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101.
This paper reviews the research evidence concerning the intergenerational transmission of trauma effects and the possible role of epigenetic mechanisms in this transmission. Two broad categories of epigenetically mediated effects are highlighted. The first involves developmentally programmed effects. These can result from the influence of the offspring's early environmental exposures, including postnatal maternal care as well as in utero exposure reflecting maternal stress during pregnancy. The second includes epigenetic changes associated with a preconception trauma in parents that may affect the germline, and impact fetoplacental interactions. Several factors, such as sex‐specific epigenetic effects following trauma exposure and parental developmental stage at the time of exposure, explain different effects of maternal and paternal trauma. The most compelling work to date has been done in animal models, where the opportunity for controlled designs enables clear interpretations of transmissible effects. Given the paucity of human studies and the methodological challenges in conducting such studies, it is not possible to attribute intergenerational effects in humans to a single set of biological or other determinants at this time. Elucidating the role of epigenetic mechanisms in intergenerational effects through prospective, multi‐generational studies may ultimately yield a cogent understanding of how individual, cultural and societal experiences permeate our biology.  相似文献   
102.
Although previous paleopathological studies have used disturbances in enamel formation as indicators of childhood stress, the full potential of this technique has not been realized. This paper presents a test case which demonstrates that the frequency of disturbed enamel formation (i.e., Wilson bands) is associated with other stress indicators (i.e., probability of dying and infectious lesions) in three prehistoric skeletal samples representing the Middle Woodland (10.3%), Mississippian Acculturated Late Woodland (21.4%), and the Middle Mississippian (40.0%). Additionally, the mean ages at death of individuals with at least one Wilson band are lower than those without bands.These results suggest that Wilson bands are an indicator of the relative proportion of individuals who are high susceptibles in prehistoric populations. The data also corroborate the hypothesis that the adoption of maize agriculture in the prehistoric American Midwest is associated with increased stress.  相似文献   
103.
为探究草莓花器官对高温、低温、盐胁迫的响应特征,该研究以草莓品种‘甜查理’为试材,设置0℃、4℃、25℃(CK)、37℃、200 mmol/L NaCl、400 mmol/L NaCl等逆境胁迫处理,考察草莓花外观形态、生长发育状态、花器官抗氧化酶活性,以及3个草莓花器官分生组织特异性基因、12个成花途径基因、3个抗氧化酶基因、6个抗逆基因的表达等。结果显示:(1)0℃、4℃、37℃、200 mmol/L NaCl、400 mmol/L NaCl溶液处理均抑制了草莓花的开放,0℃低温显著抑制草莓花器官的开放,并对草莓的花器官造成伤害。(2)当草莓植株受到高温、低温、盐胁迫时,其花器官内抗氧化酶SOD、POD、CAT活性及MDA含量均得到提高,其相关抗氧化酶基因的表达水平也相应提高。(3)0℃、4℃、37℃以及200 mmol/L NaCl、400 mmol/L NaCl溶液处理均显著降低了草莓花器官FaAP1、FaLFY、FaFD、FaSOC1等成花基因的表达量;0℃低温诱导了FaICE、FaRD29A、FaCOR、FaAFP等4个抗寒基因的表达水平;200 mmol/L NaCl、400 mmol/L NaCl的盐胁迫显著提高了FaP5CS基因的表达量。研究表明,0℃、4℃、37℃、200 mmol/L NaCl、400 mmol/L NaCl溶液处理不同程度抑制了草莓的开花进程,对草莓花器官造成伤害;不同逆境胁迫处理显著提高了草莓花器官SOD、POD、CAT活性以及MDA含量,相应的抗氧化酶基因表达得到上调,同时显著降低了草莓成花途径相关基因表达,增强了相关抗逆基因的表达水平。  相似文献   
104.
Epidemiological studies have indicated no association between diagnostic ultrasound exposure during pregnancy and childhood malignancies. Diagnostic ultrasound imaging does not seem to influence birth weight, whereas frequent Doppler ultrasound was associated with reduced birth weight in one study. Most experts do not believe that ultrasound exposure during pregnancy is associated with reduced birth weight. There are no confirmed statistically significant associations between ultrasound and dyslexia and neurological development during childhood. However, two randomised controlled trials and two cohort studies have been unable to rule out a possible association between ultrasound and left-handedness among males.  相似文献   
105.
