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991.
992.
The biological behavior of the different Trypanosoma cruzi strains is still unclear and the importance of exploring the relevance of these differences in natural isolates is of great significance. Herein we describe the biological behavior of four T. cruzi isolates circulating sympatrically in a restricted geographic area in Argentina endemic for Chagas Disease. These isolates were characterized as belonging to the Discrete Typing Units (DTUs) TcI, TcIII, TcV and TcVI as shown by Multilocus Enzyme Electrophoresis and Multilocus Sequence Typing. In order to study the natural behavior of the different isolates and to preserve their natural properties, we developed a vector transmission model that allows their maintenance in the laboratory. The model consisted of serial passages of these parasites between insect vectors and mice. Vector-derived parasite forms were then inoculated in C57BL/6J mice and number of parasite in peripheral blood, serological response and histological damage in acute and chronic phases of the infection were measured. Parasites from DTUs TcI, TcIII and TcVI were detected by direct fresh blood examination, while TcV parasites could only be detected by Polimerase Chain Reaction. No significant difference in the anti-T. cruzi antibody response was found during the chronic phase of infection, except for mice infected with TcV parasites where no antibodies could be detected. Histological sections showed that TcI isolate produced more damage in skeletal muscle while TcVI induced more inflammation in the heart. This work shows differential biological behavior among different parasite isolates obtained from the same cycle of transmission, permitting the opportunity to formulate future hypotheses of clinical and epidemiological importance. 相似文献
993.
Alamo ST Wagner GJ Sunday P Wanyenze RK Ouma J Kamya M Colebunders R Wabwire-Mangen F 《AIDS and behavior》2012,16(2):368-374
Patients who miss clinic appointments make unscheduled visits which compromise the ability to plan for and deliver quality
care. We implemented Electronic Medical Records (EMR) and same day patient tracing to minimize missed appointments in a community-based
HIV clinic in Kampala. Missed, early, on-schedule appointments and waiting times were evaluated before (pre-EMR) and 6 months
after implementation of EMR and patient tracing (post-EMR). Reasons for missed appointments were documented pre and post-EMR.
The mean daily number of missed appointments significantly reduced from 21 pre-EMR to 8 post-EMR. The main reason for missed
appointments was forgetting (37%) but reduced significantly by 30% post-EMR. Loss to follow-up (LTFU) also significantly decreased
from 10.9 to 4.8% The total median waiting time to see providers significantly decreased from 291 to 94 min. Our findings
suggest that EMR and same day patient tracing can significantly reduce missed appointments, and LTFU and improve clinic efficiency. 相似文献
994.
In situ immunologic characterization of cellular constituents in lymph nodes and spleens involved by Hodgkin's disease 总被引:14,自引:0,他引:14
The cellular constituents in lymph nodes and spleens of patients with Hodgkin's disease were studied with a series of monoclonal antibodies directed against human thymocyte, peripheral T-cell, and la antigens. Utilizing both an immunoperoxidase technique on frozen tissue sections and indirect immunofluorescence on cell suspensions, wer found that a majority of lymphocytes were T cells, since they stained with anti-T1 and anti-T3 antibodies, which react with all peripheral T cells. In addition, most of these cells were reactive with anti-T4 antibody, which defines the helper/inducer T-cell population, whereas only a minority of cells stained with anti-T5 and anti-T8 antibodies, which are reactive with suppressor/cytotoxic T cells. Moreover, a large proportion of T cells expressed T10 antigen, which is found on activated T cells. A minority of the T cells also expressed la antigen(s), again suggesting that some of the T cells are activated. In contrast, the Reed-sternberg cells did not react with any of these anti- T-cell antibodies or with anti-IgM antiserum, but displayed strong membrane and cytoplasmic staining with anti-la antibody. Taken together, these findings suggest that Reed-Sternberg cells are not of T- cell lineage but may be derived from antigen-presenting reticulum cells in the thymus-dependent areas of lymphoid tissues; these cells are normally associated with T4+ cells. 相似文献
995.
