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21.
22.
Murine hematopoietic stem and progenitor cells: I. Enrichment and biologic characterization 总被引:2,自引:5,他引:2
Murine bone marrow cells were fractionated by fluorescence-activated cell sorting into Rh123lo Lin- c-kit+ Ly6A+, Rh123hi Lin-c-kit+ Ly6A+, and Lin- c-kit+ Ly6A- populations within which most, if not all, of the hematopoietic activities of the marrow resided. The Rh123lo Lin- c- kit+Ly6A+ cells, which consist exclusively of small- or medium-sized lymphocyte-like cells, are highly enriched for long-term hematopoietic in vivo repopulating cells. The enrichment factor for these cells from the marrow was estimated as 2,000-fold. The Rh123hi Lin- c-kit+ Ly6A+ cells, although also highly enriched for day-12 spleen colony-forming units, were relatively depleted of long-term in vivo repopulation capacity. Most, if not all Lin- c-kit+ Ly6A- cells were Rb123hi. In contrast to both Rh123lo and Rh123hi Lin- c-kit+ Ly6A+ stem cell populations, the Lin- c-kit+ Ly6A- cells can be stimulated to proliferate in vitro in the presence of single cytokines, which is a characteristic of committed progenitor cells. No marked synergistic interactions between individual cytokines were observed with this cell population. Both Rh123hi Lin- c-kit+ Ly6A+ mature stem cell and Lin- c- kit+ Ly6A- progenitor cell populations displayed in vivo repopulation kinetics resembling those of the putative short-term hematopoietic repopulating cells. 相似文献
23.
GL Marseglia S Savasta A Ravelli TM Gaino GR Burgio 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(9):1086-1088
We report the case of a 9-year-old boy with a spinal cord meningioma whose only manifestations were recurrent episodes of chest pain lasting for 2 years. This case shows that spinal cord meningioma should be considered among the possible causative factors of chronic chest pain in childhood. Chest pain, meningioma, spinal tumors 相似文献
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25.
Background
There is paucity of literature describing complex elbow trauma in the pediatric population. We described a case of an uncommon pediatric elbow injury comprised of lateral condyle fracture associated with posterolateral dislocation of elbow. 相似文献26.
27.
Leila Sabzmakan Mahmood Ghasemi Mohammad Asghari Jafarabadi Tahereh Kamalikhah Mosharafeh Chaleshgar Kordasiabi 《Substance use & misuse》2018,53(9):1511-1518
Background: Tobacco use is a significant predisposing factor to many diseases. Protection motivation theory is a well-suited theory, since fear can motivate individuals to change their unhealthy behaviors. Objective: This study was conducted to examine the associations between the constructs of this theory with intention and tobacco use behavior. Method: The present cross-sectional study was conducted in Noshahr, Iran. The participants were 440 high school boys selected using a stratified random sampling in 2016. A questionnaire about tobacco use based on protection motivation theory was developed and its validity and reliability were assessed. The questionnaire included the demographic information, the constructs of theory, and tobacco use behavior. Structural equation modeling was used to test the associations between the constructs with intention and tobacco use. Results: The variables of perceived vulnerability (β = 0/137, P < 0.001), fear (β = 0/149, P < 0.001), self-efficacy (β = 0/249, P < 0.001), perceived intrinsic reward (β = ?0.285, P < 0.001), threat appraisal (β = ?0.25, P < 0.001), and coping appraisal (β = 0.358, P < 0.001) had direct effect and are significant with intention. Moreover, perceived vulnerability (β = ?0.158, P < 0.001), fear (β = ?0.172, P < 0.001), self-efficacy (β = ?0.288, P < 0.001), perceived intrinsic reward (β = 0.329, P < 0.001), threat appraisal (β = 0.265, P < 0.001), and coping appraisal (β = ?0.379, P < 0.001) affected tobacco use indirectly through intention and were significantly associated with behavior. Also, intention had direct effect and is significant with tobacco use (β = ?1.156, P < 0.001). Conclusions: The protection motivation theory provides a useful framework for investigating factors of tobacco use among male students. Future tobacco prevention interventions should focus on increasing the vulnerability and fear, decreasing intrinsic reward, and improving self-efficacy to reduce tobacco use. 相似文献
28.
