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991.
992.
Cigliano B De Franciscis A Palazzo G Pisanti A Rufolo L Di Martino L 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》1999,7(2):125-128
As there has recently been a significant increase in childhood tuberculosis, we considered an important contribution the clinical case of an infant from Brazil, who underwent right bilobectomy to treat a previously poorly cured enlarged pulmonary tubercular infiltrate. 相似文献
993.
Adenoviruses from human immunodeficiency virus-infected individuals, including two strains that represent new candidate serotypes Ad50 and Ad51 of species B1 and D, respectively 下载免费PDF全文
De Jong JC Wermenbol AG Verweij-Uijterwaal MW Slaterus KW Wertheim-Van Dillen P Van Doornum GJ Khoo SH Hierholzer JC 《Journal of clinical microbiology》1999,37(12):3940-3945
Adenovirus (Ad) isolates from a large number of human immunodeficiency virus (HIV)-infected individuals were compared serologically and genetically with Ad isolates from immunocompetent patients. Between 1982 and 1994, stool and urine samples from 137 subjects with AIDS hospitalized in The Netherlands yielded 143 Ad strains. Forty additional Ad strains were obtained from 35 HIV-positive patients in Manchester, United Kingdom, in 1992 and 1993. Of these 183 HIV-associated Ad strains, 84% belonged to species D and 3% belonged to species C. These strains were compared with 2,301 Ad strains collected during general diagnostic examinations in The Netherlands from 1973 to 1992. Of the latter strains, 5% belonged to species D and 49% belonged to species C. Two of the Ads isolated from fecal specimens of AIDS patients represent new serotypes: candidate Ad serotype 50 (prototype strain, Wan) of subspecies B1 and candidate Ad serotype 51 (prototype strain, Bom) of species D. The DNA restriction enzyme patterns of strains Wan and Bom differed from the patterns of all established prototypes. 相似文献
994.
Structural and functional macrophages alterations by ceramics of different composition 总被引:2,自引:0,他引:2
Bosetti M Ottani V Kozel D Raspanti M De Pasquale V Ruggeri A Cannas M 《Biomaterials》1999,20(4):363-370
Biomaterials may initiate several and complex biological reactions in host tissues, and the cell-biomaterial interactions can determine the release of mediators including monocytes and lymphocytes chemotactic factors. The present work was aimed to investigate in vitro the macrophage biological reactions of a natural apatite obtained by heat treatment at 400 degrees C of bovine bone, compared to other ceramics usually used for dental and orthopedic applications, using synthetic apatite and three types of alumina as controls. Particles chemotactic activity and powders oxidative burst evidenced no monocyte macrophages sensitivity reaction for natural and synthetic hydroxyapatite powders at great granulometry (> 50 microm); data were confirmed by ultrastructural observations; electron microscopy analysis showed macrophages with the features of healthy cells in the presence of both natural and synthetic apatites while macrophages grown in the presence of alumina seemed to be negatively affected. In conclusion, among all ceramics tested, natural apatite displayed a good compatibility with living cells, being better tolerated than synthetic hydroxyapatite which in turn is better tolerated than alumina. 相似文献
995.
Lo Cunsolo C Iolascon A Cavazzana A Cusano R Strigini P Mazzocco K Giordani L Massimo L De Bernardi B Conte M Tonini GP 《Cancer Genetics and Cytogenetics》1999,109(2):126-130
Familial neuroblastoma occurs rarely. We studied a family with three children; one of them has a disseminated (stage 4) and another has a localized (stage 2) neuroblastoma. We observed subtelomeric locus D1Z2 (1p36) deletion in both tumors by using double-color fluorescence in situ hybridization. The MYNC gene was found in single copy in both tumors. Loss of heterozygosity (LOH) and restriction fragment length polymorphism analyses were performed by using DNA from frozen tumor cells and from microdissected tumor areas excised from paraffin-embedded sections. We detected somatic LOH at locus D1S468 (1p36) in a tumor-cell population with a trisomy 1 of the stage-2 patient. Neuroblastoma cells of the stage-4 patient were diploid and showed allelic loss at the following loci: D1S172, D1S80, D1S94, D1S243, D1S468, D1S214, D1S241, and D1S164. Haplotype study showed that the siblings inherited the same paternal 1p36-->pter chromosome region by homologous recombination and that, in the two tumors, arm 1p of different chromosomes of maternal origin was damaged. Our results suggest that the siblings inherited the predisposition to neuroblastoma associated with paternal 1p36 region and that tumors developed as a consequence of somatic loss of the maternal 1p36 allele. 相似文献
996.
