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81.
The functional status of the oxidative-antioxidative system was studied in 72 patients after vast cancer operations. Traditional surgical treatment and its combination with intraoperative irradiation were shown to lead to tense antioxidative defense and to suppressed T-cell immunity and to call for antioxidative and immunomodulating therapy. High intraoperative blood loss complicated by hemorrhagic shock injured the oxidative-antioxidative system greatly. The magnitude of this damage correlated with the rate of prehypoxia. Addition of the potent antioxidant Ceruloplasmin to the drug regimen normalized a recovery period, helped to correct posthypoxic multiorgan insufficiency, to recover oxidative-antioxidative balance, and to decrease the incidence of pyoinflammatory complications. Patients with endogenous intoxication showed activated lipid peroxidation, decreased functional activity of antioxidative defense components and of T-cell immunity in homeostasis. The use of Ceruloplasmin and Laprot had pronounced antiinflammatory and detoxifying effects on the patient's body and activated its antioxidative defense.  相似文献   
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The shapes of the motor domains of kinesin and ncd, which move in opposite directions along microtubules, have been investigated. Using proteins expressed in Escherichia coli, it was found that at high salt (> 200 mM) Drosophila ncd motor domain (R335-K700) and human kinesin motor domain (M1-E349) were both sufficiently monomeric to allow an accurate determination of their radii of gyration (Rg) and their molecular weights. The measured Rg values of the ncd and kinesin motor domains in D2O were 2.06 +/- 0.06 and 2.05 +/- 0.04 nm, respectively, and the molecular weights were consistent with those computed from the amino acid compositions. Fitting of the scattering curves to approximately 3.5 nm resolution showed that the ncd and kinesin motor domains can be described adequately by triaxial ellipsoids having half-axes of 1.42 +/- 0.38, 2.24 +/- 0.44, and 3.65 +/- 0.22 nm, and half-axes of 1.52 +/- 0.23, 2.00 +/- 0.25, and 3.73 +/- 0.10 nm, respectively. Both motor domains are described adequately as somewhat flattened prolate ellipsoids with a maximum dimension of approximately 7.5 nm. Thus, it appears that the overall shapes of these motor domains are not the major determinants of the directionality of their movement along microtubules.  相似文献   
84.
Conditions have been established for H4IIE rat hepatoma cell cultures in which effects of cytochrome P-450 induction on the metabolism of a munitions wastestream pollutant can be studied. Under these conditions, the polychlorinated hydrocarbon 2,3,4,7,8-pentachlorodibenzfuran (PCDBF) induced cytochrome P-450 (1A1) aryl hydrocarbon hydroxylase (AHH) activity over a wide range of concentrations without significant cytotoxic effects. The munition pollutant 2,4-dinitrotoluene (2,4-DNT) did not induce AHH activity itself, but its metabolism was considerably altered when applied to PCDBF induced cultures. Production of amino nitrotoluene isomers was greatly enhanced in induced cultures as compared to uninduced controls, as was the conversion of radiolabeled 2,4-DNT to relatively more polar metabolites. To some extent, the results with H4IIE cells parallel those reported for animals exposed to 2,4-DNT after induction of cytochrome P-450 AHH activity. The preliminary findings suggest that with further development and validation, H4IIE cultures could be of use in characterizing metabolites that result from exposure to chemical mixtures involving a P-450 (1A1) inducer.  相似文献   
85.
This document represents the recommendations of a panel of Spanish experts on antibiotic use and resistance. In a Task Force, under the auspices of the Spanish Ministry of Health and Consumer Affairs that took place in 1994 in Madrid, the members were gravely concerned about the national increase in antibiotic resistance. They analysed the development, evolution and spread of antibiotic resistance among community-acquired human bacterial pathogens in Spain, its relation with antibiotic consumption, and they proposed future surveillance strategies for monitoring the patterns of antibiotic use and consumption. Success will require a collective action among the producers (pharmaceutical industry), prescribers (doctors, veterinarians), dispensers (pharmacists), and consumers (patients). Two similar documents have been recently published by the American Society of Microbiology and the World Health Organization showing the global concern about this topic.  相似文献   
86.
