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21.
The prefrontal (PFC) and orbitofrontal cortex (OFC) appear to be associated with both executive functions and olfaction. However, there is little data relating olfactory processing and executive functions in humans. The present study aimed at exploring the role of olfaction on executive functioning, making a distinction between primary and more cognitive aspects of olfaction. Three executive tasks of similar difficulty were used. One was used to assess hot executive functions (Iowa Gambling Task-IGT), and two as a measure of cold executive functioning (Stroop Colour and Word Test-SCWT and Wisconsin Card Sorting Test-WCST). Sixty two healthy participants were included: 31 with normosmia and 31 with hyposmia. Olfactory abilities were assessed using the ‘‘Sniffin’ Sticks’’ test and the olfactory threshold, odour discrimination and odour identification measures were obtained. All participants were female, aged between 18 and 60. Results showed that participants with hyposmia displayed worse performance in decision making (IGT; Cohen’s-d = 0.91) and cognitive flexibility (WCST; Cohen’s-d between 0.54 and 0.68) compared to those with normosmia. Multiple regression adjusted by the covariates participants’ age and education level showed a positive association between odour identification and the cognitive inhibition response (SCWT-interference; Beta = 0.29; p = .034). The odour discrimination capacity was not a predictor of the cognitive executive performance. Our results suggest that both hot and cold executive functions seem to be associated with higher-order olfactory functioning in humans. These results robustly support the hypothesis that olfaction and executive measures have a common neural substrate in PFC and OFC, and suggest that olfaction might be a reliable cognitive marker in psychiatric and neurologic disorders.  相似文献   
22.
The restoration of body composition (BC) parameters is considered to be one of the most important goals in the treatment of patients with anorexia nervosa (AN). However, little is known about differences between AN diagnostic subtypes [restricting (AN-R) and binge/purging (AN-BP)] and weekly changes in BC during refeeding treatment. Therefore, the main objectives of our study were twofold: 1) to assess the changes in BC throughout nutritional treatment in an AN sample and 2) to analyze predictors of BC changes during treatment, as well as predictors of treatment outcome. The whole sample comprised 261 participants [118 adult females with AN (70 AN-R vs. 48 AN-BP), and 143 healthy controls]. BC was measured weekly during 15 weeks of day-hospital treatment using bioelectrical impedance analysis (BIA). Assessment measures also included the Eating Disorders Inventory-2, as well as a number of other clinical indices. Overall, the results showed that AN-R and AN-BP patients statistically differed in all BC measures at admission. However, no significant time×group interaction was found for almost all BC parameters. Significant time×group interactions were only found for basal metabolic rate (p = .041) and body mass index (BMI) (p = .035). Multiple regression models showed that the best predictors of pre-post changes in BC parameters (namely fat-free mass, muscular mass, total body water and BMI) were the baseline values of BC parameters. Stepwise predictive logistic regressions showed that only BMI and age were significantly associated with outcome, but not with the percentage of body fat. In conclusion, these data suggest that although AN patients tended to restore all BC parameters during nutritional treatment, only AN-BP patients obtained the same fat mass values as healthy controls. Put succinctly, the best predictors of changes in BC were baseline BC values, which did not, however, seem to influence treatment outcome.  相似文献   
23.
There is a need to know whether callous-unemotional (CU) traits identify a more severe group of oppositional defiant children (ODD). The aim of this study is to ascertain cross-sectionally and longitudinally the specific contribution of CU levels and the presence of ODD in the psychological state of preschool children from the general population. A total of 622 children were assessed longitudinally at ages 3 and 5 with a semi-structured diagnostic interview and questionnaires filled out by parents and teachers. In multivariate models simultaneously including ODD diagnosis and CU levels, controlling by socioeconomic status, ethnicity, sex, severity of conduct disorder symptoms and other comorbidity, high CU scores were related to higher levels of aggression, withdrawn, externalizing and global symptomatology, functional impairment and higher probability of comorbid disorders and use of services. The contribution of CU traits on children’s psychological state was not moderated by the presence/absence of ODD. Stability for CU traits and number of ODD-symptoms between ages 3 and 5 was statistically significant but moderate-low (intra-class correlation under .40). Assessment and identification of CU traits from preschool might help to identify a subset of children who could have socialization problems, not only among those with ODD but also among those without a diagnosis of conduct problems.  相似文献   
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Several studies have shown the importance of recent events in the configuration of the genetic landscape of a specific territory. In this context, due to the phenomena of repopulation and demographic fluctuations that took place in recent centuries, the Iberian Northern plateau is a very interesting case study. The main aim of this work is to check if recent population movements together with existing boundaries (geographical and administrative) have influenced the current genetic composition of the area. To accomplish this general purpose, mitochondrial DNA variations of 214 individuals from a population located in the Western region of the Iberian Northern plateau (the province of Zamora) were analyzed. Results showed a typical Western European mitochondrial DNA haplogroup composition. However, unexpected high frequencies of U5, HV0, and L haplogroups were found in some regions. The analyses of microdifferentiation showed that there are differences between regions, but no geographic substructure organization can be noticed. It can be stated that the differences observed in the genetic pool of the sampled area at regional level results from the mixture of different populations carrying new lineages into this area at different points in history. Am J Phys Anthropol 142:531–539, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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Duchenne muscular dystrophy (DMD) is a fatal and incurable muscle degenerative disorder. We identify a function of the protease urokinase plasminogen activator (uPA) in mdx mice, a mouse model of DMD. The expression of uPA is induced in mdx dystrophic muscle, and the genetic loss of uPA in mdx mice exacerbated muscle dystrophy and reduced muscular function. Bone marrow (BM) transplantation experiments revealed a critical function for BM-derived uPA in mdx muscle repair via three mechanisms: (1) by promoting the infiltration of BM-derived inflammatory cells; (2) by preventing the excessive deposition of fibrin; and (3) by promoting myoblast migration. Interestingly, genetic loss of the uPA receptor in mdx mice did not exacerbate muscular dystrophy in mdx mice, suggesting that uPA exerts its effects independently of its receptor. These findings underscore the importance of uPA in muscular dystrophy.  相似文献   
28.
