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1.
Summary Effects of amygdala stimulation on the discharge activity of antidromically identified supraoptic neurosecretory neurones were studied in male rats anaesthetized with urethane. Stimulation of the medial and the basal amygdala produced excitation or inhibition of discharge activity both in phasically firing (phasic) and in continuously firing (continuous) neurones. More phasic neurones were excited than were inhibited after medial amygdala stimulation. On the other hand, fewer continuous neurones were excited by stimulation of the either amygdala area than were inhibited. This difference of responsiveness between phasic and continuous neurones is statistically significant. Synaptic inputs to supraoptic neurosecretory neurones after amygdala stimulation were also observed in rats with a lesion of the stria terminalis. Supraoptic nucleus stimulation activated antidromically 14 of the 336 amygdala neurones tested. Since phasic neurones have been identified as ADH-secreting neurones, it is concluded that ADH-secreting neurones in the rat supraoptic nucleus receive predominantly excitatory synaptic inputs from the medial amygdala and these amygdalar synaptic inputs are mediated by pathways which are at least in part monosynaptic and are not included in the stria terminalis.Supported by the grants nos. 56440079, 56121007 and 56770057 from the Ministry of Education, Science and Culture, Japan  相似文献   

2.
Summary The mechanism of action of a serum protein isolated from human serum was assessed in several experimental preparations including glycerol-treated muscle fibers, rat heart papillary muscle and isolatedin vitro perfused rat heart. The action of the serum protein was studied also on canine and human heart papillary muscles which were made to respond to electrical stimulation with ultrasonication modified epinephrine. In addition the action of the protein on adenosine 5 triphosphate generated precipitation of purified human actomyosin was investigated.The serum protein enhanced and intensified the generation of ATP induced tension in glycerol-extracted muscle fibers. It intensified the developed tension (DT) and increased the rate of development of tension (dT/dt) without influencing the time peak tension (TPT) of capillary muscles from rat, canine and human hearts in response to electrical stimulation. The serum protein increased the force of contraction of the isolatedin vitro perfused rat heart, and accelerated the adenosine 5 triphosphate generated precipitation of purified human heart actomyosin.  相似文献   

3.
The chemokines interleukin-8 (IL-8) and GRO bind in neutrophils to the interleukin-8 receptor and (IL-8R and ) triggering reorganization of the actin cytoskeleton and activation of phospholipase C (PLC). Reconstitution of chemokine-induced activation of PLC indicated coupling of IL-8R and to pertussis toxin-insensitive or . To identify the signal transduction mechanisms of chemokine-induced actin response, undifferentiated human leukemia cells (HL-60 cells) constitutively expressing , and were chosen for reconstitution studies. Expression of recombinant receptors after transfection of the cells with the cDNA of IL-8R and was confirmed by binding studies with radiolabeled ligands. IL-8R bound IL-8 with high affinity (Kd1 nM) and GRO with low affinity (Kd 1 M), whereas IL-8R bound both IL-8 and GRO with high affinity (Kd1 nM). Flow cytometric actin measurements indicated that high affinity ligand-receptor interactions in both receptor transfectants displayed inducible responses. Pretreatment of transfectants with pertussis toxin caused ADP-ribosylation of G-proteins and blocked chemokine-induced polymerization, indicating involvement of or , but not in this response.accepted by M.J. Parnham  相似文献   

4.
Summary For the budding yeast Saccharomyces cerevisiae the mitotic cell cycle is coordinated with cell mass at the regulatory step start. The threshold amount of cell mass (reflected as a critical size) necessary for start is proportional to nutrient quality. This relationship leads to a transient accumulation of cells at start, termed nutrient modulation, upon enrichment of nutrient conditions. Nutrient enrichment abruptly increases the critical size needed for start, causing the smaller cells, produced in the previous cell cycle, to be delayed at start while growing larger. Here we show that, in S. cerevisiae, a second cell-cycle step, at mitosis, also exhibits nutrient modulation, and is, therefore, another point of cell-cycle regulation. At both mitosis and start, nutrient modulation was found through mutation to be regulated by the activity of the cyclin-related WHI1 (CLN3) gene product.  相似文献   

