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In-depth interviews were conducted among 50 subjects residing in the industrial town of Newcastle, Australia. Half of these subjects were from the general population and half were currently seeking counselling for personal/family problems. None of the subjects were receiving any medical care at the time of interview, though seven had done so during the episode of distress they were discussing. The study shows that while the subjects psychologized their problems, members of both groups tended to somatize at a rate proportional to the level of distress. Subjects were unaware of any relationship between the distress they were experiencing and their physical complaints. The results of this study support previous research which argues that those experiencing distress and those who tend to introspect are also those who are likely to amplify somatic symptoms. At the same time these results depart from findings in the United States which suggest that in the West, people learn to express social and personal distress in psychological terms,, thereby reducing the level of somatization. Though not representative of the population as a whole, the findings raised questions warranting further study. 相似文献
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Steady flow studies were conducted in a transparent canine aortic cast. The cast segment stretched from the aortic valve to beyond the renal arteries and included all major branches. Flow was visualized by analysis of dye streaklines. Flow rates for basal and exercising cardiovascular states were simulated. The Reynolds numbers in the ascending aorta for basal and exercising conditions were 900 and 1587 respectively. Aortic core flow was laminar in basal simulations. Disturbed flow commenced in the upper descending aorta with exercising flow rates. Separation zones existed along the inner curvature of the aortic arch and the proximal walls of the brachiocephalic, left subclavian, and coeliac arteries. Such zones may exist over a portion of the cardiac cycle. If either renal artery was occluded, then a vortex formed. This vortex is associated with high shear regions which correlate well with sites where sudanophilic lesions have been reported in cholesterol-fed nephrectomized rabbits. 相似文献
5.
Method for Assessing the Frequency of Transfer of an R Factor on Solid Media and for Isolating Cells of the Donor Type from a Predominantly Repressed Culture
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A method for assessing the incidence of R factor transfer on solid media is described. The method gives values similar to those obtained with conventional techniques but allows the derepressed cells from a predominantly repressed population to be isolated. 相似文献
6.
Eleven strains of the crown gall organism, Agrobacterium tumefaciens, tested by intraperitoneal injection into mice, were lethal within 48 hr. Five other species had some lethal strains. The lethal effect of A. tumefaciens appeared to be the result of a toxic rather than an infectious process, since histopathological anomalies were not found in mice injected with live cultures and since heat-killed cultures were lethal. The murine toxin disappeared when A. tumefaciens was grown at 36 C and reappeared when the organism was subsequently incubated below 30 C. The murine toxin itself was not inactivated by exposure to 100 C for 30 min. The toxin was associated with the cells and was not excreted into the medium. Centrifugal fractionation revealed that the toxin was associated with the smaller cells in 3-day stationary-phase cultures. These data suggested a possible relationship between toxin production and the production of the agents responsible for the initiation of plant tumors. 相似文献
7.
Nonspecific reactions of a commercial enzyme-linked immunosorbent assay kit (TECRA) for detection of staphylococcal enterotoxins in foods. 总被引:7,自引:4,他引:3
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A staphylococcal enterotoxin visual immunoassay kit (TECRA) has recently become commercially available. Since the kit is an enzyme-linked immunosorbent assay system equipped with polyvalent antisera against staphylococcal enterotoxin types A to E (SEA to SEE) and the test is simple and rapid to perform (4 h), it has been widely used for screening purposes. In this study, the sensitivity of the kit for detection of SEA, SEB, and SEC in ham, cheese, and mushrooms was similar to those of kits based on an enzyme immunoassay and reversed passive latex agglutination: 0.75 to 1.0 ng of SEA per ml, 0.5 to 0.75 ng of SEB per ml, and 1.0 to 1.25 ng of SEC per ml. However, the TECRA kit showed nonspecific reactions with food samples contaminated by microorganisms other than Staphylococcus aureus, such as Enterobacter agglomerans, Enterobacter cloacae, Proteus mirabilis, Pseudomonas aeruginosa, and Serratia marcescens. The substance contributing to the false-positive results differed from true staphylococcal enterotoxins in that it was (i) heat labile (completely inactivated by heating for 2 min at 100 degrees C, whereas true staphylococcal enterotoxins were inactivated by about 10% with this treatment), (ii) lower in molecular weight than staphylococcal enterotoxins, and (iii) not bound to a copper chelate Sepharose gel (all of the substance remained in the unbound wash fraction, whereas staphylococcal enterotoxins were quantitatively bound to the gel). The problem of false-positive results with the TECRA kit could be resolved by heat treatment (2 min at 100 degrees C) or by cleanup procedures involving metal chelate affinity chromatography with copper chelate Sepharose for 4 h before use of the TECRA kit. 相似文献
8.
Teresa L. Johnson Mary Pat Moyer 《In vitro cellular & developmental biology. Plant》1990,26(11):1095-1100
Summary Normal human colon mucosa cells and cells obtained from histologically normal tissues near that cancer were fused with human
colon cancer cells. Resultant hybrid populations of normal and malignant cell fusions behaved as nonmalignant cells in culture,
were unable to grow in soft agar, did not express tumor-associated antigens, and were nontumorigenic in nude mice. Autofusion
of the cancer cell population led to a phenotype intermediate between normal and malignant cells. That is, the cultures had
a much lower plating efficiency in soft agar, and the tumors had a longer latency and slower growth rate in nude mice. This
is the first cell culture system to demonstrate that normal epithelial cells can suppress malignancy of their autologous cancer
cells, and is a prelude to more extensive studies of genetic events involved in malignant conversion of human colonic epithelium.
This study was supported by The University of Texas Health Science Center at San Antonio Center for Human Cell Biotechnology
and a graduate student stipend (T. J.) from the Department of Cellular and Structural Biology. 相似文献
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10.
The NAD-dependent oxidation of ethanol, 2,3-butanediol, and other primary and secondary alcohols, catalyzed by alcohol dehydrogenases derived from Penicillium charlesii, was investigated. Alcohol dehydrogenase, ADH-I, was purified to homogeneity in a yield of 54%. The enzyme utilizes several primary alcohols as substrates, with Km values of the order of 10?4m. A Km value of 60 mm was obtained for R,R,-2,3-butanediol. The stereospecificity of the oxidation of 2-butanol was investigated, and S-(+)-2-butanol was found to be oxidized 2.4 times faster than was R-(?)-2-butanol. The reduction of 2-butanone was shown to produce S-(+)-2-butanol and R-(?)-butanol in a ratio of 7:3. ADH-I is the primary isozyme of alcohol dehydrogenase present in cultures utilizing glucose as the sole carbon source. The level of alcohol dehydrogenase activity increased 7.6-fold in mycelia from cultures grown with glucose and 2,3-butanediol (0.5%) as carbon sources compared with the activity in cultures grown on only glucose. Two additional forms of alcohol dehydrogenase, ADH-II and ADH-III, were present in the cultures supplemented with 2,3-butanediol. These forms of alcohol dehydrogenase catalyze the oxidation of ethanol and 2,3-butanediol. These data suggest that P. charlesii carries out an oxidation of 2,3-butanediol which may constitute the first reaction in the degradation of 2,3-butanediol as well as the last reaction in the mixed-acid fermentation. Alcohol dehydrogenase activities in P. charlesii may be encoded by multiple genes, one which is expressed constitutively and others whose expression is inducible by 2,3-butanediol. 相似文献