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排序方式: 共有840条查询结果,搜索用时 15 毫秒
831.
Parents of children with Asperger syndrome or with learning disabilities: family environment and social support 总被引:1,自引:0,他引:1
The study examined the family environment and perceived social support of 33 parents with a child diagnosed with Asperger syndrome and 43 parents with a child with learning disability, which were compared to 45 parents of children without disabilities as a control group. Parents completed the Family Environment Scale and Social Support Scale questionnaires. The comparison revealed significant differences for expressiveness and family system organization and for social support. Parents with an Asperger child perceived their family's expressive feelings as lower and the family organization as higher, and perceived their friendships and other support as lower than the other groups of parent. Parents of the control group reported the highest family support. The study highlighted the need for additional social support for parents with a child with special needs, and accentuated the importance of developing awareness and intervention programs to facilitate parents' coping abilities and their family interactions. 相似文献
832.
Monitoring of chemotherapy-induced cell death in melanoma tumors by N,N'-Didansyl-L-cystine 总被引:1,自引:0,他引:1
Cohen A Ziv I Aloya T Levin G Kidron D Grimberg H Reshef A Shirvan A 《Technology in cancer research & treatment》2007,6(3):221-234
Early assessment of the efficacy of anticancer agents is a highly desirable and an unmet need in clinical oncology. Clinical imaging of cell-death may be useful in addressing this need, as induction of tumor cell-death is the primary mechanism of action of most anticancer drugs. In this study, we examined the performance of N,N'-Didansyl-L-cystine (DDC), a member of the ApoSense family of novel small molecule detectors of cell-death, as a potential tool for monitoring cell-death in cancer models. Detection of cell-death by DDC was examined in fluorescent studies on B16 melanoma cells both in vitro and ex vivo following its in vivo administration. In vitro, DDC manifested selective uptake and accumulation within apoptotic cells that was highly correlated with Annexin-V binding, changes in mitochondrial membrane potential, and caspase activation. Uptake was not ATP-dependent, and was inducible by calcium mobilization. In vivo, DDC selectively targeted cells undergoing cell-death in melanoma tumors, while not binding to viable tumor cells. Chemotherapy caused marked tumor cell-death, evidenced by increased DDC uptake, which occurred before a detectable change in tumor size and was associated with increased animal survival. These data confirm the usefulness of imaging of cell-death by DDC as a tool for early monitoring of tumor response to anti-cancer therapy. 相似文献
833.
Melatonin, the hormone produced nocturnally by the pineal gland, is an endogenous regulator of the sleep-wake cycle. The effects of melatonin on brain activities and their relation to induction of sleepiness were studied in a randomized, double-blind, placebo controlled functional magnetic resonance imaging (fMRI) study. Melatonin, but not placebo, reduced task-related activity in the rostro-medial aspect of the occipital cortex during a visual-search task and in the auditory cortex during a music task. These effects correlated with subjective measurements of fatigue. In addition, melatonin enhanced the activation in the left parahippocampus in an autobiographic memory task. Results demonstrate that melatonin modulates brain activity in a manner resembling actual sleep although subjects are fully awake. Furthermore, the fatigue inducing effect of melatonin on brain activity is essentially different from that of sleep deprivation thus revealing differences between fatigues related to the circadian sleep regulation as opposed to increased homeostatic sleep need. Our findings highlight the role of melatonin in priming sleep-associated brain activation patterns in anticipation of sleep. 相似文献
834.
Tali Mass Amatzia Genin Uri Shavit Mor Grinstein Dan Tchernov 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(6):2527-2531
Worldwide, many marine coastal habitats are facing rapid deterioration due in part to human-driven changes in habitat characteristics, including changes in flow patterns, a factor known to greatly affect primary production in corals, algae, and seagrasses. The effect of flow traditionally is attributed to enhanced influx of nutrients and dissolved inorganic carbon (DIC) across the benthic boundary layer from the water to the organism however, here we report that the organism’s photosynthetic response to changes in the flow is nearly instantaneous, and that neither nutrients nor DIC limits this rapid response. Using microelectrodes, dual-pulse amplitude-modulated fluorometry, particle image velocimetry, and real time mass-spectrometry with the common scleractinian coral Favia veroni, the alga Gracilaria cornea, and the seagrass Halophila stipulacea, we show that this augmented photosynthesis is due to flow-driven enhancement of oxygen efflux from the organism to the water, which increases the affinity of the RuBisCO to CO2. No augmentation of photosynthesis was found in the absence of flow or when flow occurred, but the ambient concentration of oxygen was artificially elevated. We suggest that water motion should be considered a fundamental factor, equivalent to light and nutrients, in determining photosynthesis rates in marine benthic autotrophs. 相似文献
835.
