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1.
The potency of estrone, estradiol, estriol, and equilenin, administered to mice subcutaneously or intravaginally, was quantitated by vaginal mitotic index and by epithelial thickness; results were compared with those previously obtained in the classical tests of rat vaginal cornification and uterotrophic activity in mice. Ovariectomized mice received .002-.7 mcg estrogens in oil sc, or .16-6250 pg in alcohol solution intravaginally. 19 hours later .1 mg colchicine was given to arrest cells in metaphase. 24 hours after estrogen treatment, vaginas were a positive log-dose response in both tests and by both routes. Estradiol by both routes increased vaginal thickness but without linear dose-response, increased vaginal mitosis with a less definite dose response, but generated a negative dose response in mitotic index. Equilenin had a positive but nonlinear effect by both routes in both tests. Comparing the activities of these estrogens by routes, estradiol was more active by subcutaneous than by intravaginal routes; estriol and equilenin were more active vaginally than subcutaneously. Estradiol was 3-7 times more active than estrone intravaginally and 25-45 times more active subcutaneously. Estriol was less active than estrone; equilenin was as active as estrone intravaginally, but less active subcutaneously. In comparison with the rat vaginal cornification or mouse uterotrophy tests, estradiol sc, estriol and equilenin sc and especially vaginally, are much more active.  相似文献   

2.
目的了解临床使用消毒饮用水稀释益生菌产品,对益生菌活菌数的影响。方法配制不同有效氯水溶液,测定不同放置时间四个菌种活菌数变化情况。结果微囊包被屎肠球菌、蜡样芽胞杆菌在有效氯5 ppm和10ppm中使用有效活菌数不受任何影响;微囊包被粪肠球在有效氯5 ppm中浸泡2 h内使用,不影响其有效活菌;而在10ppm中1 h之内使用有效活菌数不受影响;微囊包被枯草芽胞杆菌在有效氯5 ppm中1 h之内活菌数不受影响,而增加浸泡时间及有效氯浓度都会影响其有效活菌数。结论在临床使用微生态产品可以使用含氯消毒饮用水稀释但是需尽快用完不要超过否则影响部分菌株的使用效果。  相似文献   

3.
The stilbenoids E-resveratrol (E-3,5,4'-trihydroxystilbene, 1), E-3,5,4'-trimethoxystilbene (2), E-3,4,4'-trimethoxystilbene (3) and E-3,4'-dimethoxy-5-hydroxystilbene (4) were converted by photoisomerization to their corresponding Z-isomers 5-8. Compounds 1-8 were subjected to antiproliferative activity bioassays towards a set of four different human cancer cell lines, namely DU-145 (androgen not responsive human prostate tumor), LNCaP (androgen responsive human prostate tumor), M-14 (human melanoma) and KB (human mouth epidermoid carcinoma). The methylated analogues of 1 are more active than the natural lead in the majority of bioassays. The most active compound was Z-3,5,4'-trimethoxystilbene (6), which showed against DU-145 and LNCaP cells GI50 values close to those of the anticancer drug vinorelbine; 6 resulted more active than its E-isomer 2 towards DU-145, LNCaP and especially KB cell lines. A number of methylated Z-isomers displayed a higher activity than their E-isomers, but E-resveratrol (1) was more active than Z-resveratrol (5) towards all the tested cell lines.  相似文献   

4.
5.
Chloroperoxidase from Caldariomyces fumago was crystallized. The crystals were modified with several cross-linkers, but only glurataldehyde was able to produce catalytically active and insoluble crystals. Unlike other immobilized chloroperoxidase preparations, these catalytic crystals are more thermostable than the unmodified soluble enzyme. The enhanced stability is probably due to the structure conservation in the crystalline matrix. In addition, non-cross-linked chloroperoxidase crystals retained more activity than the soluble enzyme after incubation in an organic solvent with low water content. Although the cross-linked crystals were catalytically active, they showed lower specific activity than the soluble enzyme. This low activity may be due to non-specific reactions between the cross-linker and essential residues for catalysis. Alternative cross-linking strategies are discussed.  相似文献   

