abstract：:The appearance of RNP droplets associated with specific regions of polytene chromosomes from Chironomus larvae has been studied, systematically by light microscopy using glutarladehyde fixation and lactic acid squashing of the salivary gland. During the fourth larval instar the highest frequency of nuclei which contai...

journal_title：Chromosoma

authors： Stockert JC,Díez JL

更新日期：1979-09-01 00:00:00

abstract：:Spermatogenesis in the F1 hybrid (2n=24=12 female + 12 male) between the closely related newt species T. cristatus carnifex and T. marmoratus was apparently normal up to pachytene. Many unpaired chromosomes were present at diplotene and a typical diakinesis was lacking. Primary spermatocytes at meta- and meta-anaphase...

journal_title：Chromosoma

authors： Mancino G,Ragghianti M,Bucci-Innocenti S

更新日期：1979-08-10 00:00:00

abstract：:Chromosomes were subjected to either prolonged hypotonic solution pretreatment or aging. Both conditions greatly loosened and dispersed the overlying epichromatin from the central chromosome core structure. This was followed by silver staining and examination with bright-field microscopy. The chromosome core selective...

journal_title：Chromosoma

authors： Howell WM,Hsu TC

更新日期：1979-06-21 00:00:00

abstract：:Metaphase chromosomes from the Chinese hamster cell line M3-1 were separated by means of a flow sorter. Two chromosome fractions were used for this study: A, which consisted of 95% pure chromosome no. 1, and B, which was 90% pure chromosome no. 2. The DNA of 10(6) chromosomes of each type was purified, and a 125I-cRNA...

journal_title：Chromosoma

authors： Sawin VL,Rowley JD,Carrano AV

更新日期：1979-01-31 00:00:00

abstract：:The 5S RNA gene content of polyploid cells of the ovary of Drosophila melanogaster has been compared in animals with two or three gene clusters. The amount of 5S RNA genes is exactly proportional to the number of gene clusters as determined by DNA-RNA filter hybridization. In contrast, the number of rDNA genes in endo...

journal_title：Chromosoma

authors： Renkawitz-Pohl R

更新日期：1979-01-31 00:00:00

abstract：:Rates of movement of univalents at prometaphase and of half-bivalents at anaphase in living cricket and grasshopper spermatocytes were determined as a function of the distance from the pole toward which the movement was directed. In the artificially produced univalents of cricket cells, correlation coefficients for ra...

journal_title：Chromosoma

authors： Wise D

更新日期：1978-11-22 00:00:00

abstract：:The mean DNA content of G2 macronuclei varies during the life cycle of the ciliate Tetrahymena thermophila. Early in the life cycle the mean is about 130 C; later it is about 94 C. In hybrids between strains A and B the decrease from 130 C to 94 C usually began after 60 fissions after conjugation. In B X B clones the ...

journal_title：Chromosoma

authors： Doerder FP,DeBault LE

更新日期：1978-10-20 00:00:00

abstract：:By using the optical properties of birefringence of DNA, the arrangement of these molecules has been studied in Dinoflagellate chromosomes and Dipteran polytene chromosomes. These latter are used, here, as a reference material. These observations have been made under a polarizing microscope on intact and stretched chr...

journal_title：Chromosoma

authors： Livolant F

更新日期：1978-08-21 00:00:00

abstract：:The time sequence of DNA replication in partially synchronized human amniotic fluid cells has been analysed, employing BrdU incorporation techniques.--Regardless of the interval between removal of the methotrexate/uridine block and addition of BrdU during S-phase, the treatment results in an R-type replication pattern...

journal_title：Chromosoma

authors： Schempp W,Vogel W

更新日期：1978-06-28 00:00:00

abstract：:A new method is described which allows the purification of large quantities of nuclei (germinal vesicles) from Xenopus laevis vitellogenic oocytes of different developmental stages. From the isolated nuclei, purified nucleoli were obtained. The isolated germinal vesicles are transcriptionally active showing endogenous...

