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Functional neuroimaging results need to replicate to inform sound models of human social cognition and its neural correlates. Introspection, the capacity to reflect on one's thoughts and feelings, is one process required for normative social cognition and emotional functioning. Engaging in introspection draws on a network of brain regions including medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), middle temporal gyri (MTG), and temporoparietal junction (TPJ). Maturation of these regions during adolescence mirrors the behavioral advances seen in adolescent social cognition, but the neural correlates of introspection in adolescence need to replicate to confirm their generalizability and role as a possible mechanism. The current study investigated whether reflecting upon one's own feelings of sadness would activate and replicate similar brain regions in two independent samples of adolescents. Participants included 156 adolescents (50% female) from the California Families Project and 119 adolescent girls from the Pittsburgh Girls Study of Emotion. All participants completed the Emotion Regulation Questionnaire (ERQ) and underwent a functional magnetic resonance imaging scan while completing the same facial emotion‐processing task at age 16–17 years. Both samples showed similar whole‐brain activation patterns when engaged in sadness introspection and when judging a nonemotional facial feature. Whole‐brain activation was unrelated to ERQ scores in both samples. Neural responsivity to task manipulations replicated in regions recruited for socio‐emotional (mPFC, PCC, MTG, TPJ) and attention (dorsolateral PFC, precentral gyri, superior occipital gyrus, superior parietal lobule) processing. These findings demonstrate robust replication of neural engagement during sadness introspection in two independent adolescent samples.  相似文献   
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Various natural and synthetic polyanionic polymers with different chemical structures are known to exhibit potent antiviral activity in vitro toward a variety of enveloped viruses and may be considered as promising therapeutic agents. A water-soluble conjugate of 2,5-dihydroxybezoic acid (2,5-DHBA) with gelatin was synthesized by laccase-catalyzed oxidation of 2,5-DHBA in the presence of gelatin, and its antiviral activity against pseudorabies virus (PRV) and bovine herpesvirus type 1 (BoHV-1), two members of the Alphaherpesvirinae subfamily, was studied. The conjugate produced no direct cytotoxic effect on cells, and did not inhibit cell growth at concentrations up to 1000 µg/mL. It exhibited potent antiviral activity against PRV (IC50, 1.5–15 µg/mL for different virus strains) and BoHV-1 (IC50, 0.5–0.7 µg/mL). When present during virus adsorption, the conjugate strongly inhibited the attachment of PRV and BoHV-1 to cells. The 2,5-DHBA–gelatin conjugate had no direct virucidal effect on the viruses and did not influence their penetration into cells, cell-to-cell spread, production of infectious virus particles in cells, and expression of PRV glycoproteins E and B. The results indicated that the 2,5-DHBA–gelatin conjugate strongly inhibits the adsorption of alphaherpesviruses to cells and can be a promising synthetic polymer for the development of antiviral formulations against alphaherpesvirus infections.  相似文献   
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In a previous study, exercise and manual therapy demonstrated a 90% success rate in patients with osteoarthrosis of the temporomandibular joints in the short-term. The aim of this follow-up study was to assess the long-term effect of these treatment modalities. Seventeen patients were evaluated. All patients suffered from osteoarthrosis of the temporomandibular joints with pain in the temporomandibular joint at baseline and were treated successfully in a prior short-term study. The parameters were pain at rest and at chewing, impairment in daily life, and mouth opening. At follow-up, 11 patients (65%) experienced no pain and 13 patients (76%) had no pain at rest (Fisher's Exact Test: p<0.02). Thirteen patients (76%) had a normal incisal edge clearance, and ten patients (59%) felt no impairment due to the disease (Fisher's Exact Test: p=0.01). Thirteen patients (76%), who had been treated once successfully, have not needed treatment within the three years after cessation of their therapy. Exercise therapy is an effective tool to treat osteoarthrosis of the temporomandibular joints.  相似文献   
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Catheter-related thrombosis (CRT) occurs frequently during autologous hematopoietic cell transplantation (AHCT) and data regarding the incidence, risk factors, and management are understudied. We evaluated 789 consecutive patients with lymphoma and myeloma that underwent AHCT over 10 years (2006 to 2016) and detected the incidence of CRT was 6.3%; only 32% of CRT were symptomatic. The majority occurred within 100 days of AHCT (86%) and median time from tunneled line placement to CRT was 44 days (range, 11 to 89 days). Outcomes of these 50 patients with CRT were compared with age- and disease-matched AHCT control subjects to identify risk factors. History of prior venous thromboembolism (VTE) (20.9% versus 7.0%, P = .02) was the only significant risk factor. Treatment with low-molecular-weight heparin was tolerated with rare minor bleeding (4%), although CRT recurrence or extension (10%) and subsequent VTE (12%) were common. CRT did not impact on nonrelapse mortality or risk of relapse; 2-year progression-free survival was 55% in CRT cases versus 54% in control subjects (P = .42). CRT appears to be common in patients with lymphoma and myeloma undergoing AHCT and significantly contributes to morbidity. Further study to determine mitigating strategies and modify risk factors for CRT is warranted.  相似文献   
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Background

