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51.
Anatomic correction of transposition of the great vessels 总被引:1,自引:0,他引:1
AD Jatene VF Fontes PP Paulista LC Souza F Neger M Galantier JE Sousa 《Canadian Metallurgical Quarterly》1976,72(3):364-370
We present a new approach for anatomic correction of transposition of the great arteries. The two coronary arteries, with a piece of the aortic wall attached, are transposed to the posterior artery. The two aortic openings are closed with a patch. The aorta and pulmonary artery are transected, contraposed, ant then anastomosed. The interventricular septal defect is closed with a patch, through a right ventriculotomy approach, because the right ventricle is no longer part of the systemic circulation. Two patients, aged 3 months and 40 days weighing 4,200 and 3,700 grams, respectively, were operated upon with deep hypothermia and total circulatory arrest. There was good recovery from the operation, with normal cardiocirculatory conditions. Renal failure developed in the first patient, and she died on the third postoperative day. During this time the cardiocirculatory conditions were good. The second patient made an uneventful recovery. Hemodynamic studies 20 days after the operation showed complete correction of the malformation. Five and one-half months after the operation, he weighs 7,500 grams, and his development is very good. We believe that this operation will be reproducible by most cardiovascular septal defect and pulmonary hypertension. 相似文献
52.
This report is concerned mainly with the properties of an enzyme from rat liver microsomes which hydrolyzes the alkenyl ether
bond of 1-(1′-alk-1′-enyl)-glycero-3-phosphoryl-choline (alkenyl-GPC hydrolase).
Destruction of the normal environment of the microsomes by treatment with phospholipases A or C caused inactivation of the
alkenyl-GPC hydrolase, which was then partially reactivated by the addition of exogenous phospholipids. Both sphingomyelin
and diacyl-GPC were efficient in restoring activity; diacyl-GPE was less effective; and monoacyl-GPC and monoacyl-GPE were
ineffective. The presence of two long hydrocarbon chains in the lipid activator is apparently required for reactivation, suggesting
that interaction of hydrophobic areas of the enzyme with the phospholipid is necessary for maximal activity. High concentrations
of sucrose mimicked the effect of phospholipids, and because the sucrose and diacyl-GPC did not show an additive effect, they
may reactivate the enzyme in a similar manner.
Disrupting the enzyme's environment by freezing and thawing the preparation also resulted in a loss of enzymatic activity,
which was restored by added exogenous phospholipids.
The alkenyl-GPC hydrolase was inhibited by imidazole and some of its derivatives. Histidine and N-acetyl histidine did not
inhibit the enzyme, presumably due to the presence of a negative charge on the carboxyl group rather than the steric bulk
of that group, since histidine methyl ester did inhibit the enzyme. Kinetic evidence showed imidazole to be a competitive
inhibitor. The enzymatic activity of imidazole-treated microsomes also increased following addition of exogenous phospholipids.
Imidazole inhibition differed from the phospholipase A-inactivation in that it was partially reversed by KCl, but not by sucrose.
Imidazole did not inhibit other microsomal enzymes tested, indicating that it is not a general inhibitor of membrane-associated
enzymes. 相似文献
53.
Diffusion of an injected sample within a gas chromatographic column does not begin from a point source but from a band. Therefore
the method of calculating relative areas by using retention time × peak height may require a correction factor to give a more
accurate estimate of peak areas. When this correction was applied, the analysis was comparable with that obtained by the more
time-consuming triangulation method. 相似文献
54.
55.
Iron regulatory proteins (IRPs) control the synthesis of several proteins in iron metabolism by binding to iron-responsive elements (IREs), a hairpin structure in the untranslated region (UTR) of corresponding mRNAs. Binding of IRPs to IREs in the 5' UTR inhibits translation of ferritin heavy and light chain, erythroid aminolevulinic acid synthase, mitochondrial aconitase, and Drosophila succinate dehydrogenase b, whereas IRP binding to IREs in the 3' UTR of transferrin receptor mRNA prolongs mRNA half-life. To identify new targets of IRPs, we devised a method to enrich IRE-containing mRNAs by using recombinant IRP-1 as an affinity matrix. A cDNA library established from enriched mRNA was screened by an RNA-protein band shift assay. This revealed a novel IRE-like sequence in the 3' UTR of a liver-specific mouse mRNA. The newly identified cDNA codes for a protein with high homology to plant glycolate oxidase (GOX). Recombinant protein expressed in bacteria displayed enzymatic GOX activity. Therefore, this cDNA represents the first vertebrate GOX homologue. The IRE-like sequence in mouse GOX exhibited strong binding to IRPs at room temperature. However, it differs from functional IREs by a mismatch in the middle of its upper stem and did not confer iron-dependent regulation in cells. 相似文献
56.
57.
LC Pronk WL van Putten V van Beurden M de Boer-Dennert G Stoter J Verweij 《Canadian Metallurgical Quarterly》1999,43(2):173-177
PURPOSE: Fluid retention, which includes peripheral edema, ascites, pleural or pericardial effusion, or a combination of these that is sometimes associated with significant weight gain, is one of the most troublesome cumulative side effects of docetaxel. A suggestive observation from the data base available at the manufacturer (Rhone-Poulenc Rorer) was that patients who received venotonic drugs appeared to tolerate more courses of docetaxel. This prompted a comparative study to investigate whether the venotonic drug hydroxyethylrutosiden could reduce or delay docetaxel-related fluid retention. METHODS: A total of 85 patients with metastatic breast cancer who were treated with docetaxel at a dose of 100 mg/m2 with corticoid comedication were allocated to receive either 300 mg hydroxyethylrutosiden given orally four times daily (group A) or no hydroxyethylrutosiden (group B). The end point for analysis was the development of fluid retention of > or = grade 2. RESULTS: Fluid retention of > or = grade 2 was reported in 14 of 42 patients (33%) in group A and in 15 of 43 patients (35%) in group B and occurred after a median of 4 cycles of docetaxel in both groups. Weight gain was similar in groups A and B. CONCLUSION: We conclude that hydroxyethylrutosiden does not reduce or delay the incidence and severity of docetaxel-related fluid retention. 相似文献
58.
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60.
Initial experiments using whole cells have shown that there were specific and saturable interactions between kunjin (KUN) virus and receptor molecules on the Vero cell surfaces. Solubilisation of Vero cell plasma membranes with octyl-D-glucoside (OG) yielded an extract which also interacted specifically with KUN virus. This was proven using electron microscopy. When the virus-OG-extract complex was exposed onto Vero cell monolayers, no KUN virus was observed to enter into the whole cells. This would imply that there was virus-receptor interaction with the OG-extract leaving no free virus to attach to the whole cells. The attachment kinetics of KUN virus was studied further using the Scatchard analysis which indicated the involvement of more than one interactive macromolecule in the attachment event. 相似文献