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The authors report their 4-year (1984-1988) experience with TCE in the treatment of primary sacral benign/malignant and vascular bone tumors, after similar preliminary studies on aneurysmal bone cysts. Eleven patients were treated, for a total of 21 procedures: in 85% of the eight cases of palliative embolization, multiple instrumental approaches were needed for late revascularization, up to four consecutive embolizations in the same patients. Severe complications were observed in 19% of the procedures, due to arterial catheterization and/or instrumental maneuvers, but in none of them was surgery required. Technical results--i.e. devascularization of the mass--were optimal/suboptimal in all cases at the end of multiple procedures in the same patient: in 7/8 patients treated for palliation, however, the treatment was repeated, the late venous DSA angiographic control showing recanalization of the great vessels surrounding the lesion and/or revascularization through collateral channels. The analysis of morphological and clinical results (with reference to pain relief, dimension of the mass, and calcification at CT follow up) showed a complete pain relief in 100% of the patients treated preoperatively for palliation. The dimension of the mass was reduced in 12.5% of the cases treated for palliation, and recalcification was demonstrated on CT in 12.5% of cases. In 25.5% the mass had increased in size and in 62.5% its dimensions were unchanged. Effective pain relief was always obtained in the cases treated preoperatively. Thus, in our experience TCE of expansive lesions of the sacral bone can be considered as an effective therapeutical choice, with special reference to pain relief, for use in all inoperable cases, and as a preoperative treatment to minimize blood loss at surgery. Still, embolization materials are not completely satisfying: many of them are expensive, difficult to use and cannot be trusted to permanently occlude the vessels, which forces to intervene more than once to obtain optimal clinicomorphological results. As for malignant lesions, chemo-embolization with cytostatic substances should be used to improve the efficacy of the method. However, even through such negative judgements can be expressed on TCE, both technical and clinical results have been, in our experience, quite satisfactory, which calls for optimization of the methodology.  相似文献   
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Predominance of null mutations in ataxia-telangiectasia   总被引:15,自引:4,他引:15  
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving cerebellar degeneration, immunodeficiency, chromosomal instability, radiosensitivity and cancer predisposition. The responsible gene, ATM, was recently identified by positional cloning and found to encode a putative 350 kDa protein with a Pl 3-kinase-like domain, presumably involved in mediating cell cycle arrest in response to radiation-induced DNA damage. The nature and location of A-T mutations should provide insight into the function of the ATM protein and the molecular basis of this pleiotropic disease. Of 44 A-T mutations identified by us to date, 39 (89%) are expected to inactivate the ATM protein by truncating it, by abolishing correct initiation or termination of translation, or by deleting large segments. Additional mutations are four smaller in-frame deletions and insertions, and one substitution of a highly conserved amino acid at the Pl 3-kinase domain. The emerging profile of mutations causing A-T is thus dominated by those expected to completely inactivate the ATM protein. ATM mutations with milder effects may result in phenotypes related, but not identical, to A-T.   相似文献   
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As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.   相似文献   
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In this study, we have used time-lapse video cinematography to study fertilization in 50 human oocytes that had undergone intracytoplasmic sperm injection (ICSI). Time-lapse recording commenced shortly after ICSI and proceeded for 17-20 h. Oocytes were cultured in an environmental chamber which was maintained under standard culture conditions. Overall, 38 oocytes (76%) were fertilized normally, and the fertilization rate and embryo quality were not significantly different from 487 sibling oocytes cultured in a conventional incubator. Normal fertilization followed a defined course of events, although the timing of these events varied markedly between oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular waves of granulation within the ooplasm which had a periodicity of 20-53 min. The sperm head decondensed during this granulation phase. The second polar body was then extruded, and this was followed by the central formation of the male pronucleus. The female pronucleus formed in the cytoplasm adjacent to the second polar body at the same time as, or slightly after, the male pronucleus, and was subsequently drawn towards the male pronucleus until the two abutted. Both pronuclei then increased in size, the nucleoli moved around within the pronuclei and some nucleoli coalesced. During pronuclear growth, the organelles contracted from the cortex towards the centre of the oocyte, leaving a clear cortical zone. The oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during the course of the observation period. The female pronucleus was significantly smaller in diameter than the male pronucleus (24.1 and 22.4 microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0 respectively, P < 0.0001). After time-lapse recording, oocytes were cultured for 48 h prior to embryo transfer or cryopreservation. Embryo quality was related to fertilization events and periodicity of the cytoplasmic wave, and it was found that good quality embryos arose from oocytes that had more uniform timing from injection to pronuclear abuttal and tended to have a longer cytoplasmic wave. In conclusion, we have shown that time-lapse video cinematography is an excellent tool for studying fertilization and early embryo development, and have demonstrated that human fertilization comprises numerous complex dynamic events.   相似文献   
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Doppman  JL; Brennan  MF; Dunnick  NR; Kahn  CR; Gorden  P 《Radiology》1981,138(3):557-562
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production.  相似文献   
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Nineteen aneurysmal bone cysts and five angiomas of bone were treated by selective arterial embolization. The median follow-up was 22 months. In 17 patients healing occurred with complete relief of symptoms; in 11 of these almost complete ossification of the lesion resulted. In the remaining cases, little or no ossification was apparent but ossification may take 1 year or more to occur. No recurrence was observed in any of these cases. Recurrence occurred only in two cases. In one, growth of the recurrence stopped after a second embolization, and the X-rays showed no change. Selective arterial embolization represents a treatment of choice in aneurysmal bone cyst and angioma of bone especially of the spine, sacrum, or pelvis. In these sites embolization replaces surgery which might be hazardous due to intraoperative bleeding.Supported in part with Rizzoli Research Funds  相似文献   
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