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排序方式: 共有1039条查询结果,搜索用时 15 毫秒
1.
Summary The frequency of large granular lymphocytes (LGL) in the peripheral blood of healthy persons (n=56) and breast cancer patients (31 cases with stage-I and -II disease and 42 cases with stage-III and -IV disease) was studied. The frequency of LGL in peripheral blood was significantly depressed in cancer patients, and particularly in patients with advanced breast cancer. 相似文献
2.
F Krizsa Z Borbényi E Arokszállásy I Cserháti 《Folia haematologica (Leipzig, Germany : 1928)》1980,107(4):683-687
The thrombopoietic serum activity was examined in rats during thrombocytopenia produced by bleeding or after treatment with antithrombocyte serum (ATS). 6 hours after both treatments the thrombopoietic activity of the serum, i.e. its content of thrombopoietin, is increased. After the ATS treatment of nephrectomized animals a similar increase of thrombopoietic activity as in normal animals could be achieved. In contrast to that, no similar increase of thrombopoietic activity was observed in nephrectomized animals after blood loss. According to the results of the authors the increase of thrombopoietic activity produced by different stimuli can be attributed to different mechanisms. 相似文献
3.
Tibor Kiss 《Invertebrate neuroscience : IN》2017,17(3):9
Having been investigated for over 40 years, some aspects of the biology of terrestrial gastropod’s olfactory system have been challenging and highly contentious, while others still remain unresolved. For example, a number of terrestrial gastropod species can track the odor of food, while others have no strong preferences toward food odor; rather they find it by random encounter. Here, while assessing the most recent findings and comparing them with earlier studies, the aspects of the food selection based on olfactory cues are examined critically to highlight the speculations and controversies that have arisen. We analyzed and compared the potential role of airborne odors in the feeding behavior of several terrestrial gastropod species. The available results indicate that in the foraging of most of the terrestrial gastropod species odor cues contribute substantially to food finding and selection. The results also suggest, however, that what they will actually consume largely depends on where they live and the species of gastropod that they are. Due to the voluminous literature relevant to this object, this review is not intended to be exhaustive. Instead, I selected what I consider to be the most important or critical in studies regarding the role of the olfaction in feeding of terrestrial gastropods. 相似文献
4.
5.
Tibor Hortobagyi Frank I. Katch Peter F. LaChance 《European journal of applied physiology and occupational physiology》1989,58(7):749-755
Two studies were conducted in 83 college men to determine the degree of generality of individual differences in upper body muscular strength assessed by different testing modes. In study 1 (N = 43), correlations were computed between four measures of upper body strength using the bench press movement, maximal isokinetic (0.09 rad.s-1), maximal fast (0.126 m.s-1) and slow (0.037 m.s-1) hydraulic, and one repetition maximum (1-RM) free weight bench press (BP). Compared to free weight BP, maximal strength during isokinetic and slow hydraulic BP was approximately 29% and approximately 8% larger, and fast hydraulic BP strength was approximately 63% lower (p less than 0.05). Simple linear regression of isokinetic BP on 1-RM BP yielded r = 0.79, error of prediction (SE) = 12%, and generality = 81%. The corresponding averaged values for the regression of slow and fast hydraulic BP on free weight 1-RM BP were r = 0.77, SE = 13.5%, and generality = 84%. In Study 2 (N = 40), testing included maximal isokinetic concentric and eccentric arm flexion and extension at 0.524, 1.570, and 2.094 rad.s-1. The ratio of concentric to eccentric torque at the 3 speeds averaged 0.68 (flexion) and 0.70 (extension), and eccentric torques were 32% and 30% greater than concentric torques (p less than 0.05). The linear regression between concentric vs. eccentric flexion and extension torques at the three velocities yielded an average r = 0.80, SE = 13.7%, and generality = 73%.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Gerd Wallukat Gyorgy Nemecz Tibor Farkas Hartmut Kuehn Albert Wollenberger 《Molecular and cellular biochemistry》1991,102(1):35-47
