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排序方式: 共有10000条查询结果,搜索用时 22 毫秒
61.
Ellen J Schlette L Jeffrey Medeiros Andre Goy Raymond Lai George Z Rassidakis 《Journal of clinical oncology》2004,22(9):1682-1688
PURPOSE: Survivin, a member of the inhibitor of apoptosis (IAP) family, is not detected in normal adult tissues but is overexpressed in various cancers, including some types of lymphoma. The frequency and prognostic significance of survivin expression in anaplastic large-cell lymphoma (ALCL) is unknown. Materials and METHODS: We assessed for survivin expression in 62 ALCL tumors (30 anaplastic lymphoma kinase [ALK]-positive and 32 ALK-negative) obtained before doxorubicin-based chemotherapy. Given that survivin is a target of the STAT3 signaling pathway and STAT3 is activated in ALCL, survivin expression was also correlated with STAT3 activation. RESULTS: Survivin was expressed in 34 tumors (55%) and did not correlate with ALK. A significant association between survivin expression and STAT3 activation was observed (P =.007, Fisher's exact test). For the ALK-positive group, the 5-year failure-free survival (FFS) was 34% for patients with survivin-positive ALCL compared with 100% for patients with survivin-negative ALCL (P =.009, log-rank test). For the ALK-negative group, the 5-year FFS was 46% for patients with survivin-positive tumors compared with 89% for patients with survivin-negative tumors (P =.03, log-rank test). Overall survival was similarly worse for patients with survivin-positive tumors in both the ALK-positive and ALK-negative groups. Furthermore, multivariate analysis confirmed the independent prognostic value of survivin expression, along with age older than 60 years and Ann Arbor stage III or IV. CONCLUSION: Survivin is expressed in approximately half of ALCL tumors and independently predicts unfavorable clinical outcome. Modulation of survivin expression or function may provide a novel target for experimental therapy in patients with ALCL. 相似文献
62.
George A Kounis Miltiadis K Tsilimbaris George D Kymionis Harilaos S Ginis Ioannis G Pallikaris 《Optometry and vision science》2007,84(10):962-968
PURPOSE: To describe a new software tool for the detailed presentation of corneal topography measurements variability by means of color-coded maps. METHODS: Software was developed in Visual Basic to analyze and process a series of 10 consecutive measurements obtained by a topographic system on calibration spheres, and individuals with emmetropic, low, high, and irregular astigmatic corneas. Corneal surface was segmented into 1200 segments and the coefficient of variance of each segment's keratometric dioptric power was used as the measure of variability. The results were presented graphically in color-coded maps (Variability Maps). Two topographic systems, the TechnoMed C-Scan and the TOMEY Topographic Modeling System (TMS-2N), were examined to demonstrate our method. RESULTS: Graphic representation of coefficient of variance offered a detailed representation of examination variability both in calibration surfaces and human corneas. It was easy to recognize an increase in variability, as the irregularity of examination surfaces increased. In individuals with high and irregular astigmatism, a variability pattern correlated with the pattern of corneal topography: steeper corneal areas possessed higher variability values compared with flatter areas of the same cornea. Numerical data permitted direct comparisons and statistical analysis. CONCLUSIONS: We propose a method that permits a detailed evaluation of the variability of corneal topography measurements. The representation of the results both graphically and quantitatively improves interpretability and facilitates a spatial correlation of variability maps with original topography maps. Given the popularity of topography based custom refractive ablations of the cornea, it is possible that variability maps may assist clinicians in the evaluation of corneal topography maps of patients with very irregular corneas, before custom ablation procedures. 相似文献
63.
