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11.
John Nicholas 《Journal of interferon & cytokine research》2005,25(7):373-383
Most herpesviruses of the beta and gamma subfamilies encode homologues of cytokines and chemokine receptor- related G protein-coupled receptors (GPCRs). The roles of these proteins during normal virus replication in the infected host have not been defined in most cases, but the available data and extrapolation from what is known about the properties and functions of their cellular counterparts indicate that they play primary roles in immune evasion or in activating cellular signaling cascades that enhance virus productive replication. Cytokines and chemokine receptors specified by the two human gammaherpesviruses, human herpesvirus 8 (HHV-8) and Epstein-Barr virus (EBV), are the subject of this review. HHV-8 encodes three chemokines, a homologue of interleukin-6, and a CXCR2-related chemokine receptor, while EBV encodes a distinct GPCR and a homologue of interleukin-10. While these viral cytokines and chemokine receptors no doubt contribute to virus biology, their properties indicate that they may also be involved in virus-induced neoplasia. This review discusses the properties, functions, and likely roles of HHV-8 and EBV cytokines and chemokine receptors in relation to both virus biology and virus-associated disease. 相似文献
12.
Beth T McCreary Thomas E Joiner Norman B Schmidt Nicholas S Ialongo 《Journal of clinical child and adolescent psychology》2004,33(2):313-324
This study examined the structure and symptom correlates of perfectionism in a sample of 6th-grade, urban, African American children using the Child and Adolescent Perfectionism Scale (CAPS; Flett, Hewitt, Boucher, Davidson, & Munro, 2000). Confirmatory factor analysis showed inadequate fit of the original subscales. Exploratory factor analysis suggested 3 dimensions of perfectionism: A Socially Prescribed and a Self-Oriented-Critical factor were described as maladaptive, whereas a Self-Oriented-Striving factor was proposed as adaptive. Cross-sectional correlations among the perfectionism dimensions and symptoms of psychopathology fit well with the adaptive versus maladaptive model. In addition, Socially Prescribed Perfectionism showed a robust predictive relation to 7th-grade internalizing symptoms, especially depression, in boys. Results are discussed in the context of the cultural and socioeconomic characteristics of this African American sample and suggestions for future research are provided. 相似文献
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ContextZD4054 is a specific endothelin A (ETA) receptor antagonist being investigated for the treatment of hormone-resistant prostate cancer (HRPC). ZD4054 binds specifically to the ETA receptor, with no detectable activity at the ETB receptor. In preclinical studies, ZD4054 inhibited endothelin (ET-1)-mediated changes in cellular invasiveness in vitro, and inhibited angiogenesis and growth of tumour xenografts in vivo. Consistent with its specific binding profile, ZD4054 inhibited ETA-receptor-mediated antiapoptotic events while allowing ETB-receptor-mediated proapoptotic signalling.Evidence acquisitionThe preclinical and clinical activity of ZD4054 is reviewed.Evidence synthesisIn the clinical setting, stable levels of circulating ET-1 following single ZD4054 doses up to 240 mg demonstrated the absence of ZD4054 activity at the ETB receptor. ZD4054 is cleared principally via the urine, with a terminal elimination half-life of approximately 8–12 hours and with little accumulation after once-daily oral dosing.In a Phase 2 trial, patients with metastatic HRPC who were pain free or mildly symptomatic for pain were randomized to once-daily oral tablets of ZD4054 10 mg (n = 107), or 15 mg (n = 98), or matched placebo (n = 107). ZD4054 was generally well tolerated in this population, with an adverse effect profile consistent with its known pharmacological activity. The most common adverse effects were headache, peripheral oedema and nasal congestion. At the primary analysis there was no statistically significant difference in time to progression between the ZD4054-treated groups and placebo (hazard ratio [HR]: ZD4054 10 mg, 0.88 [80% CI 0.71, 1.09]; ZD4054 15 mg, 0.83 [0.66, 1.03]). However, a promising signal for prolonged overall survival was observed, which was sustained at a subsequent analysis (HR versus placebo: ZD4054 10 mg, 0.55 [80% CI 0.41, 0.73]; ZD4054 15 mg, 0.65 [0.49, 0.86]).ConclusionsThese results support the strategy of targeting the ETA receptor in prostate cancer, and mandate further investigation of ZD4054 in Phase 3 clinical trials. 相似文献
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Vanaporn Wuthiekanun Varunee Desakorn Gumphol Wongsuvan Premjit Amornchai Allen C. Cheng Bina Maharjan Direk Limmathurotsakul Wirongrong Chierakul Nicholas J. White Nicholas P. J. Day Sharon J. Peacock 《Clinical and Vaccine Immunology : CVI》2005,12(4):555-556
An immunofluorescent (IF) method that detects Burkholderia pseudomallei in clinical specimens within 10 min was devised. The results of this rapid method and those of an existing IF method were prospectively compared with the culture results for 776 specimens from patients with suspected melioidosis. The sensitivities of both IF tests were 66%, and the specificities were 99.5 and 99.4%, respectively. 相似文献
16.
