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61.
62.
Do T. Nga Anh D. Phan Vu D. Lam Lilia M. Woods Katsunori Wakabayashi 《RSC advances》2020,10(47):28447
The photothermal energy conversion in hanging and floating polyaniline (PANi)-cotton fabrics is investigated using a model based on the heat diffusion equation. Perfect absorption and anti-reflection of wet hanging PANi-cotton fabrics cause quick transfer of total incident light into water confining nearly 100% of the sunlight. As a result, a hanging membrane is found to have more attractive properties than a floating above water fabric. We find, however, that the photothermal properties of a floating PANi-cotton membrane can greatly be enhanced by dispersing TiN nanoparticles in the water below the fabric. The calculated temperature gradients for TiN nanoparticle solutions show that the absorbed energy grows with increasing the nanoparticle density and that the photothermal process occurs mostly near the surface. The collective heating effects depend on the size and density of nanoparticles, which can further be used to modulate the photothermal process.The photothermal energy conversion in hanging and floating polyaniline (PANi)-cotton fabrics is investigated using a model based on the heat diffusion equation. 相似文献
63.
Congenital lobar emphysema (CLE) is characterized by overdistension and air-trapping in the affected lobe, and is one of the causes of infantile respiratory distress. In this report, we review our 27 years of experience with 30 CLE patients. Patients' medical records were evaluated with regard to age, clinical presentation, diagnostic methods, associated diseases, treatment, histopathologic findings, and final clinical and laboratory findings at the end of a long-term period. The mean age of 30 patients (18 male) at diagnosis was 4.9 +/- 6.7 months (range, 2 days-2.5 years). Tachypnea, dyspnea, cough, cyanosis, wheezing, hoarseness, and decreased breath sounds on the affected side were the main symptoms and clinical findings. On chest X-rays, emphysema was seen in all patients; shift/herniation to the opposite lung, atelectasis, and pneumothorax were observed in 16, 5, and 2 cases, respectively. Computerized tomography of the thorax was performed in 16 cases and revealed emphysema at affected lobe/lobes in all, a shift/herniation to the opposite side in 12 cases, and atelectasis of neighbor lobe/lobes in 7 cases. All 8 patients who had perfusion scintigraphy showed reduced perfusion in the affected lobe. Narrowed and flaccid bronchi were detected in one patient by using flexible bronchoscopy. Blood gas analysis was performed in 11 patients, and hypoxia and hypercarbia were revealed in 9 and 7 of these patients, respectively. The most common affected lobe was the left upper lobe (57%), followed by the right upper lobe (30%) and right middle lobe (27%). Two lobes were involved in 4 patients. Associated abnormalities were observed in 5 patients. Twenty-one patients underwent lobectomy; 9 were followed conservatively. Ages at diagnosis were significantly younger in surgically treated patients. Emphysema was detected in all pathological specimens, with an additional bronchial cartilage deficiency in 2 patients. In the surgically treated group, 2 patients died and 2 patients were lost to follow-up. In the conservatively treated group, one patient was lost to follow-up. Mean follow-up duration of all patients was 63.2 +/- 56.2 months (range, 1-209 months). At follow-up visits, all patients were doing well. In surgically treated patients, chest X-rays were normal (9 cases), or showed hyperlucency on the operated side (6 cases) or chronic changes in the operation area (2 cases). Hyperexpansion in the affected lobe was found to be reduced in all cases in the conservatively treated group. 相似文献
64.
Recombinant human thyrotropin‐stimulated thyroglobulin level at the time of radioactive iodine ablation is an independent prognostic marker of differentiated thyroid carcinoma in the setting of prophylactic central neck dissection 下载免费PDF全文
65.
66.
Endoscopic prediction of recurrence in patients with early gastric cancer after margin‐negative endoscopic resection 下载免费PDF全文
67.