journal_title：Chromosoma

authors： Scalenghe F,Buscaglia M,Steinheil C,Crippa M

更新日期：1978-05-16 00:00:00

abstract：:Metaphase chromosomes prepared from colcemid-treated mouse L929 cells by non-ionic detergent lysis exhibit distinct heterochromatic centromere regions and associated kinetochores when viewed by whole mount electron microscopy. Deoxyribonuclease I treatment of these chromosomes results in the preferential digestion of ...

journal_title：Chromosoma

authors： Rattner JB,Krystal G,Hamkalo BA

更新日期：1978-04-25 00:00:00

abstract：:Using indirect immunofluorescence visualization techniques we investigated the distribution of RNA polymerase B (or II) and histone H1 at heat shock puff loci in Drosophila melanogaster polytene chromosomes at different times during and after heat shock. After heat treatments of from 5 to 45 min, the heat shock puff d...

journal_title：Chromosoma

authors： Greenleaf AL,Plagens U,Jamrich M,Bautz EK

更新日期：1978-01-16 00:00:00

abstract：:When A-banded human chromosomes mounted in water are transferred to an organic mounting medium, the chromosomes show uniform bright quinacrine fluorescence. This change is reversible. It is inferred that quinacrine is bound uniformly along the chromosomes, and that Q-banding is a consequence of a non-uniform distribut...

journal_title：Chromosoma

authors： Sumner AT

更新日期：1977-12-06 00:00:00

abstract：:Human satellite DNAs I, II and IV were transcribed to yield radioactive complementary RNAs (cRNAs). These cRNAs were hybridised to metaphase chromosomes of man, chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla) and orang utan (Pongo pygmaeus). The results of this in situ hybridisation were analysed quantitativel...

journal_title：Chromosoma

authors： Gosden JR,Mitchell AR,Seuanez HN,Gosden CM

更新日期：1977-09-27 00:00:00

abstract：:Chromosome fibers isolated from lymphocyte nuclei and prepared for electron microscopy by techniques designed to preserve their native structure have a distinctly knobby appearance, suggesting that DNA and protein are not distributed evenly along the fiber axis. Individual knobs (superbeads) are arranged in tandem and...

journal_title：Chromosoma

authors： Hozier J,Renz M,Nehls P

更新日期：1977-07-18 00:00:00

abstract：:Spermatogenic cells of the mouse have been separated by gravity sedimentation using a modification of a previously published method. Details are given for the collection of purified samples of specific meiotic stages and for the collection of labelled cell fractions following injection of 3H-thymidine. Suppression of ...

journal_title：Chromosoma

authors： Chandley AC,Hotta Y,Stern H

更新日期：1977-07-08 00:00:00

abstract：:The large heterochromatic chromosome of Drosophila nasutoides reveals distinctive C- and Q-bands. The regions which are negative in C-banding appear positive in Q-banding. The isochromosomic nature of this chromosome and the locality of the satellite DNAs in this chromosome are discussed with respect to these banding ...

journal_title：Chromosoma

authors： Lee CS,Collins L

更新日期：1977-04-27 00:00:00

abstract：:Antitubulin antibody was used as an immunofluorescent and immunoelectron microscopic probe to localize tubulin in components of the mitotic apparatus of rat kangaroo (strain PtK1) cells in vitro. In addition to the detection of tubulin in the spindle microtubules and centrioles, other structures were found to display ...

journal_title：Chromosoma

authors： Pepper DA,Brinkley BR

更新日期：1977-04-19 00:00:00

abstract：:Experiments were designed to test whether nonrandom segregation of sister chromatids at mitosis has a role in the production of cell diversity during embryogenesis, Segregation was examined in vivo in retinal cells from embryonic chicks. Chromatids were labelled with bromouracil and stained by the fluorescence plus Gi...

journal_title：Chromosoma

authors： Morris VB

更新日期：1977-03-16 00:00:00

abstract：:Triplet conjugation occurs frequently when three different mating types of T. thermophila are mixed under appropriate conditions. Genetic studies show that fertilization is usually tripolar, with each conjugant contributing a pronucleus to one mate and receiving a pronucleus from the other. Triplets are less common an...