6.
Marwah P  Marwah A  Kneer N  Lardy H 《Steroids》2001,66(7):581-595
The 7-oxo derivative of dehydroepiandrosterone is more active than the parent steroid and is devoid of adverse side effects in rats, monkeys and humans. In anticipation of possible therapeutic use we have sought more active, longer lasting forms of 7-oxo- and 7beta-hydroxydehydroepiandrosterones. The 7-oxo- and 7-hydroxy steroids have been converted to glucuronides, ethers and carbonate esters. The syntheses of these compounds are described and their ability to induce the formation of liver thermogenic enzymes when fed to rats is reported. Some of the new derivatives were found to be somewhat more effective than the equimolar amounts of 7-oxo-DHEA with which they were compared in each experiment.  相似文献   

7.
Procedures are described for preparing monomeric selectively S-carboxamido-methylated and S-aminoethylated derivatives of seminal ribonuclease. The main properties of the derivatives, including their extinction coefficients, have been determined. Their catalytic activities and that of the S-carboxymethyl derivative have been tested. On double-stranded RNA as a substrate the monomeric derivatives are less active than the native dimeric enzyme, but much more active than pancreatic ribonuclease. On yeast RNA as a substrate the amino-ethyl derivative is found to be less active (80%) than the native enzyme, while the other two are over 30 percent more active. The monomers are stable in solution and when lyophilized from acetic acid solution do not associate to the same extent as pancreatic or native seminal ribonucleases.  相似文献   

8.
Spiro[aziridine-2,2'-adamantanes] 1 and 2, spiro[azetidine-2,2'-adamantanes] 3 and 5, spiro[azetidine-3,2'-adamantane] 13, spiro[piperidine-4,2'-adamantanes] 25 and 27, and spiro barbituric analog 18 were synthesized and tested for their anti-influenza A virus properties and for trypanocidal activity. The effect of ring size on potency was investigated. Piperidine 25 showed significant anti-influenza A virus activity, being 12-fold more active than amantadine, about 2-fold more active than rimantadine, and 54-fold more potent than ribavirin. It also proved to be the most active of the compounds tested against bloodstream forms of the African trypanosome, Trypanosoma brucei, being 1.5 times more potent than rimantadine and at least 25 times more active than amantadine.  相似文献   

9.
Spiromorpholinone derivatives were synthesized from androsterone or cyclohexanone in 6 or 3 steps, respectively, and these scaffolds were used for the introduction of a hydrophobic group via a nucleophilic substitution. Non-steroidal spiromorpholinones are not active as inhibitors of 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3), but steroidal morpholinones are very potent inhibitors. In fact, those with (S) stereochemistry are more active than their (R) homologues, whereas N-benzylated compounds are more active than their non substituted precursors. The target compounds exhibited strong inhibition of 17β-HSD3 in rat testis homogenate (87–92% inhibition at 1 μM).  相似文献   

10.
PAN and leukocytolysis were measured in dog blood placed in hypo- and hypertonic solutions of glycerin and glucose (1:10). It was found that leukocytolytic activity of the substances depends on equimolar concentrations of nonelectrolytes. It is more pronounced in hypo- than in hypertonic conditions. Glycerin is 3-5-times more active than glucose. In concentrations 2.0 M for glycerin and 0.5 M for glucose leukocytolysis is less active. Mononuclears are more resistant than neutrophils in strong solutions. PAN increased by 11-16% in hypotonic solutions. Strong glycerin solutions reduce PAN less than glucose which stimulates the digestive activity. The results can be of use in specific leukolysis tests to diagnose drug allergy.  相似文献   

