首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   289篇
  免费   7篇
  296篇
  2024年   1篇
  2023年   1篇
  2022年   2篇
  2021年   3篇
  2020年   7篇
  2019年   8篇
  2018年   8篇
  2017年   11篇
  2016年   13篇
  2015年   4篇
  2014年   7篇
  2013年   50篇
  2012年   18篇
  2011年   12篇
  2010年   5篇
  2009年   1篇
  2008年   19篇
  2007年   6篇
  2006年   10篇
  2005年   11篇
  2004年   10篇
  2003年   5篇
  2002年   10篇
  2001年   2篇
  2000年   2篇
  1999年   3篇
  1998年   6篇
  1997年   4篇
  1996年   2篇
  1995年   2篇
  1994年   4篇
  1993年   2篇
  1992年   6篇
  1991年   3篇
  1990年   3篇
  1989年   4篇
  1988年   5篇
  1987年   5篇
  1986年   5篇
  1985年   1篇
  1984年   1篇
  1983年   2篇
  1980年   2篇
  1978年   1篇
  1977年   2篇
  1975年   2篇
  1974年   1篇
  1970年   1篇
  1939年   3篇
排序方式: 共有296条查询结果,搜索用时 15 毫秒
241.
242.
Hypertension is a risk factor for neurodegenerative disorders involving inflammation and inflammatory cytokine-producing brain cells (microglia and astrocytes) in the hippocampus and medial prefrontal cortex (mPFC). Here we investigated the effect of slow-pressor angiotensin II (AngII) on gliosis in the hippocampus and mPFC of young adult (2-mo-old) male and female mice. In males, AngII induced hypertension, and this resulted in an increase in the density of the astrocyte marker glial fibrillary acidic protein (GFAP) in the subgranular hilus and a decrease in the density of the microglial marker ionized calcium binding adapter molecule (Iba-1) in the CA1 region. Females infused with AngII did not show hypertension but, significantly, showed alterations in hippocampal glial activation. Compared with vehicle, AngII-infused female mice had an increased density of Iba-1 in the dentate gyrus and CA2/3a region. Like males, females infused with AngII exhibited decreased Iba-1 in the CA1 region. Neither male nor female mice showed differences in GFAP or Iba-1 in the mPFC following AngII infusion. These results demonstrate that the hippocampus is particularly vulnerable to AngII in young adulthood. Differences in gonadal hormones or the sensitivity to AngII hypertension may account for divergences in GFAP and Iba-1 in males and females.

Hypertension is a significant risk factor for neurological disorders such as Alzheimer''s disease (AD) that are associated with neurodegeneration and cognitive decline (Daugherty 2021). Hypertension can develop during the life span yet is often studied at middle and late life. There is emerging evidence that hypertension is becoming more common in late adolescence and early adulthood (Azegami et al. 2021; Hamrahian and Falkner 2022). In addition, there is increasing awareness that the duration of hypertension can impact the onset of neural degeneration (Schaare et al. 2019; Yang et al. 2021) and cognitive dysfunction (Yaffe et al. 2014, 2021; Mahinrad et al. 2020; Zhou et al. 2022). Although the age of onset of hypertension may influence the trajectory of degenerative disease in later life, the effect of hypertension on brain health in young adult subjects is relatively underinvestigated.Hippocampal and medial prefrontal cortical pathology are commonly present in neurodegenerative diseases like AD (Belonwu et al. 2021). Structurally and functionally, both the hippocampus and mPFC also are compromised during hypertension (Raz et al. 2007; Gonzalez et al. 2015; Bu et al. 2018). In the hippocampus, hypertension is known to disrupt cerebrovascular function, promote inflammatory processes, and contribute to neuronal impairment and cognitive decline (Iulita et al. 2018). Although less studied than the hippocampus, the PFC is also compromised by hypertension (Raz et al. 2007; Bu et al. 2018; Wang et al. 2020).Microglia, the resident macrophages in the brain, have been implicated in inflammatory states, cognitive function (Cornell et al. 2022), and the brain''s response to hypertension (Calvillo et al. 2019; Li et al. 2020). An increase in the density of ionized calcium binding adapter molecule (Iba-1), a protein constitutively expressed in microglia and up-regulated when microglia enter an activated stage (Imai et al. 1996; Sasaki et al. 2001), is commonly reported in models of cognitive and neurodegenerative disorders (Prinz et al. 2021).In addition to microglia, astrocytes also have been implicated in the emergence of hippocampal and cortical dysfunction. Astrocytes play critical roles in blood–brain barrier (BBB) formation; brain metabolic, ion, and water homeostasis; neurotransmitter recycling; synapse formation; and neuroimmune signaling (Matias et al. 2019). In the context of insult, pathogen infection, or neurological disease, astrocytes