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排序方式: 共有644条查询结果,搜索用时 15 毫秒
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Testicular schistosomiasis caused by Schistosoma mansoni is very rare and more so when associated with primary infertility. A 40 years old man from the Jos Plateau, North Central Nigeria presented with primary infertility after ten years of marriage. Sperm count revealed oligospermia and he also complained of inability to sustain erection. Testicular biopsy revealed several ova of Schistosoma mansoni in the connective tissue of the testes. Cases of infertility in endemic areas especially when there is no supply of potable water should raise suspicion of schistosomiasis among other pathologies and possible hormonal disturbances when the testes are involved. 相似文献
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This study reports the quality of life in long-term survivors of oral cancer treated by primary surgery. Two hundred and twenty patients were treated at the Regional Maxillofacial Unit between the years 1987 and 1992, of which 48 were alive and disease free in July 1997. Thirty-eight patients self-completed the following questionnaires: University of Washington Quality of Life Scale (UW-QOL), the European Organisation for Research and Treatment of Cancer (EORTC) core QOQ-C30 (v2) and the EORTC Head and Neck (H&N35). Results for this group were compared with the one year findings of a similar prospective cohort treated in 1995. Long-term survivors tended to report a good or excellent quality of life. Quality of life deficits in the long-term survivors were similar to those at one year. However, a larger longitudinal study is required to test this relationship more rigorously. The similarity of domain scores suggests that quality of life evaluation at one year is a useful marker of long-term outcome. 相似文献
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Adam EM Eltorai Jack Haglin Sudheesha Perera Bielinsky A Brea Roy Ruttiman Dioscaris R Garcia Christopher T Born Alan H Daniels 《World journal of orthopedics》2016,7(6):361-369
Infections can hinder orthopedic implant function and retention.Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion.Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems,material science,immunology,and polymer chemistry are in development and early clinical use.This review outlines orthopedic implant antimicrobial technology,its current applications and supporting evidence,and clinically promising future directions. 相似文献
68.
Uncoordinated expression of fibrinogen compared with thrombospondin and von Willebrand factor in maturing human megakaryocytes 总被引:7,自引:1,他引:7
Cramer EM; Debili N; Martin JF; Gladwin AM; Breton-Gorius J; Harrison P; Savidge GF; Vainchenker W 《Blood》1989,73(5):1123-1129
The localization of three known alpha-granule proteins, thrombospondin (TSP), von Willebrand factor (vWF), and fibrinogen (Fg) has been studied in human megakaryocytes (MK) by immunofluorescence and immunoelectron microscopy. For this study, highly purified populations of MK were prepared from human bone marrow either by counterflow centrifugal elutriation or by cell culture from normal subjects and from two patients with megakaryoblastic leukemia. In normal bone marrow immature MK, TSP, and vWF were observed in the Golgi-associated vesicles and in small immature alpha-granules; in mature MK, they were found in the matrix of the mature large alpha-granules. Surprisingly, Fg was detected neither in the Golgi area, nor in the small precursors of alpha-granules; it was only found in the mature alpha-granules but this labeling was generally weaker than in blood platelets. In order to confirm these differences between the expression of Fg and vWF or TSP additional studies were performed on cultured maturing MK: immunofluorescent and ultrastructural immunogold labeling confirmed that vWF appeared early in the maturation while the same immature MK were negative for Fg. In the late maturation stage, the three proteins were detected in the alpha-granules. In order to know whether Fg was lately synthesized or endocytosed from the outside medium, normal MK were grown in the presence of either normal or afibrinogenemic plasma, and normal serum. Fg was detected only in the alpha-granules of MK grown in normal plasma. Similar results were observed with malignant MK, whose maturation was independent of the culture conditions. In conclusion, this study brings immunocytochemical evidence that vWF and TSP are synthesized by immature MK, whereas Fg appears later in the MK alpha-granules and its expression is dependent of the presence of an exogenous Fg source. 相似文献
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Extended long-term culture reveals a highly quiescent and primitive human hematopoietic progenitor population 总被引:5,自引:17,他引:5
Long-term culture-initiating cells (LTC-IC) are hematopoietic progenitors able to generate colony-forming unit-cells (CFU) after 5 to 8 weeks (35 to 60 days) of culture on bone marrow (BM) stroma and represent the most primitive progenitors currently detectable in vitro. We have recently reported that long-term cultures initiated with CD34+CD38- cells from BM or cord blood are able to continue generating CFU for at least 100 days, ie, beyond the standard LTC-IC period. In this report, single-cell cultures from cord blood and retroviral marking of cord blood and BM were used to study whether the subpopulation of CD34+CD38- cells able to generate CFU beyond 60 days ("extended long-term culture-initiating cells" or ELTC-IC) are functionally distinct from LTC-IC in terms of timing of initial clonal proliferation and generative capacity. All cord blood LTC-IC formed clones of greater than 50 cells by day 30. In contrast, cord blood ELTC- IC proliferated later in culture, 50% forming clones after day 30. Although efficient retroviral marking of LTC-IC was seen (25% to 45%), marking of ELTC-IC was inefficient (< 1%), consistent with a more quiescent progenitor population. There was a positive correlation between time of clonal proliferation and generative capacity. ELTC-IC generated threefold to fourfold more progeny than did LTC-IC (P < .002). These studies show that there is a functional hierarchy of progenitors in long-term culture which correlates with their level of quiescence. By extending the LTC-IC assay, a more primitive progenitor may be studied that may be functionally closer to the human long-term repopulation stem cell in vivo. 相似文献