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11.
We report that treatment of 2.2.15, a human hepatoblastoma-derived cell line in which hepatitis B virus is actively replicating, with the carbocyclic analogue of 2'-deoxyguanosine [Shealy, Y. F., O'Dell, C. A., Shannon, W. M. & Arnett, G. (1984) J. Med. Chem. 27, 1416-1421] resulted in the nearly complete cessation of viral replication, as monitored by the absence of both intracellular episomal and secreted viral DNAs and by the absence of viral DNA polymerase activity. The drug was nontoxic in concentrations up to 200 times the minimum effective inhibitory concentration.  相似文献   
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Retroperitoneal Laparoscopic Nephrectomy in Children   总被引:1,自引:0,他引:1  
Retroperitoneal pediatric laparoscopic nephrectomy is described in 3 patients requiring 3 to 5 hours with an estimated blood loss of 10 to 60 cc. The children returned to school within 7 days postoperatively. Advantages of this procedure include the avoidance of intraoperative repositioning of the patient and easy conversion to an open lumbodorsal approach, if necessary; early laparoscopic visualization of the renal artery; applicability in cases of previous abdominal surgery, and avoidance of intraperitoneal adhesion.  相似文献   
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A series of 1-[1-arylcyclohexyl]-1,2,3,6-tetrahydropyridines were prepared by the reaction between 1-(1-cyanocyclohexyl)-1,2,3,6-tetrahydropyridine (1) and an appropriately substituted Grignard reagent. The resulting compounds were tested for their phencyclidine binding site affinities. Selected compounds were then tested for their ability to produce ketamine appropriate responding in monkeys and/or to show neuroprotective effects in a baby rat hypoxia/ischemia model. While it was found that binding site affinity correlated well with discriminative stimulus effects, it was found to be a poor indicator of neuroprotective efficacy within this series.  相似文献   
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Disaggregation of bone into crystals   总被引:6,自引:0,他引:6  
Summary The sizes, shapes, and organizational states of the crystals in bone are studied by systematic disaggregation of the mineral phase. This is achieved by oxidizing the organic phase with sodium hypochlorite, dispersing the resultant particles by sonication, and separating the crystal aggregates from the crystal monomers by gravity setting in ethanol. Six different bones are compared. Bones in which crystals are intimately associated with the collagen fibrils mostly disaggregate into crystal monomers. In dense bones, where the crystals are mostly located between fibrils, they tend to persist as “fused” aggregates. All the crystals are tabular or plate-shaped. In bones in which the majority of crystals are associated with the collagen fibrils, just less than 90% of the crystals are shorter than about 450 ? in length. Their widths are on the average about 250 ?, almost an order of magnitude larger than the diameters of individual gap regions within the collagen fibril. The notion that one crystal is located in one gap region is therefore untenable and a reevaluation of the relations between collagen and mineral in bone is necessary.  相似文献   
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