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1.
Summary The-d-fucosidase and -l-fucosidase activities of digestive juice ofHelix pomatia have been studied.-d-fucosidase can be separated from-d-galactosidase by heat inactivation.  相似文献   

2.
a aaa a aa aa a a E. coli aa, a aa aa a , a a aa - a .

Laboratory of Biological Investigations.

Laboratory for Chemistry of Antibiotics.  相似文献   

3.
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.  相似文献   

4.
Summary The new methods for the production of 19-norsteroids described involve the conversion of 5-halogen-6-hydroxy-steroids into the corresponding 5-halogen-6:19-ethers either with lead tetraacetate or by the hypoiodite reaction8,10. The 6:19-oxygen bridge is then opened reductively either directly or after oxidation of the 6:19-ethers to lactones or preferably after introduction of a 4,6-3-oxo grouping. Acylolytic cleavage of the 4-3-oxo-6:19-ethers followed by alkaline hydrolysis gives 4,6-3-oxo-19-hydroxy-steroids. The 19-hydroxycompounds formed are easily converted into 19-norsteroids by known methods.

Über Steroide, 189. (vorläufige) Mitteilung; 188. Mitt. vgl.J. Kalvoda, J. Schmidlin, G. Anner undA. Wettstein, Exper.18, 398 (1962).  相似文献   

5.
- . Ovis musimon (2n=54) O. orientalis (2n=54) - - -O. canadensis mexicana (2n=54) O. musimon x O. canadensis 12 - . 2 27 . - .

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.  相似文献   

6.
Summary Starting from 17-hydroxy-17-hydroxymethyl-4-androsten-3-one, we synthesized 4-chloro-17-hydroxy-17-hydroxymethyl-4-androsten-3-one-17, 20-acetonide and 17-hydroxy-17-hydroxymethyl-1, 4-androstadien-3-one. 11, 17-dihydroxy-17-hydroxymethyl-4-androsten-3-one was obtained from cortisone via methyl-17-hydroxy-3, 11-dioxo-4-etienate.  相似文献   

7.
8.
Summary Tritium distribution on randomly labelled taurocholate (TC) was estimated at 28%, 4%, 1% and <0.5% on the hydrogens opposite the 3-, 7- and 12-OH groups and taurine moiety respectively. Anomalously,C. perfringens 3-hydroxysteroid dehydrogenase (3-HSDH) catalyzed tritium loss of 36% on formation of 7-, 12-dihydroxy-3-keto-5-cholanoate, implying additional losses of tritium at other sites by this enzyme.This work is supported by the National Cancer Institute.  相似文献   

9.
Defensive steroids from a carrion beetle (Silpha americana)   总被引:2,自引:0,他引:2  
Summary The defensive anal effluent discharged bySilpha americana in response to disturbance contains a mixture of steroids stemming from a glandular annex of the rectum. The compounds have been characterized as 15-hydroxyprogesterone (1, principal component), 5-pregnan-15-ol-3, 20-dione (2), 5-pregnan-3, 15-diol-20-one (3), 5-pregnan-7, 15-diol-3,20-dione (4), 5-pregnan-3, 7, 15-triol-20-one (5), 5-pregnan-16-ol-3,20-dione (6), and 5-pregnan-3, 16-diol-20-one (7), none previously found in insects. Bioassays with jumping spiders showed compounds1 and6 to be feeding deterrents at the 1 g level.Paper No. 78 of the series: Defense Mechanisms of Arthropods. Study supported by NIH (Grants AI-02908, AI-12020). We thank Maura Malarcher and Maria Eisner for excellent technical help, and the Squibb Institute of Medical Research for samples of authentic reference compounds.  相似文献   

10.
Zusammenfassung Die Injektion von N6-2-O-Dibutyryl-adenosin-3 5-monophosphat in den lateralen Hirnventrikel von Kaninchen führt zu einer langanhaltenden Fieberreaktion, was vermuten lässt, dass zyklisches Adenosin-35-monophosphat als weiterer Mediator in der Genese des Fiebers fungiert.  相似文献   

