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排序方式: 共有641条查询结果,搜索用时 15 毫秒
1.
An improved method for determining 89Sr and 90Sr in urine 总被引:1,自引:0,他引:1
A method has been developed for the rapid isolation and quantitation of 89Sr and 90Sr in urine samples. The radiostrontium is concentrated from the bulk urine sample by coprecipitation with calcium phosphate. The precipitate is then wet ashed with nitric acid, and a solution of the resulting residue in 2 M HNO3-0.5 M Al(NO3)3 is passed through an extraction chromatographic column containing a supported crown ether that preferentially retains strontium. Sorbed strontium may then be eluted from the column with either dilute HNO3 or water and counted via liquid scintillation. A new counting scheme that permits quantitation of both 89Sr and 90Sr on the same day the separation is performed is described. 相似文献
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BACKGROUND: Thoracoabdominal aneurysm type IV (TAA IV) represents only a minority of aortic aneurysms, but as it is an entirely abdominally located aneurysm, vascular surgeons are likely to see such aneurysms in their practice. The current surgical management of TAA IV is reviewed. METHODS: A PubMed/Medline-literature search for TAA IV. RESULTS AND CONCLUSIONS: A detailed preoperative evaluation to determine the rupture and operative risk is required. A threshold size of 5.5-6 cm is recommended for elective repair of TAA IV, which then is adjusted for age and other risk factors. Operative simplicity with the clamp and sew approach to obtain a short aortic cross-clamp time seems to have most support in the literature. The necessity of adjunct treatment to prevent visceral and spinal cord ischemia seems to be needed rarely. Uncomplicated repair has a minimal risk of neurological injury and a low risk of renal failure requiring dialysis in patients without preoperative renal dysfunction or renal artery stenosis. The role of endovascular repair of these aneurysms remains to be established. 相似文献
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Krushkal J; Xiong M; Ferrell R; Sing CF; Turner ST; Boerwinkle E 《Human molecular genetics》1998,7(9):1379-1383
Elevated blood pressure is an important risk factor for renal-, cerebro-
and cardiovascular diseases. We used an efficient discordant sib-pair
ascertainment scheme to investigate the impact of the distal end of the
long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing
genes for the alpha1B and beta2 adrenergic receptors and the dopamine
receptor type 1A on variation of systolic blood pressure in young
Caucasians. We measured eight highly polymorphic markers spanning this
positional candidate gene-rich region in 427 individuals from 55
three-generation pedigrees containing 69 discordant sibling pairs, and
calculated multipoint identity by descent (MIBD) probabilities. The results
of genetic linkage and association tests indicate that the region between
markers D5S2093 and D5S462 is significantly linked to one or more
polymorphic genes influencing interindividual variation in systolic blood
pressure levels. Since the alpha1B adrenergic receptor and dopamine
receptor type 1A genes are located close to these markers, these data
suggest that genetic variation in one or both of these G protein-coupled
receptors, which participate in the control of vascular tone, plays an
important role in influencing interindividual variation in systolic blood
pressure levels.
相似文献
6.
Pettersson F Vogt AM Jonsson C Mok BW Shamaei-Tousi A Bergström S Chen Q Wahlgren M 《Infection and immunity》2005,73(11):7736-7746
The occlusion of vessels by packed Plasmodium falciparum-infected (iRBC) and uninfected erythrocytes is a characteristic postmortem finding in the microvasculature of patients with severe malaria. Here we have employed immunocompetent Sprague-Dawley rats to establish sequestration in vivo. Human iRBC cultivated in vitro and purified in a single step over a magnet were labeled with 99mtechnetium, injected into the tail vein of the rat, and monitored dynamically for adhesion in the microvasculature using whole-body imaging or imaging of the lungs subsequent to surgical removal. iRBC of different lines and clones sequester avidly in vivo while uninfected erythrocytes did not. Histological examination revealed that a multiadhesive parasite adhered in the larger microvasculature, inducing extensive intravascular changes while CD36- and chondroitin sulfate A-specific parasites predominantly sequester in capillaries, inducing no or minor pathology. Removal of the adhesive ligand Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), preincubation of the iRBC with sera to PfEMP1 or preincubation with soluble PfEMP1-receptors prior to injection significantly reduced the sequestration. The specificity of iRBC binding to the heterologous murine receptors was confirmed in vitro, using primary rat lung endothelial cells and rat lung cryosections. In offering flow dynamics, nonmanipulated endothelial cells, and an intact immune system, we believe this syngeneic animal model to be an important complement to existing in vitro systems for the screening of vaccines and adjunct therapies aiming at the prevention and treatment of severe malaria. 相似文献
7.
