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991.
992.
Zalata KR Leech SH Ming SC Nasif WA Nada NA Mohamed IE Atallah AM Gad-el-Hak NA 《Hepato-gastroenterology》2002,49(47):1225-1229
BACKGROUND/AIMS: p53 gene mutation occurs in about 50-60% of colorectal carcinoma cases. This mostly occurs as a late event in the adenoma-carcinoma sequence. These late stages are associated with more aneuploidy compared to adenomas and early carcinomas. However there is a controversy regarding the relation between p53 overexpression and DNA index. This study was designed to investigate the relationship between p53 status and DNA ploidy pattern. METHODOLOGY: Nuclear DNA content of paraffin-embedded material from 83 colectomy specimens for colorectal carcinoma was measured by flow cytometry. Also, p53 was detected by immunohistochemistry in 73 out of the 83 tumor cases using a monoclonal antibody that detects both wild and mutant p53 proteins (Biogenex 1801). RESULTS: Aneuploidy was identified in 37 cases (46.25%). Tumors with rectal location were significantly more aneuploid in comparison to other sites (P = 0.009), p53 staining showed three patterns: diffuse staining (29 cases), focal (13 cases), and negative (31 cases). Diffuse p53 staining was associated with aneuploidy (P = 0.04). The majority of DNA indices fell within the range 1.1-2.2 (32 out of 37). Twenty-one of these had DNA index = 1.1-1.8 (aneuploidy short of tetraploidy) significantly associated with diffuse p53 staining compared with peritetraploid cases (DNA index 1.8-2.2) (P = 0.034). CONCLUSIONS: p53 immunohistochemistry demonstrates two distinct patterns in colorectal carcinoma. Diffuse p53 staining, which is associated with aneuploidy short of tetraploidy (DNA index 1.1-1.8), a finding which is different from previously published work. Focal p53 staining pattern, in contrast, is related to high G2M and more abnormal tetraploid peaks but less aneuploidy. 相似文献
993.
We have previously reported that the synthetic cannabinoid R-(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4-benzoxazin-yl]-(1-naphthalenyl)methanone mesylate (WIN55,212-2) causes a selective inhibition of paired pulse depression of population spikes recorded from the CA1 region of rat hippocampal slices maintained at 28-30 degrees C. We now show that this effect is highly temperature-dependent and that WIN55,212-2 actually increases paired pulse depression of population spikes recorded from slices maintained at 35 degrees C. This temperature dependence was found to correlate with the effects of the known gamma-amino butyric acid (GABA)-uptake inhibitors, nipecotic acid and guvacine, which were without effect at 28-30 degrees C, but increased paired pulse depression at 35 degrees C. The results show that the effects of cannabinoids on synaptic transmission in the hippocampal slice are highly temperature-dependent and it is suggested that this is due to the presence of increased GABA uptake at higher temperatures. 相似文献
994.
Pancreatic involvement in sarco?dosis is exceptional. We report a case of pancreatic sarco?dosis diagnosed during the etiologic work-up done for a pancreatic mass associated to a polyadenopathy. Under corticotherapy evolution is favorable with regression of the pancreatic lesions. 相似文献
995.
Sehili S Bouzaidi K Belhadj Hassine S Sassi R Kochlef A Khayat O Ayed M Ghorbel A Daghfous MH 《La Tunisie médicale》2002,80(5):292-295
The splenic angioma is a rare tumour. Its aspects MRI are still badly known. The authors show that in the 2 brought back cases, there is a hypersignal on the 3 echoes of T2 with a catch of contrast slow and centripetal after Gadolinium injection. The hemorrhagic risk in connection with a spontaneous or traumatic rupture imposes the identification of this lesion. 相似文献
996.
GJ Fuchs P Tienboon MA Khaled S Nimsakul S Linpisarn AS Faruque Y Yutrabootr M Dewier RM Suskind 《Archives of disease in childhood》1997,76(6):509-512
Twelve thalassaemic children under 3 years of age received intensive nutritional support for one month and were discharged on a prescribed diet of locally available foods. Anthropometry, bioelectrical impedance analysis and dietary intake were longitudinally assessed. Mean energy intake was 20% greater than the recommended daily allowance during nutritional supplementation as compared with below the recommended daily allowance before and after the period of nutritional support. Weight, but not height, significantly increased during the support period and was due to increases in both fat free mass and fat mass. Body weight, fat free mass and fat mass declined in line with the reduced intake upon return home; however, height velocity accelerated and exceeded normal through the fourth month before resuming a below normal rate. It can be concluded that (1) nutritional stunting as the result of reduced nutrient intake is an important cause of growth failure in young children with thalassaemia and is responsive to nutritional support, (2) the deficit in height velocity was due to retarded truncal height growth, and (3) the bioelectrical impedance analysis method is suitable for body composition analysis of thalassaemic children. 相似文献
997.