The alcohol dehydrogenase class 3 enzyme (ADH3) is the presumed ancestral form of the medium-chain dehydrogenase-reductase ADH family. This enzyme has been involved in formaldehyde and nitric oxide metabolism of a variety of deuterostomes and ecdysozoan protostomes. We have now characterized the structure and expression of the Adh3 gene in the lophotrochozoan Schmidtea mediterranea, a freshwater planarian. The planarian gene expands over 8.7 kb and is organized into 7 exons. The 1340 bp long Adh3cDNA contains a 1137 bp open reading frame corresponding to a deduced protein of 379 amino acids. The protein sequence is consistent with that expected for a typical class III enzyme. Twenty out of the twenty-two amino acid positions associated with enzymatic roles are strictly preserved, which suggests that the enzymatic capabilities have been conserved. In situ hybridization experiments show that Adh3 is expressed along the intestine of S. mediterranea specimens. This is consistent with the pattern observed in invertebrates and in contrast with the widespread expression of vertebrate Adh3. The comparative study across bilateria, which now includes a lophotrochozoan representative, further supports the idea that the urbilaterian Adh3 ancestor showed an intron-rich architecture and tissue-specific expression, and strengthens the view that widespread expression of Adh3 was a vertebrate innovation.  相似文献   
29.
Information on localization of Al in tea leaf tissues is required in order to better understand Al tolerance mechanism in this Al-accumulating plant species. Here, we have used low-energy X-ray fluorescence spectro-microscopy (LEXRF) to study localization of Al and other low Z-elements, namely C, O, Mg, Si and P, in fully developed leaves of the tea plant [Camellia sinensis (L.) O. Kuntze]. Plants were grown from seeds for 3?months in a hydroponic solution, and then exposed to 200?μM AlCl3 for 2?weeks. Epidermal-mesophyll and xylem phloem regions of 20?μm thick cryo-fixed freeze-dried tea-leaf cross-sections were raster scanned with 1.7 and 2.2?keV excitation energies to reach the Al–K and P–K absorption edges. Al was mainly localized in the cell walls of the leaf epidermal cells, while almost no Al signal was obtained from the leaf symplast. The results suggest that the retention of Al in epidermal leaf apoplast represent the main tolerance mechanism to Al in tea plants. In addition LEXRF proved to be a powerful tool for localization of Al in plant tissues, which can help in our understanding of the processes of Al uptake, transport and tolerance in plants.  相似文献   
30.
Roscovitine, a potent inhibitor of M-phase promoting factor kinase activity, was used to maintain calf oocytes at the germinal vesicle stage for a 24h culture period. Cumulus-oocyte complexes were first prematured for 24h in the presence of different levels of roscovitine (12.5, 25, 50 and 100 microM). Roscovitine was shown to block germinal vesicle breakdown in calf oocytes in a concentration dependent manner. Significantly greater inhibitory effect was observed at 50 and 100 microM with 64.6% and 63.2% oocytes being blocked in the germinal vesicle stage when compared to the control (0.0%) and the 12.5 microM (2.9%) and 25 microM (18.8%) groups. However, this inhibitory effect of roscovitine was fully reversible since a substantial number of the oocytes resumed meiosis and reached the metaphase II stage after a further 24h of culture in a permissive medium. Cleavage rates and blastocyst yields were not significantly different for oocytes cultured under 50 microM roscovitine inhibition compared to oocytes not subjected to prematuration culture (rates of 76.7% cleavage and 8.7% blastocysts for control oocytes compared to 69.8% and 6.3%, respectively, for oocytes pretreated with 50 microM roscovitine). The morphology of the meiotic spindle was typical of metaphase II in 75.8% and 82.1% of the oocytes reaching the metaphase II stage after pretreatment with 50 microM roscovitine compared to control, respectively. A normal distribution of actin filaments was observed in 97.0% and 98.2% of oocytes exposed to 50 microM roscovitine compared to control, respectively. These results demonstrate the feasibility of maintaining calf oocytes in artificial meiotic arrest without compromising their subsequent developmental competence.  相似文献   
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