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Non-histone chromatin proteins synthesized during chicken embryonic liver development were labeled with [3H]tryptophan and [3H]methionine and characterized by electrophoresis. During embryonic development protein/DNA ratio in chromatin was low (1.30-1.62) but synthesis of non-histone protein was high. Especially one characteristic fraction K (MW 18 000), tightly bound with DNA was preferentially associated with DNAase II sensitive, active transcribed sequences. In 7-day old and adult chicken synthesis of all non-histone proteins was low, fraction K was absent or synthesized only in small amounts in association with non-active sequences, however protein/DNA ratio in chromatin was high (2.30-2.33).  相似文献   
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A viable wheat hybrid intermediate of the same height as the parents was obtained by crossing the female parent of tall variety NP4 with the male parent of the dwarf variety HD2160. Seeds of the hybrid and its parents were germinated and their growth pattern as well as the activities of peroxidase, indolyl-3-acetic acid oxidase and amylase in extracts made from them were studied at the early seedling stages i.e. up to 96 h.
A positive correlation existed between the length of the axis at the early seedling stage and at mature plant height as far as the parental varieties are concerned but no such correlation was observed with the hybrid. Growth of the hybrid seedlings was less than of its parents. Light appeared to stimulate the longitudinal growth of the axis to different extents in the parents and hybrid. Higher activities of peroxidase, indolyl-3-acetic acid oxidase and amylase were observed in the hybrid as compared to both of its parents. Lethal wheat hybrid also exhibits increased activities of amylase, indolyl-3-acetic acid oxidase and peroxidase. Therefore, it appears that seedling growth and enzyme activities at the seedling stage are not always correlated with hybrid vigour.  相似文献   
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The traditional cranioscopic traits possess undoubted taxonomic value in interpreting interpopulational relationships. However, there is a lack of studies on the correlations between particular traits. In order to fill this gap, the following set of 4 traits was analysed by use of the multiple stachastic correlations method of Wanke: 1. prominence of maxilla, 2. lower margin of nasal aperture, 3. depth of canine fossa and 4. depth of maxillary incisure. These traits were examined by use of the photographic scales of Michalski within the series of 104 crania from a local population of Wislica, Poland, dated to the Early Medieval Period. The significant associations appeared in the combinations 1–2, 1–3, 3–4, 1–2–3, 1–2–4, 1–3–4, 2–3–4 and 1–2–3–4. After removal of all the possible interactions, still significant associations remained in 1–2–4, 2–3–4, and 1–3–4. Moreover, the places of significant surpluses appeared in the extreme places, i.e. those characterising the Europoid and Mongoloid crania.  相似文献   
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The levels of serum fatty acids in the serum and in the serum fractions of cholesterol esters (ECH) and triglycerides (TG) and the levels of these acids in these fractions of platelets were compared in healthy controls and in patients with clinically manifested coronary arterial disease. Decreased level of linoleic acid was found in the serum and in the ECH fraction of the serum in the patients, with a rise in the level of palmitic acid in the ECH fraction of the serum of these patients. The level of linoleic acid in the ECH and TG platelet fractions in these patients was not different from that in the healthy controls, while in the platelet TG fraction of the patients the level of palmitoleic acid was raised, and the level of oleic acid was increased in the platelet ECH fraction.  相似文献   
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