Nicholas L. Shortt Gary F. Keenan Andrew Y. Muir Prof. Dr. A. Hamish R. W. Simpson 《Operative Orthopadie und Traumatologie》2006,18(4):364-376
OBJECTIVE: Avoidance of potential iatrogenic nerve injury during insertion of Ilizarov fine wires into areas of high anatomic risk by using a modified nerve stimulation technique. INDICATIONS: Application of the Ilizarov ring fixator to areas of high anatomic hazard, in situations where anatomic topography may be distorted by previous surgery, trauma, or congenital anomalies. CONTRAINDICATIONS: Use of systemic muscle relaxants. Caution in patient with cardiac pacemaker. SURGICAL TECHNIQUE: Preliminary experiments showed that a standard nerve-stimulating device can deliver a negatively charged, monophasic square pulse of current through Ilizarov wires. During the application of an Ilizarov frame to potentially hazardous anatomic regions, providing no systemic muscle relaxants are used, a voltage field sufficient to cause nerves in close proximity to the Ilizarov wire to depolarize is produced. Identification of a distal muscle twitch provoked by the stimulation may indicate a potential for iatrogenic nerve injury. RESULTS: Results show that with the nerve stimulator set at 2.5 mA (pulsed at a frequency of 2 Hz), peripheral nerves are stimulated if they lie within 5 mm of the wires. Should a distal muscle twitch occur, wires should be repositioned so that equivalent stimulation produces no twitch. The technique was used during Ilizarov frame application in ten patients, with only a single occurrence of distal muscle twitches in a lower-leg frame. Following repositioning of the Ilizarov wire in this case, no further twitches were observed, indicating that no Ilizarov wire was inserted close to peripheral nerves. No neurologic impairment was present postoperatively. 相似文献
17.
Toxocariasis: a serological survey of blood donors in the Australian Capital Territory together with observations on the risks of infection 总被引:4,自引:0,他引:4
W L Nicholas A C Stewart J C Walker 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1986,80(2):217-221
The sera from 660 healthy blood donors from Canberra were tested for antibodies to Toxocara canis by the ELISA test. The results were compared with those from patients with suspected or confirmed visceral larva migrans or ocular toxocariasis. Over 7% of Canberra sera showed elevated levels of antibody reacting with T. canis antigen. Sera from patients resident in Australia with other helminth parasites did not cross-react with T. canis antigen in our tests. However, studies of sera collected in several tropical countries with other parasitic infection, show that cross-reactions with other parasites are possible. The use of purified glycoprotein antigen does not alter the possibility of cross-reaction. Observations and experiments show that people in Canberra may be exposed to the infective eggs of T. canis. 相似文献
18.
A. Robert Spitzer Shalom Stahl David Yarnitsky Ernest W. Johnson John R. Wilson R. A. C. Hughes Stefania Morino Giovanni Antonini Kiyotoshi Kaneko Yoji Ohnishi Tetsushi Atsumi Isao Hozumi Tadashi Miyatake Tetsuo Furukawa James P. Knochel Ikuo Mineo Seiichiro Tarui Francis O. Walker Andrew J. Gitter Walter C. Stolov Nicholas J. Capozzoli 《Muscle & nerve》1996,19(4):531-538
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