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1.
E Tal  Y Pfeifer  F G Sulman 《Experientia》1976,32(3):326-327
The effect of negative and positive air ionisation on siliconized blood serotonin was studied in vitro. The experiments showed that within 10 min positive ionisation increased serotonin levels in total blood (+40%), plasma (+90%), erythrocytes (+50%) and thrombocytes (+240%). On the other hand, negative ionization (10 min) lowered the serotonin content of total blood (-30%), plasma (-42.5%), erythrocytes (-41.7%) and thrombocytes (-72.3%), thus confirming the 'Krueger Effect' in vitro.  相似文献   

2.
Summary A new synthesis is described of a crystalline 7-methyl-doisynolic acid showing a strong estrogenic activity. This acid is probably identical with the stereoisomer C ofAnner andMiescher. Demethylation of this methoxyacid yields a new doisynolic acid of mp. 113–117° (hemihydrate).

XIII. MitteilungSynthetische Versuche in der Gruppe der östrogenen Hormone; XII. Mitteilung siehe Chem. listy50, 2004 (1956).  相似文献   

3.
Summary The incorporation of leucice-14C into protein in bovine mesenteric arteries was augmented by cyclic GMP (10–3 M) and decreased by cyclic AMP (10–3 M). There was no effect of 5 AMP (10–3 M). The phosphodiesterase inhibiting drugs theophylline (10–3 M) and papaverine (5×10–5 g/ml) both decreased the leucine-14C incorporation.We are indebted to Mrs.Lena Burlin for hear assistance. Finacial support has been provided by the Swedish State Medical Research Council (No. 04X-101X-4498).  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.
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   

6.
Summary The time course of ATPase activity and force has been determined during contraction and relaxation in skinned (hyperpermeable) anterior byssus retractor muscle, ABRM, ofMytilus edulis and compared with corresponding measurements on skinned taenia coli of guinea-pigs. Following a calcium-induced contraction, lowering the [Ca++] to 10–8 M rapidly reduces ATPase activity within 2 min to resting levels while force declines only to about 30–50% of maximal tension within the same time. Thus slow relaxation is due to a catch-like-state which is common to different kinds of smooth muscles and can be reduced with cAMP in ABRM and by Pi in taenia coli.The support by the Deutsche Forschungsgemeinschaft and the excellent technical assistance of Mrs K. Winnikes are gratefully acknowledged.  相似文献   

7.
Summary The placentae of 17 to 19 days pregnant mice respond to subcutaneous serotonin (15 mg/kg) with vascular changes which lead to the death of the fetuses in 3–4 h. Pretreatment of the females withd-lysergic acid derivatives preserves the life of the young. Thus, LSD showed an ED50 of only 30 g/kg, while UML (Deseril®) gave an ED50 of 3.7 g/kg. PML takes an intermediate position. At a 50% efficiency level, UML (Deseril®) antagonises the effect of a 4000 times higher dose of serotonin.  相似文献   

8.
Enterocytes isolated from rat jejunum were tested for the existence of a Cl/HCO 3 exchange, previously evidenced in basolateral membrane vesicles but not in brush border. Cells were found to retain functional integrity and transport capabilities long enough to allow Cl fluxes to be measured. Both efflux and uptake experiments indicate that a Cl/HCO 3 antiport, inhibited by 4,4-diisothiocyanostilbene-2-2-disulfonic acid (DIDS), is functional under resting conditions.  相似文献   

9.
Zusammenfassung Experimente in vitro zeigen, dass unter Überdruck von 200 mm Hg die Hydrolyse von Cholesteropalmitat in den Aorten und im Blutserum von Ratten gehemmt wird: Die Esterifikation von Cholesterin, in Aorten ebenfalls erniedrigt, zeigt im Serum einen deutlichen Anstieg.

The skillful technical asistance of Mrs.J. Malíková andJ. Straková is gratefully acknowledged.  相似文献   

10.
Zusammenfassung Bei Hunger-Ratten, denen vorwiegend Fettsäure als Energiespender gegeben wurde, wird eine erhöhte Toleranz gegen per os eingegebene Glukose während der Behandlung mit der die Fettsäureoxydation hemmenden -Brompalminsäure gefunden. Bei Dosierungen von 25–500 mg/kg. i.p. verursachte -Brompalminsäure eine signifikante Erhöhung der Glukose-Toleranz.

Acknowledgement. The technical help ofE. Breisch was greatly appreciated.  相似文献   

11.
Summary The retention of bone-seeking radioisotopes85Sr and47Ca was about 20% lower in the femur of 6-day-old infant rats artificially fed on milk, milk supplemented with calcium and phosphorus, and milk supplemented with strontium when 6% cellulose type dietary fibre was added to the diet.Acknowledgments. This work was supported by a research grant from the Scientific Research Council of the Socialist Republic of Croatia. The authors wish to thank Mrs M. Buben, E. Herak, and K. Pribi for their technical assistance.  相似文献   

12.
Summary Mouse foetuses were treated by Thalidomide on days 11–12 in order to verify whether the drug would induce blood abnormalities leading to circulatory troubles. About 18% of the treated foetuses showed both severe limb haemorrhages on day 14, and obvious alterations of the nucleated red blood cells of vitelline origin. These blood abnormalities, occurring suddenly during the well-known critical stage of foetal development, could be responsible for circulatory blocks leading to necrosis.  相似文献   

