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Objective

Active anxiety disorders have lasting detrimental effects on pregnant mothers and their offspring but it is unknown if historical, non-active, maternal anxiety disorders have similar effects. Anxiety-related conditions, such as reduced autonomic cardiac control, indicated by reduced heart rate variability (HRV) could persist despite disorder resolution, with long-term health implications for mothers and children. The objective in this study is to test the hypotheses that pregnant mothers with a history of, but not current anxiety and their children have low HRV, predicting anxiety-like offspring temperaments.

Methods

The participants in this case-control study consist of 56 women during their first trimester and their offspring (15 male, 29 female). Women had a history of an anxiety disorder (n=22) or no psychopathology (n=34) determined using the Mini-International Neuropsychiatric Interview. The main outcome measures were indices of autonomic cardiac control including root mean square of successive differences (RMSSD) and high frequency (HF) variability. Children’s fearfulness was also assessed using the Laboratory Temperament Assessment Battery (Lab-TAB)-Locomotor Version.

Results

HRV was lower in women and children in the past anxiety group compared to controls. HRV measures for mothers and children were positively correlated in the anxiety group only. In all children, low HRV measures at 2-4 months were associated with a higher chance of fearful behavior at 9-10 months.

Conclusions

Pregnant women with previous but not current anxiety and their children have low HRV. Children with low HRV tend to show more fearfulness. These findings have implications for identifying children at risk of anxiety disorders and point to possible underlying mechanisms of child psychopathology.  相似文献   
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Recent results have suggested a role for prolactin (PRL) as a regeneration factor in the liver. In order to investigate the involvement of prolactin in the pathogenesis of liver cirrhosis, we studied the expression of the prolactin receptor (PRLR) and PRL during the development of cirrhosis in an animal model. 30 male rats were exposed to CCl4 by inhalation. Phenobarbitone was added to the drinking water to accelerate the formation of toxic metabolites by enzyme induction. Two control groups of 30 animals each were treated with phenobarbitone only or received no treatment. 10 animals of each group were sacrificed 35, 55, and 70 days after initiation of treatment. Liver tissue was subjected to histological examination, which demonstrated fibrosis of different grades and cirrhosis in the CCl4-treated rats. Expression of PRLR mRNA was investigated by mRNA extraction, RT-PCR and computer-supported densitometric evaluation. Compared to control liver, PRLR mRNA was expressed at a higher level in fibrotic and cirrhotic liver specimens. In normal tissue, immunohistochemical staining showed a high concentration of PRLR around the central vein and in the epithelium of the bile ducts. This pattern of distribution was lost in fibrosis and cirrhosis. An accumulation of PRLR was demonstrated within the damaged cells. Neither PRL nor PRL mRNA was detectable in normal, fibrotic, or cirrhotic liver. We conclude that PRLR is distributed in normal rat liver in a typical pattern which is lost with increasing fibrosis. PRL is not produced by rat liver, indicating that PRL does not act through autocrine or paracrine mechanisms.  相似文献   
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A duplication of chromosome 15q24-q26 (DUP25) has been reported to be associated with anxiety disorders. We tested for the presence of DUP25 in a sample of 50 patients with panic disorder and 50 controls using a quantitative real-time PCR approach. Contrary to the original finding, our results were compatible with the absence of DUP25, and no significant difference could be detected between patients and controls (P=1.0). Thus, our study does not support the hypothesis of an involvement of DUP25 in panic disorder.  相似文献   
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The role of phenotypical plasticity in ecological speciation and the evolution of sexual isolation remains largely unknown. We investigated whether or not divergent host plant use in an herbivorous insect causes assortative mating by phenotypically altering traits involved in mate recognition. We found that males of the mustard leaf beetle Phaedon cochleariae preferred to mate with females that were reared on the same plant species to females provided with a different plant species, based on divergent cuticular hydrocarbon profiles that serve as contact pheromones. The cuticular hydrocarbon phenotypes of the beetles were host plant specific and changed within 2 weeks after a shift to a novel host plant species. We suggest that plant-induced phenotypic divergence in mate recognition cues may act as an early barrier to gene flow between herbivorous insect populations on alternative host species, preceding genetic divergence and thus, promoting ecological speciation.  相似文献   
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Populations of the introduced Heracleum mantegazzianum consist of dense central stands, which gradually give way to open stands towards the margins. To analyse whether open stands are due to unsuitable conditions or represent the invading front for further spread, we studied life-cycle, population dynamics, stand structure and soil conditions of open and dense stands over two transition periods. Populations decreased during the first interval but increased after the extremely dry and warm summer of 2003 during the second interval. Open stands had shorter generation times, lower height, smaller proportions of small individuals and were less in equilibrium with the environment than dense stands. In open stands, growth to higher stages was most important, while in dense stands delayed development (self-loops) had a strong effect on population growth; stasis and fecundity contributed most to the difference in λ between stand types. By petiole extension H. mantegazzianum may raise its leaves just above the resident vegetation. Therefore, younger stages develop faster in open stands, whereas strong competition by conspecific adults leads to longer generation times and a higher proportion of small individuals in dense stands. Disturbance due to extreme climatic conditions in summer 2003 equalised population dynamics of both stand types. Life-cycle variation between stand types makes it difficult to infer simple management rules. However, our data suggest that small and/or open stands of H. mantegazzianum may eventually serve as initials for further spread after land-use changes, whereas dense stands are stable and may represent sources of propagules.  相似文献   
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Hydrobiologia - The crustacean genus Daphnia holds a key position in aquatic ecosystems rendering it an important model organism in environmental research. Its enormous sensitivity to environmental...  相似文献   
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Imagination pushes humanity well beyond its natural biological capacities. An approach of co-evolution, between molecular biology and behaviour, is thus required to explain these combined processes. Technological performances define spiritual conquests and formulas whose sole function is cultural. Humanity operates according to intentional social modes defined by the group, but these immediately become conditions for their own evolution. These choices are the motor for the history of humanity, and thus humanity can itself choose its own path. Anatomic modernisation is only a distant reflection of bipedalism, but freeing the hands leads to the development of abstract thought. The relationship between anatomy and awareness allows infinite variations in the harmonious adaptation to nature, animals and other societies. In Europe, humanity arrived in abrupt bursts because it was the result of external evolution, continuous and distant, dispersed across Asia. By its unceasing audacity, humanity combats biological determinism, imposing “moral” rules, or imperatives. The balance between biology and culture is reflected in the rules for sharing food: the biological life itself is coded by social sharing. These systems take on ternary values as soon as they include animal behaviours. Built shelters integrate societies with the cosmos because they delimit cultural spaces within natural chaos. Mastery of cognitive mechanisms gives humanity an entirely new responsibility, that of being able to define its destiny. Our united disciplines are transformed into ethical requirements.  相似文献   
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