5.
Summary The influence of transforming growth factor- (TGF-) on hematopoiesis has been evaluated by adding blocking antibodies against TGF- to colony forming assays (CFU-c). When optimum concentrations of recombinant growth factors, granulocyte-macrophage colony stimulating factor (GM-CSF), and interleukin-3 (IL-3) were added to stem cells from the peripheral blood of healthy individuals and certain patients with tumors or HIV infection, the anti-TGF- capable of blocking 5 ng/ml of active TGF- had no significant influence on erythroid or myeloid colony formation. However, in certain immunosuppressed individuals, anti-TGF- resulted in a significant decrease of erythroid colony formation and slight suppression of myeloid colony formation. The significant inhibition of hematopoiesis by plasma of HIV patients could be due to the presence of active forms of TGF-. The results of the blocking experiments are consistent with the concept that TGF- in low concentrations is essential for erythropoiesis and myelopoiesis but that higher levels of TGF- primarily inhibit erythropoiesis in vitro. TGF- serves as a coordinating factor when efficient recruitment of granulocytes and monocytes is more essential than erythropoiesis and stem cell growth.Abbreviations BFU-E burst forming unit-erythroid - CFC colony forming cells - CFU-GEMM colony forming unit-granulocyte/erythroid/macrophage/megacaryocyte - CFU-GM colony forming unit-granulocyte/macrophage - EPO erythropoietin - GM-CSF granulocyte/macrophage-colony stimulating factor - HIV human immunodeficiency virus - IL-1 interleukin-1 - IL-3 interleukin-3 - IMDM Iscove's Modified Dulbecco's medium - PBS phosphate buffered saline - TGF- transforming growth factor- - TNF- tumor necrosis factor-  相似文献   

6.
Summary Neutralization tests, employing the cytopathogenic effect in tissue culture tubes, with a variety of homotypic antisera and strains of Coxsackie B viruses often yielded high titers in early readings and low titers in late readings — the break-through phenomenon — and occasionally also low, early-reading titers with heterologous, homotypic sera, which gave high titers with the homologous strains. Of 27 strains of Goxsackie B 1 to B 5, that were tested, 10 showed no break-through tendency while others showed varying degrees of break-through, without reference to any evidence of intratypic antigenic variation. There was a positive correlation between a small number of tissue culture passages away from man or mouse brain and the break-through tendency. Moreover, strains without break-through tendency yielded viral populations with marked break-through properties after a single intracerebral passage in newborn mice, and even after two subsequent tissue culture passages. Plaque-purified progeny exhibited the break-through phenomenon to the same extent as the original, unpurified cultures.The early readings yielded reproducible titers, which could be used for analysis of antigenic variation. Prime antigenic variants, of broader antigenic constitution than their non-prime relatives, were found among the Coxsackie B 2, B 3, and B 4 strains that were tested. These prime strains (e. g., B. V. A. 96- B2; Stevens - B 3, and Burrier or J. V. B. - B 4) were found to be antigenically broader than the prototype strains (Ohio 1 - B 2, Nancy - B 3, Powers or Texas 13 - B 4) generally used for the preparation of diagnostic antisera. The broader antigenicity of the prime variant was also present in plaque-purified progeny.Aided by grants from The National Foundation, Inc.The work reported here was carried out in 1957–1958 during Dr.Wigand's tenure of a fellowship in the Cincinnati Laboratory.  相似文献   

7.
Zusammenfassung Die Abstammung der-Globuline im Liquor wurde bei 20 Fällen mit den verschiedensten neurologischen Erkrankungen untersucht. — Die spezifische Aktivität der-Globuline war bei normalen und pathologischen Liquors ausnahmslos niedriger als im Serum. Es treten demnach nur einzelne Serum--Globuline in den Liquor über, ein verschieden großer Anteil der Liquor--Globuline wird im Liquorraum gebildet. Die-Fraktion im Liquor besitzt einen Serumanteil, von dem die liquoreigenen oder auch cerebrogenen-Globuline unterschieden werden können. Beziehungen zwischen der Höhe des liquoreigenen-Globulinanteils zu einzelnen Krankheitsgruppen waren nicht herzustellen. Es ließ sich aber zeigen, daß eine Erhöhung des elektrophoretisch ermittelten relativen-Globulingehaltes im Liquor bei pathologischen Fällen nicht — wie bisher angenommen wurde — mit einer Zunahme des cerebrogenen Eiweißes einherzugehen braucht. — Die Bedeutung des liquoreigenen-Globulins ist noch unbekannt, auch ist es nicht möglich zu entscheiden, welche einzelnen Proteine innerhalb der-Fraktion im Liquorraum entstanden sind oder aus dem Serum stammen.Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   

