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1.
R. G. Kessel 《Cell and tissue research》1965,66(1):106-117
Summary Electron microscope studies were made on the test cells which comprise a part of the follicular envelope in the ovary of the tunicate Ciona. During development the cells become filled with secretory granules. The Golgi complex is well developed and usually centrally located in the cells. The morphological variations shown and described strongly suggest that the Golgi complex is mainly concerned with the origin of the secretion in these cells.Supported by research grants (GM-9229, 9230) from the National Institute of General Medical Science, United States Public Health Service.This investigation was supported by a Public Health Service Research Career Program Award (1-K3-GM-11, 524) from the National Institute of General Medical Sciences. 相似文献
2.
The transport of oxygen in a hemoglobin-saturated medium is theoretically investigated using classical transport theory. It
is found that all the chemical complexes can be expressed as a single function of oxygen pressure. A potential difference
together with apH shift is predicted to occur across the medium.
This research was supported by the United States Public Health Service Training Grant No. 5-T1-GM-833 from the National Institute
of General Medical Sciences.
This research was supported by a United States Public Health Service Research Career Program Award 5-K6-GM-18,420 from the
National Institute of General Medical Sciences. 相似文献
3.
Robert A. Wijsman 《Bulletin of mathematical biology》1952,14(2):121-126
A formula is derived for the probabilityP(r
1) that two molecules, originally at a distancer
1 from each other and moving in an infinite scattering and absorbing medium, will eventually collide with each other.
Public Health Service Research Fellow of the National Cancer Institute. 相似文献
4.
Summary L cells were grown in spinner cultures in a defined medium consisting of Waymouth medium MB752/1 (19) supplemented with 2
mg of fatty acid-free bovine serum albumin (BSA) per ml and 5 μg of oleate per ml (WO5 medium). Growth in WO5 medium was comparable to spinner L cell growth in two serum-containing media. The optimal concentration of oleate in the
WO medium was 5 to 10 μg per ml. The use of 20 to 80 μg of oleate per ml of medium resulted in lower peak populations and
earlier declines in viable cell counts. Cell death occurred rapidly in WO160 medium. Cell growth in WO medium containing 5 to 80 μg of oleate per ml was well above the level of growth observed when
no oleate was present in the medium. Since the total lipid and fatty acid compositions of the BSA used in this study have
been characterized by the authors, the WO medium may be considered a defined medium. L cells have been continuously maintained
in spinner cultures in WO5 medium for over 50 passages with no major variation in the growth pattern. A 1000-fold increase inChlamydia psittaci strain meningopneumonitis, with a peak titer of 9.3×107 plaque-forming units per ml, was observed when the chlamydial agents were grown in spinner L cells in WO5 medium.
This investigation was supported by Public Health Service Research Grant HE 08214 from the Program Projects Branch, Extramural
Programs, National Heart and Lung Institute; The World Health Organization; and The Hormel Foundation. 相似文献
5.
The amino acid sequence of the high-activity equine erythrocyte carbonic anhydrase (CA-II) has been determined. Two different N-termini are noted, the C1 form having an N-acetyl-serine and the C2 form an N-acetyl-threonine. The sequence of the equine enzyme is most homologous to the human CA-II isozyme, with 224 of the 259 residues being identical.This investigation was supported in part by United States Public Health Service Grant CA-1786 from the National Cancer Institute. 相似文献
6.
A method for the starch gel electrophoresis of human L-glutamate dehydrogenase (GLUD) is described, as is the tissue distribution of GLUD detected by this method. Extracts of livers from 200 Whites were analyzed without demonstration of an electrophoretic variant. The molecular size was estimated to be 330,000 and the isoelectric point pH 4.83.This investigation was supported by Public Health Service Grant No. 1 F22 CAO2083-01 of the National Cancer Institute. 相似文献
7.
Richard M. Marwin 《Mycopathologia》1962,18(4):259-263
Summary The growth ofCryptococcus neoformans andCandida albicans in Sabouraud's dextrose broth with added surface-active agents was measured by nephelometric methods. The surface-active agents was measured by nephelometric methods. The surface-active agents utilized were Polyethylene glycol 400 monolaurate, Pluronic L 64, and Mulsor 224. These three compounds definitely stimulated the growth of the above organisms as indicated in the accompanying tables. The nephelometric runs were corroborated with plate counts taken at suitable intervals.This project was supported by Research Grant E-1045(R) of the National Institute of Health, United States Public Health Service. 相似文献
8.
