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31.
Retinoblastoma. A clinical, immunohistochemical, and electron microscopic case report 总被引:2,自引:0,他引:2
A 4-year, 9-month-old boy had a history of leukocoria of the right eye for approximately six months prior to admission. The other eye was normal. There was no family history of retinoblastoma. Funduscopy disclosed a large white mass extending from the nasal pars plana to the mid-pupillary zone and the posterior pole with a near total retinal detachment in the superior temporal quadrant. A B-scan ultrasound showed an echo dense area of the anterior portion of the mass. A CT scan showed intraocular tissue densities with no evidence of optic nerve involvement or extraocular extension. Immunohistochemistry of a fresh frozen portion of tumor revealed reactivity with antibodies directed against interphotoreceptor retinoid-binding-protein (IRBP), neuron-specific enolase, glial fibrillary acidic protein, S-antigen, focal reactivity with opsin, and scattered cytoplasmic staining for cyclic GMP and cyclic GMP phosphodiesterase. Biochemical analysis of fresh frozen tissue samples confirmed the presence of IRBP. Transmission electron microscopy disclosed occasional Flexner-Wintersteiner rosettes connected by zonula adherens-like junctions. These showed inner segment-like structures containing prominent mitochondria, portions of cilia and fragments of outer segment material. These data, along with the immunocytochemistry indicates a predominant neuronal nature of the tumor cells with significant photoreceptor-like differentiation. 相似文献
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33.
Splenic T cells from myelin basic protein (MBP)-immunised Lewis rats were activated to transfer experimental autoimmune encephalomyelitis (EAE) by co-culture with MBP-pulsed lymphoid dendritic cells (DC). MBP-pulsed DC could be kept for at least 24 h at 37 degrees C in antigen-free medium without affecting their ability subsequently to activate encephalitogenic T cells. However, MBP-pulsed DC were rendered much less stimulatory after a 6 h, but not 2 h, secondary incubation with ovalbumin. Thus, although encephalitogenic complexes between MBP and DC appear very stable in the absence of competing antigens, in their presence, antigen exchange can take place over a period of a few hours; this has positive implications for therapy of EAE by antigen competition. 相似文献
34.
A comparison of presenting characteristics of patients with intracapsular and extracapsular proximal femoral fractures.
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M J Parker G A Pryor J K Anand R Lodwick J W Myles 《Journal of the Royal Society of Medicine》1992,85(3):152-155
The presenting characteristics of 1423 consecutive admissions with proximal femoral fractures were prospectively studied, to determine any differences that may exist between patients, dependent on the radiological site of the fracture. Patients with intracapsular fractures were of a lower average age, more mobile, less likely to use walking aids or live in residential accommodation, they also had a considerably shorter length of hospital stay than for those patients with extracapsular fractures. Comparison against previous series shows that the average age of hip fracture patients and the proportion of trochanteric fractures is increasing. 相似文献
35.
J E Gervasoni R N Taub M T Yu D Warburton M Sabbath S Gilleran D L Coppock J D'Alessandri S Krishna M Rosado 《Cancer research》1992,52(19):5244-5249
Anthracycline-resistant HL-60/AR cells and their drug-sensitive HL-60/S counterparts were characterized by karyotypic analysis and examined for the overexpression of DNA and mRNA sequences coding for P-glycoprotein (Pgp). The HL-60/S cells were karyotypically stable over a 5-year period of study (1986-1991), except for an additional small Giemsa-positive band noted at 7q22 in cultures harvested in 1987, but not in 1986. This change did not affect drug sensitivity. The drug-resistant HL-60/AR cells examined in 1986, 1987, and 1991 demonstrated a very stable karyotype. The most striking feature was a large homogeneously staining region in the long arm of chromosome 7 (7q11.2), and translocation of the remainder of the long arm to another centromere. Other changes in the HL-60/AR cells included inversion in 9q, partial deletion of the short arm of chromosome 10p, addition of material to the p arm of der(16), loss of chromosome 22, and the appearance of a new marker chromosome. Both HL-60/S and the HL-60/AR cells were found not to amplify DNA or mRNA sequences coding for the Pgp. Thus, although the HL-60/AR cells possess the classical multidrug resistance phenotype and demonstrate a homogeneously staining region near the region of the MDR1 gene, their resistance is due to mechanisms other than those coded for by MDR1. 相似文献
36.
A K Rama Krishna Shivanand Patil Grs Srinivas Rao Ajit Kumar 《Indian journal of gastroenterology》2006,25(2):97-98
Gastrointestinal manifestations of dengue fever are mainly in the form of bleeding or liver function abnormalities. Dengue fever presenting as acute colitis-like picture is not reported to date. We report a 50-year-old man with dengue fever presenting with lower gastrointestinal bleeding and colonoscopic features of acute inflammatory colitis. 相似文献
37.
38.
Aim: To study the prevalence of filtration-bleb transconjunctival oozing in the first postoperative year after various glaucoma procedures. Methods: Cross-sectional, single-point examination of all filtration blebs in eyes which had glaucoma surgery in the last year. Eyes were examined 3-12 months after surgery and were grouped into non-penetrating (NPGS) and penetrating (PGS) 相似文献
39.
Anand N Arora S Clowes M 《世界核心医学期刊文摘》2006,2(5):21-22
目的:前瞻性研究青光眼术中应用丝裂霉素C(MMC)对于结膜滤过泡高危因素如无血管化、经结膜的渗漏(TCO)和滤过泡裂孔的影响。方法:一位观察者对进行了青光眼手术联合MMC的125例连续患者的125只眼进行为期2年的前瞻性研究,这些患者最初都成功地建立了滤过通道。巩膜瓣切开前将MMC置于该区,多数患者MMC0.2g/L持续2min。青光眼手术包括小梁切除术、深巩膜切除术和联合手术。将干燥的荧光素试纸置于滤过泡的无血管区,以观察房水外流[点渗漏(PL)或未流出(TCO)]。 相似文献
40.
Previous work from this laboratory has already indicated that capsaicin, stabilizes the rat lung membrane lipid system on long-term treatment. This stabilization of the membrane is further supported by our present findings that capsaicin pretreatment causes significant inhibition of various chemically induced lipid peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes induced by different chemical irritants such as chloroform, dichloromethane, carbon tetrachloride as well as ferrous sulphate. 相似文献