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51.
Victoria L Woo Tawfiqul Bhuiya Robert Kelsch 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(4):495-500
OBJECTIVE: Distinguishing between adenoid cystic carcinoma (ACC), polymorphous low-grade adenocarcinoma (PLGA), and monomorphic adenoma (MA) can occasionally pose a diagnostic challenge. It is of interest to identify a marker that can differentiate between these tumors. CD43 is a sialoglycoprotein that is typically expressed by hematopoietic cells and their derivative neoplasms, although positivity in epithelial tumors has been recently recognized. Our aim was to investigate CD43 immunoreactivity in ACCs, PLGAs, and MAs. STUDY DESIGN: Formalin-fixed paraffin-embedded sections from 40 salivary gland tumors (12 ACCs, 14 PLGAs, and 14 MAs) accessioned from 1989 to 2002 were retrieved from the files at the Department of Pathology, Long Island Jewish Medical Center. Immunohistochemical staining with anti-CD43 monoclonal antibody was performed. RESULTS: Cytoplasmic and membranous immunoreactivity was detected in 12/12 ACCs (100%), 1/14 PLGAs (7.1%), and 3/14 MAs (21.4%). CONCLUSIONS: CD43 appears to be preferentially expressed in salivary gland ACCs compared to PLGAs and MAs. Although the mechanism of this overexpression remains obscure at this time, our results suggest that the use of CD43 immunostaining as an adjunct to histological examination may be helpful in differentiating ACC from its mimics. 相似文献
52.
53.
The biomechanical and morphological changes in the medial collateral ligament of the rabbit after immobilization and remobilization 总被引:10,自引:0,他引:10
S L Woo M A Gomez T J Sites P O Newton C A Orlando W H Akeson 《The Journal of bone and joint surgery. American volume》1987,69(8):1200-1211
The effects of immobilization and remobilization on the biomechanical and morphological properties of the femur-medial collateral ligament-tibia complex and each of its components were investigated in the rabbit. Specimens that had been obtained after periods of unilateral immobilization of the knee and remobilization were evaluated for structural properties. In addition, the mechanical properties of the substance of the medial collateral ligament and the histological characteristics of both the substance of the ligament and its sites of insertion were evaluated. After immobilization, there were significant reductions in the ultimate load and energy-absorbing capabilities of the bone-ligament complex, and an increased number of failures occurred by tibial avulsion. The tissue of the medial collateral ligament also became less stiff as a result of immobilization. Histologically, the femoral and tibial insertion sites showed increased osteoclastic activity, resorption of bone, and disruption of the normal attachment of the bone to the ligament. With remobilization, the ultimate load and energy-absorbing capabilities of the bone-ligament complex improved but did not return to normal. Failure by tibial avulsion became less frequent, and the stress-strain characteristics of the medial collateral ligament returned to normal. Histologically, the sites of insertion of the ligament also showed evidence of recovery. 相似文献
54.
Jae Sue Choi Han Suk Young Jong Cheol Park Jin-Ho Choi Won Sick Woo 《Archives of pharmacal research》1986,9(4):233-236
The flavonoids isolated from the leaves ofRhododendron brachycarpum, were identified as quercetin, avicularin, quercitrin and hyperin. 相似文献
55.
56.
Olfactory stimulation evokes a column of activity within the olfactory bulb extending from the glomerular layer to the granule cell layer that can be visualized with 2-deoxyglucose autoradiography, optical imaging, Fos protein immunohistochemistry and c-fos mRNA in situ hybridization. The Fos response to odors is typified by the activity of relatively few juxtaglomerular cells, which often occur in foci, and a large number of granule cells extending through much of the bulb. In this study, we characterized the granule cell response to an odor for which young rats had acquired a preference. Fos-like immunoreactive granule cells were quantified by image analysis, and densely stained cells were counted in a region previously shown to be responsive to peppermint odor. We found that odor-trained pups have about half the number of Fos-immunopositive superficial granule cells which respond to a learned odor than do control pups. We then determined whether there was a correlation between the juxtaglomerular cell response and the response of the superficial granule cells deep to those glomerular layer cells. We found a positive correlation between the number of juxtaglomerular cells and the number of granule cells demonstrating Fos immunoreactivity in both control and trained pups, a relationship that changed with early olfactory training. 相似文献
57.
Background : Pelvi-ureteric junction obstruction has been increasingly diagnosed in infants, mostly as a consequence of antenatal ultrasound examinations. Methods : Of 55 infants below the age of 12 months who underwent dismembered pyeloplasty over a 7-year period, we aimed to determine the patterns and outcome of associated vesico-ureteric reflux that was present in 15 (28%) of the 53 infants in whom follow-up was available. Results : A total of eight infants had resolution of their reflux with conservative management and the median time to resolution was 15 months. Five infants proceeded to ureteroneocystotomy. Conclusions : Given the association of vesico-ureteric reflux and pelvi-ureteric junction obstruction, routine cystography is recommended when the diagnosis of pelvi-ureteric junction obstruction is made. 相似文献
58.
The hexane extract from Nutmeg, the seed ofMyristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by SiO2 column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B(II) and dehydrodiisoeugenol(III) were isolated as active principles. Compounds II and III, with a single treatment (200 mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they posses CNS-depressant properties. 相似文献
59.
Overexpression of S100A4 is closely related to the aggressiveness of gastric cancer 总被引:25,自引:0,他引:25
Cho YG Nam SW Kim TY Kim YS Kim CJ Park JY Lee JH Kim HS Lee JW Park CH Song YH Lee SH Yoo NJ Lee JY Park WS 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(5):539-545
Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea. 相似文献
60.
Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases. 相似文献