undergo functionally complex reactive responses (Chiu et al. 2014; Giovannoni and Quintana 2020) that are associated with an increase in glial fibrillary acidic protein (GFAP) gene and protein expression (Crespo-Castrillo et al. 2020; Sofroniew 2020).To better understand the consequences of elevated blood pressure on the young adult brain, we conducted an exploratory investigation of the impact of hypertension on the expression of microglia and astrocyte markers—Iba-1 and GFAP, respectively—in the hippocampus and mPFC of male mice. Mice were exposed to angiotensin II (AngII) using the “slow-pressor” model (Dickinson and Lawrence 1963), which in males mimics the gradual rise in blood pressure and increase in sympathetic activation (Grassi and Ram 2016; Lerman et al. 2019) characteristic of essential hypertension (Lerman et al. 2019). Significantly, there is an important sex dimorphism in the risk for hypertension. Compared with men, women are protected from hypertension before middle age but become increasingly affected as they reach perimenopause, and intact young female rodents show a reduced sensitivity to AngII hypertension (Van Kempen et al. 2016). Similarly, there are sex differences in the incidence, progression, and severity of hypertension-associated neurodegenerative disease (Lopez-Lee et al. 2021). Furthermore, sex differences in glial function have also been documented within the context of neurodegenerative diseases (Kodama and Gan 2019; Biechele et al. 2020). Given this evidence, the effect of AngII on hippocampal and medial prefrontal cortical glial markers also was investigated in young intact female mice.  相似文献   
243.
A default mode network of brain regions is known to demonstrate coordinated activity during the resting state. While the default mode network is well characterized in adults, few investigations have focused upon its development. We scanned 9-13-year-old children with diffusion tensor imaging and resting-state functional magnetic resonance imaging. We identified resting-state networks using Independent Component Analysis and tested whether the functional connectivity between the medial prefrontal cortex (mPFC) and posterior cingulate cortex (PCC) depends upon the maturation of the underlying cingulum white matter tract. To determine the generalizability of this relationship, we also tested whether functional connectivity depends on white matter maturity between bilateral lateral prefrontal cortex (lateral PFC) within the executive control network. We found a positive relationship between mPFC-PCC connectivity and fractional anisotropy of the cingulum bundle; this positive relationship was moderated by the age of the subjects such that it was stronger in older children. By contrast, no such structure-function relationship emerged between right and left lateral PFC. However, functional and structural connectivity of this tract related positively with cognitive speed, fluency, and set-switching neuropsychological measures.  相似文献   
244.
We examined the persistence of psychiatric disorders at approximately 18 and 30 months after a hurricane among a random sample of the child and adolescent population (4–17 years) of Puerto Rico. Data were obtained from caretaker-child dyads (N = 1,886) through in person interviews with primary caretakers (all children) and youth (11–17 years) using the Diagnostic Interview Schedule for Children IV in Spanish. Logistic regressions, controlling for sociodemographic variables, were used to study the relation between disaster exposure and internalizing, externalizing, or any disorder. Children’s disaster-related distress manifested as internalizing disorders, rather than as externalizing disorders at 18 months post-disaster. At 30 months, there was no longer a significant difference in rates of disorder between hurricane-exposed and non-exposed youth. Results were similar across age ranges. Rates of specific internalizing disorders between exposed and unexposed children are provided. Research and clinical implications are discussed.  相似文献   
245.
The planarian flatworm is one of the simplest animals to develop two eyecups that enable them to detect the presence and direction of light, which they typically avoid. In this study we assessed responses of planaria to different intensities of light. We found that they exhibited a graded, sigmoidal, photonegative response to light intensity. A two-octave increase in luminance (on the upward slope of the sigmoid) corresponded to a 9% increase in the speed planaria travelled to avoid light.  相似文献   
246.
