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91.
Avani C. Modi Kristen K. Marciel Shalonda K. Slater Dennis Drotar Alexandra L. Quittner 《Children's Health Care》2013,42(1):78-92
Previous research suggests that both parental supervision and adherence decrease in adolescence, as the drive for independence and autonomy emerge naturally during this developmental period. The current study evaluated relationships between patient-reported parental supervision and adherence in 103 preadolescents and adolescents with cystic fibrosis (CF). Activity patterns (medical and nonmedical) were measured using the daily phone diary (DPD) and adherence to nebulized medications was measured electronically. Age was strongly related to amount of supervision, with less supervision provided for older adolescents. Further, preadolescents and adolescents who spent more of their treatment time supervised by parents, particularly mothers, had better adherence. 相似文献
92.
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94.
Nonpalpable breast lesions: recommendations for biopsy based on suspicion of carcinoma at mammography 总被引:12,自引:0,他引:12
Carcinoma was found in 30% (119 of 400) of biopsy specimens obtained for mammographically suspicious but nonpalpable findings. The authors reviewed the mammograms of these 400 cases without knowledge of the biopsy results and placed each examination into one of four groups based on their suspicion for carcinoma: minimal (n = 82), slight (n = 91), moderate (n = 174), and high (n = 53). In 127 cases, mammograms showed either minimally suspicious calcifications (n = 33) or minimally (n = 49) or slightly (n = 45) suspicious masses. A 4.7% (six of 127) rate of carcinoma was found in these groups; five of the six cancers were in situ. Had follow-up mammography been done rather than biopsy for these 127 less suspicious lesions, it is probable that the delay in diagnosis would not have altered overall prognosis. In the remaining 273 patients, the positive predictive value of mammography for carcinoma would have risen from 30% (119 of 400) to 41% (113 of 273). The authors conclude that in the management of suspicious nonpalpable mammographic findings, the rate of carcinoma for lesions at biopsy can approximate 40%. This is almost double the rate of most published series. 相似文献
95.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:6,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
96.
Marsh JC; Will AJ; Hows JM; Sartori P; Darbyshire PJ; Williamson PJ; Oscier DG; Dexter TM; Testa NG 《Blood》1992,79(12):3138-3144
We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse. 相似文献
97.
It has previously been shown that monolayer cultures derived adherent cells (MDAC), apparently consisting of fibroblasts, macrophages, epithelioid cells, and fat cells, can support long-term stem cell proliferation in vitro. In the present study, the hematopoietic support capability of murine MDAC monolayers was confirmed and the cultured cells further characterized with respect to the following properties: esterase I activity, complement (C3) receptors, IgG (Fc) receptors, colony stimulating activity (csa) production, and collagen synthesis. The cultures were also examined immunohistochemically to localize fibronectin, laminin, and collagen synthesis and to identify the collagen subtypes synthesized. MDAC morphology was as described in previous studies, although fat cells were few in number. It was found that MDAC included some cells with esterase I activity and C3 receptors. Fc receptors were not, however, detected, nor did the cultures produce csa, indicating that mononuclear phagocytes were not present. MDAC synthesized collagen types I and III and also fibronectin. Staining for epithelial basement membrane proteins (collagen types IV and V and laminin) was negative. The results indicate that the vast majority of these cultured MDAC were fibroblasts. 相似文献
98.
