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201.
Expression of CD80 and CD86 on Peripheral Blood T Lymphocytes in Patients with Systemic Lupus Erythematosus 总被引:8,自引:0,他引:8
Abe K Takasaki Y Ushiyama C Asakawa J Fukazawa T Seki M Hirashima M Ogaki M Hashimoto H 《Journal of clinical immunology》1999,19(1):58-66
CD80 and CD86 were detected in high amounts on circulating T cells in the peripheral blood of some patients with systemic lupus erythematosus (SLE), using flow cytometry and monoclonal antibodies. Patients with other connective tissue diseases did not have a high percentage of T cells expressing CD80 or CD86 in their peripheral blood. CD80 was expressed mainly on CD4 T cells, whereas CD86 was expressed on CD8 T cells, and these two populations were associated with paticular clinical features. These two molecules were expressed on different T-cell populations and might have different roles in the generation and regulation of immune responses. Since high expression of CD86 on T cells was detected much earlier than the appearance of clinical features and a high titer of anti-DNA antibody, it may be a useful parameter for predicting the flare of SLE. 相似文献
202.
Hintsanen M Elovainio M Puttonen S Kivimaki M Koskinen T Raitakari OT Keltikangas-Jarvinen L 《International journal of behavioral medicine》2007,14(4):202-212
Background: Work stress indicated by effort—reward imbalance is hypothesized to cause autonomic arousal, which, if prolonged or frequent, could contribute to cardiovascular pathology. However, only limited empirical evidence on this mechanism is available. Purpose: This study examined associations between effort-reward imbalance, heart rate (HR), and heart rate variability (HRV). Method: The participants were 457 women and 406 men (mean age 32.3 years) derived from the population-based Young Finns Study. Effort—reward imbalance was defined as the ratio between effort and reward, higher efforts compared to rewards indicating greater imbalance. Results: In age-adjusted regression models, higher effort-reward imbalance was associated with lower HRV, and lower reward was associated with higher HR among women. These associations were not attenuated after additional adjustments for demographic characteristics and coronary risk factors. No significant associations of effort—reward imbalance or its components with HR and HRV were found in men. Conclusion: Our finding of lower HRV and higher HR in young healthy women with high effort—reward imbalance and low rewards provides evidence of a potential mechanism that may link effort-reward imbalance to the development of coronary heart disease (CHD) in women. 相似文献
203.
Post-neonatal hospitalization and health care costs among IVF children: a 7-year follow-up study 总被引:1,自引:0,他引:1
Koivurova S Hartikainen AL Gissler M Hemminki E Järvelin MR 《Human reproduction (Oxford, England)》2007,22(8):2136-2141
BACKGROUND: The objective of this study was to evaluate whether the post-neonatal hospitalization and resulting health care costs are increased among in vitro fertilization (IVF) children up to 7 years of age. METHODS: We conducted a population-based cohort study with linkage to a national hospital discharge register including 303 IVF children, born from 1990 to 1995, and 567 control children (1:2) randomly chosen from the Finnish Medical Birth Register and matched for sex, year of birth, area of residence, parity, maternal age and socioeconomic status. The cost calculations were stratified for singleton (n = 152 vs. n = 285) and twin (n = 103 vs. n = 103) status. Main outcome measures were hospitalizations and societal health care costs. RESULTS: The full-sample and singleton analyses showed that IVF children were significantly more frequently admitted to hospital (mean 1.76 vs. 1.07, P < 0.0001; 1.61 vs. 1.07, P = 0.0004, respectively) and spent significantly more days in the hospital (mean 4.31 vs. 2.61, P < 0.0001; 3.47 vs. 2.56, P = 0.0014, respectively) than control children. No differences were detected between IVF and control twins. The costs of post-neonatal hospital care per child were 2.6-fold for IVF singletons, but 0.7-fold for IVF twins when compared with controls. Cost estimation showed 2.6-fold costs for total IVF population in comparison to general population based controls. CONCLUSIONS: The incidence of multiple births increases the utilization of post-neonatal health care services and costs among IVF children in comparison to naturally conceived children. Increased hospitalization and costs were also seen among IVF singletons. 相似文献
204.
During prolonged viewing of ambiguous stimuli, such as Necker cubes, sudden perceptual reversals occur from one perceptual interpretation to another. The role of attention in such reversals is not clear. We tested whether perceptual reversals depend on attentional resources by manipulating perceptual load and recording event‐related potentials (ERPs) during intermittent presentation of Necker stimuli. The results did not reveal any influence for perceptual load on the frequency of reversals. The ERPs showed that perceptual load influenced electrophysiological activity over parieto‐central areas in the P1 time window (110–140 ms), but load did not modify the early enhancements of positivity (30–140 ms), which correlated with perceptual reversals at occipito‐temporal sites. We conclude that disambiguation of ambiguous figures is based on early mechanisms that can work efficiently with only a minimal amount of attentional resources. 相似文献
205.
