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1.
The existence of duodeno-gastric reflux was evaluated in a group of 15 healthy subjects, in fasting and for 24 hours. The assessment of duodeno-gastric reflux was made by quantitation of the bile acids (BA) present in the gastric juice. The individual free and conjugated BA were separated and quantified by means of thin-layer chromatography and in situ spectrofluorometry. In 7 of the subjects studied no BA were detected, and in the other 8 subjects the BA levels were below 6 mumol reflux/hour. There were no free BA detected in any of the subjects. The levels of BA in gastric juice increased progressively with age, but there were no differences between sex. The chromatographic technique used is highly sensitive for the analysis of BA in biological samples. The study of BA in the gastric juice provides a quantitative and reliable assessment of the degree of duodeno-gastric reflux.  相似文献   
2.
The antiproliferative effect of 10(-6) M antiestrogens in an estrogen receptor-negative lymphoid cell line (K36) was enhanced in lipoprotein-poor growth medium. The enhancement was not due to increased bioavailability because cellular uptake of [3H]tamoxifen was not increased and the lipoprotein fraction of serum had negligible [3H]tamoxifen-binding capacity. Cholesterol and lipoproteins, but not mevalonate, reversed the cytostatic effect of antiestrogens. Reversal by cholesterol was dose-related (10(-7) M to 10(-5) M), while that by lipoproteins could also be demonstrated in medium undepleted of lipoproteins. The cytostatic efficacy of a series of ten compounds correlated well with their relative binding affinities for solubilized antiestrogen-binding sites from K36 cells when log IC50 values (concentration required to reduce [3H]thymidine incorporation by 50%) were plotted against log RBA50 values (concentration required to reduce [3H]tamoxifen binding by 50%) (correlation coefficient 0.94). Transmission electron microscopy of antiestrogen-treated cells showed evidence of disordered cytokinesis which was partially reversed by cholesterol. These observations implicate the antiestrogen-binding protein in the antiproliferative effect of antiestrogens in nonestrogen target cells.  相似文献   
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4.
Factor H is a major regulatory protein of the complement system. The complete cDNA coding sequence has been derived from overlapping clones, and a polymorphism at base 1277 has been characterized. In four clones there is a T at nucleotide 1277 and in two others there is a C. This T/C change represents a tyrosine/histidine polymorphism at position 384 in the derived amino acid sequence. Protein sequence studies on peptides generated by trypsin digestion of factor H, purified from pooled plasma from 12 donors, confirmed the presence of both tyrosine and histidine at this position. Tyrosine and histidine were observed in a ratio of 2 : 1, respectively, and therefore this polymorphism is likely to represent a sequence difference between the two most abundant charge variants, FH1 and FH2, of factor H.  相似文献   
5.
Single- (whole-cell patch) and two-electrode voltage-clamp techniques were used to measure transient (Ifast) and sustained (Islow) calcium currents, linear capacitance, and slow, voltage-dependent charge movements in freshly dissociated fibers of the flexor digitorum brevis (FDB) muscle of rats of various postnatal ages. Peak Ifast was largest in FDB fibers of neonatal (1-5 d) rats, having a magnitude in 10 mM external Ca of 1.4 +/- 0.9 pA/pF (mean +/- SD; current normalized by linear fiber capacitance). Peak Ifast was smaller in FDB fibers of older animals, and by approximately 3 wk postnatal, it was so small as to be unmeasurable. By contrast, the magnitudes of Islow and charge movement increased substantially during postnatal development. Peak Islow was 3.6 +/- 2.5 pA/pF in FDB fibers of 1-5-d rats and increased to 16.4 +/- 6.5 pA/pF in 45-50-d-old rats; for these same two age groups, Qmax, the total mobile charge measurable as charge movement, was 6.0 +/- 1.7 and 23.8 +/- 4.0 nC/microF, respectively. As both Islow and charge movement are thought to arise in the transverse-tubular system, linear capacitance normalized by the area of fiber surface was determined as an indirect measure of the membrane area of the t-system relative to that of the fiber surface. This parameter increased from 1.5 +/- 0.2 microF/cm2 in 2-d fibers to 2.9 +/- 0.4 microF/cm2 in 44-d fibers. The increases in peak Islow, Qmax, and normalized linear capacitance all had similar time courses. Although the function of Islow is unknown, the substantial postnatal increase in its magnitude suggests that it plays an important role in the physiology of skeletal muscle.  相似文献   
6.
