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991.
992.
Custom prefabrication of free flaps provides an unlimited variety of applications, since flaps can be created with expendable tissues and without restriction to naturally occurring vascular territories. These principles also can be used to customize flaps that could not be completed by conventional means. We report a case of scalp reconstruction using a random-pattern abdominal flap in which a radial artery fascial flap was induced to serve as the vascular carrier. In addition to providing durable scalp coverage, the prefabricated free flap enabled salvage of an abdominal flap that would otherwise have been aborted after intermediate transfer to the forearm.  相似文献   
993.
994.
995.
Results of the study of taurine and dipeptide Tyr-Tyr effect on the threshold values of functional lesions of the myocardium and heart defibrillation are reported. The experiments were carried out on 27 narcotized mongrel dogs weighing 12-30 kg. Defibrillation was performed using Lifepak-7 defibrillator (USA). Lesion threshold (LT), defibrillation threshold (DT) and electrotherapeutic index (ETI) as a LT:DT ratio were determined. In 14 experiments (control group) these parameters were evaluated during 3 h. In group 1 (6 experiments) taurine (100 mg/kg) was infused intravenously by the end of the 1st hour, in group 2--Tyr-Tyr (25 mg/kg). It was shown that infusion of taurine did not have a noticeable effect of the LT, DT and ETI values. Infusion of Tyr-Tyr resulted in an increase in LT and DT. The possibility to use dipeptide Tyr-Tyr in the complex of measures aimed at ceasing ventricular fibrillation is discussed.  相似文献   
996.
We report the molecular cloning of a fragment of human genomic DNA called S12, containing an open reading frame of 1170 nucleotides, which encodes a receptor for serotonin of 390 amino acids. The receptor function of the S12 protein was demonstrated by functional expression in mouse LS12 cells obtained by stable transfection of Ltk- cells, and LM5S12 cells, derived from LM5 cells (Ltk- cells previously transfected with the M5 muscarinic acetylcholine receptor). Adenylyl cyclase studies showed that the S12 receptor is able to mediate inhibition of adenylyl cyclase in response to serotonin in both types of cells. As studied in LM5S12 cells, the S12 receptor did not promote Ca2+ mobilization from internal stores, nor did it significantly modulate the sustained increase in [Ca2+]i elicited by stimulation of the phospholipase C stimulating M5 acetylcholine receptor. The pharmacologic profile of S12 as seen in adenylyl cyclase assays is as follows: (EC50 in nM): serotonin, full agonist (37 nM), 5-carboxamidotryptamine, full agonist (10 nM), sumatriptan, full agonist (50 nM), metergoline, partial agonist (10 nM), methysergide, partial agonist (40 nM), yohimbine, partial agonist (150 nM), metitepin, antagonist (KB = 0.7 to 1.2 nM). We propose that the human S12 serotonin receptor is a receptor of the 5-hydroxytryptamine1D subtype.  相似文献   
997.
 The role of the polypeptide matrix in electron transfer processes in proteins has been studied in two distinct systems: first in a protein where the induced ET is artificial, and second as part of the catalytic cycle of an enzyme. Azurins are structurally well-characterized blue single-copper proteins consisting of a rigid β-sheet polypeptide matrix. We have determined rate constants and activation parameters for intramolecular long-range electron transfer between the disulfide radical anions (generated by pulse radiolysis) and the copper(II) centre as a function of driving force and nature of the intervening medium in a large number of wild-type and single-site-mutated proteins. In ascorbate oxidase, for which the three-dimensional structure is equally well characterized, the internal ET from the type-I Cu(I) to the trinuclear Cu(II) centre has been studied. We find that the results correlate well with distance through well-defined pathways using a through-bond electron tunnelling mechanism. Received: 2 January 1997 / Accepted: 6 February 1997  相似文献   
998.
Relationships between the strongyloid nematodesRugopharynx delta, R. zeta, R. omega, R. longibursaris, R. mawsonae andR. sigma, all from macropodid marsupials, were investigated using allozyme data. The phylogenetic trees derived from the electrophoretic data set were congruent with those of the hosts and were consistent with the hypothesis that the species complex originated in pademelons of the genusThylogale and diversified in rock-wallabies (Petrogale spp.) and scrub wallabies of the subgenusNotamacropus. Host switching is evident only between closely related macropodid taxa.  相似文献   
999.
1000.
The effect of intranasal substance P injection on parkinsonian syndrome and the generator of pathologically enhanced excitation (GPEE) in caudate nuclei (CN) was investigated. MPTP or reserpine administration in old rats induced oligokinesia, rigidity and tremor followed by the high amplitude slow and rapid waves in both CN. The bilateral intranasal injection of substance P (25 micrograms/kg) resulted in an increase in motor activity and almost completely abolished the rigidity and tremor. The reduction of extrapyramidal symptoms was considered as a result of the inhibition of GPEE in CN. The possibility of substance P entry from nasal cavity into the brain was discussed. The changes of the substance P balance in nigrostriatal system was suggested to be on of the pathogenetic links of parkinsonian syndrome.  相似文献   
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