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71.
Akhil G. Jhingran R.C. Gupta Suprabhat Ray A.K. Agarwal M.M. Singh Nitya Anand 《Steroids》1983,42(6):627-634
The syntheses of (±) 2α,6β-diethyl-7α-ethynyl-3α-(-hydroxyphenyl)--bicyclo[4.3.0]nonan-7β-ol (), (±)2β,6β-diethyl-7α-ethynyl-3β-(-methoxyphenyl)--bicyclo[4.3.0]nonan-7β-ol () and (±) 2α,6β-diethyl-7α-ethynyl-3β-(-hydroxyphenyl)--bicyclo[4.3.0]nonan-7β-ol () and their derivatives, which are essentially B-seco-steroids having and geometries have been carried out. A study of their antiimplantation activities (AI) and receptor binding affinities (RBA) show that compounds are biologically most potent, followed by the corresponding and compounds. The most potent compound is active at 1 mg/kg in rats. Introduction of 7α-ethynyl group increases their AI activity; however, no significant effect on their RBA is observed. 相似文献
72.
From the uppermost parts of the Muth Quartzite Formation the following ammonoids are described which here are reponed from the Himalayas for the first time:Discoclymenia cucullata (v. Buch);Prionoceras (Imitoceras) intermedium Schindewolf;Pr. (I.) cf.rotundum Petter;Cyrtodymenia sp.; andDiscoclymenia striata (Münster). The levels containing ammonoids appear in the Famennian V(Clymenia zone). Their extension up to the earliest Tournaisian(Gattendorfia zone) is not likely although theoretically it cannot be excluded. 相似文献
73.
Two new compounds, isolated from the rhizomes of Cryptocoryne spiralis, have been characterized as ethyl 14-oxotetracosanoate and 15-oxoeicosanyl 14-oxoheptadecanoate by spectral data and chemical studies. Hentriacontane and sitosterol have also been isolated and identified. 相似文献
74.
75.
(Ca2+ or Mg2+)-ATPase in lung lamellar bodies 总被引:1,自引:0,他引:1
76.
Use of a New Buffer System with Formalinized Sheep Erythrocytes in the Rubella Hemagglutination-Inhibition Test 总被引:4,自引:1,他引:3 下载免费PDF全文
The increased sensitivity and improved agglutination and settling patterns of formalinized sheep erythrocytes in a new buffer, HEPES (N-2-hydroxyethylpiperazine N'-2'-ethanesulfonic acid), make this system more suitable for use in the rubella hemagglutination-inhibition test. 相似文献
77.
78.
Summary Five rates of limestone and 4 rates of fertilizers were used in a split-plot design to study their effects under field conditions
on Mo, Cu, B, Mn, and Zn levels in mixed forage tissue and soil, and on the forage yield. An increase in soil pH resulted
in an increase in Mo and Cu content of plant tissue while B, Mn, and Zn decreased. The micro-nutrient content of the tissue
increased as the harvesting season progressed. Increasing rates of applied fertilizer did not affect the micro-nutrient content
of the forage tissue or soil.
Liming to a pH of 5.6 and above reduced the availability of Mn and Zn in the soil. In general, the available B was low at
pH values greater than 6.1. Lime did not affect the quantities of Mo and Cu in the soil. Manganese is supplied in large quantities
by limestone and is not apt to be deficient in limed soil. However, addition of B and Zn may be required on the high pH soils
of Eastern Canada in future. Molybdenum was adequate where the soil was limed to a pH of 6.1 or greater.
The dry-matter yield of forage increased significantly with successive increases in lime up to pH 6.6 and with each increment
of fertilization.
Contribution No.226, Research Branch, Research Station, P.O. Box 1210, Charlottetown, P.E.I. and No.166, Experimental Farm, Nappan, N.S. 相似文献
79.
Summary Experiments were conducted to determine the influence of N, P, and K and of the NP and NK interactions on root yields and
tissue concentrations of N, P, and K of rutabagas grown on a sandy loam soil under greenhouse conditions. Root yields were
increased by applications of N and K but not by added P. The yield response to N was dependent on K supply. The highest dry
matter content in roots was associated with the lowest rates of N and K and the lowest root yields.
The N content of tissue at the early vegetative stage increased with increasing rates of N and decreased with increasing rates
of P and K. The N content of root tissue at harvest increased at the highest rates of N but was unaffected by rates of P and
K. The P and K content of root tissue increased with increasing rates of P and K, respectively.
The levels of nutrients in early vegetative tissue associated with optimum yields were about 2.6, 0.24, and 2.0% for N, P,
and K, respectively. The corresponding values in the leaf tissue at harvest were about 1.2, 0.12, and 1.5% N, P, and K, respectively.
Contribution No.222. 相似文献
80.