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81.
A case of bladder toxoplasmosis in a 57-year-old male Caucasian patient was diagnosed with difficulty due to misleading clinical presentation. The patient presented with pollakiuria and urination burning. Imagery showed pseudotumoral thickening of the vesicle wall. Previously unknown status of HIV infection was found positive through the diagnosis of bladder toxoplasmosis. The patient died rapidly from neurological complications. This is the second published case in which bladder toxoplasmosis reveals an HIV infection.  相似文献   
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83.
Perceptual objects often comprise a visual and auditory signature that arrives simultaneously through distinct sensory channels, and cross-modal features are linked by virtue of being attributed to a specific object. Continued exposure to cross-modal events sets up expectations about what a given object most likely "sounds" like, and vice versa, thereby facilitating object detection and recognition. The binding of familiar auditory and visual signatures is referred to as semantic, multisensory integration. Whereas integration of semantically related cross-modal features is behaviorally advantageous, situations of sensory dominance of one modality at the expense of another impair performance. In the present study, magnetoencephalography recordings of semantically related cross-modal and unimodal stimuli captured the spatiotemporal patterns underlying multisensory processing at multiple stages. At early stages, 100 ms after stimulus onset, posterior parietal brain regions responded preferentially to cross-modal stimuli irrespective of task instructions or the degree of semantic relatedness between the auditory and visual components. As participants were required to classify cross-modal stimuli into semantic categories, activity in superior temporal and posterior cingulate cortices increased between 200 and 400 ms. As task instructions changed to incorporate cross-modal conflict, a process whereby auditory and visual components of cross-modal stimuli were compared to estimate their degree of congruence, multisensory processes were captured in parahippocampal, dorsomedial, and orbitofrontal cortices 100 and 400 ms after stimulus onset. Our results suggest that multisensory facilitation is associated with posterior parietal activity as early as 100 ms after stimulus onset. However, as participants are required to evaluate cross-modal stimuli based on their semantic category or their degree of congruence, multisensory processes extend in cingulate, temporal, and prefrontal cortices.  相似文献   
84.
Activation of endothelial cells is often associated with the cellular proliferation in vitro . CD105 is a more specific marker of activated endothelial cells from tumor vessels and Ki-67 is used to assess the proliferation status of both tumor and endothelial cells. The aim of the present study was to evaluate the status of endothelial cells using CD105 and Ki-67 immunohistochemistry in benign and malignant lesions of the uterine cervix. Double stain for CD105/Ki-67 in benign and malignant lesions of the uterine cervix showed that these two markers had divergent expression on endothelial cells from associated tumor blood vessels dependent on lesion type and proliferation status of tumor cells. Absence of CD105/Ki-67 coexpression in endothelial cells was correlated with histopathology of the uterine cervix lesions and tumor proliferative status. The present findings suggest that CD105 expression is an early event, specific for premalignant lesions of the uterine cervix, while endothelial proliferation assessed on Ki-67 combined with the lack of CD105 expression is often associated with invasive cervical carcinoma.  相似文献   
85.
86.
Purposes:   To describe the clinical spectrum and to evaluate the efficacy of different therapeutic agents in children with electrical status epilepticus in sleep (ESES).
Methods:   Clinical data of all patients with ESES (not including patients with Landau-Kleffner syndrome) in four pediatric neurology outpatient clinics were analyzed. Thirty patients with ESES had been treated between 1994 and 2007.
Results:   Eleven (37%) children had benign partial epilepsies of childhood, five (17%) had cerebral palsy, five (17%) had hydrocephalus, one (3%) had schizencephaly, one (3%) had prenatal parenchymal bleeding, and the etiology was unclear in seven (23%). The duration of ESES ranged between 2 and 60 months. The antiepileptic drugs that were found to be efficacious were: levetiracetam (41%), clobazam (31%), and sulthiame (17%). Valproic acid, lamotrigine, topiramate, and ethosuximide showed no efficacy. Steroids were efficacious in 65%; immunoglobulins were efficacious in 33%. High-dose diazepam was efficacious in 37%, but all the children had temporary response. Seventeen patients (57%) had cognitive deterioration, whereas the rest presented with regression in attention, speech, communication, and behavior. Fourteen children had permanent cognitive deficit. There was a significant correlation (p = 0.029) between the duration of ESES and residual intellectual deficit at follow-up.
Conclusions:   ESES reflects an evolution of benign partial epilepsy of childhood in more than one-third of the patients, whereas there is an underlying structural brain anomaly in another one-third. The most efficacious antiepileptic drugs (AEDs) are levetiracetam and clobazam. The duration of ESES correlated significantly with residual intellectual deficit at follow-up.  相似文献   
87.

Objective

Previous studies have revealed a phosphatase and tensin homolog (PTEN)–dependent interaction between the sphingolipid agonist dihydrosphingosine 1‐phosphate (dhS1P) and the transforming growth factor β/Smad3 signaling pathway. This study was undertaken to examine responses of systemic sclerosis (SSc) fibroblasts to sphingosine 1‐phosphate (S1P) and dhS1P and to gain further insight into the regulation of the S1P/dhS1P/PTEN pathway in SSc fibrosis.

