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1.
S K Tandon A K Mathur J R Behari S V Chandra 《Acta biologica et medica Germanica》1975,34(11-12):1835-1842
Daily intraperitoneal administration of thorium nitrate produced progressive morphological and biochemical alterations with the increase in thorium concentration in rat testis. The degenerative changes in the seminiferous tubules increased with the duration of treatment and after 90 days calcification occurred in about 25% of the tubules and in the connective tissue of the tunica albuginea. The activity of adenosine triphosphatase and alkaline phosphatase increased markedly as a result of thorium administration. An attempt has been made to interrelate histopathological and enzymatic changes and the metal concentration in the testicular tissue. 相似文献
2.
G K Pande V M Reddy P Kar P Sahni M Berry B N Tandon S Nundy 《BMJ (Clinical research ed.)》1987,295(6606):1115-1117
Between 1976 and 1984, 136 patients with portal hypertension due to extrahepatic obstruction were operated on. Twenty two patients had emergency and 114 elective operations. The operative mortality was 9% and 1%, respectively. Altogether 117 patients (86%) were followed up for from two to 10 years: 17 rebled, none developed encephalopathy or sepsis after splenectomy, and 90% and 75% were alive at five and 10 years respectively. Unlike endoscopic sclerotherapy and treatment with propranolol, operative treatment of variceal bleeding can usually be completed during one admission and carries a low mortality and a fairly low morbidity. Operation seems to be the best form of treatment for poor patients living far from medical facilities in developing countries and may be the treatment of choice in developed countries as well. 相似文献
3.
Ascorbic acid levels were found to be closely related to different stages of growth and maturity of Avitellina centripunctata, Moniezia expansa, and Stilesia globipunctata from goats and sheep and of Raillietina echinobothrida from fowl. The ascorbic acid level in avian parasites was higher than that in mammalian. The level was highest in immature proglottides and lowest in gravid proglottides. 相似文献
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5.
Liquid membrane bilayers, generated by bacteriorhodopsin on a supporting membrane, exhibit photo osmosis. The phenomenon has been shown to be a consequence of light-induced electrical potential differences which develop across the liquid membrane bilayer due to the light-driven proton pumping action of bacteriorhodopsin. The variations of photo osmotic velocity with wavelength, intensity of light, and proton acceptor concentrations has been studied. 相似文献
6.
A Tandon C Das B L Jailkhani A Gaur S Sehgal G Gopinath G P Talwar 《Journal of reproduction and fertility》1984,70(2):369-377
Mice given daily i.p. injections of immunoglobulins against ovine LH on Days 3-7 of pregnancy were devoid of implantation sites on Day 8 whereas mice treated with antibodies to hCG had embryos of normal number and appearance on Day 8. These antibody treatments reduced the mean +/- s.d. serum progesterone concentrations from 65.4 +/- 15.3 ng/ml (control globulins) to 8.6 +/- 4.9 ng/ml (anti-LH) and 9.2 +/- 3.1 ng/ml (anti-hCG) on Day 8 and had no differential effect on serum oestrogen levels on Day 4. However, the mice treated with anti-hCG did not litter; resorption of the embryos took place between Days 10 and 14 of pregnancy. Indirect immunofluorescence and quantitative immunoenzymic assays showed the presence of anti-ovine LH and anti-hCG reacting antigens in the mouse feto-placental unit. On Day 6, the values of reacting antigens (mean +/- s.d. absorbance units/10 micron section of embryo) were 0.050 +/- 0.002 with control globulins, 0.059 +/- 0.002 with anti-hCG-Ig and 0.196 +/- 0.018 with anti-LH-Ig; the corresponding values on Day 12 were 0.075 +/- 0.009, 0.402 +/- 0.02 and 0.416 +/- 0.015. The quantitative disposition of the reacting antigens to the two types of anti-gonadotrophins seems to bear a temporal relationship to their respective antifertility action. The pregnancy terminating action of immunoglobulins to ovine LH (Days 6, 7 & 8) and hCG (Days 8, 9 & 10) was counteracted by administration of 2 mg medroxyprogesterone acetate on Days 6, 9 and 12, indicating the importance of progesterone in the maintenance of pregnancy in the mouse. 相似文献
7.
Levonorgestrel which binds with high affinity to SHBG, is suggested as a new radioligand for estimation of SHBG in human plasma. Using 3H-levonorgestrel as a ligand, a number of samples from men, women pregnant and non-pregnant were analysed. The SHBG content was lowest in men, low in women and rose to higher level during pregnancy. The results of the present study suggest that levonorgestrel appears to be a better ligand than dihydrotestosterone for measuring SHBG. 相似文献
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9.
Francesco Ricci Kshitij Tandon Maria Moßhammer Ellie H.-J. Cho Linda L. Blackall Michael Kühl Heroen Verbruggen 《Environmental microbiology》2023,25(8):1505-1521
The coral skeleton harbours a diverse community of bacteria and microeukaryotes exposed to light, O2 and pH gradients, but how such physicochemical gradients affect the coral skeleton microbiome remains unclear. In this study, we employed chemical imaging of O2 and pH, hyperspectral reflectance imaging and spatially resolved taxonomic and inferred functional microbiome characterization to explore links between the skeleton microenvironment and microbiome in the reef-building corals Porites lutea and Paragoniastrea benhami. The physicochemical environment was more stable in the deep skeleton, and the diversity and evenness of the bacterial community increased with skeletal depth, suggesting that the microbiome was stratified along the physicochemical gradients. The bulk of the coral skeleton was in a low O2 habitat, whereas pH varied from pH 6–9 with depth. Physicochemical gradients of O2 and pH of the coral skeleton explained the β-diversity of the bacterial communities, and skeletal layers that showed O2 peaks had a higher relative abundance of endolithic algae, reflecting a link between the abiotic environment and the microbiome composition. Our study links the physicochemical, microbial and functional landscapes of the coral skeleton and provides new insights into the involvement of skeletal microbes in the coral holobiont metabolism. 相似文献
10.
Low concentrations of wheat germ agglutinin (4 micrograms/ml) have been shown to act synergistically to induce platelet aggregation with epinephrine, collagen, arachidonate and ionophore A23187. Aggregation ceased on the addition of the haptenic sugar N-acetylglucosamine at any time following the onset of aggregation with these agonists and a small degree of disaggregation was observed during the reversible first wave with the biphasic aggregating agents epinephrine and ADP. Cyclooxygenase inhibitors such as indomethacin and aspirin blocked the second wave of aggregation with the biphasic aggregating agents epinephrine and ADP but a synergistic response continued to be shown with the first wave in the presence of these inhibitors. Release of [14C]serotonin and the mobilization of [3H]arachidonate by epinephrine and collagen were markedly stimulated in the presence of wheat germ agglutinin but there was no increase of either radiolabel in the case of ADP. Platelet shape change, but not aggregation, occurred with low levels of wheat germ agglutinin and the synergistic response with ADP, collagen or ionophore A23187 occurred without further shape change. Wheat germ agglutinin did not affect the basal or stimulated levels of cyclic AMP. The membrane fluidity of platelets was not affected by the lectin or by thrombin as shown by the lack of change in fluorescence polarization with diphenylhexatriene. It is suggested that the binding of wheat germ agglutinin to the platelet surface induces platelet activation by mechanisms similar to those of other agonists and that it may affect the distribution of membrane-bound Ca2+ by a reversible perturbation of the platelet membrane. 相似文献