Sumanadasa SD Goodman CD Lucke AJ Skinner-Adams T Sahama I Haque A Do TA McFadden GI Fairlie DP Andrews KT 《Antimicrobial agents and chemotherapy》2012,56(7):3849-3856
Histone deacetylase (HDAC) enzymes posttranslationally modify lysines on histone and nonhistone proteins and play crucial roles in epigenetic regulation and other important cellular processes. HDAC inhibitors (e.g., suberoylanilide hydroxamic acid [SAHA; also known as vorinostat]) are used clinically to treat some cancers and are under investigation for use against many other diseases. Development of new HDAC inhibitors for noncancer indications has the potential to be accelerated by piggybacking onto cancer studies, as several HDAC inhibitors have undergone or are undergoing clinical trials. One such compound, SB939, is a new orally active hydroxamate-based HDAC inhibitor with an improved pharmacokinetic profile compared to that of SAHA. In this study, the in vitro and in vivo antiplasmodial activities of SB939 were investigated. SB939 was found to be a potent inhibitor of the growth of Plasmodium falciparum asexual-stage parasites in vitro (50% inhibitory concentration [IC(50)], 100 to 200 nM), causing hyperacetylation of parasite histone and nonhistone proteins. In combination with the aspartic protease inhibitor lopinavir, SB939 displayed additive activity. SB939 also potently inhibited the in vitro growth of exoerythrocytic-stage Plasmodium parasites in liver cells (IC(50), ~150 nM), suggesting that inhibitor targeting to multiple malaria parasite life cycle stages may be possible. In an experimental in vivo murine model of cerebral malaria, orally administered SB939 significantly inhibited P. berghei ANKA parasite growth, preventing development of cerebral malaria-like symptoms. These results identify SB939 as a potent new antimalarial HDAC inhibitor and underscore the potential of investigating next-generation anticancer HDAC inhibitors as prospective new drug leads for treatment of malaria. 相似文献
68.
Beom Kyung Kim Kwang‐Hyub Han Jun Yong Park Sang Hoon Ahn Ja Kyung Kim Yong Han Paik Kwan Sik Lee Chae Yoon Chon Do Young Kim 《Liver international》2010,30(6):860-866
Backgrounds: Periodic endoscopic screening for oesophageal varices (OVs) and prophylactic treatment for high‐risk OVs (HOVs; medium/large OVs or small OVs plus red sign/decompensation) are currently recommended for all cirrhotic patients. However, if a simple, noninvasive test is available, many low‐risk patients may reliably avoid endoscopy. Aims: We conducted a large‐scale validation study of a simple, noninvasive test called P2/MS based on complete blood counts, (platelet count)2/[monocyte fraction (%) × segmented neutrophil fraction (%)], and compared it with other predictive tests for HOVs in B‐viral cirrhotic patients. Methods: From 2008 to 2009, we prospectively enrolled 318 consecutive B‐viral cirrhotic patients. All underwent endoscopy and laboratory evaluation. Results: An area under the receiver operating characteristic curve of P2/MS was 0.941 for HOVs, comparable with those of the age–spleen platelet ratio index (0.922, P=0.317) and spleen–platelet ratio index (0.922, P=0.324), and better than those of age–platelet index (0.653, P<0.001), aspartate aminotransferase (AST)–platelet ratio index (0.871, P<0.006) and AST‐alanine aminotransferase ratio (0.644, P<0.001). P2/MS<11 reliably identified 83 patients as having HOVs (94.0% positive predictive value), while at a cutoff of 25 and 179 as not having HOVs (94.4% negative predictive value). Overall, P2/MS reliably determined the likelihood of HOVs in 262 patients (82.4%). These cutoffs were validated internally using bootstrap resampling methods, which showed good agreement. Conclusions: P2/MS is a simple, accurate and economical method, reducing the need for endoscopy in B‐viral cirrhosis. Patients with P2/MS<11 should be considered for appropriate prophylactic treatments, while those with P2/MS>25 may avoid endoscopy reliably. 相似文献
69.
Murat Akyildiz Fulya Gün?ar Sinan Akay Ba?ak Do?anav?argil Omer Ozütemiz 《The Turkish journal of gastroenterology》2006,17(4):298-299
Liver penetration is a rare complication of peptic ulcer disease. Histopathological examination of endoscopic biopsy is essential for diagnosis as well as sonographic and computerized tomography imaging. Endoscopic examination could not exclude tumor without pathologic examination. Herein, we report a patient diagnosed as duodenal ulcer penetration into liver by endoscopic biopsy. 相似文献
70.
Tolga Demirba? Necdet Güler Cemil Cali?kan Bari? Gürcü Ba?ak Do?anav?argil Mustafa Korkut 《The Turkish journal of gastroenterology》2006,17(4):305-307
Colon hemangiomas are rare benign vascular lesions which are usually seen in teenagers. The frequent presentation is repetitive painless rectal bleeding. Colonic hemangiomas are occasionally found in the rectosigmoid area. A 62-year-old male patient was admitted to the hospital with the complaints of mechanical bowel obstruction. The radiological imaging techniques revealed a transverse colon tumor. Consequently, the patient was operated, and transverse colectomy and end-to-end anastomosis were performed. No postoperative complications occurred. The pathologic examination revealed cavernous hemangioma of the transverse colon. This report describes a very rare case of bowel obstruction due to colonic hemangioma. 相似文献