Methods

Fibroblast cultures were established from skin biopsy samples obtained from patients with SSc and matched healthy controls. Western blotting and quantitative polymerase chain reaction were used to measure protein and messenger RNA levels, respectively. PTEN protein was examined in skin biopsy samples by immunohistochemistry.

Results

PTEN protein levels were low in SSc fibroblasts and correlated with elevated levels of collagen and phospho‐Smad3 and reduced levels of matrix metalloproteinase 1 (MMP‐1). Treatment with dhS1P restored PTEN levels and normalized collagen and MMP‐1 expression, as well as Smad3 phosphorylation status in SSc fibroblasts. S1P was strongly profibrotic in SSc and control fibroblasts. Distribution of S1P receptor isoforms was altered in SSc fibroblasts, which had reduced levels of S1P receptor 1 and S1P receptor 2 and elevated levels of S1P receptor 3. Only depletion of S1P receptor 1 abrogated the effects of dhS1P and S1P in control dermal fibroblasts. In contrast, depletion of either S1P receptor 1 or S1P receptor 2 prevented the effects of S1P and dhS1P in SSc fibroblasts.

Conclusion

Our findings demonstrate that PTEN deficiency is a critical determinant of the profibrotic phenotype of SSc fibroblasts. The antifibrotic effect of dhS1P is mediated through normalization of PTEN expression, suggesting that dhS1P or its derivatives may be effective as therapeutic antifibrotic agents. The distribution and function of S1P receptors differ in SSc and healthy fibroblasts, suggesting that alteration in the sphingolipid signaling pathway may contribute to SSc fibrosis.
  相似文献   
88.

Objective

Anti–citrullinated protein antibodies (ACPA) exhibit unique specificity for rheumatoid arthritis. However, it is incompletely understood whether and how ACPA contribute to disease pathogenesis. The Fc part of human IgG carries 2 N‐linked glycan moieties that are crucial for the structural stability of the antibody and that modulate both its binding affinity to Fcγ receptors and its ability to activate complement. We undertook this study to analyze Fc glycosylation of IgG1 ACPA in serum and synovial fluid (SF) in order to further characterize the immune response to citrullinated antigens.

Methods

ACPA were isolated by affinity purification using cyclic citrullinated peptides as antigen. IgG1 Fc glycosylation was analyzed by mass spectrometry. ACPA IgG1 glycan profiles were compared with glycan profiles of total serum IgG1 obtained from 85 well‐characterized patients. Glycan profiles of paired SF and serum samples were available from 11 additional patients.

Results

Compared with the pool of serum IgG1, ACPA IgG1 lacked terminal sialic acid residues. In SF, ACPA were highly agalactosylated and lacked sialic acid residues, a feature that was not detected for total SF IgG1. Moreover, differential ACPA glycan profiles were detected in rheumatoid factor (RF)–positive and RF‐negative patients.

Conclusion

ACPA IgG1 exhibit a specific Fc‐linked glycan profile that is distinct from that of total serum IgG1. Moreover, Fc glycosylation of ACPA differs markedly between SF and serum. Since Fc glycosylation directly affects the recruitment of Fc‐mediated effector mechanisms, these data could further our understanding of the contribution of ACPA to disease pathogenesis.
  相似文献   
89.

Background  

"Pay for performance" is an incentive system that has been gaining acceptance in medicine and is currently being considered for implementation in dentistry. However, it remains unclear whether pay for performance can effect significant and lasting changes in provider behavior and quality of care. Provider acceptance will likely increase if pay for performance programs reward true quality. Therefore, we adopted a quality-oriented approach in reviewing those factors which could influence whether it will be embraced by the dental profession.  相似文献   
90.
The basal ganglia and cerebellum are major subcortical structures that influence not only movement, but putatively also cognition and affect. Both structures receive input from and send output to the cerebral cortex. Thus, the basal ganglia and cerebellum form multisynaptic loops with the cerebral cortex. Basal ganglia and cerebellar loops have been assumed to be anatomically separate and to perform distinct functional operations. We investigated whether there is any direct route for basal ganglia output to influence cerebellar function that is independent of the cerebral cortex. We injected rabies virus (RV) into selected regions of the cerebellar cortex in cebus monkeys and used retrograde transneuronal transport of the virus to determine the origin of multisynaptic inputs to the injection sites. We found that the subthalamic nucleus of the basal ganglia has a substantial disynaptic projection to the cerebellar cortex. This pathway provides a means for both normal and abnormal signals from the basal ganglia to influence cerebellar function. We previously showed that the dentate nucleus of the cerebellum has a disynaptic projection to an input stage of basal ganglia processing, the striatum. Taken together these results provide the anatomical substrate for substantial two-way communication between the basal ganglia and cerebellum. Thus, the two subcortical structures may be linked together to form an integrated functional network.  相似文献   
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