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81.
Toshiyuki Uryu Katsuhiro Ito Ken-Ichi Kobayashi Kei Matsuzaki 《Macromolecular chemistry and physics.》1979,180(6):1509-1519
In order to elucidate the catalytic behavior of phosphorus pentafluoride in the polymerization of anhydro sugars, 13P and 19F NMR spectra were measured on a reaction mixture of 1,6-anhydro-2,3,4-tri-O-benzyl-β-D -glucopyranose (LGTBE) and PF5 with different mole ratios in a temperature range of ?40 to ?80°C. In the 31P NMR spectrum measured at low temperatures, there was a total of 16 peaks, which consisted of a broad quintet, a septet, and a sharp quartet, being assigned to the PF4O-group, to PF, and to POF3, respectively. These fluoro compounds were also determined by the 19F NMR spectrum of the reaction mixture. The concentration of PF ions was found to correspond to that of oxonium ions, which are assumed to be actual propagating species, by determining both the concentration of PF from 19F NMR spectrum and the degree of polymerization of 2,3,4-tri-O-benzyl-α-D -glucopyranan obtained. Formation of the PF5: LGTBE complex was observed from the 31P NMR spectrum of the polymerization system at ?80°C, which exhibits a broad sextet as well as absorptions due to POF3, PF4O–, and PF. To confirm the PF5:LGTBE complex, the NMR measurement of the PF5: tetrahydropyran complex was carried out. A polymerization mechanism of LGTBE by PF5 catalyst is discussed on the basis of the NMR measurement of the polymerization system. 相似文献
82.
Hematopoietic cytokines such as interleukin (IL)-3, IL-5, and granulocyte macrophage colony-stimulating factor (GM-CSF) play a fundamental role in eosinophil functions in allergic asthma. The intracellular signal transduction mechanisms of these cytokines regulating the activation of eosinophils have been potential therapeutic targets. We investigated the roles of p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-kappaB) in IL-3, IL-5, and GM-CSF-induced adhesion, morphological changes, and subsequence transmigration of human eosinophils. IL-3, IL-5, and GM-CSF could augment the phosphorylation of p38 MAPK and nucleus translocation of NF-kappaB in eosinophils. cDNA expression arrays demonstrated that the gene expression levels of several adhesion molecules including intercellular adhesion molecule-1 (ICAM-1), alpha6, beta2 integrin (CD18), and CD44 were upregulated by these cytokines. Results from functional assays showed that adhesion of eosinophils onto airway epithelial cells was enhanced after IL-3 and IL-5 but not GM-CSF stimulation. These cytokines could markedly induce shape change and augment the transmigration of eosinophils. Moreover, administration of either p38 MAPK inhibitor, SB 203580, or proteasome inhibitor, N-cbz-Leu-Leu-leucinal (MG-132), could inhibit the cytokine-induced adhesion, shape change, and transmigration of eosinophils. Together, our findings suggest that IL-3, IL-5, and GM-CSF regulated the adhesion and chemotaxis of human eosinophils through shared signaling pathways involving both p38 MAPK and NF-kappaB. Our results therefore shed light on the further development of more effective agents for allergic and inflammatory diseases. 相似文献
83.
Tse GM Tsang AK Putti TC Scolyer RA Lui PC Law BK Karim RZ Lee CS 《Journal of clinical pathology》2005,58(2):185-189
BACKGROUND/AIMS: CD10 (CALLA) has recently been reported to be expressed in spindle cell neoplasia, and has been used to differentiate endometrial stromal sarcoma from leiomyoma and leiomyosarcoma. In the breast, myoepithelial cells express CD10, but there are few studies of the expression of CD10 in mammary fibroepithelial lesions. METHODS: Stromal CD10 expression was studied in 181 mammary phyllodes tumours (102 benign, 51 borderline malignant, and 28 frankly malignant) and 33 fibroadenomas using immunohistochemistry, to evaluate whether differences in expression correlated with the degree of malignancy. RESULTS: There was a progressive increase in the patients' age and tumour size, from fibroadenoma to phyllodes tumours with an increasing degree of malignancy (p < 0.001). Stromal CD10 expression was positive in one of 33 fibroadenomas, six of 102 benign phyllodes tumours, 16 of 51 borderline malignant phyllodes tumours, and 14 of 28 frankly malignant phyllodes tumours. The difference was significant (p < 0.001) and an increasing trend was established. Strong staining was seen in subepithelial areas with higher stromal cellularity and activity. Stromal CD10 expression had a high specificity (95%) for differentiating between benign lesions (fibroadenomas and benign phyllodes tumours) and malignant (borderline and frankly malignant) phyllodes tumours. CONCLUSIONS: CD10 may be a useful adjunct in assessing malignancy in mammary fibroepithelial lesions. 相似文献
84.