Finkelstein Y Shenkman B Sirota L Vishne TH Dardik R Varon D Linder N 《European journal of pediatrics》2002,161(5):270-274
Platelet function in preterm infants with sepsis was evaluated by measuring their adhesion and aggregation properties using the Cone and Plate(let) Analyser. This may lead to earlier detection of bleeding tendency in septic infants. Platelet function was investigated in 54 preterm infants, of whom 32 had proven neonatal sepsis and 22 were healthy matched controls. Citrated whole blood was subjected to shear stress (1300 s(-1)) for 2 min on tissue culture plates precoated with subendothelial extracellular matrix (ECM). The percentage of ECM surface covered with platelets and the average size of the ECM-bound platelet particles were determined with an image analyser. Assays for von Willebrand factor (vWF) antigen, ristocetin co-factor, and vWF collagen binding activity (CBA) were performed on samples from an additional 47 preterm infants: 38 healthy and 9 septic. Platelets of the preterm infants with sepsis displayed lower adhesion than those of the healthy controls. Mean surface coverage was 16.9+/-8.2% for the septic infants, 15.4+/-7.9% for the septic infants after exclusion of those with coagulase-negative staphylococci sepsis, and 20.8+/-9.6% for the healthy group ( P<0.05). Platelet aggregation, vWF antigen, ristocetin co-factor, and CBA levels were similar between the septic and healthy groups. The most significant factor influencing surface coverage was the presence of sepsis. CONCLUSION: platelet adhesion to extracellular matrix is significantly lower in septic preterm infants than in healthy preterm infants. Intrinsic platelet properties, rather than the concentration or activity of plasma von Willebrand factor, may be responsible for this difference. Surface coverage obtained by the collagen binding activity test under flow conditions, which represents platelet adhesion, may be an earlier, more sensitive indicator of bleeding tendency in neonatal sepsis than decreased platelet count. 相似文献
836.
Oshra Saphier Tali Silberstein Guy Yardeni Jeanine Blumenfeld Israel Zilbermann Ariela Burg 《The journal of maternal-fetal & neonatal medicine》2016,29(17):2865-2869
Objectives: The aim of the study was to investigate whether lycopene from natural sources (tomato extract) is able to protect newborns milk formula, against oxidative damage caused by exposure to hydroxyl radicals, and is there a difference between milk substitutes from various sources.Methods: Four commercial brands of infant milk formula: two of the formulas were dairy milk (A-d and B-d) and two were based on soy bean vegan milk (A-s and B-s), were exposed to ionizing radiation radical (·OH). Lipid peroxidation was determined by measuring malondialdehyde (MDA) using thiobarbituric acid reactive substance test (TBARS).Results: When suspensions containing the four brands of formula were subjected to oxidizing media produced by ionizing radiation (hydroxyl radicals), lipid peroxidation increased linearly as a function of the irradiation dose (R?=?0.99). It was found that lycopene in a concentration of 0.6?mM, reduced the radiation damage only in the soy-based formula; decrease of ~40% of the damage achieved in B-s, and ~20% reduction in the damage caused to A-s, significantly p?<?0.01.Conclusions: Lycopene in dairy milk did not protect against hydroxyl radicals; however, lycopene found to protect against hydroxyl radicals in soy milk. This result suggests different mechanisms of radical production that arises from high iron levels present in the soy milk and involving the high-valent iron peroxo species. 相似文献
837.
Respiratory cryptosporidiosis is recognized as a late-stage complication in persons with AIDS. We report two cases of respiratory cryptosporidiosis in patients with HIV infection. The first patient was a 46-year-old person with chronic diarrhea, a two-month history of low-grade fever, progressive dyspnea and productive cough. The search for acid-fast bacillus, Pneumocystis jirovecii, Toxoplasma gondii and Cryptococcus sp. in sputum was negative on several samples. The modified Ziehl has shown oocysts of Cryptosporidium sp. in induced sputum. The patient's death occurred, due to electrolytes disorders. The second patient was a 45-year-old person hospitalized for chronic fluid diarrhea, complicated with weight loss, dry cough, dyspnea stage II and low-grade fever. The patient was HIV-positive with low CD4 count and pancytopenia. Acid-fast oocysts of Cryptosporidium sp. were observed in stool samples and induced sputum. The patient was treated daily with azithromycin 500 mg resulting of disappearance of gastrointestinal and respiratory disorders. 相似文献
838.
