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41.
Mouse monoclonal antibodies (mAbs) were produced against an Indian isolate of egg drop syndrome (EDS)virus and characterized. Four hybridoma clones were secreting mAbs that bound to a 100 kDa protein,presumably the hexon protein. These mAbs were found to cross-react with two other Indian isolates of EDSvirus and to the reference UK 127 strain. Three of these mAbs were mapped to the same epitope compared withthe other mAb (F8), which bound to a different epitope. An antigen-capture enzyme-linked immunosorbentassay (AC-ELISA) was developed using the F8 mAbs as capture antibody and polyclonal chicken serum againstEDS virus as detection antibody. A polymerase chain reaction (PCR) was used to detect the EDS viral genome.Following experimental infection of oestrogen-treated chickens with EDS virus, cloaca1 swabs, oviduct, uterusand spleen were collected at different days post-infection and used in both AC-ELISA and PCR, directly andafter a single passage in embryonated duck eggs. The sensitivity and specificity of antigen detection by ACELISAor PCR was 95% and 98%, respectively. For diagnosis of EDS viral infections, PCR is recommendeddue to its ease and the lack of requirement of prepared reagents such as mAbs or conjugates. We recommendthat PCR be performed directly on boiled tissue homogenates. Any negative samples may be passaged inembryonated duck eggs and the allantoic fluids tested by PCR before a conclusive negative diagnosis is given.  相似文献   
42.
From 1980 to 1991, 29 patients underwent complex reconstruction following extremity sarcoma resection. Soft tissue was the site of origin in 15 patients (52%) and bone was the site of origin in 14 patients (48%), with 20 sarcomas (69%) in the lower extremity. Resection consisted of the following procedures: extended anatomical soft-tissue resections (21 patients [72%]), bone resections (18 patients [62%]), and joint resections (14 patients [48%]). Reconstruction involved the following: myocutaneous flaps (20 patients [69%]), joint prosthesis (eight patients [28%]), and bone reconstruction (15 patients [52%]). There was no surgical mortality; one patient required an amputation owing to surgical complications. The site of the first failure was local (four [31%] of 13 patients), lung (five patients [38%]), others (four patients [31%]). At a median follow-up of 23 months, 18 patients (62%) had no evidence of disease, 27 (93%) had no local disease, 21 (72%) had good extremity function, three (10%) had major disabilities, and five (17%) underwent amputations. Local control improved when the margin of resection was larger than 10 mm. Disease-free survival was 67% at 3 years. Overall survival was 51% at 5 years. Tumor size was an independent predictor of overall survival. Local recurrence did not affect overall survival.  相似文献   
43.
CTCF, a conserved, ubiquitous, and highly versatile 11-zinc-finger factor involved in various aspects of gene regulation, forms methylation-sensitive insulators that regulate X chromosome inactivation and expression of imprinted genes. We document here the existence of a paralogous gene with the same exons encoding the 11-zinc-finger domain as mammalian CTCF genes and thus the same DNA-binding potential, but with distinct amino and carboxy termini. We named this gene BORIS for Brother of the Regulator of Imprinted Sites. BORIS is present only in the testis, and expressed in a mutually exclusive manner with CTCF during male germ cell development. We show here that erasure of methylation marks during male germ-line development is associated with dramatic up-regulation of BORIS and down-regulation of CTCF expression. Because BORIS bears the same DNA-binding domain that CTCF employs for recognition of methylation marks in soma, BORIS is a candidate protein for the elusive epigenetic reprogramming factor acting in the male germ line.  相似文献   
44.

Objective  

To evaluate the role of 68Ga-labelled [1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid]-1-NaI3-Octreotide (68Ga-DOTA-NOC) whole body positron emission tomography-computed tomography (PET-CT) as a functional imaging approach for phaeochromocytoma and paraganglioma.  相似文献   
45.
Thyrotoxicosis due to functioning metastases from thyroid cancer is rare. It also presents a therapeutic challenge, as both the metastatic cancer and thyrotoxicosis need to be treated. We present here two cases of thyrotoxicosis which on a routine (99m)Tc-pertechnetate thyroid scan showed extrathyroidal foci of uptake. Two patients who initially presented with thyrotoxicosis underwent a routine thyroid scan. Abnormal uptake in the shoulder was incidentally noted, which prompted us to do a whole body pertechnetate scan in the same sitting, which revealed extensive hyperfunctioning metastases in the lungs and bones. We also discuss the 'Flip Flop' phenomenon in thyroid cancer, which was seen in our case. This report emphasizes the importance of evaluating the abnormal foci of uptake seen on a routine thyroid scan.  相似文献   
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