11.
Pharmacological receptors for substance P and neurokinins   总被引:31,自引:0,他引:31  
The three neurokinins identified in mammals, substance P, neurokinin A and neurokinin B, as well as their C-terminal biologically active fragments, have been used to characterize the responses of a variety of isolated organs. Three preparations selective either for substance P (the dog carotid artery), or for neurokinin A (the rabbit pulmonary artery) or for neurokinin B (the rat portal vein) are described. A neurokinin receptor classification is attempted using the neurokinins and their fragments to determine the order of potency of agonists. Three receptor subtypes have been identified: the NK-P, on which substance P (SP) is more active than neurokinin A (NKA) and neurokinin B (NKB), and the neurokinins are more active than their respective fragments; the NK-A on which NKA greater than NKB greater than SP, and some NKA fragments are more discriminative than their precursor; the NK-B on which NKB greater than NKA greater than SP, and fragments of NKB are less active than their precursor. Among the peptides studied, some potent compounds have been identified that could provide selective receptor ligands.  相似文献   

12.
13.
The plant growth-regulating activities of all the mono- and di-chloro-substituted α-hydroxy-phenylacetic (mandelic) acids and their methoxy derivatives have been determined in the wheat coleoptile cylinder, pea segment and pea curvature tests. In general, chloro-substituted α-hydroxy acids were less active in all three tests than the corresponding α-methoxy acids. The α-methoxy compounds and the dichloromandelic acids were more active in pea than in wheat tissues. These results are discussed in relation to the plant growth-regulating activities of the corresponding phenylacetic and phenoxyacetic acids.  相似文献   

14.
Novel N,O-acyl chitosan (NOAC) derivatives were synthesized to examine their fungicidal activity against the gray mould fungus Botrytis cinerea (Leotiales: Sclerotiniaceae) and the rice leaf blast fungus Pyricularia oryzae (Teleomorph: Magnaporth grisea). The fungicidal activity was evaluated by the radial growth bioassay. NOAC derivatives were more active against the two plant pathogens than chitosan itself, and the effect was concentration dependent. Against B. cinerea, 4-chlorobutyryl chitosan (EC50=0.043%), decanoyl chitosan (EC50=0.044%), cinnamoyl chitosan (EC50=0.045%), and p-methoxybenzoyl chitosan (EC50=0.050%) were the most active (12-13-fold more active than chitosan). (Un)-substituted benzoyl chitosan derivatives were more active against B. cinerea than most of these with N,O-alkyl derivatives. Against P. oryzae chitosan derivatives with lauroyl, methoxy acetyl, methacryloyl and decanoyl were the most active.  相似文献   

15.
Previous work suggested differences in allozyme frequencies between samples of monarch butterflies collected at different times of the day. This study examines the prediction that some individuals are active consistently earlier in the day than others. Four specific hypotheses were tested: (1) Individuals caught early on one day were more likely than those caught late to be caught early on subsequent days. This was true in some experiments. (2) Individuals caught early in the field were more likely than those caught late to fly early in outdoor flight cages. This was true when outdoor temperatures were low (between 10 and 20oC) but not when they were above 20oC. (3) Individuals caught early in the field were more likely to be able to fly at low body temperatures than those caught late. This was not true. (4) Individuals that flew early in outdoor flight cages were more likely to be able to fly at low body temperatures. This was not true. Overall we conclude, on the basis of field and flight cage experiments, that some individuals are active consistently earlier in the day than others. The lack of a relationship between field and temperature cabinet results indicates that this is not purely a result of differences in ability to fly at low body temperatures. The implications of these results are discussed.  相似文献   