Yuval Bdolah Uriel Elchalal Shira Natanson-Yaron Hadas Yechiam Tali Bdolah-Abram Caryn Greenfield 《Hypertension in pregnancy》2014,33(2):250-259
Objective: To test the hypothesis that the risk of preeclampsia in nulliparous women may be due to an anti-angiogenic state. Methods: Maternal serum samples obtained in the third trimester from nulliparous (n?=?86) and multiparous (n?=?165) singleton uncomplicated pregnancies were analyzed for levels of angiogenic factors – soluble fms like tyrosine kinase 1 (sFlt1) and placental growth factor (PlGF) by enzyme-linked immunosorbent assay (ELISA). Results: For nulliparous and multiparous pregnancies, serum sFlt1 levels were 12?732?±?832 and 10?162?±?666 (p?=?0.020), serum PlGF levels were 215?±?15 and 249?±?14 (p?=?0.093) (all reported as mean SD in pg/ml) and mean ratios of sFlt1/PlGF were 93?±?12 and 62?±?5 (p?=?0.023), respectively. Adjustment for maternal age and fetal birth weight did not alter the results. Conclusions: Nulliparous pregnancies had higher circulating sFlt1 levels and sFlt1/PlGF ratios than multiparous pregnancies, suggesting an association with an angiogenic imbalance. Taken together with the pathogenic role of anti-angiogenic factors in preeclampsia, our data may be one explanation for the epidemiological observation that nulliparity is a risk factor for the development of preeclampsia. 相似文献
839.
Iris Ohel Amalia Levy Tali Silberstein Gershon Holcberg Eyal Sheiner 《The journal of maternal-fetal & neonatal medicine》2013,26(5):305-308
Objective.?The study was designed to investigate obstetric risk factors and pregnancy outcome of patients with pruritic urticarial papules and plaques of pregnancy (PUPPP).Methods.?A population-based study comparing all pregnancies of women with and without PUPPP was conducted. Deliveries occurred during the years 1988–2002 at the Soroka University Medical Center. A multivariable logistic regression model was constructed in order to find independent risk factors associated with PUPPP.Results.?During a 15-year period, 159 197 deliveries took place. PUPPP complicated 42 (0.03%) of all pregnancies. Using a multivariable analysis, the following conditions were significantly associated with PUPPP: multiple pregnancies (odds ratio (OR) = 4.9, 95% confidence interval (CI) 1.7–14.1), hypertensive disorders (OR = 2.2, 95% CI 1.1–4.7), and induction of labor (OR = 7.6, 95% CI 4.0–14.5). Higher rates of 5-minute Apgar scores lower than 7 (OR = 8.0, 95% CI 4.4–14.9) and of cesarean deliveries (OR = 2.9, 95% CI 1.5–5.6) were noted in the PUPPP as compared to the comparison group. While investigating other perinatal outcome parameters such as oligohydramnios, intrauterine growth restriction, meconium-stained amniotic fluid and perinatal mortality, no significant differences were observed between the groups.Conclusion.?Pruritic urticarial papules and plaques of pregnancy is a condition significantly associated with multiple pregnancies, hypertensive disorders, and induction of labor. Perinatal outcome is comparable to pregnancies without PUPPP. 相似文献
840.
Tali Leizer BSc Barry J. Clarris PhD Patricia E. Ash BSc Joseph Van Damme PhD Jeremy Saklatvala MD John A. Hamilton PhD 《Arthritis \u0026amp; Rheumatology》1987,30(5):562-566
Monocyte—macrophage polypeptides (monokines) cause synovial cells to increase the levels of putative mediators of destruction and inflammation. This interaction may account for some of the properties of rheumatoid pannus. We report here that samples of purified human interleukin-1β(IL-1β) and recombinant IL-1β stimulate both the plasminogen activator activity and prostaglandin E2 levels of human synovial fibroblast-like cells. The same holds true for purified pig IL-1 (catabolin) and recombinant murine IL-1. The elevation in plasminogen activator activity was inhibited by indomethacin, and this suggests that endogenous prostanoids are important in the IL-1-mediated stimulation of proteinase activity. 相似文献