Incubation of rocker-cultured neonatal rat heart cells with 3 mM L(+)-lactate led to a sharp increase in the sensitivity of cardiomyocytes to the beta-adrenergic agonist isoprenaline, as measured by their chronotropic response. This effect was accompanied by a reduction in the arachidonic acid content of the total phospholipids. The phospholipase A2-activator melittin as well as free arachidonic acid induced this supersensitivity to the same degree. On the other hand, the L(+)-lactate-evoked supersensitivity could be blocked by the phospholipase A2 inhibitors mepacrine and n-bromophenacyl-bromide, suggesting an involvement of phospholipase A2 in the process of beta-adrenergic sensitization. The sensitizing action of arachidonic acid was blocked by the lipoxygenase inhibitors esculetin and nordihydroguaiaretic acid, but not by the cyclooxygenase inhibitor indomethacin. Supersensitivity was likewise evoked by 15-S-hydroxyeicosatetraenoic acid (15-S-HETE), but not by 5-S-HPETE or 5-S-HETE. These findings suggest that the phospholipase A2-15-lipoxygenase pathway plays a role in the induction of beta-adrenergic supersensitivity in the cultured cardiomyocytes and point to a new physiological role of the lipoxygenase product 15-S-HETE.Abbreviations NDGA
nordihydroguaiaretic acid
- HETE
hydroeicosatetraenoic acid
- HPETE
hydroperoxyeicosatetraenoic acid 相似文献
7.
Taurine Levels in Discrete Brain Nuclei of Rats 总被引:7,自引:1,他引:6
Miklós Palkovits István Elekes Tibor Láng rás Patthy 《Journal of neurochemistry》1986,47(5):1333-1335
Concentrations of taurine have been measured in 44 microdissected rat brain nuclei or areas. Taurine is ubiquitously present and distributed unevenly in the rat brain: the ratio of the highest (pyriform cortex) to lowest (midbrain reticular formation) concentrations is 4.7:1. High taurine levels were found in cerebral cortical areas, caudate-putamen, cerebellum, median eminence, and supraoptic nucleus. Acute pain stress reduced taurine levels in the hypothalamus and the lower brainstem nuclei but not in cortical areas. Increased locomotor and behavioral activities following a high dose of amphetamine elevated taurine concentrations significantly in the substantia nigra and locus ceruleus. 相似文献
8.
Principal component analysis for a better understanding of the herbicidal effectivity of some benzonitriles 总被引:1,自引:0,他引:1
To gain more insight in mode of action of ten different 4-hydroxy-benzonitrile derivatives, their biological activities in eight bioassays, and their lipophilicity and adsorptivity determined by thin-layer chromatography in nine different systems were subjected to principal component analysis. Four background components explained about 90% of total variance. Only three of eight biological activities, the inhibition of the 2,6-dichlorophenol-indophenol reduction by spinach and wheat chloroplasts and the CO2 fixation of wheat seedlings had not any common background components with the physico-chemical parameters of the compounds. The nonlinear mapping of principal component loadings and variables showed, that the in vivo and in vitro biological activities differed considerably and depended on the object investigated. The effectivity of compounds is governed mainly by the number of substituents and by the presence of free hydroxy group. 相似文献
9.
Tibor Benedek 《Mycopathologia》1967,31(2):81-143
Summary The discovery of the hidden, built-in macroconidia in the four members of the Faviform Group of the dermatophytes, i.e.,Achorion schoenleinii, Trichophyton violaceum, Trichophyton verrucosum andMicrosporon ferrugineum, is described.To bring the hidden, built-in macroconidia to full fructification, i.e., to force the production of imperfect and perfect organs of fructification (macroconidia, cleistothecia), two entirely different techniques have been used: 1) the hair-soil method, 2) the yeast extract method.The two techniques, entirely independent from each other, yielded the same result: the ancestral form of the four members of the Faviform Group of dermatophytes. The imperfect form is described asFavomicrosporon pinettii,Benedek, 1965, sp. nov. The perfect form isAnixiopsis stercoraria (Hansen)Hansen, 1897.The ancestral form was found not only in and cultured from the strains of those dermatophytes derived from pathological material, but it was also recovered from its saprophytic habitat, from the soil (potting soil).
