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21.
22.
BACKGROUND: A study was performed to determine the type and frequency of ocular injuries in patients with major trauma. METHODS: All patients with ocular and adnexal injuries (n = 178) among 1,119 patients admitted with major trauma (Injury Severity Score >15) to the Royal Prince Alfred Hospital from July 1990 to December 1997 were analyzed. RESULTS: Sixteen percent of the major trauma cohort had ocular or orbital trauma. Fifty-five percent of patients with injuries involving the face had ocular or orbital injuries. A range of ocular injuries was seen. Analysis of the major trauma cohort showed that motor vehicle drivers, orbital and base of skull fractures, eyelid lacerations, and superficial eye injuries were strongly associated with vision-threatening injury. CONCLUSION: Patients with major trauma and facial injuries have a high risk of vision-threatening injury. Patients with orbital fractures, base of skull fracture, eyelid lacerations, and superficial eye injuries should be assessed by an ophthalmologist as part of the early management of their trauma to determine whether an ocular injury is present. 相似文献
23.
Tissue factor expression correlates with tumor angiogenesis and invasiveness in human hepatocellular carcinoma. 总被引:23,自引:0,他引:23
Ronnie Tung-Ping Poon Cecilia Pik-Yuk Lau Joanna Wen-Ying Ho Wan-Ching Yu Sheung-Tat Fan John Wong 《Clinical cancer research》2003,9(14):5339-5345
PURPOSE: Recent studies have shown that tissue factor (TF) may be involved in tumor angiogenesis and metastasis. The role of TF in hepatocellular carcinoma (HCC) was unknown. This study evaluated whether TF expression correlates with microvessel density (MVD), vascular endothelial growth factor (VEGF) expression, tumor invasiveness, and prognosis in human HCC. EXPERIMENTAL DESIGN: Tissue samples were obtained from 58 specimens of resected HCC. Immunohistochemical expression of TF was examined, and tumor MVD was evaluated using CD34 as the endothelial marker. TF and VEGF protein levels in the tumor cytosol were quantified by ELISA. Clinicopathologic and follow-up data of patients were prospectively collected. RESULTS: The immunohistochemical expression of TF in the tumors correlated significantly with tumor MVD (P = 0.002). The median cytosolic TF protein level in the tumors was 720 pg/mg total protein (range, 67-2406 pg/mg total protein). A significant positive correlation was found between TF and VEGF levels in the tumor cytosol (r = 0.475, P < 0.001). High tumor cytosolic TF level was associated with venous invasion (P = 0.004), microsatellite nodules (P = 0.024), unencapsulated tumor (P = 0.007), and advanced tumor stage (P = 0.010). A higher than median tumor cytosolic TF level was an independent predictor of poor survival (risk ratio, 1.836; 95% confidence interval 1.130-5.312, P = 0.023). CONCLUSIONS: This study shows that TF is related to tumor angiogenesis and invasiveness in HCC. Evaluation of tumor TF expression may be useful as a prognostic indicator in patients with HCC. 相似文献
24.
Janet Martin Stephen M. Stribbling Grace K. Poon Richard H. J. Begent Mark Napier Surinder K. Sharma C. J. Springer 《Cancer chemotherapy and pharmacology》1997,40(3):189-201
Antibody-directed enzyme prodrug therapy (ADEPT) was administered to ten patients in a phase I clinical trial. The aim was
to measure plasma levels of the prodrug 4-[(2-chloroethyl)(2-mesyloxyethyl) amino] benzoyl-l-glutamic acid (CMDA) and the bifunctional alkylating drug (CJS11) released from it by the action of tumour-localised carboxypeptidase
G2 (CPG2) enzyme. New techniques were developed to extract the prodrug and drug from plasma by solid-phase adsorbtion and
elution and to measure CPG2 activity in plasma and tissue. All extracts were analysed by high-performance liquid chromatography
(HPLC) and liquid chromatography-mass spectrometry (LC-MS). CPG2 activity was found in metastatic tumour biopsies but not
in normal tissue, indicating that localisation had been successful. The clearing agent SB43-gal, given at 46.5 mg/m2, achieved the aim of clearing non-tumour-localised enzyme in the circulation, indicating that conversion of prodrug to drug
could take place only at the site of localised conjugate. Plasma prodrug did not always remain above its required threshold
of 3 μM for the “therapeutic window” of 120 min after dosing, but the presence of residual prodrug after the first administration
of each day indicated that this could be achieved during the remaining four doses over the following 8 h. Despite considerable
inter-patient prodrug plasma concentration variability, the elimination half-life of the prodrug was remarkably reproducible
at 18 ± 8 min. Rapid appearance of the drug in plasma indicated that successful conversion from the prodrug had taken place,
but also undesirable leakback from the site of localisation into the bloodstream. However, drug plasma levels fell rapidly
by at least 50% at between 10 and 60 min with a half-life of 36 ± 14 min. Analysis of the plasma extracts by LC/MS indicated
that this technique might be used to confirm qualitatively the presence of prodrug, drug and their metabolites.
