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1.
Summary Effects of - or -D-glucose on the respiration of germinated spores (only germinated spores not including swollen spores and elongated spores) ofBacillus subtilis andB. megaterium were studied. In our conditions, net amount of oxygen consumed by 1010 germinated spores ofB. subtilis per min after addition of - or -D-glucose was 1.6 g or 6.6 g (/=4.13), while that byB. megaterium was 4.5 g or 6.8 g (/=1.51), respectively. However, the net amounts of oxygen consumed by 1010 vegetative cells per min after addition of - or -D-glucose were identical, forB. subtilis in both cases 443.0 g and forB. megaterium in both cases 604.4 g.  相似文献   

2.
Summary The total cerebellar proteins RNA and DNA contents from DLT4- and LT3-treated rats was studied at 6 and 35 days of age. The effect of injections of 5 g/j of DLT4 is comparable to that of 25 g of LT3 at birth, followed by 0.5 g every 2 days. On the other hand, injection of 0.5 g of LT3 every 2 days does not induce any significant modification of the total DNA contents in the cerebellum.  相似文献   

3.
Summary Dopamine topically applied to the cerebral cortex (1–20 g/ml) or administered i.v. (0.5–64 g/kg/min) has no effects on cerebral cortical blood flow in the rat.  相似文献   

4.
Platelet aggregation is inhibited by phycolectins   总被引:2,自引:0,他引:2  
Lectins from four marine algal species were examined for interaction with human platelets. The lectin designated hypnin A, from the red algaHypnea japonica, inhibited adenosine diphosphate (ADP)-or collagen-induced human platelet aggregation in a dose-dependent manner. Complete inhibition was observed at concentrations of 100 and 5 g/ml of the lectin with, ADP (2 M) and collagen (0.2 g/ml)-induced platelet aggregation, respectively. At the inhibitory concentration of 0.5 to 100 g/ml, the lectin did not induce aggregation of resting platelets. Lectins from the other three algal species also inhibited ADP-induced human platelet aggregation. These results indicate that the algal lectins are a new group of inhibitors and may be useful to study glycoconjugates on platelet membranes and to design novel platelet aggregation inhibitors.  相似文献   

5.
Summary Indocyanine green (ICG) obeyed the Beer-Lambert law within the concentration range 1.25 g/ml–10.0g/ml in distilled water, methanol, dimethylformamide (DMF), 1.2-propanediol and aqueous buffers (pH 9.0), but only up to 7.5 g/ml in human bile and 0.5% human albumin, and only to 5.0 g/ml in human duodenal fluid. ICG was rapidly (<1 h) decomposed to a colorless derivative at pH<5 and >11, but remained relatively stable for 48 h at pH 8–10. ICG is an indicator and a weak acid with a pKa of 3.27. In bile stabilized with 25% methanol, the precision of the method (CV) is 5% and the accuracy is 106–127%.  相似文献   

6.
Summary The influence of somatostatin on tumor cell growth was studied in vivo in mice (sarcoma 180 ascites tumor and Lewis lung tumor) and in vitro on nontransformed and polyoma-transformed cell lines. 4 or 20 g/100 g of cyclic somatostatin and 4 g/100 g of linear protamin Zn-bound somatostatin were injected s.c. twice daily in the in vivo study. Cyclic somatostatin (1, 4 or 10 g/ml) was added twice daily to the cell cultures. Somatostatin administration influenced neither the survival of animals nor the growth rate of cultured cell lines. *** DIRECT SUPPORT *** A2025117 00011  相似文献   

7.
Summary Precocene and analogs added to the meal of 4th instar larvae ofRhodnius prolixus were tested as antifeedants. While precocene II had a strong antifeedant effect (ED50=48 g/ml), the other compounds showed no drastic inhibition of feeding (ED50>140 g/ml). ATP, a phagostimulant, did not reverse the antifeedant action of precocene II. The mechanism of feeding inhibition is discussed.Acknowledgments. This research was supported by funds from Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, and National Science Foundation grants PCM-76-09647 and PCM-79-03245.  相似文献   

