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排序方式: 共有1094条查询结果,搜索用时 15 毫秒
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Ian H. de Boer Charles E. Alpers Evren U. Azeloglu Ulysses G.J. Balis Jonathan M. Barasch Laura Barisoni Kristina N. Blank Andrew S. Bomback Keith Brown Pierre C. Dagher Ashveena L. Dighe Michael T. Eadon Tarek M. El-Achkar Joseph P. Gaut Nir Hacohen Yongqun He Jeffrey B. Hodgin Sanjay Jain Sandy Alfano 《Kidney international》2021,99(3):498-510
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C B Hu E Y Lee J E Hewitt J U Baenziger J Z Mu K DeSchryver-Kecskemeti D H Alpers 《Gastroenterology》1991,101(6):1477-1487
Because specific uptake of the asialoglycoprotein haptocorrin has been reported in suckling distal intestine, evidence of the asialoglycoprotein receptor in rat ileum was sought. On Western blot, two different polyclonal antisera against purified rat holoreceptor recognized only proteins of the size of the minor receptor components (51 and 55 kilodaltons) in both suckling and adult rat intestine. Messenger RNA encoding the minor component (RHL-2/3) was detected in total RNA extracted from rat ileum. Calcium-specific binding of porcine or rat haptocorrin-[57Co]cobalamin complexes was detected in the brush border membranes of distal suckling rat and porcine small intestine. This binding was almost completely blocked by another asialoglycoprotein, asialofetuin. The pH optimum for binding was 6-9, with a Ka of 0.25 nmol/L and a capacity of 4.6 fmol/mg protein. These properties, with the exception of the low capacity, are all consistent with those of the intact receptor on hepatocytes. The intestinal receptor was localized not to the basolateral membrane, as in the liver, but to the apical brush border, as suggested by the binding data. Furthermore, immunoperoxidase stains of paraffin-embedded tissue detected strong binding to the brush border and apical phagolysosome of mid and distal suckling rat intestine. These data show that, contrary to expectations, the minor components of the asialoglycoprotein receptor are functional and expressed in the apical membrane of the suckling intestine. The abundance of the protein by Western blot suggests possible roles for it in the neonatal gut other than haptocorrin binding. 相似文献
16.
Small area variation in prevalence of an S-antigen serotype of Plasmodium falciparum in villages of Madang, Papua New Guinea 总被引:2,自引:0,他引:2
K P Forsyth R F Anders J A Cattani M P Alpers 《The American journal of tropical medicine and hygiene》1989,40(4):344-350
Cross-sectional and longitudinal village-based studies of the transmission dynamics of an S-antigen serotype of the asexual erythrocyte stages of Plasmodium falciparum have been carried out in Madang, Papua New Guinea (PNG). Sera collected from village residents were screened for circulating S-antigen of the FC27 serotype by enzyme-linked immunosorbent assay (ELISA). The prevalence of the FC27 S-antigen was found to vary between villages at a given point in time, as well as within a village over time. Residents of villages 2-5 km apart were infected with P. falciparum of different S-antigen serotypes. This study documents the periodic nature of transmission of a sub-population of P. falciparum defined by the FC27 S-antigen. The variation in a small area in the prevalence of this serotype of P. falciparum in Madang illustrates the complexities of malaria transmission which must be considered in the design of malaria vaccine trials. 相似文献
17.
The human serum antibody response to Plasmodium falciparum infection in Papua New Guinea has been studied by electrophoretic analysis of immunoprecipitated biosynthetically-labelled malaria proteins from three different isolates maintained in long-term in vitro culture. Differences in protein antigenic composition in different lines have been described and simplified by examination of antigens recognized only by hyperimmune serum. An in vitro assay has been used to screen various human sera containing antimalarial antibody for their ability to inhibit parasite growth and the immunoprecipitation profiles of non-inhibitory sera have been compared with those of a hyperimmune serum pool. In the discussion, emphasis is placed on the value of immunoprecipitation analyses using clinically-defined sera with known in vitro function in the identification of antigens which may be responsible for the induction of host-protective immunity. 相似文献
18.