Summary Isolated fixed liver nuclei of Rana pipiens were stained at varied pH by the acid dye, fast green FCF. The amount of nuclear protein, as determined by cytophotometric measurement of the relative absorption of the stained nuclei, was found to increase in proportion to nuclear size when the pH of the dye solution was below 4.0. Relative absorption was found to be independent of nuclear size, but proportional to the pH of the staining solutions in the pH range between 5.0 and 7.0, These data suggest a change in composition and/or structure of the nuclear protein with increasing nuclear size.This investigation was supported by a grant from the U.S. Public Health Service, GM-10003-04.Post-Doctoral Trainee under U.S. Public Health Training Grant to the Department of Pathology, University of Florida, NIH-GM-1142-03.Supported by a Career Development Award from the National Institute of Child Health and Human Development, K3-HD-6176-04. 相似文献
9.
Summary The various agents which can cause the initiation of cell division in the egg of the wormChaetopterus all cause an increase in the viscosity of the interior protoplasm. These agents include hypertonic solutions, isotonic potassium chloride solutions, cold, heat, acid, alkali, ether and ultraviolet radiation.This investigation was supported by a research grant from the National Cancer Institute, National Institutes of Health, Public Health Service. 相似文献
10.
R. G. Kessel 《Cell and tissue research》1967,76(1):21-30
Summary The vacuolization of the outer follicle cells which accompanies maturation of the oocytes of the tunicates Ciona intestinalis and Molgula manhattensis is associated with the dissolution of heterogeneous secretion granules in these cells. The secretion granules, in turn, have a dual origin with one component derived from the endoplasmic reticulum while the other component arises in association with the Golgi complexes. Stages in the morphogenesis of secretion are described.This study was supported by a research grant (GM-09229) and a Career Development Award from the National Institute of General Medical Science, United States Public Health Service. 相似文献
11.
A chemically defined medium satisfactory for growth of a number of laboratory strains and recent isolates ofNeisseria gonorrhoeae has been devised. It contains inorganic salts, dextrose, guanine, cytosine, B-vitamin supplement, and the following amino acids:l-arginine,l-aspartic acid,l-cystine,l-isoleucine,l-leucine,l-proline,l-threonine, andl-valine.Nine of the eleven strains grew satisfactorily in this medium without being provided supplemental CO2 during incubation, and a tenth strain grew in the medium supplemented with glutamine. No single B-vitamin or purine or pyrimidine base was essential for growth of any of the strains, but some combinations of them were stimulatory. Riboflavin, however, was inhibitory. The strains showed variations in requirements for amino acids. The amino acids which were either essential or stimulatory for one or more of the strains were included in the medium. Those to which the strains responded differently were used at concentrations intermediate between those optimal for growth of one strain and inhibitory for another. Conventional agar was inhibitory, but a purified agar, having a gel strength twice that of conventional agar, was satisfactory. An aqueous solution of 0.1% cysteine and 0.86% NaCl was satisfactory for preparation of inocula.This investigation was supported by a Public Health Service Predoctoral Fellowship (F-FI-GM-24-755-01A1) from the National Institute of General Medical Sciences of the United States Public Health Service to the senior author. 相似文献
12.
An isoleucine auxotroph of Salmonella typhimurium was derived from a merodiploid strain (containing the F-14 episome from Escherichia coli) that contained two copies of the structural genes concerned with isoleucine and valine biosynthesis. A haploid derivative, strain TU6001, having the same growth properties as the original merodiploid mutant was found to have normal biosynthetic enzymes and an altered isoleucyl-tRNA synthetase. The K
m for isoleucine was increased by about 200-fold over that for the wild-type enzyme. All five enzymes in the isoleucine and valine biosynthetic pathway were derepressed relative to wild-type enzyme levels. A partial revertant of strain TU6001 was isolated which had properties that were intermediate between those of the mutant and the wild type (i.e., intermediate growth dependence on exogenous isoleucine, intermediate activity of isoleucyl-tRNA synthetase, and intermediate derepression of biosynthetic enzymes). The properties of strain TU6001 were demonstrated to be simultaneously transferable by transduction (using PLT22 H4 bacteriophage) of a single genetic locus, linked to pyr A, which has been designated ilv S. It is concluded that some function of the isoleucyl-tRNA synthetase is important in repression of the isoleucine and valine biosynthetic enzymes.Supported by grant GM 12522 from the National Institute of General Medical Sciences, U.S. Public Health Service. J. M. B. received a U.S. Public Health Service Postdoctoral Fellowship 1-F02-GM-30, 650-02. 相似文献
13.