Zusammenfassung Die Entdeckung der verborgenen, eingebauten Makrokonidien in den vier Representanten der Faviformen Gruppe der Dermatophyten, i.e.Achorion schoenleinii, T. violaceum, T. verrucosum, Microsporon ferrugineum, wird beschrieben.Um die verborgenen, eingebauten Makrokonidien zur vollen Fruchtbildung zu bringen, i.e. um die Produktion der imperfekten und perfekten Organe der Fruktifikation (Makrokonidien, Kleistothecien) zu erzwingen, sind zwei völlig verschiedene Methoden benutzt worden: 1) die Haar-Erde-Methode, und 2) die Hefeextrakt-Methode.Beide Methoden, völlig unabhängig von einander, haben zu demselben Ergebnis geführt, i.e. zur Entdeckung der Urform von den vier Representanten der Faviformen Gruppe der Dermatophyten. Die imperfekte Form wird alsFavomicrosporon pinettii,Benedek, 1965, sp. nov. beschrieben. Die perfekte Form istAnixiopsis stercoraria (Hansen)Hansen, 1897.Die ancestrale Form wurde nicht nur aus den Stämmen jener Dermatophyten gezüchtet, die aus pathologischen Produkten gewonnen worden sind, sondern auch aus dem natürlichen Habitat: von der Erde (potting soil).
Résumé La découverte des macroconidies occultes et encastrées dans les quatre membres du Groupe Faviforme des dermatophytes:Achorion schoenleinii, Trichophyton violaceum, Trichophyton verrucosum etMicrosporon ferrugineum, est décrite.Pour forcer les macroconidies occultes et encastrées à la fructification complète, i.e. de produire des organs de reproduction imparfaits et parfaits, macroconidies et cleistothecia, on a fait l'usage de deux techniques complètement différentes: 1) des cheveux sur sol et 2) de l'extraction de levure.Toutes les deux méthodes, complètement indépendantes l'une de l'autre, ont produit le même résultat: la forme ancestrale des quatre membres de la Groupe Faviforme des dermatophytes. La forme imparfaite est décrite commeFavomicrosporon pinettii,Benedek, 1965, sp. nov. et la forme parfaite commeAnixiopsis stercoraria (Hansen)Hansen, 1897.La forme ancestrale a été trouvée non seulement dans les souches des dermatophytes indiquées et en cultivées, provenantes des produits pathologiques, mais aussi du sol, du terrain jardinier.相似文献
10.
The role of glucocorticoids in the modulation of central alpha 2-receptor mechanisms was investigated by in vitro receptor binding studies. [3H]Clonidine and [3H]idazoxan were used as radioligands. The alpha 2-receptor subtypes and guanine nucleotide sensitivity were studied in homologue and heterologue displacement experiments following hydrocortisone treatment (25 mg/kg s.c.) for 10 days. High and low agonist affinity states of the alpha 2-receptor could be identified in 3H-antagonist-agonist and 3H-agonist-antagonist displacement experiments, which may correspond to different regulatory protein-nucleotide associated forms of the receptor. In the presence of 10 microM GTP, the high-affinity binding was depressed. Following hydrocortisone treatment, there was no detectable change either in the affinity or the binding site concentration of clonidine in homologue displacement ("cold saturation") experiments. The affinity of idazoxan, however, was depressed. The effect of GTP was similar to the controls in this experimental arrangement. In contrast, in heterologue binding studies the high-affinity binding site was not demonstrable and the amount of low-affinity binding increased following the hydrocortisone treatment. The high-affinity site reappeared in the presence of GTP. The change in GTP sensitivity suggests that the nucleotide regulatory system may be involved in the action of adrenal steroids on central alpha 2-receptoral mechanisms. 相似文献