Chung Y. Lui Myung G. Lee Win L. Chiou 《Journal of pharmacokinetics and pharmacodynamics》1984,12(6):597-610
The effects of plasma concentration and pH on the steady-state volume of distribution, Vss,of methotrexate (MTX) were studied in five conditioned male beagle-mongrel dogs. Steady-state plasma MTX concentrations of approximately 1, 20, and 100g/ml were targeted for by i.v. bolus doses followed by i.v. infusions. An isotonic solution of sodium bicarbonate or ammonium chloride was simultaneously infused for the purpose of inducing plasma pH change, while the infusion of an isotonic solution of sodium chloride served as a control. Plasma and urine concentrations of MTX were quantitated by a sensitive high-performance liquid chromatographic method, and the Vss
of MTX was estimated by a recently reported physiologically based method of Chiou and Lam. Statistically significant (p<0.05) concentration and plasma pHdependent Vss
of MTX were observed. Concentration dependence of Vss
was noted in sodium chloride and ammonium chloride infused dogs, but not in bicarbonate treated dogs. There was an average 50.0 and 44.8% increase in Vss
at 1 g/ ml relative to the two higher concentrations (20 and 100 g/ ml) for dogs treated with ammonium and sodium chloride, respectively. However, Vss
of MTX at the targeted concentrations of 20 and 100 g/ml was relatively constant. Plasma pHdependence of Vss
was observed only at the plasma concentration of 1 g/ml, and on the average, ammonium chloride and sodium chloride treatments resulted in 50.0 and 31.3% higher Vss,respectively, when compared with the bicarbonate treatment. These phenomena appear to be adequately explained by the reported tissue uptake kinetics of MTX.This research was supported in part by a grant from the National Cancer Institute, CA-29754.Abstracted from a dissertation submitted in 1984 by Chung Y. Lui to the Graduate College, University of Illinois at Chicago, in partial fulfillment of Doctor of Philosophy Degree requirements. 相似文献
85.
目的探讨检测血乳酸、降钙素原和联合检测对急性一氧化碳中毒后迟发性脑病(DEACMP)的预测价值。 方法随机抽取我院在急诊科收住院的ACMP患者70例,随访3个月,以其中发生DEACMP患者10例为DEACMP组,其余60例为非DEACMP组,随机抽取同期笔者医院40例健康体检者为对照组。对患者立即行动脉血Lac和血清PCT检测,并计算Lac和PCT诊断DEACMP的灵敏度、特异度。 结果DEACMP组血Lac和PCT检测值均明显高于非DEACMP和对照组,差异有统计学意义(采用秩和检验,P<0.05);检测异常率亦明显高于非DEACMP组及对照组,差异有统计学意义(采用χ2检验,P<0.05)。Lac和PCT升高预测DEACMP的敏感度均为90.0% ,特异度分别为50.0%和65.0% ,准确性分别为55.7%和68.6%。联合检测时若其中1个指标为阳性时即预测DEACMP发病,则联合检测的敏感度为100.0%,特异度为41.7%,阳性预测值为21.7%,阴性预测值为100.0%,准确性为71.4%。 结论DEACMP患者早期动脉血Lac和PCT均明显升高,PCT诊断价值优于Lac,联合检测较单项指标检测对DEACMP发病预测价值更理想。 相似文献
86.
Yoshiyuki Suehara Shinji Kohsaka Takuo Hayashi Keisuke Akaike Aiko Kurisaki-Arakawa Shingo Sato Eisuke Kobayashi Sho Mizuno Toshihide Ueno Takeshi Morii Tomotake Okuma Taisei Kurihara Nobuhiko Hasegawa Kei Sano Keita Sasa Taketo Okubo Youngji Kim Hiroyuki Mano Tsuyoshi Saito 《Clinical orthopaedics and related research》2021,479(4):838
87.