A defined medium (MAM) simulating acid mine drainage waters was developed which supported reproducible growth rates of three axenic strains of Euglena mutabilis Schmitz. Growth responses to various pHs and carbon sources were examined under defined culture conditions. A lab strain and two 5eld isolates, tested over pH range 1.5-9.0, grew best under acidic conditions (pH < 5.5) with highest growth rates at pH 3-4. Photoauxotrophic growth rates of all strains at pH 3 were improved significantly over unstirred batch controls by bubbling with air and even more by enrichment with 5% CO2 in air. These results confirmed inorganic carbon limitation in batch culture. Organic carbon substrates were tested as possible carbon supplements in batch culture at pH 3. None of the strains survived in the dark on any of the twenty organic sources added. In the light, the lab strain exhibited some photoheterotrophic growth potential on glucose, sucrose, ethanol, and amino acids but growth was inhibited by acetate. Field strains showed little or no growth improvement with any organic substrate addition. Under simultaneous enrichment with acetate and 5% CO2 acetate continued to be inhibitory. Simultaneous enrichment with glucose and 5% CO2 gave higher yields of the lab strain than with CO2 alone but did not enhance growth of the field strain. We conclude that E. mutabilis is an acidophilic photoauxotroph which appears unable to use organic carbon supplements for growth even under conditions of carbon limitation. 相似文献
14.
Jagdeesh Pyati 《Molecular & general genetics : MGG》1976,146(2):189-190
Summary The sex-linked gene, tuh-1, produces a maternal effect that is associated with the tumorous head abnormality in Drosophila melanogaster. With the aid of various known deletions, tuh-1 has been localized to band 20A1-2 on the salivary chromosome map of the X.Work supported by grant GM 18664-01 from the National Institute of Health, U.S. Public Health Service 相似文献
15.
Five laboratory procedures: 1) immunodiffusion, 2) immunofluorescence, 3) in vitro hair perforation, 4) pigment stimulation, and 5) a urease test were compared for their ability to differentiateT. rubrum fromT. mentagrophytes. Of the physiological tests, thein vitro hair perforation technique was the most reliable for differentiating the two species. With the serological tests, the organisms were not differentiated by immunodiffusion, but if appropriate dilutions of the conjugates were used in immunofluorescence testing, most isolates could be differentiated.A portion of a Dissertation submitted by the senior author to the University of North Carolina in partial fulfillment of the requirements for the degree of Doctor of Public Health in the School of Public Health. Training was provided by the Laboratory Director's Program which is supported by Training Grant TO1 GM 00567-07 from the National Institute of General Medical Sciences, National Institutes of Health, United States Public Health Service. The laboratory research was performed at the Laboratory Division, Center for Disease Control, under the supervision of William Kaplan. 相似文献
16.
Summary When Pl phages grown on strain Bs12 (HCR) were used to infect exr strains Bs2, 4 and 7, and the reverse, a significant increase in survivors of ultraviolet radiation was observed over those found in selfing experiments. No such increase in survivors was found when Pl grown on each of the exr strains was used to infect each of the other exr strains. Only 1% of the survivors of UV treatment were stably resistant to UV. These data are considered a demonstration of complementation between the malB-linked, UV sensitivity genes of Bs12 (uvrA) and Bs2, 4 and 7 (exr).This work was carried out under Public Health Service Grant CA 05687-08 from the National Cancer Institute.Recipient of a Public Health Service Career Development Award. 相似文献
17.