Long-term culture-initiating cell expansion is dependent on frequent medium exchange combined with stromal and other accessory cell effects 总被引:5,自引:2,他引:5
Despite considerable effort, the expansion of long-term culture- initiating cells (LTC-ICs) in cultures of purified hematopoietic cells has not yet been achieved. In contrast, LTC-IC expansion has been attained in cultures of bone marrow mononuclear cells (MNC) using frequent medium exchange. The use of frequent medium exchange was, therefore, examined in cultures of CD34-enriched cells. In stromal- free, CD34-enriched cell cultures, medium exchange intervals ranging from 2 days to no feeding for 14 days gave similar results. Six different growth factor combinations, reported by other groups to give optimal expansion of CD34-enriched cells, were tested in comparison with the control combination of IL-3/GM-CSF/Epo/SCF. None of the combinations resulted in improved colony-forming unit-granulocyte macrophage (CFU-GM) expansion or LTC-IC maintenance, although two were equivalent. All stromal-free cultures resulted in loss of LTC-IC to half of input. Because of the limited effect of medium exchange and growth factor variations on CD34-enriched cell cultures, the effect of preformed stroma was next examined. Preformed stroma increased cell (3- fold), CFU-GM (5-fold), and LTC-IC (3-fold) output, but only when the medium was exchanged every other day. Under these conditions, the number of LTC-IC was maintained near input level. The lack of LTC-IC expansion in CD34-enriched cell cultures prompted experiments to examine the effect of cell purification. Parallel cultures were performed at CD34+lin- cell purities of 20%, 40%, 70%, and 95%, with each well containing exactly 4,000 CD34+lin- cells in addition to the CD34- accessory cells required to give the desired percentage. Also, MNC from the same source (approximately 2% CD34+lin-) were cultured at a concentration to give 4,000 CD34+lin- cells per well. As CD34+lin- cell purity was decreased from 95% to 2%, the output of cells, CFU-GM, and LTC-IC increased by threefold to fivefold. The loss of culture performance with purification was likely due to the removal of important accessory cells, because the levels of endogenously produced leukemia inhibitory factor and IL-6 were found to decline significantly with increasing CD34+lin- cell purity. In summary, preformed stroma abrogated the decrease in cell and CFU-GM output from cultured CD34- enriched cells and led to LTC-IC maintenance. In contrast, MNC inocula resulting in a growing stromal layer during the culture led to LTC-IC expansion (3.2-fold).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
996.
Tumor-specific aneuploidy not detected in CD19+ B-lymphoid cells from myeloma patients in a multidimensional flow cytometric analysis 总被引:1,自引:0,他引:1
McSweeney PA; Wells DA; Shults KE; Nash RA; Bensinger WI; Buckner CD; Loken MR 《Blood》1996,88(2):622-632
Aneuploidy and lg light chain restriction were used as separate, independent tumor specific markers to study 26 patients with multiple myeloma to determine whether bone marrow B cells, as defined by CD19 expression, are clonally related to myeloma plasma cells. Specimens were characterized using multidimensional flow cytometry to identify the presence of clonality in both the B lymphoid and plasma cell populations using both surface and cytoplasmic staining with antibodies specific for kappa or lambda lg light chain In none of the patients with multiple myeloma were CD19+ cells found to be clonally restricted to kappa or lambda. The monoclonal plasma cells (MPC) were found to be uniformly negative for CD10, CD19, and CD34, while the CD19+ B lymphoid cells present within the samples expressed normal intensities and relationships of these antigens, which allowed them to serve as internal positive controls. Combined analysis of call surface antigen expression and DNA content allowed plasma cell populations to be characterized for aneuploidy without interference from normal bone marrow cells. The MPC, detected on the basis of bright CD38 expression (CD38+2), demonstrated DNA aneuploidy in 65% of cases (DNA index range of 0.9 to 1.3). These aneuploid DNA distributions had typical cell cycle profiles (including G1,S and G2+M) expected of a proliferating population. In all cases, DNA aneuploidy was confined almost entirely to the CD38+2, CD19- malignant plasma cells, while cells expressing CD19 were diploid. These results support the concept that myeloma is a disease process mediated by self-replicating, late compartments of B- cell ontogeny. 相似文献
997.