Over-activated microglia play a central role during neuroinflammation, leading to neuronal cell death and neurodegeneration. Reversion of over-activated to neuroprotective microglia phenotype could regenerate a healthy CNS-supporting microglia environment. Our aim was to identify a dataset of intracellular molecules in primary microglia that play a role in the transition of microglia to a ramified, neuroprotective phenotype.

Methods

We exploited the anti-inflammatory and neuroprotective properties of conditioned medium of adipose-derived mesenchymal stem cells (CM) as a tool to generate the neuroprotective phenotype of microglia in vitro, and we set up a microscopy-based siRNA screen to identify its hits by cell morphology.

Results

We initially assayed an array of 157 siRNAs against genes that codify proteins and factors of cytoskeleton and activation/inflammatory pathways in microglia. From them, 45 siRNAs significantly inhibited the CM-induced transition from a neurotoxic to a neuroprotective phenotype of microglia, and 50 siRNAs had the opposite effect. As a proof-of-concept, ten of these targets were validated with individual siRNAs and by downregulation of protein expression. This validation step resulted essential, because three of the potential targets were false positives. The seven validated targets were assayed in a functional screen that revealed that the atypical RhoGTPase RhoE/Rnd3 is necessary for BDNF expression and plays an essential role in controlling microglial migration.

Conclusions

Besides the identification of RhoE/Rnd3 as a novel inducer of a potential neuroprotective phenotype in microglia, we propose a list of potential targets to be further confirmed with selective activators or inhibitors.
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Derivation of periosteal and endosteal contours taken from transversal long bone cross‐sections limits the accuracy of calculated biomechanical properties. Although several techniques are available for deriving both contours, the effect of these techniques on accuracy of calculated cross‐sectional properties in non‐adults is unknown. We examine a sample of 86 non‐adult femora from birth to 12 years of age to estimate the effect of error in deriving periosteal and endosteal contours on cross‐sectional properties. Midshaft cross‐sections were taken from microCT scans and contours were derived using manual, fully automatic, spline, and ellipse techniques. Agreement between techniques was assessed against manually traced periosteal and endosteal contours using percent prediction error (%PE), reduced major axis analysis, and limits of agreement. The %PEs were highest in the medullary area and lowest in the total area. Mean %PEs were sufficiently below the 5% level of acceptable error, except for medullary areas, but individual values can greatly exceed this 5% boundary given the high standard deviation of %PE means and wide minimum–maximum range of %PEs. Automatic processing produces greater errors than does combination with manual, spline, and ellipse processing. Although periosteal contour is estimated with stronger agreement compared with endosteal contour, error in deriving periosteal contour has a substantially greater effect on calculated section moduli than does error in deriving endosteal contours. We observed no size effect on the resulting bias. Nevertheless, cross‐sectional properties in a younger age category may be estimated with greater error compared with in an older age category. We conclude that non‐adult midshaft cross‐sectional properties can be derived from microCT scans of femoral diaphyses with mean error of < 5% and that derivation of endosteal contour can be simplified by the ellipse technique because fully automatic derivation of endosteal contour may increase the resulting error, especially in small samples.  相似文献   
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