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101.
M.D. J.J. Amy M.D. M. Dierick M.D. Ph.D. M. Thiery M.D. A. Remouchamps 《Prostaglandins & other lipid mediators》1975,10(4):395-403
Present study was prompted by the report from another center on the occasional occurrence of convulsions and abnormal electroencephalogram (E.E.G.) patterns in women aborted with intraamniotic prostaglandin F2α (PGF2α). Fifty four subjects were investigated by means of an E.E.G. taken before and after initiation of PGE2 administration. They included pregnant and non-pregnant patients, nearly half (23) of whom were known epileptics. One seizure was observed during PG administration in a man with daily psychomotor attacks who had not taken his anticonvulsants on the day the test was performed. PGE2 caused no alteration of the E.E.G. in subjects with a normal control tracing; in those with an abnormal E.E.G., a deterioration was seen in one and an improvement in three. It is concluded that PGE2 is not epileptogenic at doses required for termination of pregnancy. 相似文献
102.
Induction of tumoricidal activity is one of the major functions of activated macrophages. Our previous study demonstrated that P388D1 murine macrophage-like cells secreted a plasmacytoma cytotoxic factor (PCF) that selectively killed certain tumor cell lines including MOPC-315 plasmacytoma in vitro. Our subsequent studies demonstrated that PCF killed MOPC-315 cells by induction of apoptosis. In this report, the involvement of Fas and Fas ligand (FasL) in PCF-induced apoptosis was investigated. Results suggest that expression of Fas mRNA time-dependently increased in PCF-treated cells and reached an optimal level after 36 h of treatment. The augmented effect of PCF on Fas mRNA expression was significantly reduced by the addition of CB7.C2, an anti-PCF monoclonal antibody. The expression of FasL mRNA was also induced by PCF and reached an optimal level at 24 h, but sharply decreased after 36 h of treatment. Caspase-3 is one of the proteolytic enzymes that can be activated by the Fas-FasL interaction. In our studies, the enzymatic activity of caspase-3 was significantly induced by PCF after 6 h of treatment and reached an optimal level at 12 h. The augmented effect of PCF on caspase activity was significantly reduced by the addition of CB7.C2 and the caspase-3-specific inhibitor, DEVD-fmk. Therefore, PCF-treated plasmacytoma cells might undergo apoptosis via interaction between Fas and FasL. 相似文献
103.
Uric Acid Amplifies Aβ Amyloid Effects Involved in the Cognitive Dysfunction/Dementia: Evidences From an Experimental Model In Vitro
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104.
Expression of cell type-specific markers during pancreatic development in the mouse: implications for pancreatic cell lineages 总被引:2,自引:0,他引:2
Summary The islet cells of the mammalian pancreas are comprised of four different endocrine cell types, each containing a specific hormone. Islet cells also contain two enzymes of the catecholamine biosynthetic pathway: tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC). The cell lineage relationships of these different cell types have not been examined and it is not known whether, during development, they originate from the same or from different precursor populations. In this study we used immunocytochemical procedures to determine whether developing pancreatic cells express markers common to endocrine and exocrine cell types. We found that acinar cell precursors express AADC prior to the appearance of an exocrine marker and that the expression of AADC in acinar cells persists throughout embryogenesis to the first month of postnatal life. At this time, acinar cells do not contain AADC. We also found that exocrine cells containing AADC never express other islet-cell markers. These findings suggest that while acinar and islet cells both arise from precursor cells containing AADC, these progenitor cells do not express a combined endocrine-exocrine phenotype. 相似文献
105.
This paper provides quantitative information concerning the response of ostracods to environmental variability in order to reconstruct past environments. Ostracod faunas from modern sediments of Bolivian lakes and swamps were studied. Ostracod distribution is controlled by several ecological characteristics such as lake-level and water chemistry. Statistical results indicate that three transfer functions (on water depth, Total dissolved Salts and water in Mg/Ca ratio) can be developed, from ostracod species frequencies in lacustrine sediments, with some restrictions for the two last ones. 相似文献
106.