8.
Summary Giant melanosomes, ellipsoidal (1.5 m×1.3 m) or spherica (1.1 m–1.4 m in diameter) exist in the scrotal skin of the black pelted Long Evans rat. They are longer and wider than normal stage IV melanosomes (0.7 ×0.4 m) found in theses dermal melanocytes.The authors acknowledge with gratitude, the technical assistance of Evelyn Ann Flynn. This work was supported by grant AM 20669-16 from the National Institute of Arthritis, Metabolism, and Digestive Diseases, USPHS.  相似文献   

9.
Summary Uptake ofd-glucose anomers by isolated rat retina was studied. After 3 min incubation at 37°C in the presence of or anomer (750 g/ml), a significantly greater uptake (1.32 mg/g wet tissue) of -anomer was observed compared with that of -d-glucose (1.11 mg/g wet tissue). This result and other data suggest that the carrier ford-glucose transport in the retina prefers the -anomer stereospecifically.Acknowledgment. The authors are grateful to Mr S. Suzuki for his technical assistance.  相似文献   

10.
ATP-dependent Ca++-Extrusion from human red cells   总被引:1,自引:0,他引:1  
Zusammenfassung In einer Lösung mit 1,39M/ml Ca++ waren rekonstituierte menschliche Erythrozyten im Stande, ihren ursprünglichen Ca-Gehalt von 2,39M/ml Zellen in 60 min bei 37 °C auf 0,46M/ml Zellen zu senken, sofern sie Mg-ATPat enthielten. Dieser aktive Transport war durch g-Strophanthin nicht hemmbar, konnte aber mit 5 · 10–4 M Salyrgan unterdrückt werden.  相似文献   

11.
Summary Intraperitoneal injection of zinc raised levels of a hepatic metallothionein-like species. Assuming that this species was metallothionein (MT) then levels were raised from approximately 20 g/g to 300 g/g in 7 days, and levels thereafter remained high for the next 4 weeks. The half-lives of the protein in liver and kidney from starved fish, measured using in vivo incorporation of35S cysteine at 11°C, were approximately 27 days and 32 days respectively. The following agents failed to stimulate synthesis of MT in plaice: stress (due to catching), endotoxin, dexamethasone, cortisol and turpentine.  相似文献   

12.
Summary Culture of L-929 fibroblasts in the presence of phenytoin (2.5–5.0 g/ml) increased DNA synthesis, as indicated by increased [3H]thymidine uptake, while a higher dose (20 g/ml) inhibited DNA synthesis. In like manner, a low dose of phenytoin (5.0 g/ml) was effective in increasing inositol 1,4,5-trisphosphate formation while a higher dose (10 g/ml) tended to inhibit this activity. These data suggest that the formation of inositol phosphate second messengers may play a role in phenytoin-induced fibroblast proliferation and connective tissue growth.  相似文献   

13.
Summary The level of metallothionein-like proteins was determined in different tissues of 6 animal species. The highest concentrations were found in pig and rat tissues. The organs richest in metallothionein-like proteins included: kidneys (101–305 g/g), intestine (127–257 g/g) and liver (54–496 g/g).Studies performed under the Polish-American agreement 05-009-2 with National Institute for Occupational Safety and Health, PHS, USA.  相似文献   

14.
Antidiuretic effects of oxytocin in the Brattleboro rat   总被引:1,自引:0,他引:1  
Summary The antidiuretic activity of oxytocin (OT) was measured in Brattleboro rats with congenital diabetes insipidus. A dose dependent antidiuretic response was found in animals receiving chronic infusions of 0.1 g/h, 1.0 g/h, and 5 g/h of OT. OT infused at the rate of 5 g/h over a 7-day period completely reversed the symptoms of diabetes insipidus. The results support the concept that OT serves as a weak agonist of vasopressin at the level of the kidney and at pharmacological levels exhibits antidiuretic activity.  相似文献   

15.
Phytoalexins, defensive compounds produced by plants against microbial infections, were purified fromSophora exigua (Leguminosae) and their growth inhibitory effects on oral cariogenic bacteria were determined in vitro. Among three isolated compounds, 5,7,2,4-tetrahydroxy-8-lavandulylflavanone completely inhibited the growth of oral bacteria including primary cariogenic mutans streptococci, other oral streptococci, actinomycetes, and lactobacilli, at concentrations of 1.56 to 6.25 g/ml.  相似文献   