Detecting diminutive colorectal lesions at colonoscopy: a randomised controlled trial of pan-colonic versus targeted chromoscopy 总被引:10,自引:0,他引:10
BACKGROUND: Diminutive and flat colorectal lesions can be difficult to detect using conventional colonoscopic techniques. Previous data have suggested that pan-chromoscopy may improve detection rates. No randomised control trial has been performed examining detection rates of such lesions while controlling for extubation time and lavage effect. AIM: We conducted a randomised controlled trial of pan-colonic chromoscopic colonoscopy for the detection of diminutive and flat colorectal lesions while controlling for extubation time and lavage effect. METHODS: Consecutive patients attending for routine colonoscopy were randomised to either pan-chromoscopy using 0.5% indigo carmine (IC) or targeted chromoscopy (control group). A minimum diagnostic extubation time was set at eight minutes with controls undergoing a matched volume of saline wash. RESULTS: A total of 260 patients were randomised; 132 controls and 128 to pan-colonic chromoscopy. Extubation times did not differ significantly between the control (median 15 minutes (range 8-41)) and chromoscopy (median 17 minutes (range 8-39)) groups. The volume of IC used in the pan-chromoscopy group (median 68 ml (range 65-90)) and normal saline used in the control group (69 ml (range 60-93)) did not differ significantly. There was a statistically significant difference between the groups regarding the total number of adenomas detected (p<0.05) with significantly more diminutive (<4 mm) adenomas detected in the pan-chromoscopy group (p = 0.03). Pan-chromoscopy diagnosed more diminutive and flat lesions in the right colon compared with controls (p<0.05), with more patients with multiple adenomas (>3) detected using pan-chromoscopy (p<0.01). Hyperplastic lesions were more commonly detected in the pan-chromoscopy group compared with controls (p<0.001). More hyperplastic polyps were detected in the left colon (86% rectosigmoid) using chromoscopy compared with controls. CONCLUSION: Chromoscopy improves the total number of adenomas detected and enhances the detection of diminutive and flat lesions. Importantly, eight diminutive lesions had foci of high grade dysplasia. Chromoscopy may benefit patients, assuming a high risk of colorectal cancer, and help in risk stratification and planning follow up colonoscopy intervals. 相似文献
99.
Ephraim Glassman Larry A. Chinitz Howard A. Levite James Slater Howard Winer 《Catheterization and cardiovascular interventions》1993,29(3):210-216
Left atrial to femoral arterial bypass was evaluated as a means of supporting patients who were considered to be at high risk for the performance of percutaneous transluminal coronary angioplasty. A 20 French drainage catheter was inserted percutaneously into the left atrium via a modified transseptal technique. Blood was withdrawn from the left atrium and returned through a femoral arterial cannula using a roller pump. Thirteen patients were treated in this fashion with excellent circulatory support. Pump flows varied from 1.5 to 3 liters per minute and bypass time ranged from 27 to 106 min (mean 43±17). Aortic mean pressure was well supported during balloon inflation. No significant complications were encountered. Neither an oxygenator nor a perfusionist is required. The ability to obtain direct left ventricular decompression offers a major potential advantage. Further evaluation of this technique for the support of such patients is indicated. © 1993 Wiley-Liss, Inc. 相似文献
100.
Irene Paganini Vivian Y Chang Gabriele L Capone Jeremie Vitte Matteo Benelli Lorenzo Barbetti Roberta Sestini Eva Trevisson Theo JM Hulsebos Marco Giovannini Stanley F Nelson Laura Papi 《European journal of human genetics : EJHG》2015,23(7):963-968
Schwannomatosis is characterized by the development of multiple non-vestibular, non-intradermal schwannomas. Constitutional inactivating variants in two genes, SMARCB1 and, very recently, LZTR1, have been reported. We performed exome sequencing of 13 schwannomatosis patients from 11 families without SMARCB1 deleterious variants. We identified four individuals with heterozygous loss-of-function variants in LZTR1. Sequencing of the germline of 60 additional patients identified 18 additional heterozygous variants in LZTR1. We identified LZTR1 variants in 43% and 30% of familial (three of the seven families) and sporadic patients, respectively. In addition, we tested LZTR1 protein immunostaining in 22 tumors from nine unrelated patients with and without LZTR1 deleterious variants. Tumors from individuals with LZTR1 variants lost the protein expression in at least a subset of tumor cells, consistent with a tumor suppressor mechanism. In conclusion, our study demonstrates that molecular analysis of LZTR1 may contribute to the molecular characterization of schwannomatosis patients, in addition to NF2 mutational analysis and the detection of chromosome 22 losses in tumor tissue. It will be especially useful in differentiating schwannomatosis from mosaic Neurofibromatosis type 2 (NF2). However, the role of LZTR1 in the pathogenesis of schwannomatosis needs further elucidation. 相似文献