Birth weight has been shown to be associated with obesity and metabolic diseases in adulthood, however, the genetic contribution is still controversial. The objective of this analysis is to explore the genetic contribution to the relationship between birth weight and later risk for obesity and metabolic diseases in Hispanic children. Subjects were 1,030 Hispanic children in the Viva La Familia Study. Phenotypes included body size, body composition, blood pressure, fasting glucose, insulin, lipids, and liver enzymes. Birth weights were obtained from Texas birth certificates. Quantitative genetic analyses were conducted using SOLAR software. Birth weight was highly heritable, as were all other phenotypes. Phenotypically, birth weight was positively correlated to childhood body size parameters. Decomposition of these phenotypic correlations into genetic and environmental components revealed significant genetic correlations, ranging from 0.30 to 0.59. Negative genetic correlations were seen between birth weight and lipids. The genome scan of birth weight mapped to a region near marker D10S537 (LOD = 2.6). The bivariate genome-wide scan of birth weight and childhood weight or total cholesterol, improved the LOD score to 3.09 and 2.85, respectively. Chromosome 10q22 harbors genes influencing both birth weight and childhood body size and cardiovascular disease risk in Hispanic children.  相似文献   
106.
Jonah Steinberg 《Ethnos》2015,80(2):248-271
ABSTRACT

How does the status of ‘street children’ in life inflect the narrative representation of their deaths? Street-dwelling children's interactions with death in North India reveal much about how their identities are produced in public domains. In this paper, I examine several instances of ‘homeless child’ death to illuminate the place of such subjects in society and urban space, and to interrogate the degree to which they can be rendered ‘recognizable’ or ‘grievable’, in Butler's (2010) terminology. In particular, I explore the presence or absence of kin in the ways that child death is narrated. I also explore the related question of how living ‘vagabond (aawara) children’ situate their status in narratives of death and loss. I conclude with discussions of how children negotiate their orientations towards death through ghost narratives, and of the space-, economy- and age-bound assignment of pollutive tasks once reserved for low castes to street-dwelling children.  相似文献   
107.
Cognitive impairment in schizophrenia involves a broad array of nonsocial and social cognitive domains. It is a core feature of the illness, and one with substantial implications for treatment and prognosis. Our understanding of the causes, consequences and interventions for cognitive impairment in schizophrenia has grown substantially in recent years. Here we review a range of topics, including: a) the types of nonsocial cognitive, social cognitive, and perceptual deficits in schizophrenia; b) how deficits in schizophrenia are similar or different from those in other disorders; c) cognitive impairments in the prodromal period and over the lifespan in schizophrenia; d) neuroimaging of the neural substrates of nonsocial and social cognition, and e) relationships of nonsocial and social cognition to functional outcome. The paper also reviews the considerable efforts that have been directed to improve cognitive impairments in schizophrenia through novel psychopharmacology, cognitive remediation, social cognitive training, and alternative approaches. In the final section, we consider areas that are emerging and have the potential to provide future insights, including the interface of motivation and cognition, the influence of childhood adversity, metacognition, the role of neuroinflammation, computational modelling, the application of remote digital technology, and novel methods to evaluate brain network organization. The study of cognitive impairment has provided a way to approach, examine and comprehend a wide range of features of schizophrenia, and it may ultimately affect how we define and diagnose this complex disorder.  相似文献   
108.
Understanding the origins of political authoritarianism is of key importance for modern democracies. Recent works in evolutionary psychology suggest that human cognitive preferences may be the output of a biological response to early stressful environments. In this paper, we hypothesized that people's leader preferences are partly driven by early signals of harshness. We experimentally elicited children's (Study 1) and adults' (Study 2) political preferences using faces controlled for dominance and trustworthiness and showed that early childhood harshness has an enduring effect on adult political attitudes. Importantly, this effect was further confirmed using self-reported extreme authoritarianism (Study 2) and by the analysis of the large database of the European Value Survey (Study 3). We discuss the potential political implications of this early calibration of leader preferences.  相似文献   
109.
110.
以16个小麦品种的种子为材料,通过标准发芽、逆境发芽和田间出苗试验,测定不同基因型小麦品种的种子活力,以不同发芽条件下种子活力指数的抗逆指数和田间出苗率作为衡量抗逆性的指标,利用主成分分析、聚类分析对种子活力进行综合评价.结果表明: 干旱胁迫、人工老化和冷浸胁迫3种逆境对种子活力都有一定的影响.人工老化抗逆指数和冷浸胁迫抗逆指数与田间出苗率呈显著正相关,干旱胁迫抗逆指数与田间出苗率的相关性不显著.通过主成分分析和聚类分析将16个小麦品种划分为3类、豫农949、豫麦49-198、鲁原502、郑育麦9987、石麦21、山农23号、石新828为高活力品种;许农5号、豫农982、唐麦8号、济麦20、济麦22、济南17号、山农20为中活力品种;长4738和轮选061属低活力品种.  相似文献   
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