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61.
Meaningful gestures enhance speech comprehensibility. However, their role during novel-word acquisition remains elusive. Here we investigate how meaningful versus meaningless gestures impact on novel-word learning and contrast these conditions to a purely verbal training. After training, neuronal processing of the novel words was assessed by blood-oxygen-level-dependent functional magnetic resonance imaging (BOLD-fMRI), disclosing that networks affording retrieval differ depending on the training condition. Over 3 days participants learned pseudowords for common objects (e.g., /klira/ -cap). For training they repeated the novel word while performing (i) an iconic, (ii) a grooming or (iii) no gesture. For the two conditions involving gestures, these were either actively repeated or passively observed during training. Behaviorally no substantial differences between the five different training conditions were found while fMRI disclosed differential networks affording implicit retrieval of the learned pseudowords depending on the training procedure. Most notably training with actively performed iconic gestures yielded larger activation in a semantic network comprising left inferior frontal (BA47) and inferior temporal gyri. Additionally hippocampal activation was stronger for all trained compared to unknown pseudowords of identical structure. The behavioral results challenge the generality of an ‘enactment-effect’ for single word learning. Imaging results, however, suggest that actively performed meaningful gestures lead to a deeper semantic encoding of novel words. The findings are discussed regarding their implications for theoretical accounts and for empirical approaches of gesture-based strategies in language (re)learning.  相似文献   
62.
In the human, visually evoked potentials (VEP) and cerebral oxygenation changes, as measured by near-infrared spectroscopy (NIRS), are assessed to elucidate the relation between electrophysiological and vascular responses to a checkerboard stimulus reversing at 3 Hz. Habituation of either response is analysed on two time scales. Within the 1-min stimulation period we find a decrease in P100N135-component amplitude, closely coupled to a decrease in the amplitude of the oxygenation parameters (concentration changes in oxygenated and deoxygenated haemoglobin, [oxy-Hb] and [deoxy-Hb]). The N75P100-component amplitude exhibits a different behaviour along the 1-min stimulation period. An initial increase is overridden by an overall decrease, the latter not reaching statistical significance. The analysis across the 13 successive stimulation blocks separated by resting periods of equal duration yields a trend for an decrease in the VEP-components' amplitude, not reflected in the vascular response. When calculating a ratio between the amplitude of the P100N135-component and the concentration changes in the haemoglobins a "coupling index" of a 0.2 microM decrease in [deoxy-Hb] and an increase of 0.6 microM in [oxy-Hb] is found per 1 microV increase in VEP-component amplitude. The ratio is the same irrespective of its assessment from the difference stimulation/ rest or from the habituation effect, i.e., the difference between the amplitudes at the beginning and towards the end of the stimulation period. Although supporting the notion that the coupling between neuronal activation and the vascular response exhibits linear aspects, our findings cannot be taken as a proof of such a linearity across all brain regions and activation types. On the contrary, tentatively calculating a coupling index for the data assessed in the visual system, we intend to stress the necessity to assess both neuronal and vascular response to allow for a comparison between different systems and conditions in whom neurovascular coupling is expected to be altered (Miller et al, 2001; Mechelli et al, 2001).  相似文献   
63.
When the demand for inpatient treatment in acute psychiatric crisis of adolescents rises, it is not always recommended to admit a patient to the hospital. The limited number of hospital beds forces medical professionals to use their resources cautiously. This leads to the need to activate the intrapersonal and intrafamilial resources. The motivation for change emerging out of a crisis is to be used for clarification of the indication of inpatient treatment and of the order of treatment, a patient (and/or his legal representative) gives to the hospital representatives. A clarification of the aims of a hospitalisation prior to the admission to the ward rises the efficacy of the invested time.  相似文献   
64.
Summary A method for the projection of EEG data on the brain surface is proposed. The EEG data are obtained during the performance of mentaltasks and represented as probability maps of power and coherencechanges with respect to the averaged EEG at rest. The morphological data are obtained from 3D reconstructions of the brain by means of serial slices provided by an MRI scanner. Before scanning the positions of the EEG electrodes were marked by dummy electrodes of plexiglass filled with a contrast medium. Changes of power are color-coded and entered at the respective electrode positions, changes of coherence between the respective positions. The applicability of this procedure in the fields of psychology, psychiatry and neurology is discussed.This work was partially supported by the Austrian Fonds zur Förderung der wissenschaftlichen Forschung, Projects P8189-MED and S49-MED.  相似文献   
65.
