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Initial attachment of leukocytes to the vessel wall at sites of inflammation is supported by a family of carbohydrate-binding adhesion molecules called the selectins. Selectin ligands include sialyl-Lewis x (sLex, Neu5Ac alpha 2-3Gal beta 1-4[Fuc alpha 1-3]GlcNAc--) and related structures. We report here that defined heparin oligosaccharides interact with the selectins. Heparin chains containing four or more monosaccharide residues inhibited the function of L- and P-selectin, but not E-selectin, in vitro. In a competition enzyme-linked immunosorbent assay measuring inhibition of solution-phase selectin-Ig fusion proteins (selectin-Ig) binding to immobilized bovine serum albumin-sLex neoglycoprotein, a heparin-derived tetrasaccharide mixture inhibited 50% of L- and P-selectin-Ig binding (IC50) at 200 +/- 40 mumol/L and 850 +/- 110 mumol/L, respectively. A single hexasulfated tetrasaccharide (delta UA2S alpha 1-4GlcNS6S alpha 1-4IdoA2S alpha 1- 4GlcNS6S) was particularly active against L- and P-selectin-Ig (IC50 = 46 +/- 5 mumol/L and 341 +/- 24 mumol/L). By comparison, the tetrasaccharide sLex was not inhibitory at concentrations up to 1 mmol/L. In cell adhesion assays, heparin tetrasaccharides reduced binding of neutrophils to COS cells expressing P-selectin but not to COS cells expressing E-selectin. They also blocked colon cancer cell adhesion to L- and P-selectin but not E-selectin. In a model of acute inflammation, intravenously administered heparin tetrasaccharides diminished influx of neutrophils into the peritoneal cavities of thioglycollate-treated mice. We conclude that heparin oligosaccharides, including non-anticoagulant tetrasaccharides, are effective L- and P- selectin inhibitors in vitro and have anti-inflammatory activity in vivo. 相似文献
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ClinicalstudyofintegratedtraditionalandwesternmedicineinhepatolenticulardegenerationRENMingShan,ZHANGBo,YANGRenMin,HANYong... 相似文献
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Spondylometaphyseal dysplasia, corner fracture type: a heritable condition associated with coxa vara
Langer LO Jr; Brill PW; Ozonoff MB; Pauli RM; Wilson WG; Alford BA; Pavlov H; Drake DG 《Radiology》1990,175(3):761-766
The authors present the radiographic features of a previously incompletely delineated bone dysplasia, which they call spondylometaphyseal dysplasia, corner fracture type. This is a dominant heritable condition associated with short stature and developmental coxa vara. The progressive hip deformity usually causes significant disability requiring surgical correction. Developmental coxa vara, simulated corner fractures of long tubular bones, and vertebral body abnormalities result in a diagnostic constellation. Knowledge of these distinctive radiologic features allows accurate diagnosis, which in turn should lead to appropriate genetic counseling and possibly to earlier, more efficacious surgical treatment of the coxa vara. 相似文献
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The Kheda project experience has shown that bio-environmentalcontrol of malaria is feasible, cost effective and ecologicallysound. It clearly brings out the need to consider health issuesat the planning stage of all developments. Bio-environmentalcontrol of malaria is suggested as the first line of attackfor the control of mosquitoes, malaria and other mosquito-bornediseases. Insecticides may be reserved for short-term use. Thiswill enable judicious and selective use of insecticides in solelyepidemic situations. The growing problem of resistance to insecticidesin mosquitoes as well as environmental pollution, can then besolved on a long term basis. 相似文献
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Ann Wilson RGN RM DipN RCNT RNT BA MPhil Nurse Tutor Richard Startup MA LLB PhD Senior Lecturer 《Journal of advanced nursing》1991,16(12):1478-1486
A comparative study was conducted of the professional socialization process of student nurses in three nurse education centres in South Wales. Patterns and problem areas can be identified of relevance to issues in role theory and with practical implications for the more effective implementation of Project 2000. Three cohorts of students were interviewed using a semi-structured interview schedule whilst in the introductory block and at the end of the first year. The teaching and ward staff directly involved in the socialization process were also interviewed so that their views could be compared with those of the students. There were differences between the types of ward in the opportunities they offered for role modelling. It was doubtful whether the three categories of students, teaching staff and ward staff were all employing a single conception of 'the good nurse'. The student has to find her own pathway through the divergent and often conflicting values and philosophies of the teaching staff and those in authority on the wards. It is recommended that a more unified approach be adopted to reduce the conflict which learners experience. In accordance with Project 2000, the teaching staff should act as practitioners and thereby be perceived as a professional role model with clinical credibility. 相似文献
108.
Helena E. Lindgren RNM MSc Ingegerd M. Hildingsson RNM PhD Kyllike Christensson RNM PhD Ingela J. Rådestad RNM RM PhD 《分娩》2008,35(1):9-15
ABSTRACT: Background: Planning a home birth does not necessarily mean that the birth will take place successfully at home. The object of this study was to describe reasons and risk factors for transfer to hospital during or shortly after a planned home birth. Methods: A nationwide study including all women who had given birth at home in Sweden between January 1, 1992, and July 31, 2005. A total of 735 women had given birth to 1,038 children. One questionnaire for each planned home birth was sent to the women. Of the 1,038 questionnaires, 1,025 were returned. Reasons for transfer and obstetric, socioeconomic, and care‐related risk factors for being transferred were measured using logistic regression. Results: Women were transferred in 12.5 percent of the planned home births. Transfers were more common among primiparas compared with multiparas (relative risk [RR] 2.5; 95% CI 1.8–3.5). Failure to progress and unavailability of the chosen midwife at the onset of labor were the reasons for 46 and 14 percent of transfers, respectively. For primiparas, the risk was four times greater if a midwife other than the one who carried out the prenatal checkups assisted at the birth (RR 4.4; 95% CI 2.1–9.5). A pregnancy exceeding 42 weeks increased the risk of transfer for both primiparas (RR 3.0; 95% CI 1.1–9.4) and multiparas (RR 3.4; 95% CI 1.3–9.0). Conclusions: The most common reasons for transfer to hospital during or shortly after delivery were failure to progress followed by the midwife’s unavailability at the onset of labor. Primiparas whose midwife for checkups during pregnancy was different from the one who assisted at the home birth were at increased risk of being transferred. (BIRTH 35:1 March 2008) 相似文献
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