DNA synthesis and mitoses in atrial myocytes of rats with aortal stenosis

, . 2- , 1,60 ±0,59% , 0,96 ± 0,44% — . ë . , ³- .     

Mutual replaceability of amide and ester groups in biologically active peptides and depsipeptides

, .     

The effect of chloramphenicol analogs on protein biosynthesis in a cell-freeEscherichia coli B system

a aaa a aa aa a a E. coli aa, a aa aa a , a a aa - a .

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Laboratory of Biological Investigations.

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Laboratory for Chemistry of Antibiotics.     

Antihypertensive effect of Co-factors of the synthesis and precursors of nucleic acids in experimental hypertension

, ₁₂, .     

Mass spectrometric determination of the amino acid sequence in arginine-containing peptides

aa, a-a a- a aa - aa a -a .     

Chromosomes and giemsa-bands of the Idaho spotted ground squirrel,Spermophilus brunneus (Howell)

-Spermophilus brunneus . , 13 18 ,S. brunneus S. townsendii mollis (2n=38) , , ; ;S. brunneus . S. brunneus , Spermophilus.

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Supported by National Science Foundation Grants No. GB32114X and No. GB 29131X, and the Sprague Foundation. We thankD. Pozin for technical assistance.     

A new synthetic method of coumestan derivatives

Zusammenfassung Die Synthese von 7-Hydroxy-5,6-dimethoxybenzofurano[3,2:3,4]coumarin aus 7,2-Dihydroxy-oder 7-Benzyloxy-2-hydroxy-4,5-dimethoxyisoflavon wird beschrieben.     

X-ray research of polycrystals. X-ray diffraction methods for precision determinations of polycrystal lattice parameters over unsolved double lines

. - .     

Extrapyramidal pathways with monosynaptic effects upon primate α-motoneurons

, , , , , -.     

Artificial lung ventilation during diaphragmatic paralysis

ÿe , CO₂ . CO₂ ÿe . , ÿe , .     

Hydra vulgaris ω10-lipoxygenase is used in vivo to synthesize new α-linolenic acid metabolites

Previous studies conducted in cytosolic extracts of the freshwater hydrozoanHydra vulgaris led to the finding of an abundant 11(R)-lipoxygenase catalyzing the peroxidation of polyunsaturated fatty acid (PUFAs) on the tenth carbon atom from the aliphatic end (10 peroxidation). Here we describe experiments aimed at identifying the actual metabolites generated in vivo by such enzymic activity. Homogenates ofH. vulgaris polyps were analyzed by HPLC. This showed the presence of three major components chromatographically identical to three metabolites obtained when incubating the homogenates with exogenous -linolenic acid (-LA). The presence, in extracts of polyps prelabelled with [¹⁴C]--linolenic acid, of radioactive metabolites displaying the same chromatographic properties, substantiated the hypothesis that the natural products isolated in vivo are derived from -LA. Gas chromatographic analyses revealed that this was the most abundant PUFA in both free and phosphoglyceride-bound fatty acid pools. [¹H]-NMR analysis of the endogenous substances, carried out in comparison with products obtained from exogenously incubated -LA, indicated that their structures were those of 9-hydroxy-, 9-hydroperoxy- and 9-keto-octadeca-10E-12Z-15Z-trienoic acids (9--HOTrE,-HPOTrE and-KOTrE).Hydra homogenates transformed 9--HPOTrE partly into 9--HOTrE and partly into 9--KOTrE. Chiral phase HPLC conducted on 9--HOTrE established that this metabolite was composed mostly of theR anantiomer. These observations, and the finding that the presence of exogenous arachidonic acid in incubated homogenates significantly reduces the production of -LA metabolites, provide strong evidence that these compounds are produced by an enzymic activity identical to the previously-describedH. vulgaris (R)-10-lipoxygenase. Further experiments suggested that -LA, acting as the native substrate for this enzyme, is mainly esterified on the 2 position ofHydra phosphoglycerides, and that the production of the -LA metabolites described here for the first time from natural sources, can be potentially enhanced in vivo by stimuli activating phospholipase A₂.     

G-band patterns as chromosomal markers,and the interpretation of chromosomal evolution in wild sheep (Ovis)

- . Ovis musimon (2n=54) O. orientalis (2n=54) - - -O. canadensis mexicana (2n=54) O. musimon x O. canadensis ₁₂ - . ₂ 27 . - .

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Supported by National Science Foundation Grant no. GB 32114X and the Sprague Foundation. We thank Dr. T. C. Hsu for assistance in making the chromosome preparations and for advice and encouragement. The Trustees of the Rachelwood Wildlife Research Preserve generously allowed the biopsy of specimens of their custody. Mr.Arthur Popham kindly provided the specimens from Iran while Dr.R. M. Robinson obtained biopsies from the desert sheep.     

Proteins of venezuelan equine encephalomyelitis virions

. : (. . 59,000–61,000 ), (34,000–38,000) (15,000–18,000).     

The peculiarities of capacitance vessel reflex responses

Conclusion Changes of the vessel capacity resulted from the pressor synocarotid reflexes, intestinal chemoreflexes and reflexes from the right atrium or ventricle and electric stimulation of the somatic nerve afferents can be either similarly or differently directed as compared with the responses of the resistance vessels.

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, , , .

     

Über die Brenzkatechinamine im Froschherzen und in der Froschhaut vor und nach Verabfolgung von α-Methyldopa

Summary (1) The adrenalin of the frog heart was found to be localized mainly in the granular fraction (100,000g). After pretreatment with -methyldopa (-MD), the heart also contained -methyldopamine, -methylnoradrenalin, and -methyladrenalin. (2) -MD caused a maximal expansion of the melanophores. This action was counteracted byl-dopa, which per se caused a contraction of the melanophores. After pretreatment with -MD the skin contained besides adrenalin also -methyldopamine and -methyladrenalin. In addition also 5-hydroxytryptophan expanded the melanophores.     

Topochemical approach to the structure-activity relation. Retroenantio-Gly5,10-gramicidin S

, . , -Gly^5,10- , Gly^5,10- .     

A study of the mechanism of polymyxin M inactivation

.I.NH₄OH , N N - - ,-. , .     

Studies on rII region of T2L phage

rII T2L , rII T4B. rII T2L rII T4B. T2L rII T4B.     

Separation of rat liver mitochondrial amine oxidases

.     

Magnug reflexex of the chest musculature in man

, , .