16.
The Cu,Zn superoxide dismutases from bovine liver, yeast, Caulobacter crescentus, and Photobacter leiognathi were compared for their susceptibilities to inhibition by cyanide and to inactivation by hydrogen peroxide and phenylglyoxal. All of these enzymes were affected by these reagents, albeit with some differences in sensitivity. The yeast and the bacterial enzymes were thus more sensitive to cyanide than was the bovine enzyme, while the bovine and the yeast enzymes were inactivated more rapidly by hydrogen peroxide and less rapidly by phenylglyoxal than were their bacterial counterparts. The qualitative similarities in the behavior of all of these enzymes suggest overriding similarities in their active site regions. However, a quantitative comparison of the data suggests that the bacterial enzymes are more like each other than they are like the eucaryotic enzymes, and furthermore, are more like the yeast enzyme than the bovine enzyme.  相似文献   

17.
The in-vitro antibacterial activities of erythromycin, lincomycin, and clindamycin, a new derivative of lincomycin, were compared. Clindamycin was always more active than lincomycin, and was either as active as erythromycin or more so against betahaemolytic streptococci, Streptococcus viridans, Str. pneumoniae, and erythromycin-sensitive Staphylococcus aureus. It was also fully active against most erythromycin-resistant strains of Staph. aureus. On the other hand, it was somewhat less active than erythromycin against Haemophilus influenzae and considerably less active than erythromycin against Str. faecalis and Neisseria gonorrhoeae.Clinical trials seem to be justified in infections with sensitive organisms for which erythromycin might have been indicated.  相似文献   

18.
The study of 8 C. diphtheriae strains of different origin revealed that these strains were capable of inducing the agglutination of trypsinized sheep red blood cells (SRBC). Toxigenic strains gravis isolated from diphtheria patients were more active in their adhesion to SRBC than toxigenic strains gravis isolated from carriers. The latter were, in their turn, more active than nontoxigenic strains mitis. No fimbriae were detected on the cell surface by electron microscopy.  相似文献   

19.
The state of adenylate system and intensity of oxidative phosphorylation in liver mitochondria of active and hibernating ground squirrels were studied depending on the concentration of extramitochondrial Ca2+ ([Ca2+]ex). It was shown that at [Ca2+]ex.10(-7) M, the content of ATP as well as ATP/ADP ratio are slightly lower in the mitochondria of hibernating ground squirrels than in the mitochondria of active animals. The other parameters of the adenylate system under the same conditions differ insignificantly. [Ca2+]ex increase to 10(-6) M has little effect on the parameters of the adenylate system of active animals. On the contrary, the mitochondria of hibernating ground squirrels are strongly affected: the level of ATP is 1.5-fold and the ratio of ATP/ADP is almost 2-fold decreased. At both [Ca2+]ex the intensity of oxidative phosphorylation is essentially higher in the mitochondria of active ground squirrels. With increasing [Ca2+]ex the rate of ATP synthesis decreases, and in the mitochondria of hibernating animals the decrease is more pronounced than in the mitochondria of active animals. Thus, oxidative phosphorylation and adenylate system of mitochondria from hibernating ground squirrels are more sensitive to [Ca2+]ex increase than those of the mitochondria of active animals.  相似文献   

20.
An Insect Activity Monitor was created to measure the behavioural responses of fleas (Siphonaptera). The apparatus allows for a range of visual, chemo- and mechanoreceptor cues to be presented. The jumping response is detected by counting amplified pulses produced as the fleas land on a stretched membrane held over a microphone. Horizontal movements are detected using a system of infra-red beams and phototransistors which, when broken, are counted as a measure of activity. The apparatus was tested using Ceratophyllus hirundinis (Curtis), Ceratophyllus farreni (Rothschild) and Ceratophyllus rusticus (Wagner), co-inhabiting species from the nests of the house martin (Delichon u.urbica L.). No unaided emigration or immigration has been demonstrated in these species (Clark, 1988) and much of their time is spent confined to the darkness of the nest. In addition to species contrasts, females were more active than males and fleas were more active at 25 degrees C than at 18 degrees C. The more active bird flea Ceratophyllus garei (Rothschild) from the nest of pheasant (Phasianus colchicus L), was tested for responses to light of varying intensity. Activity was stimulated by white light, but not proportional to light intensity.  相似文献   

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