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991.
B Avron A Chayen T Stolarsky R Schauer G Reuter D Mirelman 《Molecular and biochemical parasitology》1987,25(3):257-266
A novel sialoglycoprotein with an apparent molecular mass of approximately 250 kDa was detected on the surface of cysts of Entamoeba invadens. Sialic acid was identified in this glycoprotein by gas chromatography after methanolysis; N-acetyl- and N-glycolyl neuraminic acid were identified by thin layer chromatography in hydrolysates of partially purified preparations of the 250 kDa glycoprotein as well as in whole cysts. The sialoglycoprotein is stage-specific and could be detected by binding of wheat germ agglutinin and a specific monoclonal antibody (JAM3) only to precysts and mature cysts but not to trophozoites. A 250 kDa protein could be metabolically labeled with [35S]methionine. This, together with the absence of such a glycoprotein in the encystation medium, suggests that the 250 kDa sialoglycoprotein is not an adsorbed serum glycoprotein. Indirect evidence suggests that the parasite may utilize serum components as a source for sialic acid. 相似文献
992.
Allicin inhibits SDF-1alpha-induced T cell interactions with fibronectin and endothelial cells by down-regulating cytoskeleton rearrangement, Pyk-2 phosphorylation and VLA-4 expression 总被引:2,自引:0,他引:2
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Sela U Ganor S Hecht I Brill A Miron T Rabinkov A Wilchek M Mirelman D Lider O Hershkoviz R 《Immunology》2004,111(4):391-399
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases. 相似文献
993.
Johannes W. G. Jacobs MD PhD Agnes van der Heide MD Johannes J. Rasker MD PhD Johannes W. J. Bijlsma MD PhD 《Patient education and counseling》1993,20(2-3):121-132
Chronic arthritis may have great impact on the patient but also on his or her family, relatives and friends. The assessment of the consequences of chronic arthritis and the effect of therapy not only in terms of physical, but also psychological and social dimensions deserves more attention. Functional ability and health status can be measured using a questionnaire or ‘instrument’, high-lighting important aspects not quantified with more traditional measurements. In this paper, arguments to apply such instruments more frequently are given. Health status instruments can be used not only to assess beneficial but also deleterious (side-)effects of therapeutic interventions. The properties are summarized of the most frequently used instruments assessing functional ability and health status. Many of these instruments have been evaluated sufficiently for validity and reliability; their sensitivity to detect change seems to be satisfactory. Therefore it is advisable to choose an internationally accepted, frequently used instrument, reflecting the area of interest. 相似文献
994.
995.
Ichiya Yamazaki MD PhD Norihisa Karube MD PhD Tamitaro Soma MD Yasuharu Noishiki MD PhD Yukio Ichikawa MD PhD 《Journal of artificial organs》2005,8(1):67-70
The aim of this study was to test the safety and efficacy of fragmented autologous adipose tissue (FAT) grafts for revascularization in aortoiliac occlusive disease. Twenty-seven patients with atherosclerotic aortoiliac occlusive disease underwent surgical treatment using FAT grafts. A piece of adipose connective tissue was obtained from the operative wound, cut into small pieces, and pressed into the wall of a fabric vascular prosthesis. Cumulative primary patency rates were 92% at 1 year, 92% at 3 years, and 86% at 6 years. Cumulative secondary patency rates were 96%, 96%, and 90% for the same intervals. In this clinical study, the FAT grafts demonstrated good long-term patency rates and no particular problems. This is the first clinical report of long-term outcomes using FAT grafts for aortofemoral or aortoiliac bypasses. FAT grafts are thus safe for revascularization in aortoiliac occlusive disease. 相似文献
996.
997.
Benjamin B. Gelman MD PhD Dwayne A. Wolf MD PhD Juan Pablo Olano MD Lannette C. Linthicum MD 《Human pathology》1996,27(12):1282-1287
The Texas Department of Criminal Justice (TDCJ) houses many subjects with acquired immunodeficiency syndrome (AIDS) who receive medical care in a comprehensive AIDS treatment center. In this case-control autopsy survey, we compared pathological outcomes of TDCJ inmates treated at the center (n = 155) with nonincarcerated patients who died during the same period (n = 155). Using multiple regression analysis and a proportional hazards model, survival time in the prisoners was equivalent to that in the controls. With few exceptions, the prevalences of opportunistic viral, fungal, protozoal, and bacterial infections contributing to mortality were equivalent between groups. Mycobacterium tuberculosis was isolated more frequently in the inmates, and M avium intracellulare was isolated less frequently (P < .0001). The inmates had a higher prevalence of bacterial infection of the central nervous system (CNS) (9.1% v 1.4%; P < .006); half of all CNS bacterial infections were caused by M tuberculosis. Inmates had significantly lower prevalences of vacuolar myelopathy (P < .006) and severe wasting disease (P < .0009). We conclude that survival of prison inmates with AIDS treated in a comprehensive AIDS treatment center was equivalent to that of nonincarcerated subjects with AIDS. Prevalences of certain complications of AIDS differed in the inmates, showing that the prison environment influenced some of the underlying causes of AIDS morbidity and mortality. 相似文献
998.
We have developed a Joint Photographic Experts Group (JPEG) compatible image compression scheme tailored to the compression of digitized mammographic images. This includes a preprocessing step that segments the tissue area from the background, replaces the background pixels with a constant value, and applies a noise-removal filter to the tissue area. The process was tested by performing a just-noticeable difference (JND) study to determine the relationship between compression ratio and a reader's ability to discriminate between compressed and noncompressed versions of digitized mammograms. We found that at compression ratios of 15∶1 and below, image-processing experts are unable to detect a difference, whereas at ratios of 60∶1 and above they can identify the compressed image nearly 100% of the time. The performance of less specialized viewers was significantly lower because these viewers seemed to have difficulty in differentiating between artifact and real information at the lower and middle compression ratios. This preliminary study suggests that digitized mammograms are very amenable to compression by techniques compatible with the JPEG standard. However, this study was not designed to address the efficacy of image compression process for mammography, but is a necessary first step in optimizing the compression in anticipation of more elaborate reader performance (ROC) studies. 相似文献
999.
Core biopsies of the bone marrow are indispensable in the evaluation of fever of unknown etiology in human immunodeficiency virus-positive patients. We report two patients in whom visceral leishmaniasis was diagnosed based on the typical morphology, staining characteristics, and ultrastructure of the organisms. 相似文献
1000.
The role of the complement system in innate immunity 总被引:4,自引:0,他引:4
Complement is a major component of innate immune system involved in defending against all the foreign pathogens through complement
fragments that participate in opsonization, chemotaxis, and activation of leukocytes and through cytolysis by C5b-9 membrane
attack complex. Bacterias and viruses have adapted in various ways to escape the complement activation, and they take advantage
of the complement system by using the host complement receptors to infect various cells. Complement activation also participates
in clearance of apoptotic cells and immune, complexes. Moreover at sublytic dose, C5b-9 was shown to promote cell survival.
Recently it was also recognized that complement plays a key role in adaptive immunity by modulating and modifying the T cell
responses. All these data suggest that complement activation constitutes a critical link between the innate and acquired immune
responses. 相似文献