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31.
Abstract— Twenty-nine autopsy specimens of intracerebral tumours (nine astrocytomata, ten medulloblastomata and ten glioblastomata multiforme), as well as samples of peritumoral and apparently normal brain tissue, have been studied for Na, K, P, Ca, Mg, Cu, and S contents.
The tumour tissue, irrespective of the histological characteristics, as compared to the 'normal' and perineoplastic tissues, showed higher concentration of Ca, Mg, Cu and S. The peritumoral tissue, regardless of the tumour type, showed a higher concentration of Cu than the 'normal' control brain.
The more malignant glioblatomata and medulloblastomata. The Cu levels did not show a significant diference.  相似文献   
32.
33.
Summary Staminate flowers of the Acorn squash (Cucurbita pepo, cv. Table Queen) are initiated monosexually, pistillate flowers are initiated bisexually. Pistillate flower primordia are physiologically bisexual from a stage below 0.3 mm until they are 0.8 mm in width.Male and female floral buds were cultivated on White's medium, modified according to Galun et al. (1963). In excised female floral buds the relative development of stamens is better than in in-situ floral buds; the opposite relationship holds for ovary development. The smaller the bud at excision, the greater the stamen growth and the lesser the ovary growth, both in absolute and relative terms. Although smaller pistillate floral buds cultured in vitro showed a greater increase in maleness than larger ones, there was no difference in the percentage of female buds between explants of the two sizes when originating from the mixed stem region (that is, the stem region carrying male and female flowers). Addition of 3-indoleacetic acid and the anti-auxin p-chlorophenoxyisobutyric acid to standard medium in equal amounts resulted in somewhat better development of excised floral buds than addition of each of these compounds alone.The percentage of female buds among explants originating from identical nodes was not significantly influenced by 3-indoleacetic acid or p-chlorophenoxyisobutyric acid.Weizmann Memorial Fellow. The studies reported in this publication were mainly undertaken at the Weizmann Institute of Science  相似文献   
34.
During vitellogenesis in Musca domestica, a major hemolymph protein, in addition to vitellogenin, appears preferentially in females. This protein is synthesized by the adult fat bodies, secreted into the hemolymph, and is not taken up by the ovaries during vitellogenesis. We have designated this protein nonvitellogenic female protein (NVFP). It is composed of only one type of polypeptide (Mr=70,000) and occurs in two different forms. Synthesis of NVFP is induced by a protein diet, attaining maximum concentrations in females at the middle of the gonotrophic cycle. In males its maximum concentration never surpasses 10% of the concentration in females. The quantitative variation of the NVFP is cyclic and coincident with the gonotrophic cycles of Musca domestica.  相似文献   
35.
We have previously shown that a major granule-associated cationic protein CAP 37 (Mr = 37 kD) derived from human PMN is a monocyte-specific chemoattractant. The N-terminal amino acid sequence of this novel chemotactic protein shares significant homology with a number of inflammatory molecules with protease activity including elastase and cathepsin G. However, a critical substitution of a serine for a histidine at position 41, results in its lack of serine protease activity.  相似文献   
36.
Between November and December 1987, 201 subjects from three communities of the Cordillera Province, Santa Cruz Department, South-East Bolivia (Camiri, Boyuibe, and Gutierrez) were examined for serum iron levels. Sixty-three (31.3%) were iron deficient. There were no significant differences between males and females (37.2% and 26.9%, respectively) and among the three localities studied. Iron deficiency was highest in the 3- to 9-year-old age group and lowest in the 30- to 39-year-old group. Considering the prevalence in the same localities of infections by hookworms, Trichuris trichiura, Strongyloides stercoralis, and Trichostrongylus, it is suggested that hookworms and possibly other intestinal parasites may be an important cause of the observed iron deficiency.  相似文献   
37.
Analysis of soluble proteins from human genital skin fibroblasts by two-dimensional polyacrylamide gel electrophoresis reveals an abundant protein doublet of mol. wt 56,000 with isoelectric points (pI) of 6.7 and 6.5. This protein is absent in non-genital skin fibroblasts as well as in genital skin fibroblasts of most patients with complete forms of androgen insensitivity. The protein specifically binds androgen. A protein of similar estimated molecular weight (58,000) from human genital skin fibroblasts has recently been found to be covalently radiolabelled by the affinity ligand dihydrotestosterone 17 beta-bromoacetate (DHT-BA). In the present study these proteins have been found to be indistinguishable on one- and two-dimensional gel electrophoresis. Antibodies raised against the 56 kDa pI 6.7/6.5 protein also recognized the protein covalently radiolabelled by DHT-BA. A third protein of estimated mol. wt 59,000 has been found to be associated with several steroid hormone receptor complexes but has no known ligand binding activity. This protein was found to be clearly separable from the 56/58 kDa protein on two-dimensional gel electrophoresis as it has a more acidic pI of approximately 5.4. Furthermore, antibodies against the 59 kDa protein do not recognize the 56 kDa species, and vice versa.  相似文献   
38.
An antibody raised against a peptide in the first nucleotide-binding domain (NBD) of CFTR [1], incorporated into intact rat submandibular acini by hypotonic swelling, inhibited beta-adrenergic stimulated mucin secretion, without affecting cyclic AMP rise. The data are the first to show that a CFTR-antibody-containing cell results in defective stimulation of mucin secretion, as is seen in CF cells, and that this can be reversed by an excessive increase in cyclic AMP.  相似文献   
39.
We present complete1H NMR assignments for two synthetic glycopeptides representative of the carbohydrateprotein linkage region of serglycin proteoglycans. The peptides are: Ser(Galp-Xylp)-Gly-Ser-Gly-Ser(Galp-Xylp)-Gly and, Ser(Galp-Xylp)-Gly-Ser(Galp-Xylp)-Gly-Ser(Galp-Xylp)-Gly. A number of 2D NMR spectra together with a 3D NOESY-TOCSY spectrum were acquired at 600 MHz to complete the assignments of the glycopeptides dissolved in water with 40% trifluoroethanol. Preliminary analysis of the NMR data suggests folded structures for the glycopeptides.A preliminary account of this work was presented at an International Symposium held at the University of Alabama at Birmingham in November, 1994 on the occasion of the 65th birthday of Professor Lennart Rodén.  相似文献   
40.
Summary Fe (III) and Cu (II) each at 50 M in four commercial strains of Saccharomyces cerevisiae induced an increase of NAD(P)+ reduction in one strain (Turkish), but two others (Chilean and Brazilian), the presence of Fe(III) and/or Cu(II) diminished NAD(P)+ reduction presumably due to free radicais formation inside these living cells. Suprisingly, in the American strain, Fe(III) induced a decrease and Cu (II) an increase of NAD(P)+ reduction.  相似文献   
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