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991.
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Purpose: Amifostine (Ethyol®) is an approved cytoprotective agent prescribed to reduce certain side-effects in the chemotherapy of ovarian or non-small cell lung cancer, or in radiation treatment of head-and-neck cancer. The usefulness of this drug is further hampered, because it is not effective when given orally. The objective of this part of the project was to evaluate the radioprotective efficacy of orally active amifostine nanoparticles.

Materials and methods: Radioprotective efficacy was evaluated by measuring the ability of the amifostine nanoparticles (equivalent to 500?mg/Kg) to inhibit whole-body gamma irradiation -induced injury in mice. All mice received acute whole-body gamma irradiation from a Cesium-137 source and the radioprotective efficacy of the formulation was determined by measuring 30-day survival at 9?Gy, bone marrow hemopoeitic progenitor cell survival at 9?Gy and 8?Gy, and intestinal crypt cell survival at 11?Gy.

Results: Thirty-day survival, hemopoietic progenitor cell survival, as well as the jejunal crypt cell survival were all significantly enhanced when the mice were treated orally with the amifostine nanoparticles 1?h prior to irradiation.

Conclusions: These results clearly and unequivocally demonstrate that the amifostine nanoparticles developed in our laboratory provides significant protection from acute whole-body gamma irradiation injury in mice.  相似文献   
995.
The genetic basis of MALT lymphoma is largely unknown. Characteristic chromosomal translocations are frequently associated with gastric and pulmonary cases, but are rare at other sites. We compared the genetic profiles of 33 ocular adnexal and 25 pulmonary MALT lymphomas by 1 Mb array–comparative genomic hybridization (CGH) and revealed recurrent 6q23 losses and 6p21.2–6p22.1 gains exclusive to ocular cases. High‐resolution chromosome 6 tile‐path array–CGH identified NF‐κB inhibitor A20 as the target of 6q23.3 deletion and TNFA/B/C locus as a putative target of 6p21.2–22.1 gain. Interphase fluorescence in situ hybridization showed that A20 deletion occurred in MALT lymphoma of the ocular adnexa (8/42 = 19%), salivary gland (2/24 = 8%), thyroid (1/9 = 11%) and liver (1/2), but not in the lung (26), stomach (45) and skin (13). Homozygous deletion was observed in three cases. A20 deletion and TNFA/B/C gain were significantly associated (p < 0.001) and exclusively found in cases without characteristic translocation. In ocular cases, A20 deletion was associated with concurrent involvement of different adnexal tissues or extraocular sites at diagnosis (p = 0.007), a higher proportion of relapse (67% versus 37%) and a shorter relapse‐free survival (p = 0.033). A20 deletion and gain at TNFA/B/C locus may thus play an important role in the development of translocation‐negative MALT lymphoma. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
996.
Jacob  RA; Sandstead  HH; Klevay  LM; Johnson  LK 《Blood》1980,56(5):786-791
Hematologic indices and iron balance data were obtained on 22 normal male volunteers who were subjected to a mean +/- SD phlebotomy of 164 +/- 34 ml whole blood/mo while living in a controlled environment. Over an average stay of 5 mo, volunteers did not develop anemia, but did display a reduction in iron stores that was quantitated by measurement of serum ferritin and iron balance. The percent saturation of transferrin and the usual erythrocyte parameters did not reflect changes in iron status. Loss of iron, which was calculated from quantitative phlebotomy and iron balance data, showed that a decrease of 1 ng of serum ferritin represented a loss of 4.5 +/- 5.3 mg of iron in 10 men whose initial serum ferritins were greater than 25 ng/ml, and 25.3 +/- 58.8 mg of iron in 7 men whose initial serum ferritins were less than 25 ng/ml. The period required for 3 volunteers who consumed a self-selected mixed diet at home to replace their depleted iron stores to prephlebotomy levels was about 4.5 mo. The sensitivity of serum ferritin as an index of iron stores was affirmed. In addition it was found that normal men who were consuming a mixed diet containing about 15 mg of iron daily and losing blood at a rate of 164 +/- 34 ml/mo did not increase their iron absorption sufficiently to compensate for the iron loss.  相似文献   
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Percutaneous transcholecystic cholangiography was performed in 20 patients. Fifteen patients had normal-sized bile ducts on sonograms and computed tomographic scans, and five had partial common bile duct obstruction. Gallbladder pressures were measured in 14 patients. In all cases the intrahepatic and extrahepatic bile ducts were well visualized. Only one clinically significant complication, bile peritonitis, occurred, and it was relieved by inserting a cholecystostomy catheter. Techniques as well as the potential indications for transcholecystic cholangiography are discussed. The authors believe the transcholecystic approach is a useful alternative to transhepatic cholangiography.  相似文献   
999.
Probable Alzheimer disease: diagnosis with proton MR spectroscopy   总被引:25,自引:0,他引:25  
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1000.
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