Summary An integrated system for the collection, treatment and utilisation of piggery wastewater has been developed in Singapore which uses the cultivation of microalgae in high rate ponds to achieve reduction of BOD5 and COD5 of the effluent as well as producing single cell protein. A wide range of algal flora occurs in the ponds;Oocystis, Micratinium, Scenedesmus, Ankistrodesmus, Chlorella andOscillatoria spp were identified. Total algal counts, recorded from 1979 to 1981, ranged up to 107 per ml of pond water. There were considerable variations in the algal population and in the predominating species. No discernible pattern was evident. Consequently pond operations were frequently disturbed by these fluctuations in population which in turn was attributed to the heterogeneous composition of the piggery waste, to variable weather conditions and to predation by larger organisms particularlyMoina. After passing through the ponds, the total suspended solids were removed by a novel dissolved air flotation method which gave a clear effluent showing an 87% reduction in BOD5 value.
Resumen En Singapur se ha desrrollado un sistema integrado para le recogida, tratamiento y utilización de aguas residuales de pocilgas. Este sistema usa el cultivo de microalgas en estanques, de caudal rápido afin de reducir las DBO5 y DCO5 del efluencte produciendo asimismo proteínas celulares. La flora de algas producida en estos estanques es amplia y variada, habiendose identificado:Oocystis, Micratinium, Scenesdemus, Ankistrodesmus, Chlorella y Oscillatoria. Los recuentos totales de algas tomados desde 1979 a 1981 llegaron a alcanzar 10;7 por ml de agua del estanque. Se observaron variaciones considerables tanto en la población total de algas como en las especies predominantes sin que se pudiese, determinar un patrón de variación característico. Estas fluctuaciones en la población, causantes de frecuentes alteraciones en el funcionamiento del estanque, se atribuyeron a la composición heterogenea de los resuduos, a las variaciones climáticas y la predación por otros organismos particularmenteMoina Después de su paso por los estanque los solidos suspendidos totales se eliminaron mediante un nuevo método de flotación con aire disuelto, obteniendose un efluente limpio con una reducción de la DBO5 del 87%.

Résumé Un système intégré pour la collecte, le traitement et l'utilisation d'eaux résiduaires de porcherie a été développé à Singapoure. Il utilise la culture de micro-algues tant pour la réduction accélérée en lagune de la DBO5 et de la DCO de l'effluent que pour la production de protéines uni-cellulaires. On trouve une large gamme de flore algale dans les lagunes; des espèces d'-Oocystis, deMicratinium, deScenedesmus, Ankistrodesmus, deChlorella etd'Oscillatoria out été identifiées. Les comptages totaux d'algues, enregistrées de 1979 à 1981, ont donné jusqu' à 107 cellules par ml d'eau de la lagune. On a observé des variations considérables de population algale tant quantitatives que qualitatives. On ne discernait pas de spectres évidents. En conséquence, les opérations lagunaires ont été fréquemment perturbées par ces fermentations en population, qui, à leur tour, ont été attribuées à la composition hétérogène de l'effluent de porcherie, aux conditions atmosphériques et climatiques variables et à la prédation par des organismes plus conséquents, plus particulièrement desMoina. Après passage par les lagunes, les solides totaux en suspension ont été enlevés par une méthode nouvelle de flottation à l'air dissous, qui a donné un effluent limpide, présentant une réduction de DBO5 de 87%.
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7.