Golaleh Asghari Parvin Mirmiran Firoozeh Hosseni-Esfahani Pantea Nazeri Mahya Mehran Fereidoun Azizi 《Journal of health, population, and nutrition》2013,31(1):37-48
The prevalence of dyslipidaemia has been increasing in developing countries that are undergoing nutrition transition. However, the association of diet quality and lipid profile has not been well-understood in these countries. The aim of the current study was to compare the ability of three diet quality indices—the Mediterranean diet scale (MDS), healthy eating index-2005 (HEI-2005), and diet quality index-international (DQI-I) in relation to changes in lipid profile between baseline and 6.7 years of follow-up. Baseline data from two 24-hour dietary recalls provided by 469 adults with mean age of 38.7±12.3 years, who were participants of the Tehran Lipid and Glucose Study, were analyzed to describe dietary intakes. Data on anthropometry, sociodemography, physical activity, and other lifestyle variables were recorded, and a comparison of baseline and follow-up data revealed changes in the concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C). A general linear model was used in assessing changes in lipid profile depending on adherence to diet quality indices at baseline, after adjustment for age, smoking status, waist-circumference, body mass index, physical activity, and energy intake. A significant interaction was observed between scores and sex, and upon stratification, males in the highest quartile score of the HEI-2005 had significantly lower TG changes than those in the lowest quartile, after adjusting for confounders (-8.8 vs 2.9, p=0.038). No association was apparent in females (-0.2 vs 11.2, p=0.297). In addition, a positive association was found between DQI-I and HDL-C (Q1=0.6 vs Q4=-2.0, p=0.044) in males. In both sexes, all these indices were weakly associated with TC while none was associated with LDL-C. It is concluded: adherence to the HEI-2005 recommendations was weakly associated with reduced TG concentration in an urban Iranian adult population. The MDS and DQI-I were not related to change in lipid profile.Key words: Diet quality index-international, Healthy eating index-2005, Lipid profile, Mediterranean diet scale 相似文献
29.
Nadeem Ahmed Aqeel Mahmood Adeel Mahmood S.S. Tahir Asghari Bano Riffat Naseem Malik Seema Hassan Muhammad Ishtiaq 《Journal of ethnopharmacology》2014
Ethnopharmacological relevance
Ethnomedicinal reports are important for the discovery of new crude drugs from reported medicinal plants with high use value. The current study aimed to document the medicinal flora as well as medicinal knowledge of indigenous plants of local communities from Layyah district, Punjab Province, Pakistan.Material and methods
Rapid appraisal approach (RAA), semi-structured interviews, group meetings with herbalists, landowners and local people having awareness about the medicinal action of plants were employed to collect the data. Use values (UV) and frequency of citation (FC) were calculated to check the relative importance of plants.Results and discussions
The current ethnomedicinal study reported 125 medicinal plant species diversified from 106 genus belonging to the 43 different families and Poaceae was the predominant family over others with 16 reported medicinal plants. Wild herbaceous plants were the predominant over other life forms while among plant parts, leaves contributed 32% followed by the stem (27%), fruit and flowers (15%). Allium sativum exhibited the highest use vale (UV) 0.92 while the lowest UV was exhibited by Lasiurus scindicus which was 0.15.Conclusion
Local communities of district Layyah still have a strong faith on herbal medicines for basic healthcare needs. Indigenous plants having high UV and FC should be subjected to the detailed phytochemical investigations to explore new natural drugs. 相似文献30.
Golaleh?Asghari Emad?Yuzbashian Sahar?Shahemi Zahra?Gaeini Parvin?MirmiranEmail author Fereidoun?Azizi 《European journal of nutrition》2018,57(7):2377-2385