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排序方式: 共有1596条查询结果,搜索用时 31 毫秒
91.
Spinks R Nopoulos P Ward J Fuller R Magnotta VA Andreasen NC 《Schizophrenia Research》2005,73(2-3):229-233
This study compares globus pallidus (GP) volume between neuroleptic naive patients with schizophrenia and healthy controls using structural MRI. The volume of the external segment of the GP (GPe) was positively correlated with the severity of global symptoms, as measured by the Scale for the Assessment of Negative Symptoms and Scale for the Assessment of Positive Symptoms (SANS/SAPS, Andreasen and Olsen, 1982). The volume for the GP, GPe, and internal segment (GPi) did not differ between groups. 相似文献
92.
Kjaergard H Nielsen PH Andreasen JJ Steinbrüchel D Andersen LI Rasmussen K Andersen HR Nielsen TT 《Scandinavian cardiovascular journal : SCJ》2004,38(3):143-146
OBJECTIVE: To calculate the incidence and analyse the indications and outcome after surgical revascularization within the first 30 days after randomization of 1572 patients with acute myocardial infarction (MI) associated with ST-segment elevation (STEMI). DESIGN: Data regarding the patients undergoing heart surgery within the first 30 days after randomization were collected. RESULTS: Three patients (0.2%) with acute STEMI and randomized to percutaneous coronary intervention (PCI) underwent emergent coronary artery bypass grafting (CABG). A total of 50 patients (3.2%), 30 in the PCI group and 20 in the fibrinolysis group were revascularized by surgery within the first 30 days after randomization. The most frequent indication for surgery in both groups was unstable angina pectoris, followed by left main stenosis. The incidence of postoperative complications was higher compared with the outcome after elective CABG. CONCLUSIONS: The incidence of emergency CABG in this study was low (0.2%) after treatment of acute MI with either PCI or fibrinolysis. The overall incidence within 30 days was 3.2%, however, the mortality is increased with a 30-day mortality of 10% in this high-risk patient group. 相似文献
93.
BACKGROUND: Factors such as poor insight, amotivation, suspiciousness, disorganized speech and attentional problems may interfere with the ability of acutely ill individuals with psychotic disorders to provide a valid account of their symptoms. This study was designed to determine the degree to which history provided by such subjects is consistent with that obtained from other sources. METHOD: Fifty-five subjects presenting with psychotic disorders were multiply evaluated with a semi structured interview, the Comprehensive Assessment of Symptoms and History (CASH), which includes the Scales for the Assessment of Negative and Positive symptoms (SANS and SAPS). One interviewer assessed the severity of the patient's symptoms in the previous month based solely on information provided by the patient. A second rater made symptom ratings based on information obtained from a "best informant". Following this, a consensus rating was established based on an extensive evaluation and review of all sources of information. An item-by-item comparison of the three sets of symptom ratings was then quantified by paired t-tests, simple and multiple correlations. RESULTS: Positive and negative symptoms ratings based on the subjects' report were significantly lower than the corresponding consensus ratings. However, those based on the informants' report did not differ from consensus ratings for negative symptoms. Information obtained from subjects and from informants together accounted for a majority of the variance of the consensus ratings. CONCLUSIONS: These findings demonstrate that assessment limited to patients' own reports are likely to underestimate psychopathology in acutely ill patients with psychotic disorders. Obtaining corroborative history from a family member may substantially improve the validity of the assessment of negative symptoms. 相似文献
94.
BACKGROUND: Changes in the volume of the caudate nucleus over time in patients with schizophrenia has been shown to be directly related to neuroleptic exposure. Few studies have evaluated caudate volume in subjects with schizophrenia who were neuroleptic naive at intake and treated exclusively with atypical neuroleptics. METHODS: Fourteen patients were matched by gender to 14 healthy controls and were evaluated over time using MRI. The patients were neuroleptic na?ve at intake and at follow-up had been treated exclusively with atypical neuroleptics. Difference scores were calculated for caudate volumes. Neuroleptic exposure was quantified using a dose-years formula. RESULTS: There was no difference between patients and controls in the amount of change over time in the volume of the caudate. However, the female patients had a negative correlation (r= - 0.74) between drug exposure and volume change while the male patients had a positive correlation (r = 0.63). Therefore, there was a significant gender effect on the relationship between atypical neuroleptic exposure and changes in the structure of the caudate over time (test for difference in correlations: z = 2.39, p = 0.016). CONCLUSIONS: The change in caudate nucleus volume over time with exposure to atypical neuroleptics may be sex-dependent. Atypical neuroleptic expsoure was associated with volume increase over time in the males, while exposure in females was associated with volume decrement over time. 相似文献
95.