journal_title：Chromosoma

authors： Preparata RM,Nanney DL

更新日期：1977-03-07 00:00:00

abstract：:By taking advantage of the fact that fluorescent light (FL) induces strand breaks only in bromodeoxyuridine(BrdUy-substituted DNA, and that those breaks eventually lead to the formation of sister chromatid exchanges (SCEs), the response of SCEs to FL was studied carefully in Chinese hamster chromosomes in which, out o...

journal_title：Chromosoma

authors： Kato H

更新日期：1977-02-03 00:00:00

abstract：:Membrane-free folded chromosomes were purified from log-phase cultures of Escherichia coli and prepared for electron microscopy by aqueous (Kleinschmidt and Zahn) spreading. The appearance of the chromosomes depended on the salt concentrations in spreading. At certain salt concentration, the chromosomes resembled rose...

journal_title：Chromosoma

authors： Kavenoff R,Bowen BC

更新日期：1976-12-16 00:00:00

abstract：:DNA reassociation kinetics were studied, by means of the hydroxyapatite chromatography method, for four species of Amphibians with different nuclear DNA content: Xenopus laevis (3 pg DNA per haploid genome) and Bufo bufo (7 pg) of the Anura subclass and Triturus cristatus (23 pg) and Necturus maculosus (52 pg) of the ...

journal_title：Chromosoma

authors： Baldari CT,Amaldi F

更新日期：1976-12-06 00:00:00

abstract：:Evidence is presented that chromosome ends are attached to the nuclear envelope prior to the formation of axial cores during early meiotic prophase in the grasshopper Brachystola magna. The attachment sites of distal and proximal chromosome ends are clustered in a small region of the inner nuclear envelope resulting i...

journal_title：Chromosoma

authors： Church K

更新日期：1976-11-29 00:00:00

abstract：:Replication times for all important chromosome bands, of both types R and Q (277 structures) are analysed. The R-bands form a group of structures whose DNA replicates during the early S-phase, while the DNA situated in the Q-bands replicates during the late S-phase. There may not exist overlapping between replication ...

journal_title：Chromosoma

authors： Dutrillaux B,Couturier J,Richer CL,Viegas-Péquignot E

更新日期：1976-10-12 00:00:00

abstract：:The DNA coding for 28 S and 18 S ribosomal RNA, including the spacer regions, has been isolated from calf (Bos taurus) thymus gland. The method used included shearing of the total DNA to a highly homogeneous size population, selective heat denaturation and S1 nuclease treatment to remove single stranded DNA. Repeated ...

journal_title：Chromosoma

authors： Blin N,Stephenson EC,Stafford DW

更新日期：1976-10-12 00:00:00

abstract：:Male hybrids of the cross D. azteca X D. athabasca are larger (hybrid giant males) than their parents, whereas hybrid females are of the same size as the parental species. Microspectrophotometric measurements have shown that the larval polytene salivary gland chromosomes of hybrid giant males undergo one more endorepl...

journal_title：Chromosoma

authors： Meer B

更新日期：1976-09-10 00:00:00

abstract：:BrdU-33258 Hoechst techniques have been used to characterize DNA replication patterns in lymphocytes from hunam females with supernumerary or structurally abnormal X chromosomes. Fluorescence analysis permits identification of late replicating X chromosomes in a very high proportion of cells and affords a high resolut...

journal_title：Chromosoma

authors： Latt SA,Willard HF,Gerald PS

更新日期：1976-08-17 00:00:00

abstract：:The distribution of constitutive heterochromatin has been investigated in four chromosomal races of the grasshopper Caledia captiva (2n=23 male/24 female) by the C-banding technique. Each of the four races was found to have a distinctive banding pattern which is associated with the inter-racial differences in chromoso...

journal_title：Chromosoma

authors： Shaw DD,Webb GC,Wilkinson P

更新日期：1976-06-30 00:00:00

abstract：:Mitomycin C-induced sister chromatic exchange and quadriradial formation were studied in chromosomes from Muntiacus muntjac fibroblasts and A9, a transformed mouse cell line. We present the first direct cytological evidence for the induction of true somatic recombination involving homologous chromosomes. Analysis of t...

journal_title：Chromosoma

authors： Huttner KM,Ruddle FH

更新日期：1976-06-30 00:00:00

abstract：:The salivary chromosomes of the l(3)tl mutant of D. melanogaster are considerably thicker and shorter than those of normal larvae. In most nuclei, chromosome shortening is associated with morphological changes of two types. a) The bands lose their distinctive pattern and become loose. The chromosome appears as a granu...