Progressive amplification and overexpression of the eukaryotic initiation factor 4E gene in different zones of head and neck cancers. 总被引:9,自引:0,他引:9
D L Sorrells G E Ghali A De Benedetti C A Nathan B D Li 《Journal of oral and maxillofacial surgery》1999,57(3):294-299
PURPOSE: Eukaryotic initiation factor 4E (eIF4E) binds to mRNA as the initial rate-limiting step in protein synthesis. Amplification and overexpression of the eIF4E gene has been associated with malignant transformation. The objectives of this study were to 1) quantify the eIF4E gene in head and neck squamous cell carcinoma (HNSCC) specimens, 2) quantify eIF4E protein elevation and examine its association with eIF4E gene amplification, and 3) determine whether there is progression in eIF4E gene amplification and protein overexpression in the tumor-free resection margin, the transition zone, and the tumor core of HNSCC specimens. MATERIALS AND METHODS: Eighteen HNSCC specimens were divided into three zones: 1) tumor core; 2) transition zone; and 3) "tumor-free" margin. Competitive polymerase chain reaction was performed to determine eIF4E gene copy number. eIF4E protein expression was quantified using Western blot analysis. RESULTS: All 18 HNSCC specimens tested had significant eIF4E gene amplification (4.3+/-1.2; P < .05). In contrast, none of the 10 benign specimens from noncancer patients had any eIF4E gene amplification (1.1+/-0.5). In the 12 HNSCC specimens examined for the three zones, the tumor core and transition zone showed eIF4E gene amplification (5.2+/-1.1 and 3.5+/-0.9, respectively) compared with the "tumor-free" margin (2.1+/-1.1; P < .05). The tumor core and transition zone showed significant efF4E protein elevation (15.5+/-9.3, 4.4+/-4.6, respectively) compared with the "tumor-free" margin (0.9+/-0.5, P < .05). CONCLUSIONS: The eIF4E gene is amplified and overexpressed in HNSCC. Amplification and elevation of eIF4E were highest in the tumor core, intermediate in the transition zone, and lowest in the tumor-free margin. There appears to be progression of eIF4E gene amplification and overexpression from the "tumor-free" margin to the tumor core. 相似文献
997.
视频显示终端脉冲磁场对细胞间隙连接通讯功能的影响研究 总被引:1,自引:0,他引:1
目的:研究视频显示终端(VDT)脉冲磁场对细胞间隙连接通讯功能的影响。方法:用15.6kHz、峰值强度为200 μT的脉冲磁场(PMF)和(或)十四酰基咐拜醇酯(TPA:5 ng/m l)对培养的中国仓鼠肺成纤维细胞(CHL)进行辐射24 h,采用离子电渗注射法观察荧光黄向与其接触的周围细胞的传递情况。结果:TPA对细胞间隙连接通讯(GJIC)功能具有抑制作用,与空白对照组相比有显著差异(P< 0.01),单纯VDT组对GJIC无抑制作用(P> 0.05),亦未见该脉冲磁场对TPA的抑制作用有增强效应。结论:视频显示终端脉冲磁场(15.6 kHz)对细胞间隙连接通讯功能无直接和(或)协同TPA的抑制作用 相似文献
998.
999.
Characterization of cystic tumors of the pancreas: CT accuracy 总被引:4,自引:0,他引:4
Procacci C Biasiutti C Carbognin G Accordini S Bicego E Guarise A Spoto E Andreis IA De Marco R Megibow AJ 《Journal of computer assisted tomography》1999,23(6):906-912
PURPOSE: The purpose of this work was to evaluate the capabilities of CT to accurately characterize cystic tumors of the pancreas. METHOD: Two observers retrospectively evaluated the CT exams of 100 cystic masses of the pancreas, with pathological confirmation. The two observers, blinded about clinical information and the final diagnosis, tried to categorize the lesions according to well established morphologic features. Statistical analysis was performed to measure the agreement between each radiologist and the consensus diagnosis and to evaluate the usefulness of certain CT findings in differentiating one type of cystic pancreatic neoplasm from another. RESULTS: Serous cystadenoma was better diagnosed by CT [Youden misclassification index (Ymi) = 0.72] than mucinous cystic tumor (Ymi = 0.44) and solid pseudopapillary tumor (cystic variant) (Ymi = 0.47). CONCLUSION: As patients with previous history of pancreatitis were excluded from the study, CT findings allowed correct characterization of only 60% of cystic pancreatic masses. Among the remaining 40%, 15-20% of the wrong diagnoses could not be corrected by means of CT, given the patterns shown by the tumors. In 20-25% of the cases, a nonspecific diagnosis of cystic mass was made. 相似文献
1000.
Mertens IJ De Klerk JM Zelissen PM Thijssen JH Sie-Go DM Han SH Van Rijk PP 《Clinical nuclear medicine》1999,24(5):346-349
The case of a 54-year-old woman with metastatic follicular thyroid cancer and undetectable serum thyroglobulin is presented. Many years after the patient had a subtotal thyroidectomy for a large goiter that had no clear evidence of malignancy, metastatic bone disease developed. When the bone metastases were detected and during the follow-up period, serum thyroglobulin values remained undetectable, but radioiodine uptake in the metastases was abundant. This case indicates that the combination of 1-131 scintigraphy and serum thyroglobulin values is superior to the measurement of serum thyroglobulin alone in detecting well-differentiated, metastatic thyroid cancer. 相似文献