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101.
102.
Infectious coryza, an upper respiratory tract disease in chickens, caused by Avibacterium paragallinarum, leads to huge economic losses. The disease is controlled through vaccination; but vaccination efficacy is dependent on correct identification of the infecting serovar, as limited cross-protection is reported amongst some serovars. Current identification methods include the heamagglutination inhibition test, which is demanding and could be subjective. To overcome this, molecular typing methods proposed are the Multiplex polymerase chain reaction (PCR) and Restriction Fragment Length Polymorphism-PCR, but low reproducibility is reported. Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR has been suggested for molecular groupings of various bacterial species. This study focuses on evaluating the ERIC-PCR as a probable method to differentiate between different Av. paragallinarum serovars by grouping with reference isolates, based on clonal relations. The ERIC-PCR was performed on 12 reference isolates and 41 field isolates originating from South Africa and South America. The data indicate that the ERIC-PCR is not ideal for the differentiation or for molecular typing of Av. paragallinarum serovars, as no correlation is drawn upon comparison of banding patterns of field isolates and reference strains. However, the results do indicate isolates from the same origin sharing unique banding patterns, indicating potential clonal relationship; but when compared to the reference isolates dominant in the specific area, no correlation could be drawn. Furthermore, although the ERIC-PCR serves a purpose in epidemiological studies, it has proved to have little application in differentiating amongst serovars of Av. paragallinarum and to group untyped field strains with known reference strains.  相似文献   
103.
Ewing sarcoma is a highly malignant tumor of bone preferentially arising in children and young adults. Its 5-year survival rate is only 50% despite the use of multimodal therapeutic approaches, requiring a search for new therapeutic targets and the development of novel therapeutic modalities. KIT and PDGFRs are type III receptor tyrosine kinases, and activating mutations in c-kit (which encodes KIT) and PDGFRs have been reported as oncogenic events in many malignancies. Imatinib is a selective inhibitor of KIT, PDGFR, and ABL tyrosine kinase activity and exerts different anti-tumor effects according to the regions of mutations in c-kit and PDGFR genes. Thus, we evaluated the immunohistochemical expression of KIT protein and the mutational status of exons 9, 11, 13, and 17 of the c-kit gene, exons 12 and 18 of the PDGFRA gene, and exon 12 of the PDGFRB gene in 71 formalin-fixed, paraffin-embedded Ewing sarcomas to increase our understanding of the potential, if any, of imatinib treatment for this malignancy. Of the 71 samples, 27 (38%) were immunohistochemically positive for KIT; however, activating mutations in c-kit were found in only 2 of 71 Ewing sarcomas (2.6%) within exon 9. No activating mutations in the PDGFRA and PDGFRB genes were found, but pleomorphism was identified in exon 18 of the PDGFRA gene. Our results for KIT protein expression agree with those of previous studies. This is the largest series of c-kit mutational analysis in Ewing sarcoma to date, and the results definitively show that c-kit activating mutations are not coincident with KIT protein expression in Ewing sarcoma in most samples. These findings imply other mechanisms for KIT activity and leave open the question of whether imatinib would be efficacious in the treatment of Ewing sarcoma.  相似文献   
104.