11.
Zusammenfassung Nach. i.v. Gabe von 7-3H-Dehydroepiandrosteron wurde menschliches Plasma einer präparativen Zonenelektrophorese unterworfen und in Albumine, 1-, 2-,- und-Globuline zerlegt. Aus den einzelnen Proteinfraktionen trennte man freie Steroide, Steroid-Sulfokonjugate und -Glukuronoside ab und untersuchte letztere Fraktionen auf ihren Gehalt an markierten C19-Steroiden. Es zeigte sich, dass die Steroid-Sulfokonjugate vornehmlich in der Proteinfraktion der Albumine, die Steroid-Glukuronoside dagegen bevorzugt in der Proteinfraktion der 1-Globuline auftraten.  相似文献   

12.
13.
A new radioimmunoassay has been developed for thymosin 4 by generating rabbit polyclonal antibodies against the synthetic N-terminal peptide fragment 1–15 coupled to KLH. The synthetic analogue [Tyr12]-thymosin 4 (1–15) was used as tracer. This radioimmunoassay, with a useful range of 10–1000 pmoles, showed cross-reactivity with the second homologous -thymosin of man and rat (thymosin 10) but not of calf (thymosin 9). This radioimmunoassay, together with an improved radioimmunoassay for the N-terminus of parathymosin , was employed for the measurement of the levels of thymosin 4 and parathymosin in nuclear and extranuclear extracts of calf thymus. The bulk of these polypeptides was found in the extranuclear material whereas only traces were observed in the nuclear environment, which indicates the extranuclear localisation of - and -thymosins.  相似文献   

14.
15.
Summary [1-N4-Dimethyl-asparagine]-angiotensin II was synthesized by Merrifield's solid-phase procedure. The analogue gave rat blood pressure about 70% relative potency to Hypertensin (Ciba). Rabbit aorta strips gave intrinsic activity E=1, a PD2 of 6.92±0.09 and an affinity relative to [Asn1]-angiotensin II of 6.5%.The editors do not hold themselves responsible for the opinions expressed in the authors' brief reports. — Les auteurs sont seuls responsables des opinions exprimées dans ces brèves communications. — Für die Kurzmitteilungen ist ausschliesslich der Autor verantwortlich. — Per le brevi comunicazioni è responsabile solo l'autore. — . — Solo los autores son responsables de las opiniones expresadas en estas comunicationes breves.Acknowledgment. The authors wish to express their appreciation to Dr Emanuel Escher, School of Medicine, Centre Hospitalier Universitaire, Sherbrooke, Quebec, for his help in providing the biological data and critical comments.  相似文献   

16.
Zusammenfassung Es wird über die Herstellung des 16-Methylprednisons berichtet, welche vom Hecogenin ausgehend über ca. 15 Stufen durchgeführt wird. Als wichtige Zwischenstufe treten 5-Pregn-16-en-3-ol-11, 20-dion-Acetat und 16-Methylen-5-pregnan-3, 17-diol-11, 20-dion auf: letzteres wird durch eine stereospezifische katalytische Reduktion in das entsprechende 16-Methyl-derivat umgewandelt.  相似文献   

17.
Summary In vitro, the mixture Chlorpromazine-human serum gives modifications of the lipoproteins and the-globulins. These modifications are studied by paper electrophoresis, Tiselius-electrophoresis, and immuno-electrophoresis. Under the experimental conditions described, the selective precipitation of the 1-globulins seems quite unexpected.  相似文献   

18.
Summary The octapeptide Val5-Angiotensin II-Asp1--amide is split into characteristic fragments by hydrogen peroxide, when complexed with Ni2+; this degradation does not occur with the Cu2+ complex, presumably because an active ternary peroxo complex cannot be formed.  相似文献   

19.
Zusammenfassung (1) Es wird die DNS-Synthese der letalen SeeigelbastardeParacentrotus ×Arbacia (PA) undParacentrotus ×Sphaerechinus (PS) mit H3-Thymidin untersucht. (2) Dem verschiedenen, der Letalität vorausgehenden Entwicklungstpus (PA ohne, PS mit Chromosomenelimination) entspricht ein verschiedener Verlauf der Hemmung der DNS-Synthese. Parallel dazu wird die Vermehrung in der Anzahl der Kerne verglichen.  相似文献   

20.
Summary In this note we claim that the two words and , which were used in Greece to indicate the geometrical point, had both been introduced in the scientific language in the first half of the IVth century B.C., and that they became popular independently of each other in two different cultural circles, those of philosophy and of mathematics, respectively.We propose therefore, in contrast to a conjecture by Heiberg, a new explanation for the predominance of during the golden age of Greek mathematics and for the resurgence of during the period of decadence.

Memoria presentata da A. Seidenberg  相似文献   

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