8.
The effect of interferon- (IFN-) on the interaction between tumor cells and mesothelial cell layers was studied from the aspect of changes in mesothelial permeability. Mesothelial permeability was assessed as the percentage diffusion of radiolabeled albumin across the mesothelial cell sheets on Matrigel-coated filter cup assemblies. When lined gastric carcinoma cells (KATO-III) were seeded on the confluent mesothelial cell layers, the fine cobblestone appearance of the cell sheet was disrupted and mesothelial permeability significantly increased. The increase in permeability was suppressed by the addition of as little as 1 U/ml of IFN-. The effect of IFN- was observed when either the conditioned medium of tumor cells alone or the IFN--resistant tumor cells, K-562, was placed onto the mesothelium. The cobblestone appearance of the cell sheet was relatively well preserved in the presence of IFN-. In contrast, IFN- did not suppress tumor-induced mesothelial permeability. These results suggest that IFN- has the potential to protect the human mesothelial cell layers against tumor cells.  相似文献   

9.
Summary We investigated for rearrangements of the immunoglobulin (Ig) heavy and light chain genes and of the T cell receptor (TCRT) and (TCr) genes 45 biopsy samples from a variety of lymphoproliferative disorders. They were diagnosed histopathologically and immunophenotypically as non-Hodgkin's lymphomas (NHLs) of the B cell type (19 cases), NHLs of the T cell type (3 cases), NHLs of undetermined cell type (3 cases), atypical lymphoid proliferation (1 case) and AIDS-related lymphadenopathies with florid polyclonal follicular hyperplasia (19 cases). A monoclonal proliferation of B cells was shown by DNA analysis in all 19 B cell NHLs. In two immunohistologically determined T cell NHLs (both diagnosed as mycosis fungoides) the cells had rearrangements of TCr gene, whereas in the third case (lymphoblastic NHL) the cells had rearrangements of Ig heavy chain and TCr and TCr genes. None of the B cell NHLs exhibited TCrand TCr gene rearrangement bands. All the undetermined cell NHLs demonstrated rearrangements of Ig heavy chain gene associated with the germ line TCrand TCr genes; in two cases light chain gene rearrangements were also found. The atypical lymphoid proliferation, in which the differential diagnosis was between a reactive or malignant process, and two out of 19 cases of florid polyclonal follicular hyperplasia showed a clonal B cell population by DNA analysis. This study indicates that there was a strong correlation between the rearrangements of specific genes and the immunophenotype of the NHL; moreover, DNA analysis of tissue biopsy specimens from phenotypically undetermined cell NHLs and from equivocal lymphoid proliferation using Ig and TCR gene probes yelded an answer in the cases analyzed. The significance of clonal B cell expansions found in two AIDS-related lymphadenopathies should be interpreted with caution.This work was supported in part by a Grant No 86.00644.44 from the Consiglio Nazionale delle Ricerche, Progetto Finalizzato Oncologia, Rome, and by the Associazione Italiana per la Ricerca sul Cancro, Milan, Italy  相似文献   

10.
Zusammenfassung 16-Hydroxyprogesteron, 17-Hydroxyprogesteron, 4-Pregnen-20-ol-3-on, 4-Pregnen-17, 20-diol-3-on, Adrenosteron und 11-Hydroxyandrostendion wurden in Extrakten von Plasma des menschlichen Placentablutes (Nabelschnurblut) nachgewiesen.  相似文献   