BACKGROUND: This prospective case series was conducted to describe the safety and efficacy of orthokeratology with the Emerald Contact Lens for Overnight Orthokeratology (Oprifocon A; Euclid Systems Corporation, Herndon, Virginia) among young myopes. METHODS: Twenty subjects (ages 10 to 16) were enrolled in the 6-month pilot study. Subjects were fit empirically with overnight orthokeratology lenses and evaluated at 1 day, 1 week, 1 month, 2 months, 3 months, and 6 months. RESULTS: Sixteen subjects completed the study. The mean baseline spherical equivalent refraction (SER) was -2.06 diopters (D) (+/-0.75). The mean SER at 6 months was -0.16 D (+/-0.38). The mean baseline uncorrected acuity was 0.78 (+/-0.28) logarithmic minimum angle of resolution (logMAR) equivalent (20/100 Snellen). The mean logMAR equivalent at 6 months was -0.03 +/- 0.12 (<20/20 Snellen). On average, 40% of eyes showed some type of corneal staining between the 1-week and 6-month visits. No serious adverse events occurred during the study. CONCLUSIONS: In contrast to previously published studies that reported maximum results at 2 weeks, subjects reached maximum reduction in myopia at the 1-week visit and, on average, obtained a 92.2% reduction in spherical equivalent refractive error at 6 months. This pilot study lends to a growing body of evidence that short-term correction of mild to moderate myopia with overnight orthokeratology is safe and efficacious in children and adolescents. 相似文献
206.
Mika Pulkkinen Jere Pikkarainen Thomas Wirth Tommy Tarvainen Vesa Haapa-Aho Harri Korhonen Jukka Sepp?l? Kristiina J?rvinen 《European journal of pharmaceutics and biopharmaceutics》2008,70(1):66-74
Despite recent advances in cancer therapy, many malignant tumors still lack effective treatment and the prognosis is very poor. Paclitaxel is a potential anticancer drug, but its use is limited by the facts that paclitaxel is a P-gp substrate and its aqueous solubility is poor. In this study, three-step tumor targeting of paclitaxel using biotinylated PLA-PEG nanoparticles and avidin-biotin technology was evaluated in vitro as a way of enhancing delivery of paclitaxel. Paclitaxel was incorporated both in biotinylated (BP) and non-biotinylated (LP) PEG-PLA nanoparticles by the interfacial deposition method. Small (mean size approximately 110nm), spherical and slightly negatively charged (-10mV) BP and LP nanoparticles achieving over 90% paclitaxel incorporation were obtained. The successful biotinylation of nanoparticles was confirmed in a novel streptavidin assay. BP nanoparticles were targeted in vitro to brain tumor (glioma) cells (BT4C) by three-step avidin-biotin technology using transferrin as the targeting ligand. The three-step targeting procedure increased the anti-tumoral activity of paclitaxel when compared to the commercial paclitaxel formulation Taxol((R)) and non-targeted BP and LP nanoparticles. These results indicate that the efficacy of paclitaxel against tumor cells can be increased by this three-step targeting method. 相似文献
207.
208.
Hitoshi Yoshimitsu Makiko Nishida Fumio Hashimoto Mika Tanaka Yusuke Sakata Masafumi Okawa Toshihiro Nohara 《Journal of natural medicines》2007,61(3):334-338
One new chromone and six known flavonol glycosides were isolated from the stems and leaves of Delphinium hybridum cv. “Belladonna Casablanca” (Ranunculaceae). The new chromone glycoside was elucidated as 2-methyl-chromone-5,7-diol 7-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (1). The six known flavonol glycosides were designated as compounds 2–5, being kaempferol-type glycosides, and compounds 6 and 7, being quercetin-type glycosides. The structures of these glycosides were determined by two-dimensional nuclear magnetic
resonance (2D NMR) spectroscopic analysis and chemical evidence. 相似文献
209.
Okuno T Sugiyama T Tominaga M Kojima S Ikeda T 《Japanese journal of ophthalmology》2002,46(2):170-176
PURPOSE: To determine the effect of caffeine on microcirculation in the human ocular fundus. METHODS: The microcirculation in the ocular fundus of 10 healthy volunteers (10 eyes) was studied using a laser speckle tissue circulation analyzer. Caffeine or placebo (100 mg) was administered orally in a double-masked manner. Square blur rate (SBR), a quantitative index of blood flow velocity, was measured in a temporal site of the optic nerve head (ONH) free of surface vessels and in a middle site of the choroid-retina between the ONH and macula. Intraocular pressure (IOP), blood pressure (BP), pulse rate (PR), and central critical fusion frequency (CFF) were also measured. These parameters were measured before and for 2 hours after administration. The area under curve (AUC) of SBR was calculated for each area. Ocular perfusion pressure (OPP) was also calculated from BP and IOP. RESULTS: The time-course of change in SBR value showed much individual difference. Caffeine decreased the AUC of SBR in the ONH (P =.0218) as well as in the choroid-retina (P =.0469) significantly. IOP, mean BP, PR, OPP, and central CFF did not change significantly. CONCLUSIONS: These results suggest that caffeine may increase blood vessel resistance and decrease blood flow in the human ONH and choroid-retina. 相似文献
210.
Katoh M Sakurai K Fujimoto Y 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》2002,122(10):831-839
The diabetogenic action of alloxan is thought to be initiated by generation of reactive oxygen species (ROS). Ascorbate can be an antioxidant in a predominantly aqueous environment, such as plasma and extracellular fluids. We have investigated the generation of ROS in the interaction of alloxan with ascorbate. Rapid oxygen consumption was observed in the reactin system of alloxan with ascorbate. The oxygen consumption was suppressed by superoxide dismutase and catalase, suggesting that superoxide and hydrogen peroxide could be generated in the reaction system. In addition, the generation of alloxan radical, an electron reductance of alloxan, and ascorbate free radical (AFR), an electron oxidant of ascorbate, was observed using electron spin resonance (ESR). Under anaerobic conditions, the ESR signal intensity of alloxan radical was significantly increased in comparison with that under aerobic conditions, whereas the intensity of AFR was significantly decreased. These results suggest that alloxan radical and AFR were generated in the reaction system of alloxan with ascorbate, and that the alloxan radical but not AFR reacted with molecular oxygen, resulting in the generation of ROS. 相似文献