BACKGROUND: A substantial proportion of patients with bipolar disorder are characterized by a rapidly cycling course and are particularly resistant to conventional treatment. METHODS: This secondary analysis, defined a priori, was conducted on a larger data set from patients with bipolar I disorder to determine the efficacy of a 3-week treatment with the atypical antipsychotic olanzapine (5-20 mg/day, n=19) versus placebo (n=26) in patients with >or=4 episodes in the preceding year. RESULTS: Significantly fewer placebo patients completed treatment (34.6 vs. 73.7%, P=0.016), and more than half discontinued due to lack of efficacy (53.8 vs. 21.1%, P=0.035). Olanzapine reduced Young Mania Rating Scale (YMRS) total scores significantly more than placebo (-13.9 vs. -4.1, P=0.011). Clinical responses, defined as >or=50% improvement in YMRS, were achieved in 58% of olanzapine patients, compared with 28% of placebo patients (P=0.066). Extrapyramidal symptoms were not significantly changed in either group. Somnolence was the most common adverse event in both groups (olanzapine: 52.6%, placebo: 23.1%; P=0.060). No event occurred significantly more frequently with olanzapine than with placebo. No patients discontinued due to an adverse event. LIMITATIONS: The duration of this study was limited to 3 weeks, precluding conclusions about long-term efficacy of olanzapine. Moreover, a sizeable placebo effect was obtained, possibly masking optimal therapeutic effect. Despite these limitations, treatment differences in efficacy were highly significant. CONCLUSIONS: These results indicate that olanzapine was effective in reducing symptoms of mania and well tolerated in patients with bipolar I disorder with a rapid-cycling course.  相似文献   
105.
We performed molecular, enzyme, and metabolic studies in 50 patients with D ‐2‐hydroxyglutaric aciduria (D ‐2‐HGA) who accumulated D ‐2‐hydroxyglutarate (D ‐2‐HG) in physiological fluids. Presumed pathogenic mutations were detected in 24 of 50 patients in the D ‐2‐hydroxyglutarate dehydrogenase (D2HGDH) gene, which encodes D ‐2‐hydroxyglutarate dehydrogenase (D ‐2‐HGDH). Enzyme assay of D ‐2‐HGDH confirmed that all patients with mutations had impaired enzyme activity, whereas patients with D ‐2‐HGA whose enzyme activity was normal did not have mutations. Significantly lower D ‐2‐HG concentrations in body fluids were observed in mutation‐positive D ‐2‐HGA patients than in mutation‐negative patients. These results imply that multiple genetic loci may be associated with hyperexcretion of D ‐2‐HG. Accordingly, we suggest a new classification: D ‐2‐HGA Type I associates with D ‐2‐HGDH deficiency, whereas idiopathic D ‐2‐HGA manifests with normal D ‐2‐HGDH activity and higher D ‐2‐HG levels in body fluids compared with Type I patients. It remains possible that several classifications for idiopathic D ‐2‐HGA patients with diverse genetic loci will be revealed in future studies. Hum Mutat 31:1–5, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
106.
107.
STUDY OBJECTIVES: REM sleep behavior disorder (RBD) is a common manifestation of Parkinson disease (PD) which is characterized by dream-enacting behaviors, unpleasant dreams, and loss of muscle atonia during REM sleep. Dopaminergic mechanisms are thought to play a role in RBD pathogenesis. To further asses such a role, we have evaluated the effect of pramipexole, a dopamine receptor agonist, on RBD features in PD patients. SETTING: University hospital sleep disorder center. PARTICIPANTS: Eleven PD patients with untreated RBD. interventions: Not applicable. MEASUREMENTS AND RESULTS: In a prospective study, 11 consecutive PD patients with untreated RBD on levodopa monotherapy were placed on pramipexole to further ameliorate their parkinsonism. The effects on RBD were evaluated before and 3 months after stable pramipexole therapy through patient and bed partner interviews and blind assessment of video-polysomnographic measures. Pramipexole improved parkinsonism in all patients. Patients and bed partners reported no significant changes in frequency and severity of the abnormal RBD related motor and vocal sleep behaviors or the frequency of unpleasant dreams. Video-polysomnography analyses showed no differences in RBD related sleep measures including tonic submental electromyographic activity, phasic submental electromyographic activity, percentage of REM sleep time spent with abnormal behaviors, and severity of the abnormal behaviors detected on the videotapes. CONCLUSION: In PD, pramipexole improved parkinsonism but did not modify RBD related symptoms and objective video-polysomnographic abnormalities. This observation suggests that in PD, dopamine mechanisms do not play a central role in the pathogenesis of RBD.  相似文献   
108.
