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排序方式: 共有6530条查询结果,搜索用时 31 毫秒
1.
Andreas Karatsaidis Olav Schreurs Kristen Helgeland Tony Axéll Karl Schenck 《Journal of oral pathology & medicine》2003,32(5):275-281
BACKGROUND: Common clinical forms of oral lichen planus (OLP) and oral lichenoid reactions (OLR) are erythematous (ERY) or reticular (RET). The purpose of this study was to find histopathological changes that differ between these forms. METHODS: Epithelial thickness, epithelial proliferation rate, apoptosis, and HLA-DR expression were compared among 10 reticular and 12 erythematous lesions, and 11 normal oral mucosa samples (NOM). RESULTS: The epithelium in ERY was thinner than in NOM, whereas RET showed values between ERY and NOM. Cell proliferation increased significantly in ERY as compared with RET and NOM, with no difference between RET and NOM. Relative numbers of epithelial cell nuclei displaying visible chromatin condensation were reduced in ERY form. CONCLUSIONS: The markedly increased cell proliferation in ERY supports the notion that this form displays a higher disease activity as compared to RET. It can therefore be important to study each disease form separately. 相似文献
2.
3.
Sheryl A. Scott Seth Dinowitz Kristen Terhaar Diane Sherlock Maurice A. Campbell Dreania Levine 《The Journal of comparative neurology》1994,350(2):302-310
The goal of the present study was to identify cytochemical markers characteristic of muscle afferents in hatchling chicks. To this end, we stained neurons in the trigeminal mesencephalic nucleus with a variety of markers that label subsets of neurons in avian dorsal root ganglia. We found that trigeminal mesencephalic neurons are surprisingly heterogeneous in their cytochemical make-up, expressing, to varying degrees, substance P, cholecystokinin, carbonic anhydrase, calbindin D-28k, parvalbumin, and S-100β. Calbindin D28k and S-100β appeared to be expressed equally in medial and lateral divisions of the trigeminal mesencephalic nucleus. In contrast, substance P- and cholecystokinin-immunoreactive neurons were more abundant in the medial division, whereas carbonic anhydrase activity and parvalbumin immunoreactivity were stronger in the lateral division. We were unable to detect met-enkephalin, neuropeptide Y, calcitonin gene-related peptide, vasoactive intestinal peptide, somatostatin, γ-aminobutyric acid, or tyrosine hydroxylase in the trigeminal mesencephalic nucleus. Moreover, these neurons did not appear to bind the lectin Dolichos biflorus agglutinin. The heterogeneity of expression of markers among trigeminal mesencephalic nucleus neurons, especially between neurons in the medial and lateral divisions, suggests that these neurons are functionally diverse. 相似文献
4.
Antiviral immune responses modulate the nature of central nervous system (CNS) disease in a murine model of multiple sclerosis 总被引:4,自引:0,他引:4
Summary: In animals and in humans, T-cell therapy can cure advanced disseminated leukemia that would otherwise be fatal. The therapeutic effect of immune T cells is quantitative. As the dose of effector T cells is increased, survival is proportionately increased. Therefore, effective T-cell therapy is predicated on the ability to procure large numbers of immune effector T cells. By using cultured T cells, the number of immune T cells can be increased in vivo substantially above che level achievable by vaccination. The survival of cultured T ceils in vivo is dependent upon both the culture conditions used and the therapeutic regimens employed. Under appropriate conditions, cultured T ceils can proliferate in vivo in response to stimulation by antigen, distribute widely and survive long term to provide effector function and immunologic memory. Given that T cells recognize peptides. the need for immunization with tumor can be circumvented by immunization with peptide. Peptide-specific T cells and the progeny of single T-cell clones can provide the necessary cellular functions to eradicate disseminated murine leukemia. The ability of cloned T cells to similarly provide substantial measurable immunity in humans has been validated in clinical trials. By priming with peptides and by using established culture conditions, T-cell therapy can now be directed against virtually any antigen within the host T-cell repertoire. The major remaining question to be answered is which proteins and which peptides are the most suitable targets for T-cell therapy trials. 相似文献
5.