Animal models of amyotrophic lateral sclerosis (ALS) provide a unique opportunity to study this incurable and fatal human disease both clinically and pathologically. This is particularly true for certain pathological and therapeutic studies that are impractical or impossible to perform in human patients. Nonetheless, postmortem ALS tissue remains the "gold standard" against which pathologic findings in animal models must be compared. Four natural disease models have been most extensively studied, including three mouse models: motor neuron degeneration (Mnd), progressive motor neuronopathy (pmn), wobbler, and one canine model: hereditary canine spinal muscular atrophy (HCSMA). The wobbler mouse has been the most extensively studied of these models with analyses of clinical, pathological (perikaryon, axon, muscle), and biochemical features. Experimentally induced ALS animal models have allowed controlled testing of various neurotoxic, viral and immune-mediated mechanisms. Molecular techniques have recently generated mouse models in which genes relevant to the human disease or motor neuron biology have been manipulated. The most clinically relevant of these is a transgenic mouse overexpressing the mutated SOD1 gene of FALS patients, which has already provided significant insights into mechanisms of motor neuron degeneration in this disease. Because no single animal model perfectly reflects all the clinical and pathological characteristics of ALS, study of selected features from the most relevant models will contribute to a better understanding of the pathogenesis and/or etiology of this disease.  相似文献   
87.
Between 1979 and 1992, the alar folds were resected bilaterally in 22 horses and unilaterally in 2 horses. Abnormal respiratory tract noise and exercise intolerance were the primary complaints prior to surgery. Significantly (P = 0.01) more Standardbreds underwent resection of the alar folds, compared with the number of Standardbreds in the hospital population during the same period. The alar folds palpated abnormally thick in 13 horses and normal in 11 horses. Temporary dilatation of the nares with mattress sutures or clips lessened the respiratory tract noise and improved exercise tolerance in all 8 horses in which the diagnostic test was performed. Manual elevation of the alar folds reduced respiratory noise in the 11 horses evaluated. Long-term follow-up evaluation by telephone was available for 14 horses. All surgical incisions had healed cosmetically. Respiratory tract noise was decreased, and exercise tolerance improved in 10 of 14 (71%) horses. Complete charted racing information was obtained for 16 horses. Fourteen horses started their first race a mean of 118 days (range, 13 to 321 days) after surgery. The mean number of starts after surgery was 51, with 14 of 16 (88%) horses starting more than 6 times after surgery. Of the 16 horses, 8 horses raced at least 3 times before and after surgery; 4 had improved racing performance, 2 had similar performance, and 2 had decreased performance. Five Standardbreds never raced, and 1 Standardbred raced once before surgery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Rats were intraperitoneally injected with neurotropin (NSP), a substrate extracted from the inflammatory dermis of rabbits inoculated with Vaccine virus. Active avoidance behaviour of rats was studied. After NSP administration rats demonstrated higher levels of conditioning and true responses compared with control. In NSP-treated rats relationship between the time of beginning of intersignal run during learning and success of the avoidance trial differed from that in the control group. The results suggest that neurotropin administration activates the retrieval processes and leads to stronger consolidation of avoidance behaviour.  相似文献   
90.
Kinesin is the founding member of a superfamily of microtubule based motor proteins that perform force-generating tasks such as organelle transport and chromosome segregation. It has two identical approximately 960-amino-acid chains containing an amino-terminal globular motor domain, a central alpha-helical region that enables dimer formation through a coiled-coil, and a carboxy-terminal tail domain that binds light chains and possibly an organelle receptor. The kinesin motor domain of approximately 340 amino acids, which can produce movement in vitro, is much smaller than that of myosin (approximately 850 amino acids) and dynein (1,000 amino acids), and is the smallest known molecular motor. Here, we report the crystal structure of the human kinesin motor domain with bound ADP determined to 1.8-A resolution by X-ray crystallography. The motor consists primarily of a single alpha/beta arrowhead-shaped domain with dimensions of 70 x 45 x 45 A. Unexpectedly, it has a striking structural similarity to the core of the catalytic domain of the actin-based motor myosin. Although kinesin and myosin have virtually no amino-acid sequence++ identity, and exhibit distinct enzymatic and motile properties, our results suggest that these two classes of mechanochemical enzymes evolved from a common ancestor and share a similar force-generating strategy.  相似文献   
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