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1.
Cs. Leranth H. Sakamoto N. J. MacLusky M. Shanabrough F. Naftolin 《Histochemistry and cell biology》1985,82(2):165-168
Summary A pre-embedding immunostaining procedure was developed using ferritin and peroxidase to enable simultaneous electron microscopic localization of two antigens in the same tissue section. This method was used to study the anatomic relationship between glutamic acid decarboxylase (GAD) immunoreactive axons and tyrosine hydroxylase (TH) — containing neurons of the rat arcuate nucleus. The findings provide ultrastructural evidence that GAD-immunoreactive terminals establish symmetric (Gray II) synapses on TH-reactive neurons. 相似文献
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3.
Ildikó Vidra Kálmán Simon László Institóris Ingeborg Csöregh Mátyás Czugler 《Carbohydrate research》1982,111(1):41-57
After hydrolysis of 1,6-dibromo-1,6-dideoxygalactitol (1) and 1,2:5,6-dianhydrogalactitol (2), 11 compounds were isolated, three of them as tritylated derivatives. Their structures were established on the basis of chemical evidence and, for four compounds, by X-ray diffraction. The main product of the hydrolysis of 1 was 3,6-anhydro-1-bromo-1-deoxy-dl-galactitol; the end-products of the hydrolysis of 2 were 1,5-anhydro-dl-galactitol, 2,5-anhydro-dl-altritol, and galactitol. 相似文献
4.
Weanling female rats were stressed (by water and food deprivation for two days) and three months later the following indexes were studied: 5-HT and 5-HIAA levels in five brain regions, blood plasma and cerebrospinal fluid (CSF), sexual activity and nocistatin level of the plasma and CSF. The 5-HIAA content of hypothalamus and brainstem was significantly decreased (in the brainstem with one third) and in the striatum significantly increased. Plasma nocistatin level was significantly increased. Meyerson index and lordosis quotient were similar to control, but the estrus frequency almost doubled in the stressed animals. Much more defense reactions were observed in the stressed females during trials of mating. The results demonstrate that, 1) the perinatal period is not only sensitive to the remote-effects of stress but later could also be stress-sensitive critical periods, and 2) the continuously differentiating (e.g. bone marrow) cells are sensitive to late imprinting by stress, as well as to the brain and the sexual system. 相似文献
5.
Incorporation of the carbocyclic analogue of (E)-5-(2-bromovinyl)-2'-deoxyuridine 5'-triphosphate into a synthetic DNA 总被引:1,自引:0,他引:1
J Sági E De Clercq A Szemz? A Csárnyi T Kovács L Otv?s 《Biochemical and biophysical research communications》1987,147(3):1105-1112
The carbocyclic analogue of (E)-5-(2-bromovinyl)-2'-deoxyuridine, C-BVDU, is a very potent and selective anti-herpes-virus compound. In order to synthesize and study the properties of a DNA that contains C-BVDU, the 5'-triphosphate, C-BVDUTP was prepared and evaluated as a potential substrate of the E. coli Klenow DNA polymerase enzyme. Although C-BVDUTP proved to be a very poor substrate also of this enzyme, it could be incorporated up to 3.6% into the synthetic DNA, poly(dA-dT, C-BVDU). This level of substitution decreased significantly the template activity for DNA and RNA polymerases, as compared to that of poly(dA-dT). 相似文献
6.
The habituation of exploration of a goldfish, Carassius auratus, by paradise fish, Macropodus opercularis, was examined. A first encounter of at least 1 min was necessary for habituation to be found in a second encounter 3 h later. When the paradise fish were allowed 5 min to explore the goldfish and the second encounters were staged between 3 h and 3 months later, persistent habituation was found. The relation between memories formed during encounters with other species and modelling of the environment by the paradise fish is discussed. 相似文献
7.
I Gáti M Bergstr?m K Csóka C Muhr J Carlsson 《Prostaglandins, leukotrienes, and essential fatty acids》1990,40(2):117-124
The effects of two specific 5-lipoxygenase inhibitors AA-863 and U-60,257 (piriprost) on the growth of two human glioma cell lines, U-343 MGa and U-251 MG were investigated. Both monolayer cultured cells and spheroids were studied. The results of the monolayer studies showed potent and dose dependent inhibitory effects on the proliferation of glioma cells (IC50/one week treatment/of AA-863: 9.0 microM, IC50 of U-60,257: 40.0 microM). The experiments made on the tumor spheroids suggested an inhibitory effect on proliferation and volume growth already at lower doses (AA-863: 0.4-2.0 microM, U-60,257: 1.0-5.0 microM), a dose range where effects were not found in monolayers. At higher doses (AA-863: 10.0-30.0 microM, U-60,257: 30.0-90.0 microM) the experiments with spheroids failed to demonstrate a further inhibitory effect on spheroid volume, probably attributed to phenomena such as swelling of cells, dissociation of spheroid structure and development of necrosis. The clearly dose dependent inhibitory effect on the proliferation of human glioma cells in monolayer culture and the inhibitory effects on spheroid growth with these specific inhibitors indicate a role for lipoxygenase products in the growth of gliomas. 相似文献
8.
By using a series of aquaria which were more or less separated into two compartments by a "gate" made of plastic or glass strips, we studied how paradise fish changed their patterns of movement relative to the nature of the gates. We found that opaque plastic gates were well recognized by the paradise fish (Macropodus opercularis) even if the strips were very thin, but that they only changed their pattern of movement when the strips exceeded a certain width. Thus, paradise fish appear to be able to distinguish a physical space of the same size as consisting of either one or two compartments, depending on the material (transparency) and width of the dividing strips. 相似文献
9.
Data in the literature suggest that exogenous L-carnitine improves the metabolic function of ischaemic heart cells: it enhances the transport of long-chain fatty acids into the mitochondria, stimulates the slowed beta-oxidation, and moderates the accumulation of amphiphilic acyl esters. A study has therefore been made of the cardiac effects of L-carnitine in dog experiments (n = 8). The left anterior descending coronary artery (LAD) was isolated in anaesthetized, thoracotomized animals in situ. After a control occlusion and equilibration period, the LAD was again ligated at the time of L-carnitine infusion (100 mg/kg iv. during 10 min). The agent diminished the maximal conduction delay and the degree of epicardial ST-segment elevation in the ischaemic myocardial region, and the free fatty acid concentration of the arterial blood, but it did not influence the frequency of ventricular extrasystoles. The anti-ischaemic effect of L-carnitine was manifest only during the infusion, and its discontinuation was immediately followed by an enhanced ST-segment elevation. In the dose applied, the substance did not affect the heart rate, systemic mean arterial pressure, left ventricular end-diastolic pressure (LVEDP), or left ventricular contractility (LV dP/dtmax). In the canine myocardial infarction model employed it was observed that the duration of the anti-ischaemic effect of L-carnitine (100 mg/kg iv.) is very short, and it has no significant antiarrhythmic action. 相似文献
10.
The anaerobic threshold of 37 male and 16 female athletes was studied under laboratory conditions and in the field (4.0 mmol.l-1 lactic acid accumulation was considered as anaerobic threshold). Elite sprinters, middle- and long-distance runners and walkers took part in the study. Sprinters reached the anaerobic threshold first and long-distance runners last, walkers performed it with almost the same speed as sprinters. A two-year follow up of the anaerobic threshold of a female long-distance and a male middle-distance runner was analized for the individual estimation of the physical fitness. 相似文献