13.
14.
Protein transduction domains (PTDs) are used to enhance cellular uptake of drugs, proteins, polynucleotides or liposomes. In this study, functionalized Antennapedia (Antp, aa 43–-58) and HIV Tat (aa 47–57) peptides were coupled to small unilamellar liposomes via thiol-maleimide linkage. Modified liposomes showed higher uptake into a panel of cell lines including tumor and dendritic cells than unmodified control liposomes. Liposome uptake was time and concentration dependent as analyzed by flow cytometry and live-cell microscopy. At least 100 PTD molecules per small unilamellar liposome (100 ± 30 nm) were necessary for efficient translocation into cells. Cellular uptake of PTD-modified liposomes was 15- to 25-fold increased compared to unmodified liposomes and was inhibited by preincubation of liposomes with heparin. Glycosaminoglycan-deficient CHO cells showed dramatically reduced cell association of PTD-modified liposomes, confirming the important role of heparan sulfate proteoglycans in PTD-mediated uptake. Antp-liposomes used as carriers of the cytotoxic drug N4-octadecyl-1--D-arabinofuranosylcytosine-(5- 5)-3-C-ethinylcytidine showed a reduction of the IC50 by 70% on B16F1 melanoma cells compared with unmodified liposomes. PTD-functionalized liposomes, particularly Antp-liposomes, represent an interesting novel carrier system for enhanced cell-specific delivery of a large variety of liposome-entrapped molecules.Received 16 April 2004; received after revision 13 May 2004; accepted 25 May 2004  相似文献   

15.
Zusammenfassung Nachweis unterschiedlicher Kontraktionsgeschwindigkeiten bei schnellen und langsamen Kaninchenmuskeln sowie entsprechende Unterschiede in der Myosin-ATPase-Aktivität und im Spektrum niedermolekularer Proteine nach Denervation werden gezeigt.

We are indepted to MissA. Krejová and Mrs.A. Herbrychová for their valuable and skillfull technical assistance.  相似文献   

16.
Zusammenfassung Es wird gezeigt, dass die Natriumund Wasserausscheidung hypophysektomierter Ratten durch ein Hypophysenhinterlappenextrakt korrigiert werden kann. Es handelt sich dabei nicht um ADH und das natriuretische Prinzip scheint auch vom Oxytozin verschieden zu sein.

The present results and conclusions were discussed in detail by one of the authors (B. L.) in his Purkynje Lecture on Interaction of hormonal and non-hormonal mechanisms of the body fluids volume regulation at the XIXth Meeting of the Czechoslovak Physiological Society, held in Prague on January 26–28, 1972.

Acknowledgments. We wish to thank Mrs.E. Blaková for her skilled technical assistance.  相似文献   

17.
Summary The steroidal alkaloid solanidine (solanid-5-ene-3-ol, II) which occurs in the potato plantSolanum tuberosum L. has been synthesized from demissidine (5-solanidane-3-ol, I), an alkaloid from the Mexican wild potatoSolanum demissum Lindl. The synthesis involves the following steps: 5-solanidane-3-one, 2,4-dibromo-5-solanidane-3-one, solanid-4-ene-3-one, 3-acetoxy-solanida-3,5-diene, and solanidine (II).

Solanum-Alkaloide. XVII. Mitteilung. — XVI. Mitteilung:K. Schreiber undG. Adam, Exper.17, 490 (1961).  相似文献   

18.
Zusammenfassung Das Alkaloid Hayatidin, aus Wurzeln vonCissampelos pareiras Linn. isoliert, konnte nach Reduktion seines Äthyläthers und Identifikation der Fragmente durch die Darstellung passender Derivate mit protonmagnetischer Resonanz und weiteren Methoden als (+–)-4'-O-Methylbebeerine charakterisiert werden.  相似文献   

19.
Summary Newton solved what was called afterwards for a short time the directKepler problem (le problème direct): given a curve (e.g. an ellipse) and the center of attraction (e.g. the focus), what is the law of this attraction ifKepler's second law holds?The problème inverse (today: the problème direct) was attacked system-atically only later, first byJacob Hermann, then solved completely byJohann Bernoulli in 1710 and followingBernoulli byPierre Varignon. How didBernoulli solve the problem? What method did he use for this purpose and which of his accomplishments do we still follow today?In the second part various questions connected to the first part are dealt with from the point of view, Conflict and Cooperation, suggested byJ. van Maanen to the participants of the Groningen conference.  相似文献   

20.
Summary Serum peptides containing classical anaphylatoxin (CAT) produce marked chemotactic orientation of human neutrophil granulocytes without modifying cell attachment to the substratum. Furthermore gradients of adhesion produced with gammaglobulins fail to induce morphological orientation of neutrophils. The results suggest that chemotaxis is not a special case of haptotaxis.The excellent technical assistance of Miss M. Schuster, Mrs A. Damschen and Mr M. Arnold is gratefully acknowledged. This work was supported by the Swiss National Science Foundation and the Sandoz-Stiftung zur Förderung der Medizinisch-Biologischen Forschung.  相似文献   

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