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Marilena Vered Amos Buchner Dan Dayan Moshe Shteif Adi Laurian 《Journal of oral pathology & medicine》2004,33(2):125-128
A case of an unusual lesion from the maxilla is presented. Macroscopically, the lesion was solid and histologically consisted of 'multiple separate keratocysts' of varying size that infiltrated into the surrounding bone and soft tissues. Panoramic image and CT scans showed a multilocular honeycomb ill-defined radiolucency with infiltration into the maxillary sinus and floor of orbit. This lesion should be differentiated from similar odontogenic lesions, such as keratoameloblastoma and papilliferous keratoameloblastoma. As there was no evidence of follicles, islands of ameloblastoma, or papilliferous structures in the entire specimen, the lesion could not be diagnosed as either a keratoameloblastoma or a papilliferous keratoameloblastoma. The invasive and destructive growth behavior, the histopathological features, and the histochemical pattern of the collagen stroma imply that this solid lesion is a neoplasia. It is suggested that the proper term for this lesion is solid variant of odontogenic keratocyst. 相似文献
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Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
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Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献7.
J. M. Lawson J. Tremble C. Dayan H. Beyan R. D. G. Leslie M. Peakman T. I. M. Tree 《Clinical and experimental immunology》2008,154(3):353-359
Type I diabetes (T1D) is a T cell‐mediated autoimmune disease characterized by loss of tolerance to islet autoantigens, leading to the destruction of insulin‐producing beta cells. Peripheral tolerance to self is maintained in health through several regulatory mechanisms, including a population of CD4+CD25hi naturally occurring regulatory T cells (Tregs), defects in which could contribute to loss of self‐tolerance in patients with T1D. We have reported previously that near to T1D onset, patients demonstrate a reduced level of suppression by CD4+CD25hi Tregs of autologous CD4+CD25‐ responder cells. Here we demonstrate that this defective regulation is also present in subjects with long‐standing T1D (> 3 years duration; P = 0·009). No difference was observed in forkhead box P3 or CD127 expression on CD4+CD25hi T cells in patients with T1D that could account for this loss of suppression. Cross‐over co‐culture assays demonstrate a relative resistance to CD4+CD25hi Treg‐mediated suppression within the CD4+CD25‐ T cells in all patients tested (P = 0·002), while there appears to be heterogeneity in the functional ability of CD4+CD25hi Tregs from patients. In conclusion, this work demonstrates that defective regulation is a feature of T1D regardless of disease duration and that an impaired ability of responder T cells to be suppressed contributes to this defect. 相似文献
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Dayan A Feinberg MS Holbova R Deshet N Scheinowitz M 《Annals of clinical and laboratory science》2005,35(1):73-78
The effect of exercise training prior to acute myocardial infarction (AMI) on left ventricular (LV) remodeling is poorly understood. This study investigated the protective effect of 3 weeks of swimming exercise training prior to AMI on cardiac morphology and function. Male Sprague-Dawley rats (n = 35) were randomly assigned to 3 groups: swimming training (n = 14, 90 min, 5 days/wk, 3 wk), sedentary (n =14), and controls (n = 7, no exercise, no MI). At the end of the training/sedentary period, rats were subjected to AMI (ExMI and SedMI) induced by surgical ligation of the left coronary artery. Thereafter, the rats remained sedentary for a 4-wk recovery period. Trans-thoracic echocardiography was performed in each group at the end of the exercise/sedentary period (pre-AMI), 24 hr after AMI, and following recovery (4 wk after AMI). No differences were observed in LV dimensions and function pre-AMI among the 3 groups; however, LV-end systolic diameter (LVESD) and LV-end systolic area (LVES-area) were significantly lower in the prior trained rats, 24 hr post-AMI with no additional change 4 wk post-AMI, during remodeling. Both LV-shortening fraction (SF%) and fractional area change (FAC%) were higher in the trained animals 4 wk post-AMI (39+/-12% vs 23+/-8%; p 0.002, and 48+/-14% vs. 38+/-9%; p 0.07, respectively). In conclusion, 3 wk of swimming exercise training prior to AMI significantly attenuated LV remodeling and improved LV function, despite no changes in LV dimensions or systolic function at the end of the exercise session. The data suggest that even a short-term training period is sufficient to induce cardiac protection. 相似文献
10.
Influenza B/Beijing/1/87 neuraminidase heads were isolated from virus via trypsin digestion and characterized by PAGE, N-terminal sequencing, electron microscopy, and enzyme activity. The heads were crystallized into two crystal forms; tetragonal plates, like other neuraminidase crystals described before, that diffract to medium resolution (3 A) and a new form consisting of trigonal prisms or needles that diffract to high resolution (at least 2 A). The gene segment coding for neuraminidase was sequenced and compared with the neuraminidase sequence of B/Lee/40. The deduced amino acid sequences for neuraminidase showed only a 7% difference, whereas those for the NB proteins differed by 20%. 相似文献