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31.
Cardiovascular and pulmonary effects of a new sedative/analgesic (medetomidine) as a preanaesthetic drug in the dog. A study was carried out to investigate the possible usefulness of medetomidine (Farmos Group, Turku, Finland) for premedication prior to general anaesthesia with thiopental sodium and halothane. The main emphasis was laid on the circulatory and respiratory effects of medetomidine. Dogs treated with xylazine (2 mg/kg) or placebo (physiological saline solution) served as controls. Medetomidine caused a decrease in blood pressure, heart rate and respiratory rate at all dose levels tested. These decreases were essentially dose -dependent, but there were great individual variations. It is concluded that the drug can be useful for premedication at the lowest dose level tested (10 μ/kg). The sedative effect, however, is so strong that an even lower dose might be sufficient for the present purpose. 相似文献
32.
Karin Lindström Albert E. G. Kr. Von Dem Borne Michael E. Breimer Bertil Cedergren Yasuto Okubo Lennart Rydberg Susann Teneberg Bo E. Samuelsson 《Glycoconjugate journal》1992,9(6):325-329
A 12-week-old fetus and one 17-week-old fetus + placenta were obtained after spontaneous abortions from two women of blood group p. The 17-week-old fetus was dissected into intestine, liver, brain and residual tissue. Nonacid glycosphingolipid fractions were prepared from the tissues. Glycolipid characterization was carried out using thin layer chromatography immunostained with monoclonal antibodies and bacteria and by1H NMR spectroscopy and mass spectrometry. In the placental fraction substantial amounts of globotetraosylceramide (P-antigen) and globotriaosylceramide (Pk-antigen) were identified. In contrast, the fetuses contained only trace amounts of these structures, as revealed by immunostaining. These results indicate that the primary target for the antibodies of the anti-Tja serum is the placenta tissue, resulting in termination of the pregnancy. 相似文献
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34.
In a previous work (Kömen et al. 1991) it has been concluded that membrane fragments isolated from autotrophically grown Alcaligenes eutrophus H16 contain several iron-sulphur centres along with haems of a-, b-, c-, and d-type. These redox components have been proposed to be part of a branched respiratory chain leading to multiple membrane bound oxidases. Here, some of the respiratory activities catalyzed by membrane fragments from wild type cells of A. eutrophus (H16) and, for comparison, Paracoccus denitrificans, have been investigated through the use of electron transport inhibitors. Cyanide (CN-) titration curves indicated that in A. eutrophus H16 oxidation of succinate and H2 preferentially proceeds via the cytochrome c oxidase(s) branch (I 50=2 · 10-5 M) whereas the NADH dependent respiration started being inhibited at higher CN- concentrations (I 50=5 · 10-4 M). In membranes isolated from both, cells harvested at late growth-phase (OD 12) and from a mutant deficient in cytochrome c oxidase activity (A. eutrophus RK1), respiration was insensitive to low CN- concentrations (< 10-4 M), and it was sustained by the high catalytic activities of two quinol oxidases. These alternative oxidases of b- (formally o-) and d-type showed different sensitivities to KCN (I 50=10-3 M and 10-2 M, respectively). Interestingly, the cytochrome c oxidase(s) dependent respiration of H16 membranes was insensitive to antimycin A but largely inhibited by myxothiazol (10-6 M). This, and previous work (Kömen et al. 1991), suggest that although the respiratory chain of A. eutrophus is endowed with a putative bc 1 complex, its biochemical nature and role in respiration of this organism are apparently different from those of P. denitrificans. The peculiarity of the respiratory chain of A. eutrophus is confirmed by the rotenone insensitivity of the NADH oxidation in both protoplasts and membrane fragments from wild type and soluble hydrogenase deficient cells (HF14 and HF160). A tentative model of the respiratory chain of autotrophically grown A. eutrophus is presented. 相似文献
35.
Cytogenetic and molecular characterization of a newly established neuroblastoma cell line LS 总被引:2,自引:0,他引:2
Günter Rudolph Karin Schilbach-Stückle Rupert Handgretinger Peter Kaiser Horst Hameister 《Human genetics》1991,86(6):562-566
Summary A new human neuroblastoma cell line (LS) that originated from an abdominal tumor of a 16-month-old girl is presented; it was classified, according to Evans, as being stage III. Morphological (dense-core particles) and biochemical characteristics (dopamine--hydroxylase, acetylcholinesterase, neuron-specific-enolase) confirmed the diagnosis. In addition to a slightly variable modal chromosome number of 48 or 49 (because of marker-chromosomes and autosomal trisomies), cytogenetic analysis revealed two constantly appearing chromosomes with homogeneously stained regions (HSR's). The karyo-type remained constant over 50 passages in vitro [49,XX, –12,+der5, + 17,+mar1,+mar2]. Double minutes were a rare phenomenon and appeared only in a few metaphases. In situ hybridization showed that some of the HSR's consisted of amplified N-myc copies. The distribution of the N-myc copies according to in situ hybridization signals along the HSR's was compared with the data of Southern and Northern blotting analyses. 相似文献
36.