BACKGROUND: To evaluate the 12-week outcomes (effectiveness, tolerability, and patterns of medication use) of olanzapine (either in antimanic monotherapy or in combination with other antipsychotics, anticonvulsants, and/or lithium) in patients with bipolar mania or mixed mania. METHOD: EMBLEM (European Mania in Bipolar Longitudinal Evaluation of Medication) is a 24-month prospective observational study of in- and outpatients with acute mania/mixed mania conducted in 14 European countries. Primary outcome measures included Clinical Global Impressions-Bipolar Disorder scale (overall, mania, and depression); 5-item Hamilton Depression Rating Scale; and Young Mania Rating Scale. Tolerability measures included a questionnaire to assess patients' symptomatic complaints. RESULTS: Overall, 2004 patients received olanzapine (olanzapine monotherapy, n=673; olanzapine combination, n=1331). Concomitant therapy with antidepressants and/or anxiolytics was possible in both groups. The countries significantly differed in the use of olanzapine monotherapy versus olanzapine combination (p<.0001). Baseline-to-endpoint changes on the CGI-BP subscales, YMRS, and HAMD-5 were significant within both treatment groups (p<.0001). Olanzapine monotherapy was generally better tolerated than olanzapine combination, particularly with regard to sedation (12% vs 17%; p<.001), tremor (2% vs 5%; p<.001), and akathisia (3% vs 6%; p<.001). DISCUSSION: The acute-phase EMBLEM results suggest that in naturalistic settings, olanzapine (both as monotherapy and combination) may be effective in treating patients with bipolar mania. The use of olanzapine monotherapy or combination varies significantly across countries, but combination is generally the rule, rather than the exception.  相似文献   
109.
BACKGROUND: More and more epidemiological, genetic and neuroimaging studies show similarities between bipolar disorder (BD) and schizophrenia (SZ). Cognitive functions are known to be highly impaired in SZ and are increasingly studied in BD. When both populations are compared, the conclusions appear to be contradictory. The purpose of this review is to help define the profile of cognitive deficits in BD and in SZ. METHODS: A systematic review of the literature of neuropsychological studies comparing BD and SZ was made, beginning in January 1990 and ending in January 2005. Thirty-eight studies met the required quality criteria and were included in this review. RESULTS: Bipolar patients exhibit extensive cognitive abnormalities with a pattern of deficits that is not unique to this disease. However, when compared to schizophrenic patients, bipolar patients demonstrate a lesser degree of deficits, particularly concerning premorbid and current intelligence quotient and perhaps attention, verbal memory and executive functions. When looking into effect sizes, there seem to be different profiles even in studies finding no significant differences. CONCLUSIONS: The neuropsychological differences reported between both groups could be due to the presence of psychotic features, to environmental factors (stressful events, duration of the disease and number of hospitalisations) and could also be related to differences during the neurodevelopmental phase. Further studies should confirm whether these results are truly related to different neurobiological backgrounds.  相似文献   
110.
Activation of the cardiac "sympathetic afferent" reflex (CSAR) has been reported to depress the arterial baroreflex and enhance the arterial chemoreflex via a central mechanism. In the present study, we used single-unit extracellular recording techniques to examine the effects of stimulation of cardiac sympathetic afferents on baro- or chemosensitive neurons in the nucleus tractus solitarius (NTS) in anesthetized rats. Of 54 barosensitive NTS neurons tested for their response to epicardial application of capsaicin (0.4 microg), 38 were significantly (P<0.01) inhibited by 38% while 16 did not respond. Of 42 NTS chemosensitive neurons tested for their response to capsaicin, 33 were significantly (P<0.01) excited by 47% while 9 did not respond. In addition, of 12 both barosensitive and chemosensitive NTS neurons tested for capsaicin, 2 were excited, 7 were inhibited, and 3 did not respond. In conclusion, this study indicates that CSAR activation inhibited NTS barosensitive neurons and excited NTS chemosensitive neurons, suggesting that the NTS plays an important role in processing the interactions between these cardiovascular reflexes.  相似文献   
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