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61.
Sixty four patients were referred for cardiac transplantation from a single cardiac team at this hospital between October 1984 and December 1986. Of these patients, 33 were referred for urgent transplantation, all of whom required intensive treatment in hospital with intravenous infusions of cardiac drugs, intra-aortic balloon counterpulsation, peritoneal dialysis, ventilation, or any combination of these to sustain life. Of these 33 patients, six died while awaiting transplantation, one was removed from the waiting list for a transplant, and 26 received cardiac transplants. There were five deaths within 24 hours of operation and one death 10 days after the operation. Twenty of those who had surgery had a successful outcome of transplantation, but there was one late death 10 weeks postoperatively and a further death 31 months after surgery. Eighteen patients were alive and well 10 to 33 months (mean 19·4 months) after transplantation, with an overall survival rate after surgery of 69%.Provided that surgery can be performed before renal failure has progressed such that renal transplantation is necessary, the results are excellent (surgical survival 85·5%) and, we believe, justify the expenditure and staffing requirements necessary to treat these terminally ill patients.  相似文献   
62.
The fructose-1,6-bisphosphate aldolase gene of Drosophila melanogaster contains three divergent copies of an evolutionarily conserved 3' exon. Two mRNAs encoding aldolase contain three exons and differ only in the poly(A) site. The first exon is small and noncoding. The second encodes the first 332 amino acids, which form the catalytic domain, and is homologous to exons 2 through 8 of vertebrates. The third exon encodes the last 29 amino acids, thought to control substrate specificity, and is homologous to vertebrate exon 9. A third mRNA substitutes a different 3' exon (4a) for exon 3 and encodes a protein very similar to aldolase. A fourth mRNA begins at a different promoter and shares the second exon with the aldolase messages. However, two exons, 3a and 4a, together substitute for exon 3. Like exon 4a, exon 3a is homologous to terminal aldolase exons. The exon 3a-4a junction is such that exon 4a would be translated in a frame different from that which would produce a protein with similarity to aldolase. The putative proteins encoded by the third and fourth mRNAs are likely to be aldolases with altered substrate specificities, illustrating alternate use of duplicated and diverged exons as an evolutionary mechanism for adaptation of enzymatic activities.  相似文献   
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64.
A case of anisakiasis causing intestinal obstruction   总被引:1,自引:0,他引:1  
A 31-year old salesman living in Seoul developed suddenly abdominal pain due to intestinal obstruction. Exploratory laparotomy exhibited segmental jejunal cellulitis caused by penetrating Anisakis larva. The patient had eaten raw fish. The typical history of intestinal anisakiasis was presented with a short review of Korean patients of anisakiasis.  相似文献   
65.
66.
A single-stage two-flap method of total ear reconstruction   总被引:2,自引:0,他引:2  
A single-stage two-flap method of total ear reconstruction in congenital microtia is reported. This method was derived from the one-stage reconstruction described by Song and Song. Two flaps defined by vascular basis were elevated on the mastoid area: the superficial skin flap supplied mainly by subcutaneous pedicled arteriole perforators from the posterior auricular artery and the deeper axial-pattern fascial flap including the posterior auricular artery itself. The ear framework, exaggeratedly carved using autologous rib cartilage, could be inserted easily between the two flaps, simultaneously producing the auriculocephalic angle and the conchal wall. Intraoperative expansion of the skin flap and postoperative external ear molding also were performed to create aesthetically pleasing ears.  相似文献   
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68.
We have expressed human tissue plasminogen activator (t-PA) gene at high levels in a mouse cell line. The t-PA cDNA with deletion of the long 3' untranslated region was inserted into a bovine papilloma virus (BPV) derived vector under the control of a mouse metallothionein promoter. The mouse metallothionein (mMT) gene also provided signals for splicing and polyadenylation. Mouse C127 cells transfected with this construct secreted t-PA at high levels into the cell culture medium. When an SV40 polyadenylation signal was inserted between the t-PA cDNA and the mMT splicing signals, the expression level increased by several fold. The expression levels did not increase further upon either introduction of Rous sarcoma virus LTR into the plasmid or mutation of the translation initiation context sequence to conform with the consensus one. Most of the plasmid appears to be integrated into the host chromosome. Cells producing high levels of t-PA tend to detach from the dish in a few days after passage. When grown on porous microcarriers, however, such cells can be maintained in culture for months and t-PA can be harvested continuously.  相似文献   
69.
Cytotoxicity of T-2 toxin, HT-2 toxin, acetyl T-2, neosolaniol, and T-2 tetraol was compared between normal human fibroblasts and mutant I-cell human fibroblasts, which only produce 10 to 15% of lysosomal hydrolases present in normal fibroblasts. Both cleavage of 3-(4, 5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and cell count by hemocytometer were used for evaluations. For all toxins, dose-related effects on both types of cultures were evident. Cytotoxicity of the above mycotoxins on both cell lines were similar, indicating that lysosomal enzymes were not involved in the toxicity of T-2 toxin and its congeners. An inhibitor of lysosomal cysteine proteases (E-64) did not alter the cytotoxicity of T-2 toxin. The decreasing order of toxicity was T-2 toxin, HT-2 toxin, neosolaniol, acetyl T-2 toxin, and T-2 tetraol in both cell lines. When normal human fibroblasts were loaded with the fluorescent dye Lucifer yellow CH (LY), a subsequent treatment of T-2 toxin did not disrupt lysosomal membranes. The uptake of LY was not affected by T-2 toxin, which indicated that T-2 toxin did not interfere with the endocytic pathway. Results indicate that T-2 toxin and its congeners do not exert their primary toxic effect through lysosomal enzymes, membranes, or via the endocytic pathway.  相似文献   
70.
A variety of data support the existence of an opioid receptor complex composed of distinct but interacting mu cx and delta cx binding sites, where "cx" indicates "in the complex." The ability of subantinociceptive doses of [Leu5]enkephalin and [Met5]enkephalin to potentiate and attenuate morphine-induced antinociception, respectively, is thought to be mediated via their binding to the delta cx binding site. [D-Pen2,D-Pen5]Enkephalin also modulates morphine-induced antinociception, but has very low affinity for the delta cx binding site in vitro. In the present study, membranes were depleted of their delta ncx binding sites by pretreatment with the site-directed acylating agent, (3S,4S)-(+)-trans-N-[1-[2-(4-isothiocyanato)phenyl)-ethyl]-3-methy l-4- piperidyl]-N-phenylpropaneamide hydrochloride, which permits selective labeling of the delta cx binding site with [3H][D-Ala2,D-Leu5]enkephalin. The major findings of this study are that with this preparation of rat brain membranes: a) there are striking differences between the delta cx and mu binding sites; and b) both [D-Pen2,D-Pen5]enkephalin and [D-Pen2,L-Pen5]enkephalin exhibit high affinity for the delta cx binding site.  相似文献   
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