The evidence of gene duplication for S-form NADP-linked isocitrate dehydrogenase in carp and goldfish 总被引:4,自引:0,他引:4
In the present paper, allelic polymorphism for electrophoretic variants of supernatant-form of NADP-linked isocitrate dehydrogenase (S-form IDH) was described in the surf smelt (Hypomesus pretiosus), the goldfish (Carassium auratus), and the carp (Cyprinus carpio). As in most other vertebrates including mammals, S-form IDH of the smelt was specified by a single gene locus. The goldfish and the carp, on the other hand, were endowed with two separate gene loci for S-form IDH. This apparent gene duplication was attributed to tetraploid origin of the goldfish and carp.This work was supported in part by a grant (CA 05138) from the National Cancer Institute, U.S. Public Health Service.Dr. Antonio Quiroz-Gutierrez is a postdoctorate fellow of the Institute for Biomedical Studies of the City of Hope Medical Center; he has also received support from the Ministry of Work, Mexico. 相似文献
18.
Hsiao-Chen Chang Oliver W. Jones Christy Bradshaw Siddhartha Sarkar Richard P. Porreco 《In vitro cellular & developmental biology. Plant》1981,17(1):81-90
Summary Ficoll-Paque isopycnic centrifugation was used as a preparative procdure for amniotic fluid (AF) cells prior to tissue culture.
This technique serves to reduce contaminating erythrocytes and also enhances cell growth or mitotic indices. The technique
described in this report yields three subfractions designatedaas a turbid interphase layer (F-2), a middle cell layer (F-3),
and a bottom pellet (F-4). The middle cell layer (F-3) demonstrated better cell growth and higher mitotic index than any of
the other fractions or control unfractionated amniotic fluid cells. The use of Ficoll-Paque isopycnic preparative centrifugation
of amniotic fluid cells is a valuable adjunct in cell culture for cytogenetic analysis. This may be especially true when amniotic
fluid contains large numbers of erythrocytes.
Hsiao-chen Chang was supported by National Research Service Award 1 F32 AM HD 05887-01 from the National Institute of Arthritis,
Metabolism, and Digestive Diseases; U. S. Public Health Service, National Institutes of Health. This work was supported in
part by USPHS Human Biochemical Genetics Program (G177 17702-9) and the State of California, Department of Public Health,
Prenatal Diagnosis Program (79-00016). 相似文献
19.
A new RNA synthesis mutant of E. coli 总被引:6,自引:0,他引:6
David Patterson Mark Weinstein Sergio Marshall David Gillespie 《Biochemical genetics》1971,5(6):563-578
A temperature-sensitive mutant of E. coli is described. At the nonpermissive temperature, the capacity for RNA and protein synthesis decreases logarithmically in the mutant. The mutant is unable to support the growth of f2 or T7 virus, even at the permissive temperature. The temperature-sensitive mutation maps approximately 1 away from rif
r in E. coli and therefore affects a gene previously undescribed. The temperature sensitivity is suppressed by sublethal concentrations of rifampicin. Moreover, in rif
r Ts double mutants, the T
s mutation suppresses rif
r and vice versa. The partially purified RNA polymerases from mutant and wild-type cells have different temperature and salt optima.This research was supported by Public Health Service grant GM-14368 from the National Institute of General Medical Sciences and by grant IN-29 from the American Cancer Society. One of us (D.P.) is a predoctoral trainee, supported by a National Science Foundation Graduate Traineeship Program and by a National Institutes of Health Predoctoral Research Fellowship. S. Marshall is supported by LASBAU. 相似文献
20.
Summary Intracellular arabitol and mannitol accumulation is under nutritional and temporal control during arthrospore germination, vegetative growth, and arthrospore formation in Geotrichum. Arabitol is not produced if the glucose concentration in the medium is low. Arabitol is produced in large quantities in the cells if the carbon source is acetate or if the glucose level is above 10%. Low levels of glucose do not repress acetate induction of arabitol formation. Arabitol began to accumulate during spore swelling and vegetative growth in the presence of acetate. Mannitol appeared to serve as a carbon and energy reserve during starvation and arthrospore germination; the concentration of mannitol in vegetative cells remained barely detectable until sporulation commenced.This research was supported by National Science Foundation Grant GB-8327 and Public Health Service Grant Al-04603-09 to D.J.N. 相似文献