Fang‐Fang Zhao MrS Xiao‐Ling Lei MrS Wei He MR Yan‐Hong Gu MS Dong‐Wen Li RN MrS 《International journal of nursing practice》2015,21(4):401-409
The aim of the study was to explore the coping strategy and the effects of self‐efficacy of Chinese undergraduate nursing students when they face the stress in clinical practice. Convenience sampling was used to recruit undergraduate nursing students in Mainland China who have practiced 3 months in hospitals in their final college year. Self‐report questionnaires including demographics, Perceived Stress Scale, coping behaviour inventory and Generalized Self‐Efficacy Scale were collected. The results showed that during clinical practice, assignments and workload were the most common stress to students; transference was the most frequently used coping strategy by students. Self‐efficacy not only had a positive main effect in predicting the frequency of use of staying optimistic and problem solving strategies but also moderated the effects of stress from taking care of patients on transference strategy, as well as stress from assignments and workload on problem solving strategy. It is essential to bolster the students' self‐efficacy to reduce stress and adopt positively the coping strategies during clinical practice. 相似文献
998.
Bakyaita N Dorsey G Yeka A Banek K Staedke SG Kamya MR Talisuna A Kironde F Nsobya S Kilian A Reingold A Rosenthal PJ Wabwire-Mangen F 《The American journal of tropical medicine and hygiene》2005,72(5):573-580
The use of combinations of inexpensive drugs for the treatment of malaria in Africa has been proposed as an interim policy while awaiting the widespread availability of more effective regimens. We compared sulfadoxine-pyrimethamine plus chloroquine or amodiaquine in three districts in Uganda. Patients aged 6 months or greater with uncomplicated falciparum malaria were enrolled and randomized to therapy. Safety, tolerability, and efficacy outcomes, adjusted by genotyping, were assessed over 28 days. Of 1,105 patients enrolled, 1,057 (96%) completed follow-up. For children less than 5 years old, the risk of clinical treatment failure adjusted by genotyping at the three sites ranged from 34% to 67% with chloroquine plus sulfadoxine-pyrimethamine and from 13% to 35% with amodiaquine plus sulfadoxine-pyrimethamine (risk differences 21-32%, P < 0.0001 at all sites). Serious adverse events were uncommon with both regimens. The risk of treatment failure with chloroquine plus sulfadoxine-pyrimethamine, the current standard in Uganda, was unacceptably high. Amodiaquine plus sulfadoxine-pyrimethamine was significantly more efficacious; however, existing levels of resistance raises concern about the useful therapeutic life-span of this regimen. 相似文献
999.
Loss of idealism or realistic optimism? A cross‐sectional analysis of dental hygiene students’ and registered dental hygienists’ professional identity perceptions 下载免费PDF全文
1000.
MR Krespi C Acarturk I Akduman-Akin F Sahin Dagli T Dagli 《Vulnerable children and youth studies》2017,12(4):334-338
The present study aimed to assess the acceptability of a 12-week training programme, Youth Disseminating Life Skills Programme whose aims were to help university students acquire knowledge on and to increase sensitivity towards child abuse and neglect by adopting a qualitative methodology. The sample consisted of 13 university students who took part in the Youth Disseminating Life Skills Programme (10 female, 3 male: mean age 22 years; age range: 20–31). With the help of a general interview guide, the focus group meetings were held. Established conventions guided the analysis. Participants recounted feelings about and benefits of the Programme, and ways to improve the Programme. Feelings about the Programme included both positive (e.g. feeling hopeful) and negative feelings (e.g. feeling traumatised). Participants recounted a variety of benefits of the Programme (e.g. correcting some myths about child abuse). Participants proposed some ways whereby the Programme could be improved. Some findings could be interpreted in terms of existing literature/theory. Other findings extended the literature and could be viewed as targets for future child protection programmes. 相似文献