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991.
Fatty acid synthetase purified from the mammary gland of the rabbit has a mol. wt. of 968000 as determined by gel filtration. The enzyme gave one band, corresponding to a mol.wt. of approx. 35000, on polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate and phenylmethanesulphonyl fluoride.  相似文献   
992.
3-Deacetoxy-7-(alpha-amino-1-cyclohexenylacetoamido) cephalosporanic acid (SCE-100) was compared to cephalexin with respect to absorption, tissue distribution, and urinary and biliary excretion in mice, rats, rabbits and dogs. The absorption of SCE-100 after oral administration is generally slower than that of cephalexin, but its disappearance from blood and tissues is delayed. The concentration of SCE-100 in the liver is distinctly higher than that of cephalexin. These properties of SCE-100 are most clearly manifested in rats. There is no significant difference in urinary excretion of the two cephalosporins in rabbits and dogs, while in rabbits, biliary excretion of SCE-100 is more intensive than that of cephalexin.  相似文献   
993.
The first case of celiac artery obstruction due to selective arteriography is reported. Impairment of flow to liver and duodenum was present; but the patient recovered uneventfully with non-operative treatment. Management of this problem centers around observation, liver support, and putting the gut at rest. If non-operative treatment is failing, operation should be done, vascular reconstruction carried out, and the duodenum inspected to ensure its viability.  相似文献   
994.
The charts of 311 patients receiving theophylline (T) and 289 patients receiving ipratropium bromide (IB) for COPD were reviewed to determine the total costs and cost-effectiveness of these 2 agents in 3 different health-care settings. A direct cost-accounting method assessed cost, and a Markov decision-analysis model calculated cost-effectiveness. Costs to treat toxic effects were greater for T versus IB. The types and incidences of toxic effects, by drug, were similar among the three centers. Overall costs for T were $121.40 per patient per therapy-month versus $84.56 per patient per therapy-month for IB, as determined by the cost-accounting method. The marginal cost was $366 for T over IB when extrapolated over 1 year using the Markov model. The Markov model also predicted that patients receiving IB had a greater number of complication-free therapy-months (measurement of effectiveness) than patients receiving T. We conclude that treatment with IB was less costly and more cost-effective than T.  相似文献   
995.
996.
A novel 2?4 PSK differential demodulator based on a three-port SAW delay line is described. A method for optimising the performance by tuning the carrier frequency using the DC output of the demodulator is outlined. The optimum performance of the demodulator was within 0.4 dB of theory for a bit error ratio of 10?3.  相似文献   
997.
The propagation of waves of small amplitude at the interface between an elastic half-space and a fluid half-space is investigated. The effects of an explosive line-source embedded in the elastic medium are studied, consideration being given to both dilatational and distortional cases, and a similar investigation is made for a compressive line-source in the fluid. The exact solutions for the displacement field are obtained. It is shown that for fluids of relatively low density, the interfacial waves are of two kinds. The relative efficiencies of the three sources for the launching of these waves are shown explicitly.  相似文献   
998.
A cocci-filament association was discovered in bacterial cultural studies of a subgingival plaque sample. Components were isolated and identified as Veillonella parvula and Eubacterium saburreum. A E. saburreum cell-associated material consisting of approximately 25% glucose and 70% protein was found which may play a role in the adherence of V. parvula to this filament. Acid end product analysis via gas liquid chromatography showed an uptake of lactic and succinic acids by V. parvula resulting in increased levels of acetic, propionic and n-butyric acids in mixed culture of the E. saburreum and the V. parvula strains. The ability of E. saburreum to adhere to nichrome wire and to glass surfaces as well as the secondary plaque forming ability of V. parvula indicates that these organisms may play a role in the maturation of human dental plaque.  相似文献   
999.
1000.
The importance of extrapyramidal and mesolimbic function for circling behaviour was investigated by placing 6-hydroxydopamine (6-OHDA) and electrolesions in the cell bodies, axons and terminals of each system. Circling behaviour was weak when 6-OHDA was placed at the centre of the substantia nigra (SN), but the characteristic contralateral/ipsilateral turning to apomorphine/amphetamine were recorded. Circling was more marked when 6-OHDA was placed anterior to the SN but was generally absent following injections posterior to the SN. However, 6-OHDA placed in the medial forebrain bundle in the lateral hypothalamus resulted in intense contralateral/ipsilateral turning to apomorphine/amphetamine. Generally, the intensity of circling responses was related to the degree of striatal dopamine (DA) depletion but the more effective lesions also caused reductions in mesolimbic DA content. However, circling was not observed following any 6-OHDA injection into the mesolimbic DA system and it is concluded that mesolimbic DA function is not essential for the initiation of circling. In contrast to the 6-OHDA lesions, rats circled ipsilateral to both apomorphine and amphetamine when the SN was damaged by electrocoagulation to cause marked depletion of striatal dopamine. Lesser depletions of striatal dopamine after electrocoagulation in different regions of the medial forebrain bundle were associated with a lower intensity of ipsilateral circling to both drugs. In general, the differences between 6-OHDA and electrolesions could not be explained by additional damage to ascending noradrenaline or 5-hydroxytryptamine pathways. Lower doses of apomorphine were effective in the 6-OHDA circling rats, and the ipsilateral striatum of such rats was more sensitive to directly applied DA. Higher doses of apomorphine were required to produce circling after chronic electrolesions which rendered the ipsilateral striatum insensitive to DA. The contralateral circling to apomorphine after 6-OHDA lesions was abolished by chronic but not by acute electrolesion of the SN. It is suggested that electrolesions of the SN cause different effects to 6-OHDA because they destroy neuronal pathways in addition to the dopaminergic nigrostriatal tract. These appear to be required for the expression of circling behaviour caused by stimulation of the denervated striatum. Whereas 6-OHDA lesions result in super-sensitivity of the denervated strital DA receptors, electrolesions may cause a hypo-sensitivity of the same receptor sites.  相似文献   
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