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61.
Michael J. Renner Allyson J. Bennett Michele L. Ford Peter J. Pierre 《Primates; journal of primatology》1992,33(3):315-327
Investigatory behavior with novel, inanimate objects by two groups of four juvenile greater bushbabies (Otolemur garnettii) was examined in the laboratory. Substantial investigatory behavior was shown by all subjects. In the first study, subjects
showed interest in a wide variety of nonfood stimulus objects. In the second, subjects displayed sustained interest in and
investigation of non-food stimulus objects over three sessions. Bushbabies showed preferences for larger, more manipulable
objects and variations in total contact over days. Individual differences were observed in the duration and types of contact
with objects. These observations contradict earlier reports that prosimians show little interest in inanimate, non-food objects. 相似文献
62.
63.
A microtechnique has been developed for the measurement of alkaline phosphatase in minute amounts of renal tissue. This microtechnique utilizes the known fluorescent property of 4-methylumbelliferyl phosphate following enzymatic hydrolysis. The reaction is sensitive and reproducible and is inhibited by l-bromotetramisole, a specific alkaline phosphatase inhibitor. The microdetermination of alkaline phosphatase activity in the various segments of the mouse nephron allowed the localization of the enzyme in the glomeruli, and in the proximal convoluted tubule where the activity progressively decreases from the capsule of Bowman to the more distal segments. The enzyme was absent from the pars recta or S3 and from the rest of the nephron. This technique is applicable to very small amounts (0.1 μg of protein) of any tissue containing alkaline phosphatase. 相似文献
64.
Gilbert C. Pogany Michele Corzett Sue Weston Rod Balhorn 《Experimental cell research》1981,136(1):127-136
A variety of biochemical and histochemical techniques have been used to compare the composition of chromatin in sperm nuclei isolated from the epididymides of five mouse strains. The DNA content was determined by phosphorus analysis, deoxyribose analysis, absorption spectroscopy at 260 nm, and cytomorphometry following gallocyanine chrome alum staining. All four methods indicate that the mouse sperm nucleus contains approx. 3.3 pg DNA and that the DNA content does not vary significantly among the strains tested. Three different techniques, quantitative amino acid analysis, absorption spectroscopy at 230 nm, and sperm head density analysis in cesium chloride, were used to determine the protein content. Sperm nuclei from each strain of mouse were found to have a protein to DNA ratio of 0.9 and a chromatin protein content of 3 pg/nucleus. Comparisons of the basic proteins by disc gel electrophoresis demonstrate that the sperm nuclei contain only protamine and lack significant levels of somatic histones or transition proteins. The sperm from each strain contained both mouse protamine variants and the relative distribution of the two proteins did not appear to differ among strains. Using this information, we have been able to draw certain conclusions regarding DNA-protamine interactions and the mode of DNA packaging in the sperm nucleus. The most important of these is that the DNA in the mouse sperm nucleus cannot be packaged in nucleosomes. The protamines in sperm chromatin do not function as structural proteins, providing a subunit core around which the DNA is wrapped, but appear to completely neutralize the phosphodiester backbone of the DNA molecule, thereby minimizing the repulsion between neighboring segments of DNA and allowing it to be condensed into a biochemically inactive particle of genetic information. 相似文献
65.
Marco Gobbi Michele Baccarani Donatella Ruggero Sante Tura the Italian Cooperative Study Group on Chronic Myeloid Leukemia 《Cancer immunology, immunotherapy : CII》1979,6(1):59-62
Summary Serum immunoglobulin concentration and skin reactivity to at least three recall antigens were determined in 210 patients with chronic myeloid leukemia (CML). Immunoglobulin concentration was normal in the great majority of the patients. Skin tests were negative in 50 of 210 cases (24%). No relationship could be demonstrated between skin reactivity, age, time since diagnosis, WBC, lymphocyte count, and splenectomy. Prior antileukemic therapy was a major factor in determining the response to skin tests.S. Tura (Chairman) and M. Baccarani (Secretary), Cattedra di Ematologia dell'Università e Servizio di Ematologia dell'Ospedale S. Orsola, Bologna; G. de Sandre, G. Perona, G. Cetto, G. Pizzolo, Istituto di Patologia Medica e Cattedra di Ematologia dell'Università, Verona; P. Rambotti, B. Falini, Clinica Medica dell'Università, Perugia; T. Chisesi, G. Capnist, Divisione di Ematologia, Ospedale Civile, Vicenza; A. Cajozzo, P. Citarella, Cattedra di Ematologia dell'Università, Palermo; G. Broccia, Sezione di Ematologia, Ospedale Armando Businco, Cagliari; V. Liso, G. Troccoli, Clinica Medica II dell'Università, Bari; L. Bruzzese, G. Nappi, A. Abbadessa, Clinica Medica (I Facoltà) dell'Università, Napoli; A. Porcellini, C. Delfini, Divisione di Ematologia, Ospedali Riuniti, Pesaro; E. Cacciola, R. Giustolisi, R. Musso, V. Raimondi, Cattedra di Ematologia dell'Università, Catania; G. Torlontano, L. Geraci, Cattedra di Ematologia dell'Università, Chieti, e Divisione di Ematologia, Ospedale Civile, Pescara; F. Mandelli, G. Mariani, B. Monarca, N. Petti, Cattedra di Ematologia dell'Università, Roma; R. di Guglielmo, A. Miliani, Clinica Medica dell'Università, Firenze; C. Bernasconi, M. Lazzarino, G. Castelli, Divisione di Ematologia, Ospedale S. Matteo, Pavia; A. Alberti, S. Magro, Servizio di Ematologia, Ospedale Generale Regionale, Catanzaro; A. Neri, P. Iacopino, Divisione di Ematologia, Ospedali Riuniti, Reggio Calabria; R. Delsignore, M. C. Baroni, Istituto di Patologia Medica dell'Universita, Parma; E. Bajetta, S. Monfardini, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milano; S. Tognella, Istituto Scientifico di Medicina Interna, Cattedra di Clinica Medica 2R, Università, Genova. 相似文献
66.
