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101.

Background:

Nationally representative Canadian data on the prevalence of child abuse and its relation with mental disorders are lacking. We used contemporary, nationally representative data to examine the prevalence of 3 types of child abuse (physical abuse, sexual abuse and exposure to intimate partner violence) and their association with 14 mental conditions, including suicidal ideation and suicide attempts.

Methods:

We obtained data from the 2012 Canadian Community Health Survey: Mental Health, collected from the 10 provinces. Respondents aged 18 years and older were asked about child abuse and were selected for the study sample (n = 23 395). The survey had a multistage stratified cluster design (household response rate 79.8%).

Results:

The prevalence of any child abuse was 32% (individual types ranged from 8% to 26%). All types of child abuse were associated with all mental conditions, including suicidal ideation and suicide attempts, after adjustment for sociodemographic variables (adjusted odds ratios ranged from 1.4 to 7.9). We found a dose–response relation, with increasing number of abuse types experienced corresponding with greater odds of mental conditions. Associations between child abuse and attention deficit disorder, suicidal ideation and suicide attempts showed stronger effects for women than men.

Interpretation:

We found robust associations between child abuse and mental conditions. Health care providers, especially those assessing patients with mental health problems, need to be aware of the relation between specific types of child abuse and certain mental conditions. Success in preventing child abuse could lead to reductions in the prevalence of mental disorders, suicidal ideation and suicide attempts.Child abuse is a major public health problem worldwide with serious adverse effects at later ages. The best estimates of the prevalence of child abuse in Canada come from 2 representative samples from Ontario, 1 from 1990 (Ontario Health Supplement, n = 9953, age ≥ 15 yr)1 and 1 from 2000–2001 (Ontario Child Health Study, n = 1893, age 21–35 yr).2 The 1990 study indicated that 31% of males and 21% of females had experienced physical child abuse, and 4% of males and 13% of females had experienced sexual child abuse.1 Similar trends were noted in data collected in 2000–2001.2 Prevalence of sexual abuse was found to be higher in the Ontario Child Health Study, but this was thought to be related to the inclusion of sexual abuse committed by anyone (e.g., adolescents), rather than only adults, as was the case with the Ontario Health Supplement.1,2 Data from Quebec collected in 2006 indicated that 23% of men and 17% of women had experienced physical child abuse; 10% of men and 22% of women had experienced sexual child abuse; and 22% of men and women had experienced psychological child abuse, including exposure to intimate partner violence.3,4 Unfortunately, these estimates are dated, restricted to only 2 provinces, based on limited assessments of child abuse and, in the case of the Quebec data, involve a low response rate of 30%.Although the association between child abuse and subsequent mental conditions (including disorders, suicidal ideation and suicide attempts) is well established,59 we know little about differential effects associated with several abuse types and specific mental disorders, and we currently have no nationally representative Canadian data. Filling this gap in knowledge would produce evidence-based Canadian findings that could inform policy, prevention and intervention efforts specifically aimed at reducing both child abuse and poor mental health outcomes.Our overall objective was to extend our understanding of the relation between child abuse and mental conditions (i.e., mental disorders, suicidal ideation and suicide attempts)68,1019 with a more detailed examination of child abuse severity and mental health outcomes. We used a nationally representative Canadian sample to examine 3 types of child abuse (physical abuse, sexual abuse and exposure to intimate partner violence) and 14 mental conditions, including suicidal ideation and suicide attempts. The specific research objectives were to estimate the prevalence of 3 types of physical abuse, sexual abuse and exposure to intimate partner violence; to examine the association of mental conditions with types of child abuse and number of child abuse types experienced; and to determine whether sex differences exist in the associations between child abuse and mental conditions.  相似文献   
102.

