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71.
Halipegus dubius Klein, 1905 is redescribed and illustrated from a Brazilian frog Leptodactylus ocellatus. The type-material of Halipegus genarchella (Travassos, Artigas & Pereira, 1928) and Halipegus parva (Travassos, Artigas & Pereira, 1928) are redescribed with original figures. New synonyms are proposed: Halipegus salmini Yamaguti, 1958 is considered a synonym of H. genarchella, H. tropicus (Manter, 1936) sensu Kloss (1966) of H. parva and Genarchella lenti Fábio, 1984 of H. overstreeti (Brooks, Mayes & Thorson, 1979) n. comb. 相似文献
72.
Mary K. Vaughan Damon C. Herbert George M. Vaughan Frank J. Weaker Anna I. Esquifino Russel J. Reiter 《Chronobiology international》1988,5(2):107-114
In young adult male rats bearing a donor anterior pituitary gland grafted for 3 weeks under a kidney capsule, serum prolactin (PRL) concentrations were elevated and exhibited a rhythm with the highest values in the light phase. Serum PRL in control animals did not exhibit a significant rhythm. Eutopic pituitary PRL content, manifesting a biphasic (12-hr) rhythm with crests during the day and night in controls, exhibited a similar pattern in grafted rats though an overall reduction in pituitary PRL content was seen in the grafted animals. Neither the normal biphasic serum testosterone rhythm nor the normal 24-hr rhythm (nocturnal surge) of pineal N-acetyltransferase activity and melatonin content were altered in the hyperprolactinemic rats. Serum thyroxine (T4) and triiodothyronine (T3) and their free indices (FT4 I, FT3 I) and serum thyrotropin (TSH) were highest during the day in controls and grafted rats and a 12-hr rhythmic component was detected in data for these variables. In the grafted animals, the 12-hr component was reflected in an additional peak at night detectable by testing of means. The overall serum T4 FT4 I, and TSH levels were lower in grafted rats though overall T3 and FT3I levels did not differ between grafted and controls. T3 uptake (T3 U) values were similar between controls and grafted rats, in both cases exhibiting a fall during the night. Changes in serum thyronines could not be explained by changes in serum binding as assessed by the T3U3 and thus may represent changes in thyroidal secretion of T4. The rhythm in serum PRL of grafted rats suggests the presence of rhythmic circulating factor(s) capable of influencing ectopic lactotrophs. The reduced eutopic pituitary PRL content suggests a role for PRL in influencing eutopic lactotrophs in the pituitary-grafted hyperprolactinemic male rat model. Though circulating testosterone and pineal melatonin synthesis were not altered in this model, thyroid function appeared to be so. 相似文献
73.
Anna Maria Greco Pasquale Gambardella Raffaella Sticchi Diego D'aponte Pietro De Franciscis 《Chronobiology international》1988,5(3):217-225
Circadian rhythms of serotonin (5HT), its precursors tryptophan (TP) and 5-hydroxy-tryptophan (5HTP) and its acid catabolite 5-hydroxy-indoleacetic acid (5HIAA), were determined in the hypothalamus of control rats and rats which had been treated continuously with subcutaneous imipramine (10 mg/kg/day) for 2 weeks.
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
74.
Anna Krahulcová 《Folia Geobotanica》1988,23(4):375-381
Chromosome numbers of the following nine taxa of the Czechoslovak flora are given:Atriplex rosea L.,Cardamine resedifolia L.,Groenlandia densa (L.)Fourr.,Isoëtes lacustris L.,Lysimachia nemorum L.,Parnassia palustris L.,Phelipanche caesia (Rchb.) Soják,Rumex patientia L. subsp.patientia andSymphytum officinale L. s. str. A new chromosome number of 2n=80 is reported forRumex patientia L. subsp.patientia. Chromosome numbers of another five taxa are first reported from Czechoslovakia. Each of the ascertained chromosome counts is discussed with respect to hitherto known reports. 相似文献
75.
V G Savchenko V G Isaev E M Abakumov N D Khoroshko A G Turkina A N Sokolov M M Viadro S M Navashin 《Antibiotiki i khimioterapii͡a》1992,37(7):47-49
The clinical efficacy of aclarubicin, an anthracycline antibiotic, was studied in 48 patients with leukemia. The antibiotic was used in the following combinations with cytarabine: "7 + 7", "5 + 5" and "7 & 3". A complete remission was stated in 14 (42.4 per cent) out of 33 patients with acute nonlymphoid leukemia, 6 (43 per cent) out of the 14 patients having relapses. The combined therapy was effective in 4 out of 5 pre-resistant patients. The "7 + 3" scheme was the most beneficial. The most common adverse reactions were nausea and vomiting. 相似文献
76.
Giampaolo Manao Luigia Pazzagli Paolo Cirri Anna Caselli Guido Camici Gianni Cappugi Ahmad Saeed Giampietro Ramponi 《Journal of Protein Chemistry》1992,11(3):333-345
Two lowM
r phosphotyrosine protein phosphatases have been isolated from rat liver. The enzymes were previously known as lowM
r acid phosphatases, but several recent studies have demonstrated that this family of enzymes possesses specific phosphotyrosine protein phosphatase activity. We determined the complete amino acid sequences of the two isoenzymes and named them AcP1 and AcP2. Both consist of 157 amino acid residues, are acetylated at the NH2-terminus, and have His as the COOH-terminus. The molecular weights calculated from the sequences are 18,062 for AcP1 and 17,848 for AcP2. They are homologous except in the 40–73 zone, where about 50% of residues are different. This fact suggests that the two isoenzymes are produced by an alternative splicing mechanism. There is no homology between these two isoenzymes and the receptor-like phosphotyrosine protein phosphatases LAR, CD45, human placenta PTPase 1B, and rat brain PTPase-1. AcP1 and AcP2 are also distinct from rat liver PTPase-1 and PTPase-2, since these last enzymes have higher molecular weights. AcP1 differs from AcP2 with respect to (1) substrate affinity and (2) its sensitivity to activators and inhibitors, thus suggesting a their different physiological function. 相似文献
77.
