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71.
We evaluated a program for teaching two adolescents with autism spectrum disorders (ASD) to perform more advanced operations on an iPod-based speech-generating device (SGD). The effects of the teaching program were evaluated in a multiprobe multiple baseline across participants design that included two intervention phases. The first intervention focused on teaching the students to navigate between two screen pages and complete a multi-step response sequence to request preferred stimuli. The second intervention aimed to teach the students to turn on and unlock the device prior to navigating to the correct screen pages. Teaching procedures included response prompting, prompt fading, and differential reinforcement. Results showed that both interventions were effective in teaching the respective operations. Learning advanced operation of the iPod-based SGD could be seen as one way to promote greater independence in using such devices for multi-step communication.  相似文献   
72.
van der Meer A  Husby A 《Laterality》2006,11(3):263-276
Cradling is an interactive activity, involving a manual component that is very often an integral part of cradling. Cradling, while doing something else with the free hand, is referred to here as functional cradling. This study examined the relationship between a person's handedness and what arm he or she prefers to use when functionally cradling a baby doll that resembles a newborn infant. A total of 765 participants took part in the experiment, 403 women and 362 men, between the ages of 4 and 86 years. Left- and mixed-handers were actively recruited. The sample consisted of 64.3% right-handed, 24.7% mixed-handed, and 11.0% left-handed participants. The results showed a clear tendency for participants to cradle in their non-dominant arm (p < .001). Furthermore, this tendency increased with age and it was present in both sexes, although significantly stronger in women than in men. On the other hand, experience with young children through younger siblings and/or being a parent did not increase the likelihood to cradle in the non-dominant arm. It is concluded that humans have a clear functional cradling preference for the non-dominant arm because this enables the dominant arm to engage in other tasks. This might also explain why previous studies have reported a universal left cradling bias because a right-handed majority (intuitively) keeps the dominant hand free when cradling.  相似文献   
73.
Neuropeptide hormones produced by neurosecretory cells in the central or peripheral nervous systems regulate various physiological and behavioral events during insect development and reproduction. PBAN/Pyrokinin is a major neuropeptide family, characterized by a 5‐amino‐acid C‐terminal sequence, FXPRLamide. This family of peptides has been implicated in regulating various physiological functions including, pheromone biosynthesis, muscle contraction, diapause induction or termination, melanization, and puparium formation in different insect species. In the present study, we report a new member of the PBAN family from the red imported fire ant, Solenopsis invicta, Soi‐PBAN, composed of 26‐AA (GSGEDLSYGDAYEVDEDDHPLFVPRL). Three additional peptides were deduced from Soi‐PBAN cDNA: 15‐AA (TSQDIASGMWFGPRL), 8‐AA (QPQFTPRL) and 9‐AA (LPWIPSPRL), that correspond to diapause hormone (DH), β‐neuropeptide (NP), and γ‐NP, which are found in many lepidopteran moths. Five peptides, DH, α, β, γ NPs, and PBAN are encoded from PBAN genes of lepidopteran moths, but in the fire ant the α‐NP is missing. Each of the four synthetic peptides from the fire ant Soi‐PBAN cDNA showed significant pheromonotropic activity in a moth model, indicating that these peptides are cross‐reactive. Soi‐β‐NP induced the highest amount of pheromone production of the four peptides evaluated. The Soi‐DH homologue had the lowest pheromonotropic activity, but was still significantly greater than control values. When the deduced amino acid sequences (entire ORF domains) from Soi‐PBAN cDNA were compared with other known sequences, the fire ant was most similar to the honey bee, but phylogenetically distant from moth and beetle species. Soi‐PBAN (26‐AA) unlike the other three peptides shows a low degree of sequence identity with honeybee PBAN (33‐AA). Based on the amino acid sequences encoded from insect PBAN genes identified to date, neuropeptide diversity is correlated with the taxonomic or phylogenetic classification of Insecta. From the present study we report the first neuropeptide identified and characterized from the central nervous system of Formicidae.  相似文献   
74.
75.
Prospective control when catching moving toys was studied longitudinally in full-term and preterm infants between the ages of 22 and 48 weeks. The toy’s distance and time to the catching place and its velocity were explored as possible timing strategies used by infants to start their hand movement. The aim of the study was to find evidence for a shift in timing strategy and whether there were differences between full-term and preterm infants. In addition, it was investigated how infants continuously guided their hands to the toy and whether this guidance was influenced by their use of timing strategy. The toy approached the infants from the side with different constant velocities and constant accelerations. Results showed that there was little difference between full-term and preterm infants’ use of timing strategies. Initially, infants used a distance- or velocity-strategy, possibly causing them to have many unsuccessful catches. After a shift to a time-strategy, infants appeared to increase the number of successful catches and performed longer and more functional tau-couplings between the hand and the toy. One preterm infant did not switch to a time-strategy, and frequently missed the moving toy. The same infant also showed less functional tau-coupling with non-controlled collisions between the hand and the toy. More follow-up research is needed to investigate whether problems with extracting the relevant perceptual information for action could be an early indication of later perceptuo-motor difficulties.  相似文献   
76.
This study shows a significant correlation between functional connectivity, as measured with resting-state functional magnetic resonance imaging (MRI), and neuroanatomical connectivity, as measured with manganese-enhanced MRI, in rats at 10 weeks after unilateral stroke and in age-matched controls. Reduced interhemispheric functional connectivity between the contralesional primary motor cortex (M1) and ipsilesional sensorimotor cortical regions was accompanied by a decrease in transcallosal manganese transfer from contralesional M1 to the ipsilesional sensorimotor cortex after a large unilateral stroke. Increased intrahemispheric functional connectivity in the contralesional sensorimotor cortex was associated with locally enhanced neuroanatomical tracer uptake, which underlines the strong link between functional and structural reorganization of neuronal networks after stroke.  相似文献   
77.

