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排序方式: 共有3513条查询结果,搜索用时 93 毫秒
91.
Nobuhiro Takemae Tung Nguyen Long Thanh Ngo Yasuaki Hiromoto Yuko Uchida Vu Phong Pham Tsutomu Kageyama Shizuko Kasuo Shinichi Shimada Yasutaka Yamashita Kaoru Goto Hideyuki Kubo Vu Tri Le Hung Van Vo Hoa Thi Do Dang Hoang Nguyen Tsuyoshi Hayashi Aya Matsuu Takehiko Saito 《Archives of virology》2013,158(4):859-876
The antigenicity of the influenza A virus hemagglutinin is responsible for vaccine efficacy in protecting pigs against swine influenza virus (SIV) infection. However, the antigenicity of SIV strains currently circulating in Japan and Vietnam has not been well characterized. We examined the antigenicity of classical H1 SIVs, pandemic A(H1N1)2009 (A(H1N1)pdm09) viruses, and seasonal human-lineage SIVs isolated in Japan and Vietnam. A hemagglutination inhibition (HI) assay was used to determine antigenic differences that differentiate the recent Japanese H1N2 and H3N2 SIVs from the H1N1 and H3N2 domestic vaccine strains. Minor antigenic variation between pig A(H1N1)pdm09 viruses was evident by HI assay using 13 mAbs raised against homologous virus. A Vietnamese H1N2 SIV, whose H1 gene originated from a human strain in the mid-2000s, reacted poorly with post-infection ferret serum against human vaccine strains from 2000-2010. These results provide useful information for selection of optimal strains for SIV vaccine production. 相似文献
92.
Shruti Vidhawan Agarwalla Kassapa Ellepola Nikolaos Silikas AH Castro Neto Chaminda Jayampath Seneviratne Vinicius Rosa 《Dental materials》2021,37(2):370-377
ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics. 相似文献
93.
Objective:
The spleen is more commonly affected in multiorgan disease, but alternative sites are selected for biopsy owing to perceived haemorrhage risk. If these sites are inaccessible or, less commonly, the spleen is the only disease site, then splenic biopsy is considered, with most studies using a 20- to 22-G needle. The primary aim of biopsy is to exclude underlying malignancy or to obtain histological analysis in known malignancy, usually lymphoma, when reclassification is required for therapy. We present, to our knowledge, the largest series of 18-G ultrasound-guided splenic core needle biopsy assessing diagnostic and complication rates.Methods:
All ultrasound-guided splenic biopsy cases from May 1990 to May 2015 were identified on the radiology information system. Histological diagnosis and complications were identified from laboratory reports, case notes and discharge summaries to assess diagnostic positive and complication rates. Haemorrhages requiring transfusion, embolization or splenectomy, pneumothorax, other significant intra-abdominal injury or death are classified as major complications, whilst conservative haemorrhage management is considered a minor complication.Results:
A total of 52 splenic biopsies were performed in 47 patients. A positive diagnostic yield for all biopsies was 90.4%. The major and minor complication rates were 0% and 1.9% (1/52), respectively.Conclusion:
Ultrasound-guided 18-G splenic biopsy is a safe and accurate procedure with no added risk of complications when compared with smaller needles or biopsy of other abdominal organs.Advances in knowledge:
This is the largest case series of ultrasound-guided splenic biopsy with an 18-G needle, and our experience confirms a high diagnostic yield and a complication rate which compares favourably with the biopsy of other abdominal organs. 相似文献94.
Chronic fetal hypoxia affects axonal maturation in guinea pigs during development: A longitudinal diffusion tensor imaging and T2 mapping study
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95.
TRA Lane HM Moore IJ Franklin AH Davies 《Annals of the Royal College of Surgeons of England》2015,97(2):e18-e20
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae. 相似文献
96.
Clinical significance and prediction factors of gastric varices in patients with hepatocellular carcinoma 总被引:1,自引:0,他引:1
Yeh JL Peng YC Tung CF Yang DY Hu WH Chow WK Yeh HZ Chen GH 《Hepato-gastroenterology》2003,50(53):1603-1608
BACKGROUND/AIMS: Hepatocellular carcinoma is part of the natural history of liver cirrhosis. Gastrointestinal bleeding and hepatic failure are the leading causes of death in hepatocellular carcinoma patients. With gastrointestinal bleeding, variceal bleeding is the most prominent, and most variceal bleeding is of esophageal origin. Gastric varices bleeding is often a massive and severe bleeding episode. The role of gastric varices among patients with hepatocellular carcinoma remains to be clarified. In this study, we aimed to evaluate the prevalence, clinical significance and prediction of gastric varices in patients with hepatocellular carcinoma. METHODOLOGY: From 1998 to 2000, we reviewed 304 patients with hepatocellular carcinoma receiving upper gastrointestinal endoscopic examinations. Patients' clinical characteristics, physical findings, laboratory data, image studies, endoscopic examinations and treatment were reviewed. RESULTS: Among 304 patients with HCC, twenty-one (6.9%) had gastric varices among 304 patients with hepatocellular carcinoma. The location of gastric varices were the posterior wall in 12 (57%), the lesser curvature in 1 (5%), the greater curvature in 4 (19%) and the fundus in 4 (19%). Three (14%) of these 21 patients with hepatocellular carcinoma and gastric varices had clinical evidence of bleeding. One of them died due to uncontrollable bleeding. Child-Pugh classification, hepatic encephalopathy, portal vein or splenic vein dilatation, ascites, splenomegaly, albumin level, prothrombin time and platelet count were significantly different between hepatocellular carcinoma patients with gastric varices and without gastric varices under the univariate analysis. Ascites (Odds ratio: 5.45; 95% confidence interval: 2.12-14.01) and portal vein or splenic vein dilatation (Odds ratio: 4.38; 95% confidence interval: 1.77-10.86) were the two most important predictors under the stepwise logistic regression analysis. CONCLUSIONS: The prevalence of gastric varices in patients with hepatocellular carcinoma is 6.9% and the risk of bleeding is low in this study. The Predictors of gastric varices among hepatocellular carcinoma are related to liver cirrhosis, Child-Pugh classification, hepatic encephalopathy, portal vein or splenic vein dilatation, ascites, splenomegaly, albumin level, prothrombin time and platelet count. 相似文献
97.