Ph. D. Mordukhay-Boltovskoy 《Hydrobiologia》1964,23(1-2):159-164
Summary There are about 335 species belonging to the autochthonous Caspian complex and dwelling in the basin of the Caspian, Black, and Asov seas.Not less than 22 species of this complex are known at present beyond the boundaries of the Ponto-Caspian basin. Most of them (15 species) have emigrated from this basin recently. Some fishes and two invertebrates penetrated into the Mediterranean or even into the oceans via the seas. Other species penetrated into fresh waters of the basin of the Baltic Sea and the Atlantic ocean (and partly of the Arctic seas) doubtless via the natural or artificial( canals) connections between the river-systems of adjacent basins.Remarkably the caspian species which immigrated into the Baltic basin turn out to be very viable, develop in great quantities and depress even some indigenous species. As some of them appeared in the Baltic basin during the last decades and the process of spreading of the Caspian fauna goes on, the intrusion of some more Caspian species may be awaited.There are, however, 6 or 7 species of Caspian origin, dwelling in isolated lakes of Asia Minor or the Balkan peninsula, probably relicts of the ancient (Tertiary?) transgressions of the Pont, what is confirmed by their taxonomic differentiation.Only two Caspian species reached the western hemisphere till now (Cordylophora caspia, Victorella pavida).
Zusammenfassung Im Bassin der Kaspischen, Schwarzen und Asowschen Meere leben ca. 335 dem autochthonen Kaspischen Komplex angehörende Arten.Zur Zeit sind nicht weniger als 22 Arten dieses kaspischen Komplexes ausserhalb der Grenzen des Pontokaspischen Bassins bekannt. Von ihnen sind 15 Arten in der allerletzten Zeit aus diesem Bassin ausgewandert. Einige Fischarten und zwei Wirbellose sind auf Seewegen in das Mittelmeer oder sogar in Ozeane gelangt. Andere Arten sind in die Süsswasser des Baltischen und Atlantischen (teilweise auch des Arktischen) Bassins zweifellos mittels der natürlichen oder künstlichen (Kanäle) Verbindungen zwischen den Flussystemen eingedrungen.Merkwürdigerweise erweisen sich die ins Baltische Bassin eingedrungenen kaspischen Arten als sehr lebensfähig, vermehren sich in grosser Anzahl und verdrängen sogar einige einheimische Tierarten. Da einige von ihnen im Baltischen Bassin erst in den letzten Jahrzehnten erschienen sind und da die Verbreitung der kaspischen Fauna sich immer weiter erstreckt, sind weitere Invasionen neuer kaspischer Arten zu erwarten.Es gibt aber 6–7 Arten kaspischer Herkunft, die in isolierten Seen Kleinasiens und der Balkanhalbinsel wohnen und wahrscheinlich den Relikten der älteren (tertiären?) Transgressionen des Pont zuzuzählen sind, was auch durch ihre taxonomische Absonderung ersichtlich ist.Nur zwei kaspische Arten (Cordylophora caspia, Victorella pavida) haben bisher die westliche Halbkugel erreicht.相似文献
107.
Elizabeth H. O'Hern Ph. D. 《Mycopathologia》1964,22(2):167-174
Summary 1. A variant strain ofHistoplasma capsulatum was isolated from a secondary colony in cultures of tissue from hamsters infected with the parent strain ofHistoplasma. The variant strain was found to differ from the parent strain in colonial morphology, stability of the yeast phase in subculture, and in growth rate.2. Results of virulence testing with these two strains showed the parent strain to be somewhat more virulent than the variant strain as measured by survival time and slope of the death rate curve over a 19 day period.3. Nevertheless, in view of the more rapid growth rate of the variant and its probable antigenic variation from the parent strain, the development of such a variant is viewed as an increased hazard to the host, particularly in a longer term infection.4. The repeated isolation of a variant strain ofHistoplasma suggests that strain variation may play a significant role in the outcome of naturally acquired infections.This work was initiated at the State University of New York, Downstate Medical Center, Brooklyn, N. Y., and supported in part by funds ((#12-1081) from the National Fund for Medical Education, grant # 12-1054. 相似文献
108.
Summary Species ofChrysosporium have been isolated from soil in Iran. Guinea pigs inoculated withChrysosporium keratinophilum gave a positive skin test to histoplasmin and vice versa. This would suggest thatChrysosporium species might be reponsible for positive skin tests to histoplasmin in areas known not to be endemic for histoplasmosis. 相似文献
109.
110.