A new method for the determination of inorganic phosphorus (Pi) in 4 nl of renal tubular fluid is described. Phosphate is converted to hexadimolybdatophosphate, which is reacted with thiamine to produce a highly fluorescent thiochrome. The reaction is stable and reproducible. Problems of interference are minimal. Microdeterminations of Pi in the proximal tubules and glomerular filtrates of the rat yielded results similar to those published in the literature. 相似文献
67.
Isolation and Characterization of Sex-Linked Female-Sterile Mutants in DROSOPHILA MELANOGASTER 总被引:15,自引:14,他引:1
The purpose of the experiments described was to identify X chromosome genes functioning mainly or exclusively during oogenesis. Two mutagenesis experiments were carried out with ethyl methane sulfonate. Following treatment inducing 60% lethals, 9% of the treated X chromosomes carried a female sterility mutation which did not otherwise seriously affect viability. Among —95 isolated mutants, 19 were heat-sensitive and 5 cold-sensitive. The mutants have been classified as follows: I (16 mutants; 12 complementation groups): the females laid few or no eggs; the defect concerned either ovulation or oogenesis. II (37 mutants; 18 complementation groups): the female laid morphologically abnormal eggs, often with increased membrane permeability. III A (13 mutants; at least 8 complementation groups): the homozygous females were sterile if mated to mutant males; their progeny (homo- and hemizygous) died at a late embryonic stage (11 mutants), at the larval stage (1 mutant) or at the pupal stage (1 mutant). However fertility was partly restored by breeding to wild-type males as shown by survival of some heterozygous descendants. III B (29 mutants; 22 complementation groups): the fertility of the females was not restored by breeding to a wild-type male. Most of the eggs of 13 of the mutants died at a late stage of embryogenesis. The eggs of the others ceased development earlier or, perhaps, remained unfertilized. The distribution of the number of mutants per complementation group led to an estimation of a total of about 150 X-linked genes involved in female fertility. The females of three mutants, heat-sensitive and totally sterile at 29°, produced at a lower temperature descendants morphologically abnormal or deprived of germ cells. Three other mutants not described in detail showed a reduction in female fertility with many descendants lacking germ cells. A desirable mutant which was not recovered was one with normal fertile females producing descendants which, regardless of their genotype, bore specific morphological abnormalities. The value of the mutants isolated for analysis of the complex processes leading to egg formation and initiation of development is discussed. 相似文献
68.
Claudio Gualerzi Michele Grandolfo Hasko H. Paradies Cynthia Pon 《Journal of molecular biology》1975,95(4):569-573
The circular dichroism spectra of Escherichia coli 30 S ribosomal subunits have been determined between 200 and 320 nm in the presence and in the absence of initiation factor IF-3. The addition of IF-3 did not produce any major alteration of the circular dichroism spectrum of the 30 S subunits between 320 and 240 nm, but resulted in an increase of the negative ellipticity between 240 and 205 nm. The effect was maximal for an IF-3:30 S molar ratio of approximately one, and further addition of IF-3 did not lead to a further increase of ellipticity. A similar effect was not seen when the 30 S ribosomal subunits were previously heat-inactivated to destroy their IF-3 binding capacity. These data indicate that the ribosomal binding of IF-3 may be accompanied by an increase in the secondary structure of the ribosomal proteins, but does not involve any major net change in the secondary structure of the rRNA. 相似文献
69.
Pellegrino Michele A. Curry Russell A. Pellegrino Anna G. Hoch James A. 《Immunogenetics》1975,2(1):543-549
Immunogenetics - The established human lymphoid cell lines 6410 and WI-L2 exhibit the recently discovered receptor for monkey red blood cells (MRBC). This receptor is specific for B cells. These... 相似文献
70.
Federico Riu Roberta Ibba Stefano Zoroddu Simona Sestito Michele Lai Sandra Piras Luca Sanna Valentina Bordoni Luigi Bagella Antonio Carta 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):2223
Introduction: Colchicine-binding site inhibitors are some of the most interesting ligands belonging to the wider family of microtubule-destabilising agents.Results: A novel series of 4′-fluoro-substituted ligands (5–13) was synthesised. The antiproliferative activity assays resulted in nM values for the new benzotriazole-acrylonitrile derivatives. Compound 5, the hit compound, showed an evident blockade of HeLa cell cycle in the G2-M phase, but also a pro-apoptotic potential, and an increase of early and late apoptotic cells in HeLa and MCF-7 cell cycle analysis. Confocal microscopy analysis showed a segmented shape and a collapse of the cytoskeleton, as well as a consistent cell shrinkage after administration of 5 at 100 nM. Derivative 5 was also proved to compete with colchicine at colchicine-binding site, lowering its activity against tubulin polymerisation. In addition, co-administration of 5 and doxorubicin in drug-resistant A375 melanoma cell line highlighted a synergic potential in terms of inhibition of cell viability.Discussion: The 4′-fluoro substitution of benzotriazole-acrylonitrile scaffold brought us a step forward in the optimisation process to obtain compound 5 as promising MDA antiproliferative agent at nanomolar concentration. 相似文献