George Wolf DPhil 《Nutrition reviews》2007,65(8):385-388
Retinol-binding protein (RBP) is the transport protein that carries retinol in the circulation from the liver to its target tissues. The existence of a cell-surface receptor on the target cells, which mediates the uptake of retinol from RBP, has been known since 1975. Recently, it was identified as an integral transmem-brane protein named STRA6 that is inducible by retinoic acid in certain cancer cells. The receptor was found to be highly specific for RBP, with high affinity, and to be localized in all tissues known to require retinol for their function, particularly the pigment epithelium of the eye. 相似文献
64.
Premenstrual symptoms in black and white community samples 总被引:1,自引:0,他引:1
A L Stout T A Grady J F Steege D G Blazer L K George M L Melville 《The American journal of psychiatry》1986,143(11):1436-1439
Premenstrual syndrome specialty clinics are reported to be almost exclusively attended by white women. This racial discrepancy has raised the question of whether there is a lower prevalence or severity of symptoms during the premenstruum among black women. The authors evaluated selected premenstrual symptoms in a representative community-based sample and found no difference in the prevalence or severity of premenstrual symptoms reported by black and white women, except for a higher prevalence of food cravings among blacks. Exploration of broader sociocultural factors may explain the observed racial difference in seeking help for premenstrual complaints. 相似文献
65.
The purpose of this study was to examine the effects of object self-stimulation on the task-interrupting self-stimulatory behavior and prevocational work responses of a 13-year-old autistic boy. Using a multiple-baseline design across three diferent prevocational tasks, a systematic manipulation of object self-stimulation was associated with increases in correct rates and decreases in task-interrupting self-stimulatory behaviors. An analysis of these data indicates that self-stimulatory behavior may be shaped to facilitate performance proficiencies. Social validation information suggests that favorable generalized responding had occurred. On the basis of findings from this study, future research needs are discussed. 相似文献
66.
67.
Peter B. Arnold Chris A. Campbell George Rodeheaver Wyndell Merritt Raymond F. Morgan David B. Drake 《Hand (New York, N.Y.)》2009,4(3):302-307
The purpose of this study was to demonstrate that perivascularly applied botulinum toxin-A (BTX) increases the diameter of
treated blood vessels in a rat femoral vessel exposure model. Six adult Sprague–Dawley rats were used and bilateral femoral
artery and vein exposures were performed. Five units of BTX were applied to the experimental side and an equal volume of sterile
saline was applied to the control side. Digital images of the vessels were obtained at the following time points: pretreatment,
immediately posttreatment, and postoperative days (POD) 1, 14, and 28. Vessel diameters were equivalent at baseline and immediately
following application of BTX and saline. The BTX artery was significantly larger than the control artery on POD 1 and 14.
The BTX treated artery was significantly larger than all other vessels on POD 14 (p < 0.05) as well as all prior time points (p < 0.01). Direct perivascular application of BTX increases the diameter of rat femoral vessels as early as POD 1. The affect
is most robust on POD 14 where the artery was significantly larger than all other vessels at all time points. It is likely
that the increased diameter of blood vessels results in an increased blood flow across the area of dilation. Such an increase
in flow may serve to improve end-organ perfusion in microvascular procedures. 相似文献
68.
George K Kouvidis Mark B Sommers Peter V Giannoudis Pavlos G Katonis Michael Bottlang 《Journal of orthopaedic surgery and research》2009,4(1):16-9
Background
Lag screw cut-out failure following fixation of unstable intertrochanteric fractures in osteoporotic bone remains an unsolved challenge. This study tested if resistance to cut-out failure can be improved by using a dual lag screw implant in place of a single lag screw implant. Migration behavior and cut-out resistance of a single and a dual lag screw implant were comparatively evaluated in surrogate specimens using an established laboratory model of hip screw cut-out failure. 相似文献69.
Legionnaire's disease was first identified and described in January 1977. Even today, it is often regarded as an unusual or exotic disease, when in fact it is a very common form of community and nosocomial acquired pneumonia. The major roles of the acute care nurse, including patient health education; psychosocial needs of the patient; and strategies for disease prevention and control, are discussed. 相似文献
70.