Background  

Since females often pay a higher cost for heterospecific matings, mate discrimination and species recognition are driven primarily by female choice. In contrast, frequent indiscriminate matings are hypothesized to maximize male fitness. However, recent studies show that previously indiscriminate males (e.g., Drosophila melanogaster and Poecilia reticulata) can learn to avoid heterospecific courtship. This ability of males to discriminate against heterospecific courtship may be advantageous in populations where two species co-occur if courtship or mating is costly.  相似文献   
103.
Three acylated flavonol diglucosides, kaempferol 3-O-β-(6″-O-E-p-coumaroylglucoside)-7-O-β-glucoside; quercetin 3-O-β-(6″-O-E-p-coumaroylglucoside)-7-O-β-glucoside; isorhamnetin 3-O-β-(6″-O-E-p-coumaroylglucoside)-7-O-β-glucoside were isolated from the whole plant aqueous alcohol extract of Lotus polyphyllos. The known 3,7-di-O-glucosides of the aglycones kaempferol, quercetin and isorhamnetin were also characterized. All structures were established on the basis of chemical and spectral evidence.  相似文献   
104.
Reciprocal skin allografts were made between siblings of three successive generations in a family of Xenopus borealis and mutually tolerant animals were mated. In the F3 generation of one subfamily, 92% of the siblings were histocompatible.  相似文献   
105.
106.
Changes in the limiting porosity of cell walls, i.e. the size limit for permeation of neutral molecules through the wall, were studied in several higher-plant cell-suspension cultures. For this purpose, samples of biomass fixed at different cultivation times were investigated using a method based on size-exclusion chromatography of polydisperse dextrans before and after equilibration with the extracted cell clusters. In suspension cultures of Chenopodium album L., Dioscorea deltoidea Wall. and Medicago sativa L., the mean size limit (MSL; critical Stokes' radius for exclusion of neutral polymers from half of the intracellular space) was found to vary between 2.4 and 3.8 nm. It decreased significantly during transition from the growth phase to the stationary phase. In the case of the C. album culture this change was found to be irrespective of whether sucrose in the medium was completely depleted at the end of the growth phase or not. The MSL was kept constant for long periods of the stationary phase if cell viability was maintained by repeated sucrose supplement. In a suspension strain of Triticum aestivum L., the MSL of cell wall permeation was comparatively small (1.75 nm) and remained constant during all cultivation phases. Relations between limiting porosity and cell wall growth, loss of pectic compounds to the medium, cross-linking activities and cell wall stiffening are discussed. Received: 19 December 1996 / Accepted: 23 April 1997  相似文献   
107.
Summary Thirty-three strains of different species of rhizobia were seeded into medium 79 agar. Discs impregnated with 3, 0.3, 0.03 and 0.003%, corresponding to 10, 1, 1/10 and 1/100 the recommended rate of application, of fungicides TMTD, Rhizoctole, Phygon, Ceresan and Orthocide 75 were placed on the seeded agar. After 120 hrs, zones of inhibition were measured. The 3, 0.3 and 0.03% concentrations of the five fungicides were inhibitory to most rhizobia tested in different degrees. The 0.003% level of these fungicides while toxic to certain strains, was not so for others.Deceased August 6, 1968.  相似文献   
108.
Mice were irradiated and infused with BALB/c Friend virus-induced FLD-3 erythroleukemia cells. Growth of the cells was estimated by measuring splenic incorporation of 5-iodo-2'-deoxyuridine-125I 5 days after cell transfer. BALB/cJ and C3H mice were 'poor responders' in that FLD-3 cells grew well in their spleens, while mice of other strains were 'good responders', resisting the growth of FLD-3 cells. No H-2 or Fv genetic locus was associated with resistance. Athymic nude mice and mice depleted of marrow tissue by 89Sr or estradiol resisted FLD-3 cells, indicating that the effectors were thymus- and marrow-independent. Silica, carrageenan and Propionibacterium acnes organisms all altered resistance, suggesting a function of macrophages. Neither interferon nor anti-interferon serum treatment altered resistance. Anti-asialo GM1 serum inhibited resistance to FLD-3 cells in vivo and inhibited natural cytotoxic (NC) activity against FLD-3 cells in vitro. NC (FLD-3) activity was greatly decreased in spleens 3 days after irradiation, in contrast with NK (YAC-1) and NC(WEHI-164.1) activities. Moreover, a 3-day delay in infusion of FLD-3 cells 'synergized' with silica in weakening genetic resistance in vivo. Thus, natural immunity to FLD-3 cells in vivo differs from that of genetic resistance to normal bone marrow cell allografts, and the lysis of FLD-3 cells in vitro seems to be mediated by cells which do not easily fit into the definition of natural killer (NK) or natural cytotoxic (NC) cells.  相似文献   
109.
110.
Formalin-fixed sections of rat intestine were treated in a solution of 0.5% periodic acid in 50% aqueous phosphoric acid for the concurrent demonstration of 1,2-glycols and DNA. The effects of varying the concentration of reagents, time of exposure and temperature on the results showed that, at 28°C, good reactions were obtained in 10-15 min when the concentration of the phosphoric was between 40 and 60% and that of the periodic acid between 0.05 and 0.50%.  相似文献   
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