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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

INHIBITION OF FERTILIZATION BY FUCUS EXTRACTS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 24-03, page: 0939. / Thesis (Ph.D.)--The Florida State University, 1963.
42

CHARACTERIZATION OF A POLYRIBOSOMAL COMPLEX IN NEUROSPORA CRASSA

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-09, page: 4919. / Thesis (Ph.D.)--The Florida State University, 1964.
43

CYTOCHROME B2 AND D-LACTATECYTOCHROME C REDUCTASE IN RESPIRATION DEFICIENT MUTANTS OF SACCHAROMYCES CEREVISIAE

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 23-05, page: 1494. / Thesis (Ph.D.)--The Florida State University, 1962.
44

CHEMICALLY INDUCED MOSAICISM IN DROSOPHILA

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-01, page: 0039. / Thesis (Ph.D.)--The Florida State University, 1963.
45

MORPHOLOGICAL ASPECTS OF GAMETE CONTACT AND FUSION AND OF SPERM ENTRY INTO OOCYTES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-01, page: 0039. / Thesis (Ph.D.)--The Florida State University, 1963.
46

MUTATION SEGREGATION STUDIES IN NEUROSPORA CRASSA

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 27-08, Section: B, page: 2592. / Thesis (Ph.D.)--The Florida State University, 1966.
47

DNA REPAIR IN HAEMOPHILUS INFLUENZAE: ISOLATION AND CHARACTERIZATION OF AN ULTRAVIOLET SENSITIVE MUTATOR MUTANT (TRANSFORMATION, MISMATCH REPAIR, INACTIVATION)

Unknown Date (has links)
DNA repair in Haemophilus influenzae appears to be quite different from that seen in Escherichia coli in that H. influenzae shows neither "S.O.S." nor "adaptation" phenomena. Repair of DNA lesions in H. influenzae has been seen to occur via recombinational, excision, and mismatch repair pathways acting independently of one another. I have isolated an ultraviolet (UV)-sensitive mutator mutant (mutB1) of H. influenzae Rd which shows deficiencies in both recombinational and mismatch repair pathways. This mutant is sensitive to a variety of DNA damaging agents as well as being hypermutable by alkylating agents and base analogues. MutB1 cells do not show post-UV DNA breakdown but do begin excision after UV irradiation. / Genetic transformation with UV-irradiated DNA on mutB1 recipients shows that high (HE) and low (LE) efficiency markers are transformed at a ratio of 1.0 as in the mismatch repair deficient hex1 mutant; however, kinetics of UV-inactivation experiments indicate that HE markers are sensitized and act as LE markers do on wild type recipients. Thus, the mutB gene product appears to play a role in both DNA repair and genetic transformation. / An E. coli mutant (uvrD) having many similar properties to the mutB1 mutant has recently been shown deficient in DNA helicase II. A model is outlined which presents a role for a DNA helicase in both DNA repair and genetic transformation of H. influenzae. / Source: Dissertation Abstracts International, Volume: 46-10, Section: B, page: 3333. / Thesis (Ph.D.)--The Florida State University, 1985.
48

THE HEAT SHOCK RESPONSES OF NEUROSPORA CRASSA

Unknown Date (has links)
All living organisms, when confronted with a number of different environmental changes, including heat shock, elicit a common and seemingly highly conserved response: the heat-shock response. The response is characterized by the rapid, preferential synthesis and accumulation of heat shock proteins (hsps). The multiplicity of responses of Neurospora crassa to a simple thermal stress has been analysed at several levels, molecular and cellular. / The major changes in gene expression occur in mycelia and conidia as their environmental temperature is increased from normal value (25(DEGREES)C) to those elevated temperature (36-48(DEGREES)C). At least eight hsps were greatly synthesized and simultaneously most of preexisting normal proteins were greatly reduced. Each hsp requires the different range of elevated temperatures and different lengths of time for initiation and maximal synthesis. / The response of Neurospora to heat shock was transient during the continous heat-shock treatment: normal protein synthesis resumes and heat shock protein synthesis decreases. / The heat-shock response was differentially expressed during the germination of conidia. Most of hsps were fully expressed only after 3 hours of pre-germination from dormant conidia. / There is a good correlation between the induction of thermotolerance and increased synthesis of hsps. The transient pattern of induction, development, and decay of thermotolerance was very similar to the pattern of hsp synthesis at the same elevated temperature. / The protocol for isolation of several hsps was developed using combination of two different chromatographic methods, including DEAE-HPLC and SE-HPLC. / DNA sequences of Neurospora nuclear genome were cloned, which are highly expressed in heat-shocked cells.(' ) / Source: Dissertation Abstracts International, Volume: 48-03, Section: B, page: 0643. / Thesis (Ph.D.)--The Florida State University, 1987.
49

MICROTUBULE ORGANIZATION, THE REGULATION OF MICROTUBULE ASSEMBLY AND DISASSEMBLY, AND THE FUNCTIONS OF THE MICROTUBULE-CONTAINING STRUCTURES IN SEA URCHIN EGGS DURING FERTILIZATION AND CELL DIVISION (MOTILITY)

Unknown Date (has links)
Anti-tubulin immunofluorescence microscopy was used to study the structures involved in the first cell cycle in the fertilized sea urchin egg and the regulation of microtubule assembly following fertilization. / Four different microtubule-containing structures were observed in the egg cytoplasm at different times during the first cell cycle. The unfertilized egg was found to be devoid of microtubules. Immediately after fertilization, the sperm aster forms. This structure is transient, and is followed in sequence by the monaster, the streak, and the mitotic apparatus. The possible functions of each of these structures was investigated. / The finding that the unfertilized egg does not contain any polymerized microtubules presented a perfect system to study the regulation of microtubule assembly in vivo. The formation of microtubules in vivo was studied in relation to DNA synthesis cycles, the presence or absence of centrioles, and the Ca('++)-fluxes and pH changes which accompany fertilization. It was determined that of these variables, the change in intracellular pH that accompanies fertilization is absolutely essential for microtubule assembly to commence in the egg cytoplasm. / Investigations were carried out to determine the target or targets which were affected by the pH shift and were then subsequently responsible for making the egg cytoplasm conducive to supporting microtubule assembly. Ca('++)-sensitivity experiments were carried out on the sperm aster microtubules at various pH's and it was found that the microtubules themselves were not made more resistant to Ca('++) ions because of the pH change. From this it was concluded that the change in pH does not act directly on microtubules to support microtubule assembly. The cytoplasmic component that is the target of the pH shift remains to be determined. / Source: Dissertation Abstracts International, Volume: 46-04, Section: B, page: 1051. / Thesis (Ph.D.)--The Florida State University, 1985.
50

ALTERATIONS IN FINE STRUCTURE DURING EMBRYO AND ENDOSPERM DEVELOPMENT IN LETHAL HYBRIDS INVOLVING HIBISCUS COSTATUS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 31-09, Section: B, page: 5185. / Thesis (Ph.D.)--The Florida State University, 1970.

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