The IL-1 receptor antagonist (IL-1RN) is a protein that binds to IL-1 receptors and inhibits the binding of IL-1 alpha and IL-1 beta. As a consequence, the biological activity of these two cytokines is neutralized in physiological and pathophysiological immune and inflammatory responses. In this study, using a panel of somatic rodent-human cell hybrids, we show that the gene for the human interleukin-1 receptor antagonist (IL1RN) maps to the long arm of chromosome 2. Previously, we described a length variation polymorphism within the second intron of the IL-1RN gene (Steinkasserer et al., 1991, Nucleic Acids Res. 19: 5095). Segregation of this, together with an IL-1 alpha polymorphism, was followed in a panel of five CEPH families. Linkage analysis permitted the mapping of the IL-1RN gene to band q14-q21 in the region for the IL-1 alpha and IL-1 beta loci. This study supports the view that an early gene duplication event resulted in the creation of an interleukin-1 gene family.  相似文献   
8.
Steroids are extensively excreted in the bile of rats. There was no significant difference in biliary excretion of steroid following administration of [3H]-estrone sulfate into the proximal small intestine (PSI) of conventional (CVL; 17.8 +/- 62%; mean +/- SD) or germfree (GF; 28.2 +/- 5.3) rats. A similar finding resulted from administration into the distal small intestine (DSI)-CVL, 22.3 +/- 11.8%; GF, 11.4 +/- 3.7%. However, when the drug was given into the caecum, excretion in the bile of CVL rats after 5 h was 59.1% whereas in GF rats it was only 1.7%. When estrone was injected into the PSI and DSI of CVL and GF rats, absorption (as judged by excretion in bile) was more rapid than that seen with estrone sulfate. Five hours after injection into the PSI, biliary excretion was, in CVL 88.2% and in GF 81.7% and after injection into the DSI excretion was, in CVL 84.7% and in GF 83.6%. Absorption of estrone from the caeca of GF rats was apparently reduced (49.0% and 25.3% excreted in the bile of CVL and GF rats respectively). There was no significant difference in bile flow rate between CVL and GF rats. These results give unequivocal evidence of intact absorption of estrone sulfate from the small intestine of the rat. The rate of absorption is however very much reduced compared to the non-sulphated steroid. Estrone sulfate is not absorbed intact in the caecum but is hydrolysed by the gut microflora prior to absorption.  相似文献   
9.
Quantitation of serum immunoglobulin M, G, A, D and E levels was carried out in Malaysians with Brugia malayi infections. Results showed highly elevated levels of IgM and IgE as well as moderately elevated levels of IgG. These were most significant in patients with tropical pulmonary eosinophilia or elephantiasis. Serum IgE levels were extremely high in microfilaraemic patients (6,060 +/- 3,958 IU ml) probably due to a constant antigenic stimulation by dead and dying microfilariae.  相似文献   
10.
The C3b receptor of human erythrocytes is known to act as a cofactor for the cleavage of the complement protein C3b by the serine proteinase C3b/C4b Ina. The same cofactor activity is shown to be present on human tonsil B-lymphocytes. The cofactor activity of the C3b receptor can be assayed, on intact cells or in solubilized extracts of cells, by determining the rate of C3b cleavage in the presence of fixed concentrations of C3b and of C3b/C4b Ina. This assay method was used to compare the characteristics and relative quantities of C3b receptors on erythrocytes and lymphocytes. The cofactor activities associated with these two cell types resemble each other, but are distinct from the serum cofactor proteins, C4bp and Factor H, in antigenicity and in pH- and ionic-strength-dependence, and are distinct from Factor H in substrate specificity. Assay of cofactor activity in intact cells indicates that there are about 80-fold more receptors per cell on the lymphocyte surface than on erythrocytes. Assays with cells made permeable by detergent show that, whereas essentially all of the receptors on erythrocytes are on the cell surface, B-lymphocytes contain a large internal receptor pool, which makes up more than 80% of the total cofactor activity of the cell.  相似文献   
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