Stefano M. Candura Anna F. Castoldi Luigi Manzo Lucio G. Costa 《Neurochemical research》1992,17(11):1133-1141
Guanine nucleotide-, neurotransmitter-, and fluoride-stimulated accumulation of [3H]inositol phosphates ([3H]InsPs) was measured in [3H]inositol-labeled synaptoneurosomes from cerebral cortex of immature (7-day-old) and adult rats, in order to clarify the role of GTP-binding proteins (G-proteins) in modulating phosphoinositide (PtdIns) metabolism during brain development. GTP(S) [Guanosine 5-O-(3-thio)triphosphate] time- and concentration-dependently stimulated PtdIns hydrolysis. Its effect was potentiated by full (carbachol, metacholine) and partial (oxotremorine) cholinergic agonists through activation of muscarinic receptors. The presence of deoxycholate was required to demonstrate agonist protentiation of the guanine nucleotide effect. The response to GTP(S) was higher in adult than in immature rats, while the effect of cholinergic agonists was similar at the two ages examined. At both ages, histamine potentiated the effect of GTP(S), while norepinephrine was ineffective. At both ages, guanosine 5-O-(2-thio)diphosphate [GDP(S)] and pertussis toxin significantly decreased GTP(S)-induced [3H]InsPs formation. The phorbol ester phorbol 12-myristate 13-acetate (PMA), on the other hand, did not inhibit the guanine nucleotide response in synaptoneurosomes from immature rats. NaF mimicked the action of GTP(S) in stimulating PtdIns hydrolysis. Its effect was not affected by carbachol and was highly synergistic with that of AlCl3, according to the concept that fluoroaluminate (AlF4
–) is the active stimulatory species. No quantitative differences were found in the response to these salts between immature and adult animals. These results provide evidence that, in both the immature and adult rat brain, neuroreceptor activation is coupled to PtdIns hydrolysis through modulatory G-proteins. 相似文献
78.
Isolated protoplasts from C. officinalis leaves were supplied with [3-3H]oleanolic acid, its 3-O-monoglucoside and 3-O-monoglucuronide. Transformations of these compounds into two series of oleanolic acid glycosides, i.e. glucosides (derivatives of 3-O-monoglucoside) and glucuronides (derivatives of 3-O-monoglucuronide) in the extravacuolar space and the vacuole were investigated. In the cytoplasm free oleanolic acid is glycosylated to both monoglycosides and to higher glycosides. Monoglycosides are partly hydrolysed to free oleanolic acid and partly glycosylated to higher derivatives. The vacuole contains the same radioactive compounds as the extravacuolar space. However, it seems most likely that these compounds are transported there from the sites of their synthesis in the cytoplasm. 相似文献
79.
Murielle Reboul Bernard Frangoulis Anna Rocca Laurent Degos Marika Pla 《Immunogenetics》1991,34(3):196-200
As a basis for the characterization of mouse T cells involved in the recognition of xenogeneic HLA molecules, a panel of HLA-B27-reactive cytotoxic T-cell clones was generated upon stimulation by cells from HLA-B27-transgenic mice. The HLA-B27-induced T-cell response was found to comprise two categories of clones: some recognizing HLA-B27 independent of H-2 molecules expressed by the target cells (unrestricted clones), others recognizing HLA-B27 in an H-2 restricted manner. The unrestricted clones exhibited diverse specificities, as judged from their various cross-reactivities with other xenogeneic (HLA) or allogeneic (H-2) molecules. In addition, although most of the unrestricted clones were able to react with both mouse and human HLA-B27-transgenic mice. The HLA-B27 induced T-cell which reacted only with HLA-B27-positive mouse, and not human cells. These findings illustrate that both H-2-restricted and unrestricted T cells with diverse species contribute to HLA-B27-xenorecognition. 相似文献
80.
N N Sokolov M A El'darov N V Anike?cheva I V Karpychev O T Samko A B Fitsner A A Kalugin E B Khoroshutina K G Skriabin 《Bioorganicheskaia khimiia》1991,17(9):1188-1192
A new site-specific endonuclease was detected in toluene lysates of Bacillus coagulans AUCM B-732 and designated as BcoAI. The enzyme was purified by fractionation of the cell-free extract in the two-phase PEG/dextran system followed by chromatography on DEAE-sepharose and phosphocellulose and shown to be free of nonspecific nucleases and phosphatases. BcoAI has three cleavage sites on lambda DNA, but does not cleave SV40, pBR322 and pUC19 DNA. BcoAI recognizes the sequence 5' CAC decreases GTG 3' on double-stranded DNA and cleaves it as indicated by the arrow to yield blunt-ended DNA fragments. Thus, BcoAI is a true isoschizomer of PmaCI from Pseudomonas maltophila C. 相似文献