11.
Summary A new method for three-dimensional reconstruction of transmitter-identified neurons is presented which involves en bloc immunofluorescence histochemistry and confocal scanning microscopy. The technique was applied to different types of neurons in the rat brain and lamprey spinal cord. Thick sections or tissue blocs (50–200 m thick) were incubated with antisera against neuropeptides or monoaminergic markers, followed by fluorescent secondary antibodies. Three-dimensional reconstructions were obtained by scanning the preparations in sequential focal planes with a thin laser beam, while sampling the emitted light in each focal plane. The method is convenient and can be applied to a wide variety of neuron types. The reconstructions obtained are accurate since the optical serial sections of the specimen are perfectly aligned, and optic disturbances such as halo phenomena do not occur.  相似文献   

12.
Zusammenfassung Bergsteigen in großen Höhen führt nur zu einer relativ geringen Energieumsatzsteigerung gegenüber dem Grundumsatzsollwert verglichen mit anderen Sportarten. Die Ursache dafür liegt anscheinend in der geringen Aufstiegsgeschwindigkeit, die einerseits durch die Ökonomie des Bergsteigens, andererseits durch die natürliche Begrenzung der Sauerstoffversorgung bedingt ist.
Summary Climbing in high altitude leads to little increase of energy expenditure in relation with basic metabolism compared with other types of sport. Perhaps that is caused by the relatively slow speed of climbing limited on the one side by the economy of climbing (housekeeping) on the other one by the natural limitation of oxygen supply.
  相似文献   

13.
Summary In rabbits and their progeny an investigation was made of summation and adaptation of the neurones of the motor cortex; unipolar stimulation was used, and the muscular response recorded. Two types of summation curves were found: exponential and Y-shaped,, and were related to the direct and indirect summation of stimulation. In adults, Y-shaped summation curves were more frequent, whereas in rabbits aged 24 h exponential curves preponderted. We found very little capacity for adaptation at any age.(Presented by Active Member AMN SSSR A. F. Turom) Translated from Byulleten Éksperimental'noi Biologii i Medisiny, Vol. 55, No. 6, pp. 3–7, June, 1963  相似文献   

14.
Fatigue has been acknowledged as a widespread problem associated with a variety of factors. In the present paper, we attempt to explain fatigue complaints on the basis of Pennebaker's (1982) competition of cues notion. Competition of cues suggests that both extremely low and extremely high levels of external stimulation in daily life may be related to relatively higher frequencies of complaint. The dimensional structure of external stimulation is first explored and then the shape of the relation between external stimulation (i.e., stimuli perceived in daily life) and fatigue was studied in a sample of 777 general-practice patients. Other risk factors for fatigue and moderating factors are also taken into consideration. Results show that quantity and quality of external stimulation can be distinguished. Both high quantity (high experienced overload) and low quality (low attractiveness of external stimulation) are related to higher fatigue frequencies. Experienced overload is a particularly strong predictor, in addition to perceived health of fatigue complaints. It is concluded that the quality-quantity model for understanding fatigue proposed here highlights psychological factors important for any theoretical framework of fatigue.  相似文献   

15.
In vitro susceptibility tests were performed with 350 selected strains ofStreptococcus pneumoniae to evaluate disk diffusion tests with 30 g and 1 g cefotaxime disks. Zones were compared to MICs of cefotaxime with and without its desacetyl metabolite. Cefotaxime was two to eight times more active than desacetyl cefotaxime, but the two compounds were additive when combined in vitro. For 30 g disks, zone size breakpoints were 27 mm, 28–30 mm and 31 mm for resistant, intermediate and susceptible, respectively. For 1 g disks, those zone size criteria were reduced to 13 mm, 14–16 mm and 17 mm. The 30 g disk that is currently available for testing other species can be used for testing pneumococci; however, the 1 g disk has some important advantages.  相似文献   

16.
Zusammenfassung 1. Vergleichende Messungen des Herzzeitvolumens mit der thermodilution-Methode, nach dem Fickschen Prinzip und mit dem Farbstoff-Verdünnungs-Verfahren zeigten gute Übereinstimmung und bewiesen die Brauchbarkeit der thermo-dilution-Methode.2. Die Versuche ergaben weiterhin, daß die Herzzeitvolumen-Bestimmung mit der thermo-dilution-Methode auch am unnarkotisierten Tier möglich ist.Mit 4 Textabbildungen  相似文献   