Received: 21 July 1996 / Accepted: 20 January 1997 相似文献
25.
This paper describes a PC-based system for simultaneous monitoring of locomotor and sound activities on small rodents. The displacement and location signals of the animal were first determined across consecutive video-frames, followed by marked data reduction to cater for long-term studies. At the same time, sounds generated by the animal were detected and the sound level was recorded as root-mean-square values at 1 s intervals. Preliminary data showed that such a multi-parametric monitor system could provide comprehensive information on the animal's activity. 相似文献
26.
Ling Liu Bruce Urch Raymond Poon Mieczyslaw Szyszkowicz Mary Speck Diane R. Gold Amanda J. Wheeler James A. Scott Jeffrey R. Brook Peter S. Thorne Frances S. Silverman 《Environmental health perspectives》2015,123(6):534-540
Background
Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers.Objectives
We examined changes of blood and urinary biomarkers following exposures to three particle sizes.Methods
Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences.Results
One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs.Conclusions
Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.Citation
Liu L, Urch B, Poon R, Szyszkowicz M, Speck M, Gold DR, Wheeler AJ, Scott JA, Brook JR, Thorne PS, Silverman FS. 2015. Effects of ambient coarse, fine, and ultrafine particles and their biological constituents on systemic biomarkers: a controlled human exposure study. Environ Health Perspect 123:534–540; http://dx.doi.org/10.1289/ehp.1408387 相似文献27.
Pre-operative grading of intracranial glioma. 总被引:9,自引:0,他引:9
W W Lam K W Chan W L Wong W S Poon C Metreweli 《Acta radiologica (Stockholm, Sweden : 1987)》2001,42(6):548-554
AIM: To compare the accuracy of MR-determined cerebral blood volume (CBV) maps with SPECT imaging with thallium-201 in pre-operative grading of intracranial glioma. MATERIAL AND METHODS: Nineteen patients (7 female and 12 male, mean age 46.8 years) with intracranial gliomas were examined with MR perfusion imaging pre-operatively. Sixteen of these patients were also examined with SPECT imaging with thallium-201. The tumour to contralateral white matter NI (negative integral) and tracer uptake ratios were evaluated. The ratios in high-grade and low-grade tumours were compared. RESULTS: The maximum CBV ratios of grades I and II gliomas (2.958+/-2.217) were significantly lower than the maximum CBV ratio of grades III and IV (9.484+/-4.520), p<0.001. There was no statistical difference when CBV ratios of grades I and II (p=0.381), grades II and III (p=0.229) and grades III and IV (p=0.476) gliomas were compared. Thallium SPECT imaging showed no difference in tumour uptake ratio between low-grade and high-grade gliomas (p=0.299). CONCLUSION: MR-determined NI was useful for pre-operative grading of intracranial gliomas but SPECT thallium-201 imaging was not. 相似文献
28.