Regulation of collagen synthesis in fibroblasts within a three-dimensional collagen gel 总被引:7,自引:0,他引:7
Cornelia Mauch Atsushi Hatamochi Karin Scharffetter Thomas Krieg 《Experimental cell research》1988,178(2):493-503
Fibroblasts cultivated within a three-dimensional collagen gel display an elongated, spindle-like morphology, reduce their proliferation rate, contact the gel to a very dense tissue, and modify their metabolic activity as compared to monolayer cultures. Collagen synthesis measured as protein-bound hydroxyproline is reduced to 5% of the values found in monolayer culture. The reduction involving type I and type III collagen is due to decreased de novo synthesis and not to enhanced degradation. Dot blot hybridization, Northern blot analysis, and in situ hybridization using collagen I- and III-specific cDNA probes demonstrate that reduced biosynthesis rates are reflected by a marked reduction of pro alpha 1 (I), pro alpha 2 (I), and pro alpha 1 (III) collagen mRNA indicating pretranslational regulation. A similar reduction was observed for actin mRNA whereas levels of tubulin mRNA were similar for fibroblasts in monolayer culture or cultivated within the three-dimensional collagen gels. The data suggest a specific reprogramming of various cellular activities in response to contact with the reconstituted extracellular matrix. 相似文献
37.
Using different independent procedures for assaying soluble auxin-binding in etiolated pea epicotyls, wo could prove the reliability
of the (XH4)2SO4-pelleting assay both for crude cytosols as well as for specific protein fractions obtained after chromatofocusing. Three
distinct genotypes (two parent lines, one tall recombinant) investigated so far exhibit characteristic differences with respect
to soluble auxin-binding kinetics in their cytosols. 相似文献
38.
ESCHERICHIA COLI Rho Factor Is Involved in Lysis of Bacteriophage T4-Infected Cells 总被引:4,自引:0,他引:4
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A Rid (Rho interaction deficient) phenotype of bacteriophage T4 mutants was defined by cold-sensitive restriction (lack of plaque formation) on rho+ hosts carrying additional polar mutations in unrelated genes, coupled to suppression (plaque formation) in otherwise isogenic strains carrying either a polarity-suppressing rho or a multicopy plasmid expressing the rho+ allele. This suggests that the restriction may be due to lower levels of Rho than what is available to T4 in the suppressing strains.--Rid394 X 4 was isolated upon hydroxylamine mutagenesis and mapped in the t gene; other t mutants (and mot, as well as dda dexA double mutants) also showed a Rid phenotype. In liquid culture in strains that restricted plaque formation Rid394 X 4 showed strong lysis inhibition (a known t- phenotype) but no prolonged phage production (another well-known t- phenotype). This implies that when Rho is limiting the t mutant shuts off phage production at the normal time. Lysis inhibition was partially relieved, and phage production prolonged to varying extents depending on growth conditions in strains that allowed plaque formation. No significant effect on early gene expression were found. Apparently, both mutant (polarity-suppressing) and wild-type Rho can function in prolonging phage production and partially relieving lysis inhibition of Rid394 X 4 when present at a sufficiently high level, and Rho may play other role(s) in T4 development than in early gene regulation. 相似文献
39.
40.
Organization of the ribosomal ribonucleic acid genes in various wild-type strains and wild-collected strains of Neurospora 总被引:6,自引:0,他引:6
Peter J. Russell Sheryl Wagner Karin D. Rodland Rhonda L. Feinbaum Jennifer P. Russell Marion S. Bret-Harte Stephen J. Free Robert L. Metzenberg 《Molecular & general genetics : MGG》1984,196(2):275-282
Summary The organization of the ribosomal DNA (rDNA) repcat unit in the standard wild-type strain of Neurospora crassa, 74-OR23-1A, and in 30 other wild-type strains and wild-collected strains of N. crassa, N. tetrasperma, N. sitophila, N. intermedia, and N. discreta isolated from nature, was investigated by restriction enzyme digestion of genomic DNA, and probing of the Southern-blotted DNA fragments with specific cloned pieces of the rDNA unit from 74-OR23-1A. The size of the rDNA unit in 74-OR23-1A was shown to be 9.20 kilobase pairs (kb) from blotting data, and the average for all strains was 9.11+0.21 kb; standard error=0.038; coefficient of variation (C.V.)=2.34%. These data indicate that the rDNA repeat unit size has been highly conserved among the Neurospora strains investigated. However, while all strains have a conserved HindIII site near the 5 end of the 25 S rDNA coding sequence, a polymorphism in the number and/or position of HindIII sites in the nontranscribed spacer region was found between strains. The 74-OR23-1A strain has two HindIII sites in the spacer, while others have from 0 to at least 3. This restriction site polymorphism is strain-specific and not species-specific. It was confirmed for some strains by restriction analysis of clones containing most of the rDNA repeat unit. The current restriction map of the 74-OR23-1A rDNA repeat unit is presented. 相似文献