[Purpose] The purpose of this study was to investigate the use of smartphones by
university students in selected areas, their musculoskeletal symptoms, and the associated
hazard ratio. [Subjects and Methods] This involved the completion of a self-administered
questionnaire by dental hygiene students in Seoul, Gyeonggido, and Gyeongsangbukdo. The
292 completed copies of the questionnaire were then analyzed. [Results] The most painful
body regions after the use of smartphones were found to be the shoulders and neck. In the
musculoskeletal system, back pain was found to have a positive correlation with the size
of the smartphone’s liquid crystal display (LCD) screen, and pain in legs and feet were
found to have a negative correlation with the length of time that the smartphone was used.
As a result, it was revealed that the use of a smartphone was correlated with
musculoskeletal symptoms. [Conclusion] Therefore, in today’s environment, where the use of
smartphones is on the rise, it is necessary to improve the ways that they are used and to
develop a preventive program to alleviate the symptoms of musculoskeletal damage.Key words: Smartphone, Musculoskeletal symptoms, Prevent 相似文献
19.
DH Mallon M Kostalas FJ MacPherson A Parmar A Drysdale E Chisholm 《Annals of the Royal College of Surgeons of England》2013,95(4):258-262
Introduction
Fine needle aspiration (FNA) is a safe and quick method of diagnosing superficial lumps, which aids preoperative planning. However, FNA of the parotid gland has not gained the widespread acceptance noted in other head and neck lumps. The aim of this study was to determine the ability of FNA of the parotid gland to differentiate benign and malignant disease, and to determine the impact on surgical outcome.Methods
A retrospective analysis of 201 consecutive parotid operations with preoperative FNA in a large district hospital in the UK was performed. The diagnostic characteristics were calculated for benign and malignant disease, and the impact on surgical procedure was determined.Results
In identifying benign disease, FNA has a sensitivity of 85% and a specificity of 76%. In detecting malignant disease, FNA has a sensitivity and specificity of 52% and 92% respectively. A false positive on FNA was associated with a higher incidence of neck dissection.Conclusions
FNA is a useful diagnostic test. However, owing to low sensitivity, it is necessary to interpret it in the context of all other clinical information. 相似文献20.
Gazitt Y; Tian E; Barlogie B; Reading CL; Vesole DH; Jagannath S; Schnell J; Hoffman R; Tricot G 《Blood》1996,87(2):805-811
Peripheral blood stem cells (PBSCs) mobilized with high-dose chemotherapy and hematopoietic growth factors are now widely used to support myeloablative therapy of multiple myeloma and effect complete remissions in up to 50% of patients with apparent extension of event- free and overall survival. Because tumor cells are present not only in bone marrow, but also in virtually all PBSC harvests, it is conceivable that autografted myeloma cells contribute to relapse after autotransplants. In this study, the kinetics of mobilization of normal hematopoietic stem cells were compared with those of myeloma cells present in PBSC harvests of 12 patients after high-dose cyclophosphamide and granulocyte-macrophage colony-stimulating factor administration. CD34+ and CD34+Lin-Thy+ stem cell contents were measured by multiparameter flow cytometry, and myeloma cells were quantitated by immunostaining for the relevant Ig light chain and by a quantitative polymerase chain reaction for the myeloma-specific CDRIII sequence. Results indicated marked heterogeneity in the percentages of mobilized stem cells among different patients (0.1% to 22.2% for CD34+ cells and 0.1% to 7.5% for CD34+Lin-Thy+ cells, respectively). The highest proportions of hematopoietic progenitor cells were observed early during apheresis, with 9 of 12 patients mobilizing adequate amounts of CD34+ cells for 2 autotransplants (> 4 x 10(6)/kg) within the first 2 days, whereas peak levels (percent and absolute numbers) of myeloma cells were present on days 5 and 6 (0.5% to 22.0%). During the last days of collection, mobilized tumor cells exhibited more frequently high labeling index values (1% to 10%; median, 4.4%) and an immature phenotype (CD19+). The differential mobilization observed between normal hematopoietic stem cells and myeloma cells can be exploited to reduce tumor cell contamination in PBSC harvests. 相似文献