16.
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   

17.
Using bioassay guided isolation, three novel 12 carbon polyoxygenated fatty acids and a novel abietane diterpene have been isolated from the the chloroform extract of aerial parts ofAeollanthus buchnerianus (Lamiaceae). Rigorous spectroscopic methods were used for compound identification. (Z,Z)-8-acetoxy-5-hydroxydodeca-2,6-dienoic acid and (Z,Z)-5,8-dihydroxydodeca-2,6-dienoic acid inhibited the spore germination ofCladosporium cucumerinum (both with Minimum Inhibitory Dose (MID) values of 1 g) andAspergillus niger (MID 5 and 25 g respectively). Further, they also reduced the hyphal growth ofPythium ultimum. (Z)-5-hydroxy-6,7,8-triacetoxydodeca-2-dienoic acid exhibited short term inhibition of the growth ofCladosporium cucumerinum. The novel abietane diterpenoid, (rel)-14-acetoxyabiet-7-en-18-oic acid inhibited the growth of the gram positive bacteriaBacillus subtilis, staphylococcus aureus andStreptomyces scabies (MIC values 80, 20 and 20 g ml–1 respectively).  相似文献   

18.
Summary A strain ofClaviceps purpurea, labelled 231 F.I., produced in submerged culture 1200 /ml of a mixture of peptidic alkaloids composed for 30% by -ergokryptine. Cultural media, conditions of culture and development features of a typic fermentation are reported.  相似文献   

19.
Conclusion Geminus account of lunar motion in chapter 18 of hisIntroductio astronomiae is, in our view, an important contribution to Greco-Latin astronomy because, in attempting to reconstruct arithmetically (the parameters of) the Moon's motion in longitude, he undermines the task astronomers had hitherto set for themselves. This undermining of a commonly acknowledged view of the purpose of astronomy is articulated in a whole new set of questions concerning the nature and place of both observation and mathematical reasoning in the science of the heavens. Yet, one must not overlook the fact thatGeminus reconstruction also indicates resources for addressing these questions. Of these resources, the most powerful proved to be the idea that irregular motion could be quantified as a systematic departure from a mean motion, and the idea that observational data could be organized and structured by means of genetic arithmetical reconstructions.But, since we limit our attention to extant treatises and decline to speculate about works or parts of works that have not survived, we must say that it would takePtolemy to discern the new direction for astronomy thatGeminus opened up and to pursue it. In part, this involved straightening out the conflated conception of mean motion in chapter 18 — the qua arithmetic mean daily displacement can only be anapparent lunar motion in longitude and not one the Moonreally makes, but the same need not be true of the qua periodic mean daily displacement — and determining its proper relation to real and apparent planetary motion. Indeed,Ptolemy's genius lay, we think, in seeing that even though, in assimilating Babylonian astronomy, earlier and contemporary Greco-Latin writers betrayed a confused, inconsistent, and unsophisticated grasp of the proper role of arithmetic, geometry, and observation in astronomical argument [seeBowen 1994], the solution lay in a mathematical reconstruction of the observed celestial motions, in which mean motion played an essential role.  相似文献   

20.
Summary Triweekly i.m. injections of clomiphene citrate (group 1, 25 g/0.5 ml and group II, 50 g/1.0 ml) were administered for a period of 3 months during the preparatory period to female fresh water teleosts exhibiting ovarian recrudescence, while a control group received 0.5 ml of physiological saline throughout the period of experimentation i.e., from February through April. 50 g clomiphene citrate treatment brought about a steady increase in ovarian size, and oocytes began to enlarge and mature and finally ovulation took place in April. This is 4 months ahead of their normal occurrence.The authors wish to express their gratitude to Richardson Merrel Co. for supplying the sample of clomiphene citrate, and Dr K.N. Udupa, Institute of Medical Sciences, Banaras Hindu University, Varanasi for facilities.  相似文献   

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