Loss of Y chromosome in bilharzial bladder cancer 总被引:4,自引:0,他引:4
Bilharzial bladder cancer is the most common malignant neoplasm in Egypt, also occurring with a high incidence in other regions of the Middle East and East Africa. In a previous study, using centromere probes specific for chromosomes 3, 4, 7-11, 16, and 17, we demonstrated that monosomy of chromosome 9 (48.4%), and numerical aberrations of chromosome 17 (19.4%) were the most common observed imbalances. The present study extends the establishment of the baseline cytogenetic profile of this type of malignancy. Interphase cytogenetics by fluorescence in situ hybridization with the use of a panel of centromere-associated DNA probes for chromosomes 1, 2, 5, 6, 12, 13/21, 14, 15, 18, 19, 20, X, and Y was performed on paraffin-embedded bladder specimens from 25 Egyptian patients affected with bilharzial bladder cancer. No numerical aberrations were detected in the 25 cases for chromosomes 1, 2, 5, 6, 12, 13/21, 14, 15, 18, 19, 20, and X. However, loss of chromosome Y was observed in 7 of the 17 male cases studied (41.2%). No significant correlation was observed between loss of the Y chromosome and any of the different clinicopathologic characteristics of these cases. These data suggest that loss of the Y chromosome is the second frequent event that can occur in bilharzial bladder cancer. A molecular genetic model of bilharzial bladder cancer is evolving. 相似文献
998.
Wafaa A Tawfik Khaled A Shams Nahla S Abdel-Azim Nahed M Hassan Shams I Ismail 《African journal of traditional, complementary, and alternative medicines》2007,4(1):55-58
The roots of Alkanna orientalis (L.) Boiss yielded α- methyl-n-butyl alkannin (compound 1) and alkannin acetate (compound 2). The compounds were identified by UV, MS, 1H NMR and 13C NMR. Quantitative determination of α- methyl-n-butyl alkannin and alkannin acetate in Alkanna orientalis (L) Boiss roots was established by TLC densitometry. 相似文献
999.
Gamma Interferon (IFN-γ) and IFN-γ-Inducing Cytokines Interleukin-12 (IL-12) and IL-18 Do Not Augment Infection-Stimulated Bone Resorption In Vivo 下载免费PDF全文
Hajime Sasaki Khaled Balto Nobuyuki Kawashima Jean Eastcott Katsuaki Hoshino Shizuo Akira Philip Stashenko 《Clinical and Vaccine Immunology : CVI》2004,11(1):106-110
Periapical granulomas are induced by bacterial infection of the dental pulp and result in destruction of the surrounding alveolar bone. In previous studies we have reported that the bone resorption in this model is primarily mediated by macrophage-expressed interleukin-1 (IL-1). The expression and activity of IL-1 is in turn modulated by a network of Th1 and Th2 regulatory cytokines. In the present study, the functional roles of the Th1 cytokine gamma interferon (IFN-γ) and IFN-γ-inducing cytokines IL-12 and IL-18 were determined in a murine model of periapical bone destruction. IL-12−/−, IL-18−/−, and IFN-γ−/− mice were subjected to surgical pulp exposure and infection with a mixture of four endodontic pathogens, and bone destruction was determined by microcomputed tomography on day 21. The results indicated that all IL-12−/−, IL-18−/−, and IFN-γ−/− mice had similar infection-stimulated bone resorption in vivo as wild-type control mice. Mice infused with recombinant IL-12 also had resorption similar to controls. IFN-γ−/− mice exhibited significant elevations in IL-6, IL-10, IL-12, and tumor necrosis factor alpha in lesions compared to wild-type mice, but these modulations had no net effect on IL-1α levels. Recombinant IL-12, IL-18, and IFN-γ individually failed to consistently modulate macrophage IL-1α production in vitro. We conclude that, at least individually, endogenous IL-12, IL-18, and IFN-γ do not have a significant effect on the pathogenesis of infection-stimulated bone resorption in vivo, suggesting possible functional redundancy in proinflammatory pathways. 相似文献
1000.
Mrad K Charfi L Dhouib R Ghorbel I Sassi S Abbes I Driss M Ben Romdhane K 《Annales de pathologie》2004,24(5):446-9; quiz 393
Extra nodal involvement by Rosa?-Dorfman disease (RDD) is not rare but remains poorly described clinically and microscopically. We report a case of RDD involving the thyroid and revealed by a 15 mm cold nodule developed on an ancient goiter. The patient was a 53 year old North African woman. She also presented an involvement of cervical lymph nodes, respiratory tract and right kidney. Microscopic analysis of thyroid revealed a diffuse and dense infiltrate of large pale histiocytes with few features of lymphophagocytosis. To the best of our knowledge, this is the fifth case reported in the literature. In previous reported cases, thyroid RDD was associated to constant lymph node involvement (massive lymphadenopathy in 3 cases and occult in one case) and no other extra nodal localization except the respiratory tract in one case. The characteristic features of lymphophagocytosis must be searched with great care. 相似文献