Purpose: Lengthy hospitalization places a burden on patients and healthcare resources. However, the factors affecting the length of hospital stay (LHoS) and length of emergency room stay (LERS) in non-fatal bicycle accidents are currently unclear. We investigated these factors to inform efforts to minimize hospitalization.
Methods: We performed a retrospective analysis of data from non-fatal injured bicyclists admitted to the Emergency and Critical Care Center at Kyoto Medical Center between January 2012 and December 2016. We measured LHoS, LERS, mechanism of injury, head injury prevalence, polytrauma, operations performed, injury severity score (ISS), abbreviated injury scale (AIS) score, maximum AIS score, and trauma and injury severity score probability of survival. We conducted multiple regression analysis to determine predictors of LHoS and LERS.
Results: Within the study period, 82 victims met the inclusion and exclusion criteria and were included. Mean age was (46.0 ± 24.7) years. Overall mean LHoS was (16.8 ± 25.2) days, mean LERS was (10.6 ± 14.7) days, median ISS was 9 (interquartile range (IQR): 3-16), median maximum AIS was 3 (IQR: 1-4), and median trauma and injury severity score probability of survival was 98.0% (IQR: 95.5%-99.6%). Age, maximum AIS, ISS, and prevalence of surgery were significantly greater in long LHoS and LERS group compared with short LHoS and LERS group (p < 0.05). Performance of surgery independently explained LHoS (p = 0.0003) and ISS independently explained LERS (p = 0.0009).
Conclusion: Surgery was associated with long hospital stays and ISS was associated with long emergency room stays. To improve the quality life of the bicyclists, preventive measures for reducing injury severity or avoiding injuries needing operation are required. 相似文献
88.
Jeremy Yuen-Chun Teoh Terry Cheuk-Fung Yip Grace Chung-Yan Lui Vincent Wai-Sun Wong Viola Chi-Ying Chow Tracy Hang-Yee Ho Timothy Chun-Man Li Yee-Kit Tse Peter Ka-Fung Chiu Chi-Fai Ng David Shu-Cheong Hui Henry Lik-Yuen Chan Cheuk-Chun Szeto Grace Lai-Hung Wong 《Journal of the American Society of Nephrology : JASN》2021,32(4):961
BackgroundSevere acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19) are closely related. The effect of AKI on the clinical outcomes of these two conditions is unclear.MethodsThis retrospective, territory-wide cohort study used an electronic public healthcare database in Hong Kong to identify patients with SARS or COVID-19 by diagnosis codes, virologic results, or both. The primary endpoint was a composite of intensive care unit admission, use of invasive mechanical ventilation, and/or death.ResultsWe identified 1670 patients with SARS and 1040 patients with COVID-19 (median ages, 41 versus 35 years, respectively). Among patients with SARS, 26% met the primary endpoint versus 5.3% of those with COVID-19. Diabetes mellitus, abnormal liver function, and AKI were factors significantly associated with the primary endpoint among patients with either SARS or COVID-19. Among patients with SARS, 7.9%, 2.1%, and 3.7% developed stage 1, stage 2, and stage 3 AKI, respectively; among those with COVID-19, 6.6%, 0.4%, and 1.1% developed stage 1, stage 2, and stage 3 AKI, respectively. In both groups, factors significantly associated with AKI included diabetes mellitus and hypertension. Among patients with AKI, those with COVID-19 had a lower rate of major adverse clinical outcomes versus patients with SARS. Renal function recovery usually occurred within 30 days after an initial AKI event.ConclusionsAKI rates were higher among patients with SARS than those with COVID-19. AKI was associated with major adverse clinical outcomes for both diseases. Patients with diabetes mellitus and abnormal liver function were also at risk of developing severe consequences after SARS and COVID-19 infection. 相似文献
89.
Tun Hing Lui 《The Journal of foot and ankle surgery》2021,60(4):850-855
Chronic lateral ankle instability is a prevalent condition, and it is commonly associated with other foot and ankle injuries. Among the associated injuries, peroneal tendon pathologies and anterolateral ankle impingement are frequently encountered. In this report, a case of concomitant chronic lateral ankle instability and dislocation of the peroneal tendons is described. While this combination of injuries is not uncommon, the method of treatment entailed arthroscopic repair of the anterior talofibular ligament and endoscopic repair of the superior peroneal retinaculum, procedures that eliminated the anterior drawer instability that had been present, and the patient remained symptom free after 24 months of follow-up. 相似文献