17.
The 5S ribosomal (r) RNA genes encode a small (120-bp) highly-conserved component of the large ribosomal subunit. The objective of the present research was to study the molecular and cytogenetic organization of the chicken 5S rDNA. A predominant 2.2-kb gene (5S) consisting of a coding and intergenic spacer (IGS) region was identified in ten research and commercial populations. A variant gene repeat of 0.6kb (5S) was observed in some of the populations. Genetic linkage analysis and cytogenetic localization by fluorescence in-situ hybridization assigned the 5S rDNA to chromosome 9. The 5S rDNA array was determined to be 80.2±7.0kb upon electrophoretic sizing following EcoRV digestion. Sequence analysis of 5S IGS regions revealed considerable conservation between chicken subspecies (98.4% identity) as well as homology with vertebrate Pol III promoter and regulatory sequence motifs. Minor intraindividual sequence variation within 1000bp of IGS was observed in four cloned Red Jungle Fowl (Gallus gallus gallus) 5S repeats (95.5% identity in this region). Sequence comparisons between IGS regions of 5S and 5S genes indicated two short continuous (>20bp) and many short non-continuous homologous regions as well as other conserved features such as promoter and termination motifs.  相似文献   

18.
Summary The rice chloroplast genome has been derived from a tobacco-like ancestral form by three major inversions. In the rice genome we have found six pseudogenes, trnG, trnI, 3-rps 12a, trnT, trnE and trnfM/G, all located near inversion endpoints, as well as four short repeated sequences. A comparison of rice, wheat and tobacco sequences indicated that similar pseudogenes are present in wheat but not in tobacco, suggesting that the creation of these pseudogenes occurred before the divergence of rice and wheat. The region downstream of rbcL is a variable region and contains rpl23 in rice and wheat and another 3-rps 12b further downstream in rice. This 3-rps 12b shows a higher homology to the functional rps 12 than 3-rps 12a, which suggests that it appeared more recently. The involvement of these pseudogenes in genome inversions and the creation of the pseudogenes and short repeated sequences are discussed.  相似文献   

19.
The inhibitory activity of eight antibiotics and the inhibitory and bactericidal activities of combinations of trimethoprim/sulfamethoxazole (TMP/SMX) plus three fixed concentrations of polymyxin B (0.01 g/ml, 0.1 g/ml and 0.5 g/ml) against 30 multiresistant strains ofStenotrophomonas maltophilia were tested. Polymyxin B at 0.01 g/ml modified the inhibitory activity of TMP/SMX against only 40% of strains. At 0.1 g/ml and 0.5 g/ml, polymyxin B enhanced the inhibitory activity of TMP/SMX activity against all strains. Polymyxin B enhanced the bactericidal activity of TMP/SMX only at concentrations near the minimum inhibitory concentration of polymyxin B alone.  相似文献   

20.
Summary Neuronal activity was studied in the premotor cortex (PM) of two rhesus monkeys, each of which performed both forelimb and hindlimb movements. On each trial, the monkey received a visual instruction stimulus (IS) that indicated whether a foot or a hand movement would be rewarded on that trial. After a delay period, during which the monkey withheld an overt movement, a visual trigger stimulus (TS) was presented to indicate that the monkey should execute a movement. Of 572 task-related neurons recorded in PM, 149 neurons showed set-related activity, defined as a significant increase or decrease in discharge rate throughout most of the instructed delay period, and 299 neurons showed movement-related activity, defined as a significant change in discharge rate between the TS and movement onset. Both setand movement-related activity were subdivided into three patterns: activity modulation 1) before a foot movement only (foot neurons); 2) before a hand movement only (hand neurons); and 3) before both foot and hand movements (mixed neurons). The distribution of set-related neurons mostly overlapped with that of movement-related neurons, although set-related neurons were located in more restricted regions than movement-related neurons. Foot neurons with setand movementrelated activity were distributed near the superior precentral sulcus. Hand neurons were mainly located lateral to the foot neurons with some overlap. The results indicate that most PM setand movement-related neurons contribute, respectively, to the preparation for and execution of specific limb movements, as opposed to movement per se. Further, the differential distribution of neurons with activity related to hindlimb vs. forelimb movement supports previous indications that PM is topographically organized.  相似文献   

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