Suicidal ideation and aggression are common correlates of posttraumatic stress disorder (PTSD) among U.S. Iraq and Afghanistan war veterans. The existing literature has established a strong link between these factors, but a more nuanced understanding of how PTSD influences them is needed. The current study examined the direct and indirect relationships between PTSD symptom clusters and suicidal ideation in general aggression (without a specified target) regarding depression, alcohol misuse, and trait anger. Participants were 359 (92% male) U.S. Iraq/Afghanistan war veterans. Path analysis results suggested that the PTSD numbing cluster was directly (β = .28, p < .01) and indirectly (β = .17, p = .001) related through depression. The PTSD hyperarousal cluster was indirectly related to suicidal ideation through depression (β = .13, p < .001). The PTSD reexperiencing cluster was directly related to aggression (β = .17, p < .05), whereas the PTSD numbing and hyperarousal clusters were indirectly related to aggression through trait anger (β = .05, p < .05; β = .20, p < .001). These findings indicate that adjunct treatments aimed at stabilizing anger, depression, and alcohol misuse may help clinicians ameliorate the maladaptive patterns often observed in veterans. These results also point to specific manifestations of PTSD and co‐occurring conditions that may inform clinicians in their attempts to identify at risk veterans and facilitate preventative interventions.  相似文献   
66.
BACKGROUND: Excellent metabolic control before conception and during diabetic pregnancies is the aim in order to avoid malformations and perinatal morbidity. Since an inverse correlation between median blood glucose concentration (BG) and hypoglycemia as well as a high prevalence of nocturnal hypoglycemia have been described, we investigated the frequency of nocturnal hypoglycemia and the predictive value of bedtime blood glucose concentration for development of this condition in insulin treated diabetic patients. METHODS: During hospitalization, with no other changes in the patients' normal schedules, hourly blood samples were drawn from an iv-cannula from 22.00 h to 07.00 h for one night. BG (venous whole blood) and hemoglobin A1c were determined the following day. RESULTS: Fifty-three patients participated; subsequently ten were excluded due to discontinuation of blood sampling during the night, caused by either discomfort or cannula problems. Of the remaining 43 patients, 16 (37%) had at least one blood glucose <3.0 mmol/l. The duration of hypoglycemia was 2.4 (1-7) h with the highest prevalence at 05 h. Only one patient felt hypoglycemic during the night. Hemoglobin A1c was similar in patients with (7.1+/-1.2%, mean+/-s.d.) and without (6.8+/-0.8%) nocturnal hypoglycemia. Women with nocturnal hypoglycemia had significantly lower BG before bedtime compared to patients without hypoglycemia, 6.4+/-3.6 mmol/l vs. 7.9+/-2.4 mmol/l, p<0.05. The best predictive value for nocturnal hypoglycemia was a BG below 6.0 mmol/l at 23.00, which resulted in a risk of nocturnal hypoglycemia of 71%. Conversely, if the BG was > or =6.0 mmol/l, the chance of avoiding nocturnal hypoglycemia was 83%. CONCLUSION: Nocturnal hypoglycemia was seen with a prevalence of 37% during a night in the first trimester of pregnancy in insulin treated patients. Only one patient registered the hypoglycemia. Nocturnal hypoglycemia could be predicted in the majority of patients by measurements of BG before bedtime.  相似文献   
67.
68.
Towards a standard analysis for functional near-infrared imaging   总被引:1,自引:0,他引:1  
Functional near-infrared spectroscopy (fNIRS) allows the ability to monitor brain activation by measuring changes in the concentration of oxy- and deoxy-hemoglobin. Until now no standardized approach for fNIRS data analysis has been established, although this has to be regarded as a precondition for future application. Hence, we applied the well-established general linear model to optical imaging data. Further, fNIRS data were analyzed in the frequency domain. Two visual tasks were investigated with optical imaging: a checkerboard paradigm supposed to activate the primary and secondary visual cortex, and a paradigm consisting of moving colored stimuli (rotating 'L's) additionally involving the motion area V5. Analysis with the general linear model detected the activation focus in the primary and secondary visual cortex during the first paradigm. For the second paradigm, a second laterally localized activated brain region was found, most likely representing V5. Spatially resolved spectral analysis confirmed the results by showing maxima of power spectral density and coherence in the same respective brain regions. Moreover, it demonstrated a delay of the hemodynamic response in the motion area. In summary, the present study suggests that the general linear model and spatially resolved spectral analysis can be used as standard statistical approaches for optical imaging data, particularly because they are almost independent of the assumed differential path length factors.  相似文献   
69.
70.
Zusammenfassung Infolge eines Gerichtsentscheides über eine Oscillographie wird der rechtliche Wert dieser Untersuchungsmethoden beleuchtet, insbesondere werden die vielen Fehlermöglichkeiten aufgezeigt, die nur dann ein exaktes Bild zulassen, wenn der Untersucher größte Sorgfalt anwendet, die zeitraubend ist.Nach Fertigstellung der Arbeit ergeht am 19. 4. 1961 der Beschluß, daß das Sozialgericht die oben gestellte Zeitnorm für Oscillographie einschließlich Thermographie sowie mathematische Auswertung in vollem Umfange anerkennt. Es handelt sich dabei um eine endgültige Entscheidung nach § 15 Abs. 2 GEZS.  相似文献   
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