Objectives:To compare airway volumes and minimum cross-section area changes of Class III patients treated with bone-anchored maxillary protraction (BAMP) versus untreated Class III controls.Materials and Methods:Twenty-eight consecutive skeletal Class III patients between the ages of 10 and 14 years (mean age, 11.9 years) were treated using Class III intermaxillary elastics and bilateral miniplates (two in the infra-zygomatic crests of the maxilla and two in the anterior mandible). The subjects had cone beam computed tomographs (CBCTs) taken before initial loading (T1) and 1 year out (T2). Twenty-eight untreated Class III patients (mean age, 12.4 years) had CBCTs taken and cephalograms generated. The airway volumes and minimum cross-sectional area measurements were performed using Dolphin Imaging 11.7 3D software. The superior border of the airway was defined by a plane that passes through the posterior nasal spine and basion, while the inferior border included the base of the epiglottis to the lower border of C3.Results:From T1 to T2, airway volume from BAMP-treated subjects showed a statistically significant increase (1499.64 mm3). The area in the most constricted section of the airway (choke point) increased slightly (15.44 mm2). The airway volume of BAMP patients at T2 was 14136.61 mm3, compared with 14432.98 mm3 in untreated Class III subjects. Intraexaminer correlation coefficients values and 95% confidence interval values were all greater than .90, showing a high degree of reliability of the measurements.Conclusion:BAMP treatment did not hinder the development of the oropharynx. 相似文献
98.
Yang Zhou Chuan Hua He Erica L. Herzog Xueyan Peng Chang-Min Lee Tung H. Nguyen Mridu Gulati Bernadette R. Gochuico William A. Gahl Martin L. Slade Chun Geun Lee Jack A. Elias 《The Journal of clinical investigation》2015,125(8):3178-3192
Hermansky-Pudlak syndrome (HPS) comprises a group of inherited disorders caused by mutations that alter the function of lysosome-related organelles. Pulmonary fibrosis is the major cause of morbidity and mortality in patients with subtypes HPS-1 and HPS-4, which both result from defects in biogenesis of lysosome-related organelle complex 3 (BLOC-3). The prototypic chitinase-like protein chitinase 3–like–1 (CHI3L1) plays a protective role in the lung by ameliorating cell death and stimulating fibroproliferative repair. Here, we demonstrated that circulating CHI3L1 levels are higher in HPS patients with pulmonary fibrosis compared with those who remain fibrosis free, and that these levels associate with disease severity. Using murine HPS models, we also determined that these animals have a defect in the ability of CHI3L1 to inhibit epithelial apoptosis but exhibit exaggerated CHI3L1-driven fibroproliferation, which together promote HPS fibrosis. These divergent responses resulted from differences in the trafficking and effector functions of two CHI3L1 receptors. Specifically, the enhanced sensitivity to apoptosis was due to abnormal localization of IL-13Rα2 as a consequence of dysfunctional BLOC-3–dependent membrane trafficking. In contrast, the fibrosis was due to interactions between CHI3L1 and the receptor CRTH2, which trafficked normally in BLOC-3 mutant HPS. These data demonstrate that CHI3L1-dependent pathways exacerbate pulmonary fibrosis and suggest CHI3L1 as a potential biomarker for pulmonary fibrosis progression and severity in HPS. 相似文献
99.
Kevin Chiem Brooke A. Fuentes David L. Lin Tung Tran Alexis Jackson Maria S. Ramirez Marcelo E. Tolmasky 《Antimicrobial agents and chemotherapy》2015,59(9):5851-5853
The in vitro activity of the aminoglycoside 6′-N-acetyltransferase type Ib [AAC(6′)-Ib] was inhibited by CuCl2 with a 50% inhibitory concentration (IC50) of 2.8 μM. The growth of an amikacin-resistant Klebsiella pneumoniae strain isolated from a neonate with meningitis was inhibited when amikacin was supplemented by the addition of Zn2+ or Cu2+ in complex with the ionophore pyrithione. Coordination complexes between cations and ionophores could be developed for their use, in combination with aminoglycosides, to treat resistant infections. 相似文献