Delayed portal vein thrombosis after experimental radiofrequency ablation near the main portal vein 总被引:4,自引:0,他引:4
BACKGROUND: Portal venous blood flow may protect adjacent tumour cells from thermal destruction with radiofrequency ablation (RFA). This study aimed to investigate the local effect of RFA on the main portal vein branch, and the completeness of cellular ablation in its vicinity, with or without a Pringle manoeuvre using a porcine model. METHODS: This was an in vivo study on 23 domestic pigs. RFA using a cooled-tip electrode was performed 5 mm from the left main portal vein branch under ultrasonographic guidance for 12 min with (n = 10) or without (n = 10) a Pringle manoeuvre. Ten pigs were killed 4 h after the procedure to study the early effects of RFA and ten others were killed 1 week later to determine any delayed effect. As a control, sham operations with a Pringle manoeuvre for 12 min were performed on three pigs. The flow velocity changes of portal vein and hepatic artery were measured using Doppler ultrasonography, and the completeness of cellular ablation around the portal vein was assessed qualitatively by histochemical staining and quantitatively by measuring intracellular levels of adenosine 5'-triphosphate (ATP). RESULTS: In the absence of the Pringle manoeuvre, there was no significant change in mean(s.d.) portal vein flow velocity before RFA (20.0(3.5) cm/s) and at 4 h (18.5(2.5) cm/s) (P = 0.210) and 1 week (19.5(2.2) cm/s) (P = 0.500) after the procedure. Gross and histological examination of the portal vein branches showed no damage without the Pringle manoeuvre. In all pigs that underwent RFA with a Pringle manoeuvre, the portal vein was occluded 1 week after the operation; histological examination of the affected portal vein showed severe thermal injury and associated venous thrombosis. The local effect of RFA on the hepatic artery was similar. With intact portal blood flow during RFA, complete ablation of liver tissue around the pedicle was demonstrated by histochemical staining and measurement of the intracellular ATP concentration. CONCLUSION: RFA was safe when applied close to the main portal vein branch without a Pringle manoeuvre, with complete cellular destruction. Use of the Pringle manoeuvre resulted in delayed portal vein and hepatic artery thrombosis and injury to the hepatic artery and bile duct. 相似文献
29.
中国人2型糖尿病合并高甘油三酯血症患者脂蛋白酯酶基因突变及功能分析 总被引:5,自引:0,他引:5
目的 研究中国人2型糖尿病合并高甘油三酯血症患者脂蛋白醒酶(1ipoprotein lipase,LPL)基因突变及对酶功能的影响,从脂代谢途径探讨引发糖尿病的遗传因素。方法 对高甘油三酯及血脂正常的2型糖尿病患者和正常人的LPL基因进行研究。利用PCR—SSCP、PCR—RFLP及DNA测序技术对LPL基因的启动子和10个外显子区域进行突变检测,针对特异位点进行体外定点突变和酶活力表达研究,利用网上工具平台Swiss-PDB Viewer对正常和突变蛋白进行二级结构模拟分析。结果 在177例高甘油三酯2型糖尿病患者中检测到4种错义突变:Ala71Thr、Val181IIe、Glyl88Glu和Glu242Lys,在正常血脂的糖尿病患者和健康人组中没有检出以上突变。这4种突变位于进化上高度保守的氨基酸位点,并分别在高度保守的外显子3、5及6区域。体内和体外酶活力研究表明,这4个突变均引起了酶活力降低甚至失活,其改变程度可以从它们所在序列的保守性、在酶功能结构城中的相对位置、相应的二级结构改变和氨基酸特性获得解释。结论 在受累个体中,LPL突变是引起患者血浆甘油三酯升高的直接原因,是其发展成2型糖尿病的遗传性易感因素。 相似文献
30.
Nancy J. Treat Leonard W. Poon James L. Fozard Samuel J. Popkin 《Experimental aging research》2013,39(4):305-319
Four elements of a successful program of cognitive skill training for the elderly include: (a) the use of mnemonic aids for the memorization of new information; (b) the development of motivational techniques to enhance attention to materials and maintenance of cognitive skills acquired through training; (c) the design of techniques which utilize individual differences in abilities personality, and cognitive style to enhance individual programs of cognitive skill training; and (d) the use of appropriate medical and/or psychiatric care when necessary. 相似文献