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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.
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
3.
Lee D. Major Thomas S. Partridge Joy Gardner Stephen J. Kent Robert de Rose Andreas Suhrbier Wayne A. Schroder 《PloS one》2013,8(2)
SerpinB2, also known as plasminogen activator inhibitor type 2, is a major product of activated monocytes/macrophages and is often strongly induced during infection and inflammation; however, its physiological function remains somewhat elusive. Herein we show that SerpinB2 is induced in peripheral blood mononuclear cells following infection of pigtail macaques with CCR5-utilizing (macrophage-tropic) SIVmac239, but not the rapidly pathogenic CXCR4-utilizing (T cell-tropic) SHIVmn229. To investigate the role of SerpinB2 in lentiviral infections, SerpinB2−/− mice were infected with EcoHIV, a chimeric HIV in which HIV gp120 has been replaced with gp80 from ecotropic murine leukemia virus. EcoHIV infected SerpinB2−/− mice produced significantly lower anti-gag IgG1 antibody titres than infected SerpinB2+/+ mice, and showed slightly delayed clearance of EcoHIV. Analyses of published microarray studies showed significantly higher levels of SerpinB2 mRNA in monocytes from HIV-1 infected patients when compared with uninfected controls, as well as a significant negative correlation between SerpinB2 and T-bet mRNA levels in peripheral blood mononuclear cells. These data illustrate that SerpinB2 can be induced by lentiviral infection in vivo and support the emerging notion that a physiological role of SerpinB2 is modulation of Th1/Th2 responses. 相似文献
4.
5.
P P Major P E Kovac M L Lavallée E C Kovalik 《The journal of histochemistry and cytochemistry》1987,35(2):139-148
We report the production, screening, and characterization of ten murine monoclonal antibodies directed at antigens that are expressed abnormally in human breast tumors. Immunoperoxidase staining of frozen and fixed tissues shows the antigens to be present at low levels on the luminal membrane of normal breast cells and at high levels in the cytoplasm and surface membrane of breast tumor cells. The ten antibodies appear to recognize six different epitopes on the basis of their quantitative differences in reactivity against four antigen preparations, as measured by ELISA. Immunoblots show that eight of the ten antibodies recognize a 300,000 MW molecule from breast tumor preparations; six of these antibodies also react with a second molecule from the same tumor preparations of 280,000 MW. Seven antibodies react with an antigen from milk fat globule membrane of 330,000 MW. It therefore appears that the two molecules from tumor tissue and the one molecule from normal tissue share common epitopes. Selected antibodies were tested for reactivity against 25 primary breast tumors and 14 pairs of primary and metastatic breast tumors. Three antibodies have broad reactivity and stain more than 80% of primary tumors; the three other antibodies identify subsets of those tumors. Results of staining pairs of primary and metastatic lesions show that metastases continue to express antigens of the primary lesion in a high percentage of cells. 相似文献
6.
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
7.
Purification to homogeneity and partial amino acid sequence of a fragment which includes the methyl acceptor site of the human DNA repair protein for O6-methylguanine. 总被引:1,自引:1,他引:0
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DNA repair by O6-methylguanine-DNA methyltransferase (O6-MT) is accomplished by removal by the enzyme of the methyl group from premutagenic O6-methylguanine-DNA, thereby restoring native guanine in DNA. The methyl group is transferred to an acceptor site cysteine thiol group in the enzyme, which causes the irreversible inactivation of O6-MT. We detected a variety of different forms of the methylated, inactivated enzyme in crude extracts of human spleen of molecular weights higher and lower than the usually observed 21-24kDa for the human O6-MT. Several apparent fragments of the methylated form of the protein were purified to homogeneity following reaction of partially-purified extract enzyme with O6-[3H-CH3]methylguanine-DNA substrate. One of these fragments yielded amino acid sequence information spanning fifteen residues, which was identified as probably belonging to human methyltransferase by virtue of both its significant sequence homology to three procaryote forms of O6-MT encoded by the ada, ogt (both from E. coli) and dat (B. subtilis) genes, and sequence position of the radiolabelled methyl group which matched the position of the conserved procaryote methyl acceptor site cysteine residue. Statistical prediction of secondary structure indicated good homologies between the human fragment and corresponding regions of the constitutive form of O6-MT in procaryotes (ogt and dat gene products), but not with the inducible ada protein, indicating the possibility that we had obtained partial amino acid sequence for a non-inducible form of the human enzyme. The identity of the fragment sequence as belonging to human methyltransferase was more recently confirmed by comparison with cDNA-derived amino acid sequence from the cloned human O6-MT gene from HeLa cells (1). The two sequences compared well, with only three out of fifteen amino acids being different (and two of them by only one nucleotide in each codon). 相似文献
8.
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
9.
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
10.
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