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Sarah Levine 《Culture, medicine and psychiatry》1980,4(2):151-165
Amongst the Gush of southwestern Kenya instances of rape are frequently reported; this was true also in the colonial period and yet it seems that those cases which come to the notice of the authorities are few compared with the numbers which actually occur. While certain features of the traditional culture seem to have encouraged violent sexual assault, because in a patrilocal society miscreants are likely to victimize their relatives, that is women who are sexually taboo, the crime is considered a sacrilegious matter to be dealt with in the family, not by the secular authorities. Given the sacrilegious nature of the act the Gush are convinced that such behavior is involuntary and that the criminal is not a criminal but an afflicted person, motivated by the malevolence of the ancestral spirits or of jealous neighbors and kin. The author uses case material to illustrate various aspects of the Gush belief system in regard to criminal behavior in general and rape in particular. 相似文献
14.
M D Keppler M A Read P J Perry J O Trent T C Jenkins A P Reszka S Neidle K R Fox 《European journal of biochemistry》1999,263(3):817-825
We have used quantitative DNase I footprinting to measure the relative affinities of four disubstituted and two monosubstituted amidoanthraquinone compounds for intermolecular DNA triplexes, and have examined how the position of the attached base-functionalized substituents affects their ability to stabilize DNA triplexes. All four isomeric disubstituted derivatives examined stabilize DNA triplexes at micromolar or lower concentrations. Of the compounds studied the 2,7-disubstituted amidoanthraquinone displayed the greatest triplex affinity. The order of triplex affinity for the other disubstituted ligands decreases in the order 2,7 > 1,8 = 1,5 > 2,6, with the equivalent monosubstituted compounds being at least an order of magnitude less efficient. The 1,5-disubstituted derivative also shows some interaction with duplex DNA. These results have been confirmed by molecular modelling studies, which provide a rational basis for the structure-activity relationships. These suggest that, although all of the compounds bind through an intercalative mode, the 2,6, 2,7 and 1,5 disubstituted isomers bind with their two side groups occupying adjacent triplex grooves, in contrast with the 1,8 isomer which is positioned with both side groups in the same triplex groove. 相似文献
15.
The impact of ticks on pheasant territoriality 总被引:1,自引:0,他引:1
Pheasants are competent reservoir hosts for the Lyme disease spirochaete, Borrelia burgdorferi s.l., and carry large, but highly over-dispersed, infestations of the vector ticks, Ixodes ricinus . The effects of experimental reduction of tick infestation levels on the survival and territorial behaviour of male pheasants were studied. Over three years in two woodlands in southern England, birds were marked individually and half were fitted with a slow-release acaricide, which substantially reduced their tick burdens from March to August. Acaricide treatment affected reproductive success but had no discernible impact on the survival rates of male pheasants. The degree of wattle inflation by males, an indicator of territorial status and a correlate of harem acquisition, was significantly greater among treated males. In each year, a significantly higher proportion of treated (overall 44%) than control (22%) males acquired harems. Males that acquired females ranged over small areas on field edges. By contrast, those with no females ranged more widely in woods and the adjoining fields, increasing their exposure to questing ticks. The relative contribution of such roving males to tick-borne pathogen transmission may thus increase. 相似文献
16.
Low-calcium-response, or Lcr, plasmids of yersiniae are known to promote an in vitro nutritional requirement for 2.5 mM Ca2+ at 37 degrees C which, if not fulfilled, results in cessation of growth with induction of virulence functions (Lcr+). The mechanism whereby Ca2+ regulates this metabolic shift is unknown. Radioactive Ca2+ was not actively accumulated by yersiniae but was excluded by an exit reaction analogous to those described for other bacteria. Nevertheless, cultivation at 37 degrees C with 0.1 mM Ca2+, a level insufficient to prevent restriction of cell division, promoted significantly more binding of the cation by Lcr+ organisms than by plasmid-deficient Lcr- mutants. According, Lcr+ yersiniae may possess unique ligands capable of recognizing Ca2+. 相似文献
17.
