jung Choi Jeong Han Kim Ja Kyung Koo Cho I Lee Ji Young Lee Jae Hoon Yang Soon Young Ko Won Hyeok Choe So Young Kwon Chang Hong Lee 《Clinical and molecular hepatology》2014,20(2):185-191
Background/Aims
A revised classification system for renal dysfunction in patients with cirrhosis was proposed by the Acute Dialysis Quality Initiative and the International Ascites Club Working Group in 2011. The aim of this study was to determine the prevalence of renal dysfunction according to the criteria in this proposal.Methods
The medical records of cirrhotic patients who were admitted to Konkuk University Hospital between 2006 and 2010 were reviewed retrospectively. The data obtained at first admission were collected. Acute kidney injury (AKI) and chronic kidney disease (CKD) were defined using the proposed diagnostic criteria of kidney dysfunction in cirrhosis.Results
Six hundred and forty-three patients were admitted, of whom 190 (29.5%), 273 (42.5%), and 180 (28.0%) were Child-Pugh class A, B, and C, respectively. Eighty-three patients (12.9%) were diagnosed with AKI, the most common cause for which was dehydration (30 patients). Three patients had hepatorenal syndrome type 1 and 26 patients had prerenal-type AKI caused by volume deficiency after variceal bleeding. In addition, 22 patients (3.4%) were diagnosed with CKD, 1 patient with hepatorenal syndrome type 2, and 3 patients (0.5%) with AKI on CKD.Conclusions
Both AKI and CKD are common among hospitalized cirrhotic patients, and often occur simultaneously (16.8%). The most common type of renal dysfunction was AKI (12.9%). Diagnosis of type 2 hepatorenal syndrome remains difficult. A prospective cohort study is warranted to evaluate the clinical course in cirrhotic patients with renal dysfunction. 相似文献998.
Su Jung Baik Kwon Yoo Tae Hun Kim Il Hwan Moon Min-Sun Cho 《Clinical and molecular hepatology》2014,20(2):208-213
Obstructive jaundice caused by tuberculous lymphadenitis is a rare manifestation of tuberculosis (TB), with 15 cases having been reported in Korea. We experienced a case of obstructive jaundice caused by pericholedochal tuberculous lymphadenitis in a 30-year-old man. The patient''s initial serum total bilirubin level was 21.1 mg/dL. Abdominal computed tomography revealed narrowing of the bile duct by a conglomerated soft-tissue mass involving the main portal vein. Abrupt obstruction of the common bile duct was observed on cholangiography. Pathologic analysis of a ultrasonography-guided biopsy sample revealed chronic granulomatous inflammation, and an endoscopic examination revealed esophageal varices and active duodenal ulceration, the pathology of which was chronic noncaseating granulomatous inflammation. Hepaticojejunostomy was performed and pathologic analysis of the conglomerated soft-tissue mass revealed chronic granulomatous inflammation with caseation of the lymph nodes. Tuberculous lymphadenitis should be considered in patients presenting with obstructive jaundice in an endemic area. 相似文献
999.
1000.
Yang-Hyun Kim Do-Hoon Kim Kyung Sook Lim Byung-Joon Ko Byung-Duck Han Ga-Eun Nam Yong-Gyu Park Kyung Do Han Jung-Hyun Kim Kyung-Hwan Cho 《Clinical oral investigations》2014,18(5):1517-1524