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11.
12.
Robyn Kliger 《Culture, medicine and psychiatry》1994,18(2):215-245
The aim of this ethnographic work is twofold: first, to document the specifics of the illness experience within the highly controlling milieu of a religious cult; second, to explore the connection between somatization and social control in this particular context. Anthropologists have long realized that in order to comprehend disease etiology, one must examine both biological and sociocultural processes, as both are implicated in the production of illness. Illness experiences of those members of the cult described here appeared to be direct responses to extreme intrapsychic and social control: that is, members were required to be celibate, unmarried, and detached from their pre-cult identity and the emotional support structure of family and friends. Additionally, members were subjected to constant surveillance by peers and were often punished for expressing views that were in conflict with the ideology of the leader, thereby encouraging the somatization of distress. This research is based upon two years of participant observation within the milieu, during which time more than 100 participants were interviewed; however, this paper specifically discusses in-depth interviews with eight individuals whose health problems exemplify those experienced by other members of the cult.Here of late everybody is getting on my nerves so bad. It's no wonder my leg hurts all the time. I guess it knows my heart sure can't hold all the hurt in it. So I guess it's trying to help out... from the novelClover, by Dori Sanders 相似文献
13.
RasG protein accumulation occurs just prior to amoebae emergence during spore germination in Dictyostelium discoideum 总被引:1,自引:0,他引:1
Meenal Khosla George B. Spiegelman Gerald Weeks Todd W. Sands Kiran J. Virdy David A. Cotter 《FEMS microbiology letters》1994,117(3):293-298
Abstract RasG protein levels in dormant and germinating spores of Dictyostelium discoideum strains JC1 and SG1 were estimated by Western blotting. Ras Glevels were very low in dormant spores and remained low during the lag period, regardless of whether spores were heat activated or treated with autoactivator during the early stages of spore germination. RasG levels increased late during spore swelling just prior to the emergence stage of germination. These data are consistent with a requirement for RasG during vegetative growth. 相似文献
14.
Cheryl D. Helgason Lianfa Shi Arnold H. Greenberg Yufang Shi Peter Bromley Thomas G. Cotter Douglas R. Green R. Chris Bleackley 《Experimental cell research》1993,206(2)
Cytotoxic T lymphocyte (CTL)-mediated lysis is accompanied by fragmentation of target cell DNA into an oligonucleosome ladder, a hallmark of apoptosis. Is this a fortuitous coincidence, or could CTL be inducing lysis by activation of the suicide signal? In this report we demonstrate that CTL-mediated target cell death can be blocked with the drug aurintricarboxylic acid (ATA). The abrogation of death correlates with the inhibition of DNA fragmentation. While ATA prevented DNA fragmentation, it failed to significantly alter protein, RNA, or DNA synthesis in the cell lines over the dose range used. In addition, there was no inhibition of cell-cell interaction or granule exocytosis during CTL-mediated killing. ATA also significantly inhibited the cytolysis and DNA fragmentation mediated by isolated cytolytic granules, as well as the granular protein fragmentin. We developed an assay in which target cells could be separated from CTL after binding and programming for lysis. Once they had received the "kiss of death," target cells could be rescued from lysis (as indicated by inhibition of DNA fragmentation and increased target cell viability) by treatment with ATA. These results suggest that ATA blocks target cell death by inhibition of DNA fragmentation, and further, that chromatin degradation is a cause rather than a result of cell death in CTL-mediated lysis. 相似文献
15.
Margaret B. Fleming Lauren Stanley Robyn Zallen Matthew T. Chansler Lars A. Brudvig David B. Lowry Marjorie Weber Frank W. Telewski 《American journal of botany》2023,110(11):e16250
Premise
In 1879, Dr. William Beal buried 20 glass bottles filled with seeds and sand at a single site at Michigan State University. The goal of the experiment was to understand seed longevity in the soil, a topic of general importance in ecology, restoration, conservation, and agriculture, by periodically assaying germinability of these seeds over 100 years. The interval between germination assays has been extended and the experiment will now end after 221 years, in 2100.Methods
We dug up the 16th bottle in April 2021 and attempted to germinate the 141-year-old seeds it contained. We grew germinants to maturity and identified these to species by vegetative and reproductive phenotypes. For the first time in the history of this experiment, genomic DNA was sequenced to confirm species identities.Results
Twenty seeds germinated over the 244-day assay. Eight germinated in the first 11 days. All 20 belonged to the Verbascum genus: Nineteen were V. blattaria according to phenotype and ITS2 genotype; and one had a hybrid V. blattaria × V. thapsus phenotype and ITS2 genotype. In total, 20/50 (40%) of the original Verbascum seeds in the bottle germinated in year 141.Conclusions
While most species in the Beal experiment lost all seed viability in the first 60 years, a high percentage of Verbascum seeds can still germinate after 141 years in the soil. Long-term experiments such as this one are rare and invaluable for studying seed viability in natural soil conditions. 相似文献16.