Steryl glycosides are the predominant form of sterol at 88% of the total sterol in non-betalain producing calli of Beta vulgaris. The total sterol decreases and sterol form shifts from steryl glycosides to 97% free sterol upon the transition of non-betalain to betalain producing calli. A substantial decrease in stigmasterol (24--ethylcholesta-5,22E-dien-3-ol) and sitosterol (24-ethylcholest-5-en-3-ol) levels is observed during this transition, and alters the ratio of 7:5 sterols. Spinasterol (24- ethyl-5-cholesta-7,22E-dien-3-ol) is the dominant sterol at 43% and 95% of the total sterol in non-betalain producing and betalain producing calli. The level of 22-dihydrospinasterol (24-ethyl-5-cholest-7-en-3-ol) is reduced in both calli to 3% from 25% in leaves. Lanosterol (4,4,14-trimethyl-cholesta-8(9),24-dien-3-ol) and cycloartenol (9,19-cyclopropyl-4,4,14-trimethyl-cholest-24-en-3-ol) were identified in betalain and nonbetalain producing callus respectively. 相似文献
18.
Structural studies of the capsular polysaccharide from Haemophilus pleuropneumoniae serotype 2 总被引:3,自引:0,他引:3
The capsular polysaccharide of Haemophilus pleuropneumoniae serotype 2 (ATCC 27089) is composed of D-glucose (two parts), D-galactose (one part), glycerol (one part), and phosphate (one part). Hydrolysis, dephosphorylation, methylation, enzymic studies, and 1H and 13C nuclear magnetic resonance experiments showed that the polysaccharide is a high molecular weight polymer of a tetrasaccharide repeating units, linked by monophosphate diester and having the following structure: (Formula: see text). 相似文献
19.
Acute exposure of rainbow trout (Salmo gairdneri) to low external calcium (25 microM) caused an immediate but transient increase in plasma epinephrine concentration that may have been related to a concomitant depression of blood pH. Intra-arterial infusion of epinephrine at normal ambient calcium levels (0.35 mM) for 4 h caused circulating levels of epinephrine to rise from 2.9 X 10(-9) to 8.0 X 10(-8) M but did not affect norepinephrine levels, or branchial unidirectional calcium fluxes. Active (ATP-dependent) calcium transport across basolateral plasma membranes prepared from gill epithelial cells was not affected by pretreatment of fish with epinephrine or by direct application of epinephrine or cAMP, in vitro. Epinephrine infusion elevated urine flow rate, decreased urine pH, and increased urine phosphate levels significantly. Net renal calcium efflux increased significantly as a result of the increased urine flow rate. It is concluded that epinephrine does not stimulate branchial calcium uptake or renal conservation of calcium in rainbow trout at normal external calcium levels and therefore we cautiously suggest that epinephrine is unlikely to be involved in calcium balance during periods of exposure to low external calcium. Instead, epinephrine may play a role in compensating the acid-base disturbances and the increased branchial water influx that are associated with exposure to low ambient calcium. 相似文献
20.
J C Ansel T A Luger D Lowry P Perry D R Roop J D Mountz 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(7):2274-2278
Murine and human keratinocytes produce an IL-1-like factor that appears to be similar if not identical to monocyte-derived IL-1. IL-1 may be an important mediator in cutaneous inflammatory responses, however, little is currently known concerning factors that may modulate IL-1 expression in keratinocytes. To address this issue we examined the effect of LPS, UV, and the cell differentiation state on murine keratinocyte IL-1 mRNA expression. Our results indicated that as with the murine P388D1 monocyte cell line, PAM 212 keratinocytes constitutively express abundant amounts of IL-1 alpha mRNA. On exposure to LPS (100 micrograms/ml) for 8 h there was more than 10 times the increase in PAM 212 IL-1 alpha mRNA which was accompanied by a sixfold increase in supernatant IL-1 activity. Similarly UV irradiation had a significant effect on keratinocyte IL-1 alpha expression. High dose UV (300 mJ/cm2) inhibited PAM 212 IL-1 alpha expression at 4, 8, 24, 48 h post-UV whereas a lower dose of UV (100 mJ/cm2) inhibited UV at 4 and 8 h post-UV, but induced IL-1 expression at 24 and 48 h post-UV. The expression of IL-1 alpha varied with the differentiation state of the keratinocytes. Freshly removed newborn murine keratinocytes were found to constitutively express IL-1 alpha mRNA. Keratinocytes grown in low [Ca2+] tissue culture media (0.05 mM) for 6 days, functionally and phenotypically become undifferentiated and express increased quantities of IL-1 alpha mRNA, whereas cells grown in high [Ca2+] media (1.2 mM) for 6 days become terminally differentiated and IL-1 expression ceased. Keratinocytes cultured for 3 days in low [Ca2+] conditions expressed an intermediate level of IL-1 alpha. In contrast, little or no IL-1 beta mRNA was detected in either the PAM 212 cells or newborn murine keratinocytes. Thus LPS, UV, and cell differentiation state have a significant effect on expression of IL-1 alpha in murine keratinocytes. 相似文献