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111.
A clinical study comparing digital radiography and near‐infrared transillumination in caries detection 下载免费PDF全文
112.
James TF Lai John DC Dereix Ravi P Ganepola Peter G Nightingale Kiera A Markey Paul N Aveyard Alexandra J Sinclair 《The journal of headache and pain》2014,15(1):10
Background
Medication-overuse headache (MOH) is caused by the regular use of medications to treat headache. There has been a lack of research into awareness of MOH. We distributed an electronic survey to undergraduate students and their contacts via social networking sites. Analgesic use, awareness of MOH, perceived change in behaviour following educational intervention about the risks of MOH and preferred terminology for MOH was evaluated.Findings
485 respondents completed the questionnaire (41% having received healthcare training). 77% were unaware of the possibility of MOH resulting from regular analgesic use for headache. Following education about MOH, 80% stated they would reduce analgesic consumption or seek medical advice. 83% indicated that over the counter analgesia should carry a warning of MOH. The preferred terminology for MOH was painkiller-induced headache.Conclusions
This study highlights the lack of awareness of MOH. Improved education about MOH and informative packaging of analgesics, highlighting the risks in preferred lay terminology (i.e. painkiller-induced headache), may reduce this iatrogenic morbidity and warrants further evaluation. 相似文献113.
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Although the morphologist continues to describe cholestasis on the basis of precipitated bile seen on light microscopic sections of the liver or dilated canaliculi with loss of microvilli seen by electron microscopy, the physiologist can distinguish clearly between hyperbilirubinemia and cholestasis. Both bilirubin and bile acids are specifically removed from sinusoidal plasma by the normal hepatocyte and appear in bile in high concentration. Bilirubin conjugation and excretion appear to be governed by hepatocellular mechanisms that are, for the most part, separate from the conjugation and excretion of bile acids. Disturbances in bilirubin transport are recognized by hyperbilirubinemia which represents a number of clinical syndromes that can be classified by the nature of the block in the transport system. Serum bile acids appear to remain normal in hyperbilirubinemic syndromes. By contrast, cholestatic syndromes are characterized by marked bile acidemia with normal to slightly elevated bilirubin levels. Severe cholestasis, because of the marked reduction in bile flow, can however, engender jaundice. Further exploration of these excretory pathways will provide interesting new insights on the numerous cholestatic and hyperbilirubinemic syndromes that occur in nature. 相似文献
115.
Human acute leukemia cell line with the t(4;11) chromosomal rearrangement exhibits B lineage and monocytic characteristics 总被引:18,自引:8,他引:18
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia. 相似文献
116.
Acute leukemia associated with the t(4;11) chromosome rearrangement: ultrastructural and immunologic characteristics 总被引:7,自引:1,他引:7
Parkin JL; Arthur DC; Abramson CS; McKenna RW; Kersey JH; Heideman RL; Brunning RD 《Blood》1982,60(6):1321-1331
The acute leukemia associated with the t(4;11) chromosome rearrangement is characterized by relatively consistent clinical features: occurrence primarily in young individuals, hyperleukocytosis, and poor response to therapy. This study describes the morphological, ultrastructural, and immunologic characteristics of the leukemic cells from ten patients with this type of leukemia. The morphological features of the leukemic blasts vary from lymphoid-appearing to monocytic. Ultrastructurally and cytochemically, some of the lymphoid-appearing blasts possess features of myeloid origin. The immunologic phenotype is characteristically E- SIg- CALLA- BA-1- BA-2+ HLA-DR+ and TdT+. These findings suggest that the t(4;11)-associated acute leukemia represents a proliferation of an early myeloid progenitor cell. 相似文献
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119.
Transient leukemoid proliferation of the cytogenetically unbalanced +21 cell line of a constitutional mosaic boy 总被引:1,自引:0,他引:1
A newborn without any signs of Down's syndrome was found to have an acute proliferation that remitted without drug therapy. Chromosomal analysis of blood, bone marrow, and skin cells revealed that the child was a constitutional mosaic with normal cells and a low number of cells in which one no. 21 chromosome was replaced by a probably isochromosome for the no. 21 long arm: 46,XY/46,XY,i(21q). The abnormal cell line of the mosaic appeared to be selectively involved in this proliferation. 相似文献
120.
Effect of recombinant granulocyte colony-stimulating factor on neutrophil kinetics in normal young and elderly humans 总被引:15,自引:3,他引:15
Recombinant granulocyte colony-stimulating factor (G-CSF) was administered to healthy young (n = 32) and elderly (n = 19) volunteers (0 microgram/d, 30 microgram/d, or 300 microgram/d) to determine its effect on neutrophil production, blood kinetics, and tissue migration. Measurements included blood counts (daily), marrow neutrophil pool sizes and neutrophil tissue migration (baseline and day 5), blood kinetics (day 6), and marrow transit time while on drug (days 6 to 14). G-CSF markedly expanded the marrow neutrophil mitotic pool and shortened the transit time of the postmitotic pool (control, mean = 6.4 days; 300 microgram/d, mean = 2.9 d). G-CSF increased neutrophil production without significantly altering blood neutrophil half-life or margination. Compared to control, neutrophil accumulation in skin chambers decreased by about 50% in the 300 microgram/d group in both young and elderly subjects. G-CSF induced neutrophilia by stimulating proliferation of marrow neutrophil precursors and accelerating neutrophil entry into the blood. Decreased neutrophil inflammatory responses measured with the skin chamber technique may be because of the relative immaturity of the circulating cells or to alterations in neutrophil phenotype induced by G-CSF. 相似文献