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61.
Callus cultures of 18 sugarbeet (Beta vulgaris) lines, two accessions of B. maritima and a B. macrocarpa accession were initiated from aseptically germinated seeds. Plant regeneration through organogenesis was obtained either on MS or B5 medium containing various concentrations and combinations of naphthaleneacetic acid (NAA), 6-benzylaminopurine (BAP), 2,3,5-triiodobenzoic acid (TIBA) and abscisic acid (ABA). Genotypes differed in their abilities of callus formation and regeneration: seven out of 18 sugarbeet lines, and an accession of B. maritima were capable of regenerating plantlets. Our data also indicated that 2 M TIBA promoted morphogenesis from callus culture in the presence of 5 M BAP.  相似文献   
62.
A water-soluble protein (called "33-kDa protein") that exhibits light-dependent phosphorylation has been shown to be a major protein of mammalian rod photoreceptors. Although the function of this protein is unknown, it has been implicated in the biochemical cascade mediating the rod visual response. Using a retinal cDNA from the rat and somatic cell hybrids, we have mapped the gene corresponding to this protein to mouse Chromosome 1 and, by analyzing the progeny of an intersubspecific backcross, have positioned it near Lamb2 (the beta 2 chain of laminin). We have designated the gene Rpr-1 (rod photoreceptor protein-1).  相似文献   
63.
Evidence for the existence of cytoskeleton-bound polysomes in plants.   总被引:2,自引:0,他引:2  
When conventional, high ionic strength buffers were used for the isolation of polysomes from pea plants, less than 20% were retained in the detergent-insoluble pellet. Reducing Tris, K+ and Mg++ to 10 mM increased retention to 70%, and when a new, microfilament-stabilizing buffer was used, retention increased to 80%. Conditions which favoured polysome pelleting at lower g forces permitted the retention of actin in the pellet. The data are consistent with the hypothesis that higher plants, like animals, contain cytoskeleton-(actin)-bound polysomes.  相似文献   
64.
Antiserum was raised against 3-O-MeGal beta 1----3GalNAc alpha 1----3[6' -O-(2-aminoethylphosphonyl)Gal alpha 1----2 (2-aminoethylphosphonyl----6)Gal beta 1----4Glc beta 1----1Ceramide (SGL-II) isolated from the skin of a mollusc, Aplysia kurodai. This antiserum reacted with SGL-II and other phosphonoglycosphingolipids of Aplysia such as SGL-I', F-21, and some minor glycolipids on TLC plates, but it did not react with ganglioside or globoside. The sugars recognized were 3-O-methylgalactose at the non-reducing end and galactose at the branched chain of the glycolipids. One membrane glycoprotein (Mr 280,000) reacted strongly, and some other proteins reacted weakly with the antiserum. Immunohistochemical examination of the nervous tissues revealed distinct staining in the periganglionic tissue of the ganglia, and the perineural sheath of the proximal portion of the peripheral nerves. The neuropil and satellite cells were also stained. In the skin, subcutaneous connective tissues were moderately stained, and the cytoplasm of small mononuclear cells and foamy cells was also stained. The staining patterns were essentially the same in paraffin and cryostat sections. From the findings with sections pretreated with chloroform-methanol (2 : 1, v/v), it was suggested that the periganglionic and perineural stainings were due to glycoproteins, including an SDS-soluble glycoprotein of Mr 280,000, while those of the other regions were due to SGL-II and glycolipids immunologically related to SGL-II. The stainings in the skin sections were largely due to glycoproteins.  相似文献   
65.
The F2 progeny of a cross between a chromosome 2 multiple marker stock and an adapted cultivar of barley were analyzed for four morphological markers and electrophoretic patterns of eight leaf isozymes. TheIdh-2 locus was linked to thePer-5 locus (27.96±5.07 cM) and to thee locus (10.26±3.13 cM). Also, thePer-5 ande loci were located on the short arm of chromosome 2. In additionIdh-2 was also located on barley chromosome 2 and was linked to thev locus (13.18±3.56 cM), which is located on the long arm of chromosome 2. Two other marker genes,li andwst,,B, were linked (26.50±5.24 cM) on chromosome 2 but segregate independently of the other loci evaluated. This project was supported by funds from the U.S.-Spain Joint Committee for Scientific and Technological Cooperation.  相似文献   
66.
67.
Glucoamylase and alpha-amylase have been purified from a crude enzyme preparation of Aspergillus sp. K-27. The former was thermostable and seemed to have a "starch-binding site", judging from the results of a kinetic study, and the latter synergistically enhanced the degradation of starch granules with glucoamylase.  相似文献   
68.
We report a 31-year-old female with Graves' disease associated with an autonomously functioning thyroid nodule (AFTN) (Marine-Lenhalt syndrome) in which the AFTN spontaneously became a cold nodule. Initially the patient was thyrotoxic and had diffuse goiter with an elevated radioiodine uptake. She became euthyroid following six months of antithyroid drug therapy, and in addition to diffuse goiter, the solitary hot nodule was palpable in the left lobe. Fourteen months later, hyperthyroidism recurred and the thyroid scan revealed diffuse radioiodine uptake with a cold area in the nodular region. The resected nodule showed extensive degeneration and the histological diagnosis was follicular adenoma with Graves' disease. We discussed the significance of recognizing the syndrome and also compared the frequency of spontaneous degeneration in AFTN and in solitary cold nodules.  相似文献   
69.
Maternal adrenocortical function was studied by measuring plasma cortisol and urinary free cortisol during gestation. Changes in suppressibility of pituitary-adrenocortical function were determined by dexamethasone administration. Urinary free cortisol as well as plasma cortisol increased during the course of gestation. The suppressibility by dexamethasone became less effective as pregnancy advanced. These results suggest that pregnant women have pituitary-adrenocortical hyperfunction and tissue refractoriness to glucocorticoid which increases during the course of gestation.  相似文献   
70.
Human corticotropin-releasing hormone (hCRH) test was performed in 57 normal volunteers and 102 patients with hypothalamic, pituitary and adrenocortical diseases. Intravenous bolus injection of synthetic hCRH, 100 micrograms for adults or 1.5 micrograms/kg for children, increased plasma ACTH and cortisol levels in about 90% of normal subjects. In 47 patients with Cushing's disease, plasma ACTH tended to show an exaggerated response to hCRH and peak ACTH was the most frequent abnormal component among the several reaction parameters. Poor responders among normal subjects and patients with Cushing's disease had significantly higher plasma cortisol levels before CRH administration. Patients with hypothalamic hypopituitarism showed exaggerated response, whereas patients with primary pituitary lesion, isolated ACTH deficiency or adrenal Cushing's syndrome showed no ACTH response. These differences in the response of patients suggest the value of the hCRH test in their differential diagnosis.  相似文献   
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