Three experiments with university students (Ns = 40, 36, and 36) who were non‐math majors explicitly examined whether repetition in performing ‘students‐and‐professors’‐type algebra word problems, which have been shown in the past to be vexingly difficult even for more advanced students, would spontaneously lead to higher rates of correct answers. Word order and situation model specificity were also examined to determine their effects on the rate of improvement. The strongest predictor of students producing correct equations (i.e., not producing the typical ‘reversal error’) was practice: In all experiments, participants spontaneously improved in equation accuracy almost to ceiling levels as they progressed, despite receiving no feedback. Tentative support is provided for the pedagogical value of repetition in solving problems, along with varying the wording of the problems. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
247.
Research suggests that difficulties in emotion regulation are an important correlate of nonsuicidal self-injury (NSSI) in adults. Research examining this link in adolescents is limited by the lack of comprehensive instruments to assess difficulties in emotion regulation. Against this background, the aims of the current study were to (a) confirm the six-factor structure of the Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, Journal of Psychopathology and Behavioral Assessment, 23(4), 253?C263, 2004) in a sample of adolescent inpatients (N?=?218); (b) explore the relation between different aspects of emotion dysregulation and lifetime NSSI while controlling for psychopathology and sex; and (c) assess the clinical utility of the DERS in detecting lifetime NSSI status. Fit indices obtained through Confirmatory Factor Analysis indicated that the six-factor structure of the DERS fit the data adequately and that most items loaded strongly on their respective latent factor. All six latent factors were significantly correlated with each other, with the exception of lack of emotional awareness and difficulties engaging in goal-directed behavioral when distressed. Regression analyses revealed that only the limited access to emotion regulation strategies subscale accounted for a significant portion of the variance in NSSI when controlling for other aspects of emotion dysregulation, sex, and psychopathology. Receiver Operating Characteristic analysis indicated that the DERS limited access to emotion regulation strategies subscale score has moderate diagnostic accuracy in detecting the presence of NSSI. The optimal cut-off score was 21.5 when detecting NSSI among inpatient adolescents. Results provide further support for the relation between emotion regulation difficulties and NSSI. The DERS appears to be a useful measure of detecting NSSI in clinical samples of adolescents.  相似文献   
248.
The present study examined the association between forgiveness and marital satisfaction in relation to marital stability. It was a comparative study between first-married and remarried adults involving 787 respondents from the Flanders region in Belgium. The current study showed that, although in the overall forgiveness, there was no significant difference between the first-married and remarried, the first-married significantly differed in two subscales of Enright Forgiveness Inventory (EFI) from the remarried. A significant difference in the marital satisfaction was found between the first-married and remarried adults. The present study also reported a significant positive correlation between forgiveness and general-life adjustment.This study was carried out at the Institute for the Family and Sexuality Sciences, Katholieke Universiteit Leuven, as part of docotral research.  相似文献   
249.
This study examined the association between religiosity and marital satisfaction among first-married and remarried adults. Seven hundred and eighty-seven heterosexually married adults from the Flanders region in Belgium completed the Maudsley Marital Questionnaire (MMQ) and a four-item religiosity scale, measuring marital satisfaction and religiosity respectively. This study found the effect of gender and marital status statistically significant (p < .0001) on religiosity. For marital satisfaction, the effect of gender and marital status statistically significant only for MMQ-S (p < .0001) and MMQ-M (p < .0001) respectively. Religiosity had a significant positive correlation (r = .19, p < .0001) with sexual-adjustment problems (MMQ-S). The ultimate aim of this study was to inform marital and relational therapists the value of a possible association religiosity has on marital satisfaction.This study was conducted at the Institute for the Family and Sexuality Sciences, Katholieke Universiteit Leuven, as part of doctoral research.  相似文献   
250.
The universality versus cultural specificity of Mexican personality dimensions was investigated by examining: (a) the replicability of Mexican personality dimensions assessed by indigenous inventories; and (b) the extent to which Mexican dimensions are encompassed by the Five-Factor Model (FFM), one hypothesized universal model of personality structure. Mexican university students (N = 794) completed nine indigenous inventories and the Spanish version of the Revised NEO Personality Inventory. The FFM replicated well, although reliability was poor for a few facet scales. Reliability was acceptable for the indigenous Mexican scales. However, for most indigenous instruments, a cross-sample replication criterion suggested alternative structures of fewer, more replicable dimensions. Multiple regression and joint factor analyses revealed that most of the Mexican dimensions were well subsumed by the FFM. Thus, cultural differences did not involve clearly culture-specific dimensions, but more subtle differences in the salience or cultural flavor of particular traits.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号