journal_title：Chromosoma

authors： Zhimulev IF,Belyaeva ES,Lychev VA

更新日期：1976-04-21 00:00:00

abstract：:The method of ultrathin sections of unsquashed salivary gland polytene chromosomes of Ch. thummi was applied to their ultrastrual mapping. There was a good agreement between electron micrographs and Hägele's light microscopic map (1970) with respect to the pattern and number of bands. 94% of bands were identified in l...

journal_title：Chromosoma

authors： Kiknadze II,Perov NA,Chentsov YS

更新日期：1976-03-31 00:00:00

abstract：:The genus Caledia acontains two species. C. species nova 1 is restricted to the Oriomo Plateau of S. W. Papua and has a complement of twelve telocentric chromosomes. The second species C. captiva has a much wider distribution pattern--from S.W. Papua in the North, down the entire Eastern seaboard of Australia to South...

journal_title：Chromosoma

authors： Shaw DD

更新日期：1976-02-23 00:00:00

abstract：:After conjugation in the ciliated protozoan, Oxytricha, polytene chromosomes are formed during the development of a macronucleus from a micronucleus. Here we report a microscopic study of these chromosomes and an analysis of their DNA. The polytene chromosomes of Oxytricha bear a strong morphological resemblance to th...

journal_title：Chromosoma

authors： Spear BB,Lauth MR

更新日期：1976-01-27 00:00:00

abstract：:Quinacrine (Q-band) and centromeric heterochromatin (C-band) patterns of metaphase chromosomes of two subspecies of Mus musculus were compared. M.m. musculus (the laboratory mouse) and M.m. molossinus (a subspecies from Southeast Asia) had similar Q-band patterns along the length of the chromosomes, but differences we...

journal_title：Chromosoma

authors： Dev VG,Miller DA,Tantravahi R,Schreck RR,Roderick TH,Erlanger BF,Miller OJ

更新日期：1975-12-29 00:00:00

abstract：:In order to induce chromosomal rearrangements, males were exposed to x-rays and then mated to non-irradiated females. The number of each type of structural alteration was determined by examination of the polytene chromosomes of the F1 progeny. -- A comparison of the results with similar studies made on Drosophila reve...

journal_title：Chromosoma

authors： Israelewski N

更新日期：1975-12-10 00:00:00

abstract：:Macronuclear DNA was isolated from purified macronuclei of Paramecium aurelia and the size distribution was determined with regard to growth phase and method of extraction. DNA molecules as long as 105 microns and as short as 0.2 microns were observed. It was concluded that the method of extraction affected the observ...

journal_title：Chromosoma

authors： Cummings DJ

更新日期：1975-12-10 00:00:00

abstract：:In situ hybridization with 3H 18S and 28S ribosomal RNA from Xenopus laevis has been used to study the distribution of DNA sequences coding for these RNAs (the nucleolus organizing regions) in the genomes of six mammals. Several patterns of distribution have been found: 1) A single major site (rat kangaroo, Seba's fru...

journal_title：Chromosoma

authors： Hsu TC,Spirito SE,Pardue ML

更新日期：1975-11-20 00:00:00

abstract：:Chinese hamster cells were grown for 1+ and 2+ cell cycles in the presence of BrdU and then treated by the sister chromatid differential staining technique (SCD). Those regions of a chromosome which had replicated twice in the presence of BrdU were pale staining and by selecting appropriate metaphase cells an accurate...

journal_title：Chromosoma

authors： Crossen PE,Pathak S,Arrighi FE

更新日期：1975-11-11 00:00:00

abstract：:The interaction of Hoechst 33258 with DNA has been examined to help clarify the mechanisms of banding. 1. In agreement with previous studies Hoechst fluorescence is enhanced to a greater degree in AT-rich compared to GC-rich DNA. 2. Hoechst causes an increase in the DNA Tm which is greater at the higher AT content of ...

journal_title：Chromosoma

authors： Comings DE

更新日期：1975-10-14 00:00:00