17.
George L. Gabor Miklos Marion J. Healy P. Pain A. J. Howells Robyn J. Russell 《Chromosoma》1984,89(3):218-227
A recombinant Charon 4 bacteriophage has been isolated on the basis of RNAs which are enriched in the head of the adult Drosophila melanogaster and hence are likely to be of neural origin. The cloned insert maps to the near vicinity of the uncoordinated locus in polytene chromosome band 19E8. This band is within the transition zone between the euchromatic and heterochromatic regions of the X chromosome, a region which has been well characterized cytogenetically. The insert contains both repetitious and low copy number sequences, some of which vary extensively in both frequency and restriction fragment size between different laboratory strains. One particular family of moderately repeated sequences occurs predominantly in divisions 19 and 20 of the X chromosome and perhaps the distally located X heterochromatin. The molecular landscape surrounding the initial entry point contains many repeated sequences and is thus unlike those observed in most published chromosomal walks. The possible significance of the presence of repeated sequence families in the distinct properties of this region are discussed. 相似文献
18.
19.
An analysis of metabolism by measurement of respiratory quotient values indicates that reduced substances, such as lipids and/or amino acids, are the primary respiratory substrates of dormant Dictyostelium discoideum spores. The spores appear to consume both reduced substances and carbohydrates during the swelling stage of germination. The respiration of emerged myxamoebae is again dominated by the consumption of reduced substances. The pool of trehalose remains largely intact during heat-induced activation and also during postactivation lag. The initiation of spore swelling is accompanied by a decrease in the trehalose pool; the majority of trehalose is consumed before late spore swelling. Upon placing heat-activated spores under restrictive environmental conditions, swelling and trehalose hydrolysis are both prevented. Release from these conditions results in rapid swelling and hydrolysis of trehalose. Trehalase, the enzyme responsible for trehalose breakdown, is present in dormant spores at basal levels. This preformed enzyme is responsible for the hydrolysis of trehalose even though there is a significant increase in trehalase activity with the emergence of myxamoebae. RNA and protein synthesis inhibitors do not prevent trehalose hydrolysis or spore swelling. It is concluded that oxidation of reduced substances occurs in dormant, activated, and swollen spores, as well as in emerged myxamoebae of D. discoideum. Carbohydrate utilization dominates over the oxidation of reduced substances only during the swelling stage of germination. 相似文献
20.
J T Kindt A Woods B M Martin R J Cotter Y Osawa 《The Journal of biological chemistry》1992,267(13):8739-8743
Recent studies have shown that a protein-bound heme adduct formed from the reaction of BrCCl3 with myoglobin was due to bonding of the proximal histidine residue through the ring I vinyl of a heme-CCl2 moiety. The present study reveals that BrCCl3 also reacts with the heme of reduced human hemoglobin to form two protein-bound heme adducts. Edman degradation and mass spectrometry provided evidence that these protein-bound heme adducts were addition products in which heme-CCL2 or heme-CCl3 were bound to cysteine residue 93 of the beta-chain of hemoglobin. It appeared that the cysteine residue was bonded regiospecifically to the ring I vinyl group of the altered heme moiety, because the nonprotein-bound products of the reaction included the beta-carboxyvinyl and alpha-hydroxy-beta-trichloromethylethyl derivatives of the ring I vinyl moiety of heme. The absorption spectra of the protein-bound adducts in both the oxidized and reduced states were highly similar to those described for hemichromes, which are thought to be involved in the formation of Heinz bodies and subsequent red cell lysis. 相似文献