Introduction

Activated protein C (APC) resistance is associated with an increased risk of venous thrombosis. High levels of estradiol and progesterone, e.g. during ovarian stimulation and pregnancy, as well as exogenously administered estrogens and progestagens during oral contraceptive use, induce an acquired form of APC resistance. Several coagulation factors display a cyclic pattern during the menstrual cycle due to the fluctuation of estradiol and progesterone. The aim of the study was to evaluate whether varying levels of estradiol and progesterone during the menstrual cycle are associated with differences in sensitivity to APC.

Materials and methods

Normalized APC sensitivity ratios (nAPCsr) were determined with the thrombin generation-based APC-resistance test at six different time points during the menstrual cycle in thirteen wildtype women and six women with factor VLeiden.

Results

Mean nAPCsr varied slightly during the menstrual cycle. Women without factor VLeiden were more likely to have lower nAPCsr at the beginning of the cycle than later on in the cycle (1.34 versus 1.54 and 1.58, Friedman ranking test p = 0.009).

Conclusions

The sensitivity to APC differs between the different phases of the menstrual cycle. This cyclic variability could be useful in improving studies on APC resistance in women.  相似文献   
78.
To investigate how individual differences in moral judgmentcompetence are reflected in the human brain, we used event-relatedfunctional magnetic resonance imaging, while 23 participantsmade either socio-normative or grammatical judgments. Participantswith lower moral judgment competence recruited the left ventromedialprefrontal cortex and the left posterior superior temporal sulcusmore than participants with greater competence in this domainwhen identifying social norm violations. Moreover, moral judgmentcompetence scores were inversely correlated with activity inthe right dorsolateral prefrontal cortex (DLPFC) during socio-normativerelative to grammatical judgments. Greater activity in rightDLPFC in participants with lower moral judgment competence indicatesincreased recruitment of rule-based knowledge and its controlledapplication during socio-normative judgments. These data supportcurrent models of the neurocognition of morality according towhich both emotional and cognitive components play an importantrole.  相似文献   
79.
80.
As part of a large, prospective study we investigated the prevalence Helicobacter pylori serum antibodies in children with recurrent abdominal pain (RAP). All patients suffered from recurrent bouts of abdominal pain for at least 6 months and ranged in age from 6 to 12 years. H. pylori antibodies were detected using an enzyme-linked immunosorbent assay. The prevalence of H. pylori antibodies in the RAP group was compared to that of a control group which consisted predominantly of pre-operative children. None of the control group suffered or had suffered from RAP. Antibodies to H. pylori were found in 7 of 82 (8.5%) RAP patients and in 2 of 39 (5.1%) control children. The latter difference is not significant and suggests that RAP is only rarely caused in children by H. pylori infection.  相似文献   
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