Studies on the specificity of anti-erythrocyte antibodies in the serum of patients with malaria 总被引:12,自引:0,他引:12 下载免费PDF全文
Sera from patients with Plasmodium falciparum, P. vivax or P. ovale malaria were selected according to their high levels of antibodies against human erythrocyte membranes as measured in a microELISA. The specificity of the anti-erythrocyte antibodies in these sera and two normal sera was investigated by means of an immunoblotting technique in combination with SDS-polyacrylamide gel electrophoresis. All the patients' sera as well as the control sera contained antibodies against several erythrocyte polypeptides. As compared with normal sera, most malaria sera showed elevated levels of antibodies against polypeptides of 80K, 70K, 40K and 28K molecular weights. Two sera reacted strongly against a polypeptide with an electrophoretic mobility similar to the alpha subunit of spectrin. One serum showed strong reaction and several other sera, including normal sera, showed weak reaction against a 45K molecular weight polypeptide corresponding to actin. No pervading differences were seen in the pattern of specificities of the anti-erythrocyte ghost antibodies between sera from patients with P. falciparum, P. vivax or P. ovale infections. 相似文献
8.
Absence of antigenic diversity in Pf155, a major parasite antigen in membranes of erythrocytes infected with Plasmodium falciparum. 总被引:8,自引:0,他引:8 下载免费PDF全文
H K Perlmann K Berzins B Whlin R Udomsangpetch W Ruangjirachuporn M Wahlgren P H Perlmann 《Journal of clinical microbiology》1987,25(12):2347-2354
Pf155 is a merozoite-derived polypeptide antigen which the parasite Plasmodium falciparum deposits in the membranes of erythrocytes at invasion. Eleven laboratory strains or clones of P. falciparum and a large number of isolates obtained from patients from different parts of the world were studied for antigenic diversity in Pf155. Immunoglobulin G antibodies from different serum samples from P. falciparum-infected donors were affinity purified on monolayers of glutaraldehyde-fixed and air-dried erythrocytes infected with P. falciparum of different origins and tested in different combinations by immunoblotting, reinvasion inhibition, and a modified immunofluorescence procedure in which the membranes of recently infected erythrocytes were stained. Similar experiments were performed with monoclonal and oligoclonal antibodies specific for different epitopes in the C-terminal region of Pf155. No strain- or isolate-associated antigenic diversity or size variation of Pf155 was detected, indicating that the immunodominant regions of this antigen are highly conserved throughout the world. 相似文献
9.
Pelin Sahlén Rapolas Spalinskas Samina Asad Kunal Das Mahapatra Pontus Höjer Anandashankar Anil Jesper Eisfeldt Ankit Srivastava Pernilla Nikamo Anaya Mukherjee Kyu-Han Kim Otto Bergman Mona Ståhle Enikö Sonkoly Andor Pivarcsi Carl-Fredrik Wahlgren Magnus Nordenskjöld Fulya Taylan Isabel Tapia-Páez 《The Journal of allergy and clinical immunology》2021,147(5):1742-1752
10.
van der Ploeg I Matuseviciene G Fransson J Wahlgren CF Olsson T Scheynius A 《Scandinavian journal of immunology》1999,49(4):447-453
Interleukin (IL)-13 is a cytokine thought to play an important role in IgE-mediated allergic reactions. The aims of the present study were to localize IL-13 mRNA in positive tuberculin reactions and atopic dermatitis lesions using in situ hybridization and to study the possible influence of atopy on the cytokine gene expression in tuberculin reactions. Punch biopsy specimens were taken from tuberculin reactions in 17 nonatopic and 12 atopic (Phadiatop positive), but otherwise healthy, individuals 72h after injection of purified protein derivative, from chronic lichenified lesions and nonlesional skin in six patients with atopic dermatitis and from normal skin in 12 healthy individuals. IL-13-mRNA-producing cells were located mainly in the dermal-cell infiltrates, both in atopic dermatitis lesions and tuberculin reactions. In the atopic dermatitis lesions, IL-13-mRNA expression was found in close apposition to the epidermis. Higher numbers of IL-13-mRNA-producing cells were observed in the dermal-cell infiltrates of chronic lichenified skin lesions of patients with atopic dermatitis (13.3 cells/mm2, range 0.6-42.4 cells/mm2) than in the tuberculin reactions (1.1 cells/mm2, range 0-3.8 cells/mm2) (P<0.01) despite the larger cell infiltrates in the tuberculin reactions. No significant difference in IL-13 or interferon-gamma gene expression in the tuberculin reactions was seen between atopic and nonatopic individuals. 相似文献