Kristen H. Kjerulff Barbara Pillar Mary Etta Mills Judy Lanigan 《Journal of medical systems》1992,16(1):7-13
Technology anxiety, defined as a fear of working with medical equipment, was measured via the use of the Technology Response Questionnaire. Nurses (N=414) working on nine types of nursing units at two hospitals participated in the study. Nurses working on psychiatric units were found to be most anxious about working with medical equipment, while nurses working on surgical and adult intensive care units were least anxious. A comparison of the nurses who were highest and lowest on technology anxiety indicated that those who were most anxious about technology were less positive toward computers, felt more stressed by their work, were lower on job satisfaction, less positive toward the physicians they worked with, lower on personality scales of autonomy and adaptability, were less likely to do care planning regularly or to use nursing diagnoses, and tended to be older than less anxious nurses. 相似文献
6.
Arthur J. Matas Raja Kandaswamy Kristen J. Gillingham Lois McHugh Hassan Ibrahim Bertram Kasiske Abhinav Humar 《American journal of transplantation》2005,5(10):2473-2478
Concern persists that prednisone-free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5-year follow-up of a trial of prednisone-free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death-censored graft survival, 92%; acute rejection-free graft survival, 84% and chronic rejection-free graft survival, 87%. The mean serum creatinine level (+/-SD) at 1 year was 1.6 +/- 0.6; at 5 years, 1.7 +/- 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone-free as of April 30, 2005. As compared with historical controls, recipients on prednisone-free maintenance immunosuppression had a significantly lower rate of a number of complications, including cataracts (p < 0.001), posttransplant diabetes mellitus (p < 0.001), avascular necrosis (p = 0.001), and fractures (p = 0.004). We conclude that prednisone-related side effects can be minimized in a protocol incorporating prednisone-free maintenance immunosuppression. Five-year graft outcome remains good. 相似文献
7.
Zusammenfassung In der vorgestellten Arbeit wurden insgesant 15 Ovarialtumoren auf ihren Kathepsin D-Gehalt untersucht. Sowohl bei den benignen
Ver?nderungen wie auch bei den malignen konnte diese Protease nachgewiesen werden. Bei den malignen Tumoren fand sich keinerlei
Korrelation des Kathapsin D zur Exprimierung des Markers Ca 125 und zum ?strogenrezeptorbesatz. 相似文献
8.
Peter Augat Kristen Margevicius Jrg Simon Steffen Wolf Gebhard Suger Lutz Claes 《Journal of orthopaedic research》1998,16(4):475-481
To characterize the site-specific mechanical and histological properties in fracture repair and to relate these properties to the initial mechanical situation, an experimental fracture model was used in the metatarsus of 42 sheep. the mechanical situation of a transverse osteotomy was described by three gap sizes (1,2, or 6 mm) and two amounts of strain (7 or 31 %). An external fixator that allowed a defined axial movement provided control of these settings. Nine weeks following surgery, the healing area was dissected and tensile and compressive properties were measured in subregions of the fracture gap and the periosteal callus. The central, sagittal section was used for quantitative histology. We found the quality of the tissue along the osteotomy line to be most important for regaining mechanical stability. Increasing the size of osteotomy gaps resulted in poorer mechanical and histological qualities, and the repair process was less complete. Interfragmentary strain did not significantly influence the repair process. The smaller strain levels had already stimulated the secondary repair process, and this stimulatory effect could not be further enhanced by increasing the amount of strain. Our finding that large gaps between bone segments were not as well healed as were smaller gaps suggests that it is advantageous to avoid large gaps in fracture treatment. 相似文献
9.
Individual differences in adult human sleep and wakefulness: Leitmotif for a research agenda 总被引:9,自引:0,他引:9
This paper reviews the literature on interindividual variability in human sleep parameters, sleepiness, responses to sleep deprivation, and manifestations of sleep disorders. Variability among individuals in sleep/wake biology and behavior is pervasive. The magnitude of such individual differences is often considerable and comparable to the effect sizes of many experimental and clinical interventions. Evidence is accumulating that certain aspects of sleep/wake-related variability--such as sleep duration, daytime sleepiness, and vulnerability to the effects of sleep loss--involve trait characteristics in healthy populations and among sleep-disordered patients. Establishing the trait-specific nature of variability in sleep/wake parameters is a prerequisite for elucidating the corresponding neurophysiologic and/or genetic mechanisms. At present, it remains largely unknown what underlies or predicts sleep/wake-related traits, what relationships these traits may have to each other, and what functional significance may be associated with specific traits. Scientific studies addressing these issues are warranted, as understanding the basis of trait variability may yield new insights into sleep/wake regulation and sleep pathology. Understanding individual differences in sleep and wakefulness may also have provocative but important implications for health economics and clinical care, as well as for safety, productivity, and general well-being. This paper gives suggestions for a research agenda focusing on individual differences in sleep research and sleep medicine. 相似文献
10.