Kennedy P Andreasen D Ehirim P King B Kirby T Mao H Moore M 《Journal of neural engineering》2004,1(2):72-77
Individuals with profound paralysis and mutism require a communication channel. Traditional assistive technology devices eventually fail, especially in the case of amyotrophic lateral sclerosis (ALS) subjects who gradually become totally locked-in. A direct brain-to-computer interface that provides switch functions can provide a direct communication channel to the external world. Electroencephalographic (EEG) signals recorded from scalp electrodes are significantly degraded due to skull and scalp attenuation and ambient noise. The present system using conductive skull screws allows more reliable access to cortical local field potentials (LFPs) without entering the brain itself. We describe an almost locked-in human subject with ALS who activated a switch using online time domain detection techniques. Frequency domain analysis of his LFP activity demonstrates this to be an alternative method of detecting switch activation intentions. With this brain communicator system it is reasonable to expect that locked-in, but cognitively intact, humans will always be able to communicate. 相似文献
96.
Transient increase in total tau but not phospho-tau in human cerebrospinal fluid after acute stroke 总被引:7,自引:0,他引:7
Hesse C Rosengren L Andreasen N Davidsson P Vanderstichele H Vanmechelen E Blennow K 《Neuroscience letters》2001,297(3):187-190
An increase in cerebrospinal fluid (CSF)-total-tau, and recently also in CSF-phospho-tau, has been found in Alzheimer's disease (AD). However, the mechanisms for these changes are not known. We examined longitudinal CSF samples from nine patients with acute stroke. As compared with baseline levels (day 0-1), CSF-total-tau showed an increase at day 2-3 (179%; P=0.018), day 7-9 (257%; P=0.003), and after 3 weeks (425%; P=0.002) and returned to normal levels after 3-5 months (140%; NS). In contrast, there was no significant change in CSF-phospho-tau. These findings suggest that total tau and phospho-tau in CSF reflect different pathogenic processes in the brain; total-tau the degree of neuronal damage and phospho-tau the phosphorylation state of tau and thus possibly the formation of neurofibrillary tangles. 相似文献
97.
O'Leary DS Block RI Turner BM Koeppel J Magnotta VA Ponto LB Watkins GL Hichwa RD Andreasen NC 《Neuroreport》2003,14(8):1145-1151
The effects of marijuana on brain perfusion and internal timing were assessed using [15O] water PET in occasional and chronic users. Twelve volunteers who smoked marijuana recreationally about once weekly, and 12 volunteers who smoked daily for a number of years performed a self-paced counting task during PET imaging, before and after smoking marijuana and placebo cigarettes. Smoking marijuana increased rCBF in the ventral forebrain and cerebellar cortex in both groups, but resulted in significantly less frontal lobe activation in chronic users. Counting rate increased after smoking marijuana in both groups, as did a behavioral measure of self-paced tapping, and both increases correlated with rCBF in the cerebellum. Smoking marijuana appears to accelerate a cerebellar clock altering self-paced behaviors. 相似文献
98.
Sáez-Valero J Costell M Sjögren M Andreasen N Blennow K Luque JM 《Journal of neuroscience research》2003,72(1):132-136
Reelin is an essential glycoprotein for correct cytoarchitectonic organization during CNS development. Its function in the adult brain is far less well understood, but altered brain and blood reelin levels have been reported in some psychiatric disorders, and the possibility has been considered of an involvement of the reelin signaling pathway in neurodegeneration. Here we report, for the first time, the presence of detectable levels of reelin in rat and human cerebrospinal fluid (CSF) and show evidence for the involvement of a 180-kDa reelin fragment in two neurodegenerative disorders. This fragment was analyzed by Western blotting in CSF samples from 13 healthy control individuals and 14 frontotemporal dementia (FTD) and 20 Alzheimer's disease (AD) patients. Increased CSF 180-kDa reelin was found in FTD (161.7 +/- 6.7 arbitrary units; a.u.) and AD (151.4 +/- 3.8 a.u.) compared with control individuals (141.4 +/- 1.2 a.u., P < 0.05). Our results strongly suggest the involvement of reelin signaling in neurodegenerative pathologies. 相似文献
99.
Cem Atbaşoglu E Schultz SK Andreasen NC 《The Journal of neuropsychiatry and clinical neurosciences》2001,13(3):336-341
An association of suicidality and depersonalization with akathisia has been reported, but it is not clear whether these phenomena are specific to akathisia or are nonspecific manifestations of distress. The authors used the Barnes Akathisia Rating Scale, Brief Psychiatric Rating Scale, and Hamilton Rating Scale for Depression (Ham-D) to examine the relationships between suicidality, depersonalization, dysphoria, and akathisia in 68 patients with schizophrenia or schizophreniform disorder. Akathisia was associated with higher scores on the Ham-D ratings of suicidality, depersonalization, and agitation. In a logistic regression model, depressive mood and subjective awareness of akathisia appeared to be the only predictors of suicidality and depersonalization, respectively. These findings support the association between akathisia and both suicidality and depersonalization. However, these symptoms appear to be nonspecific responses to accompanying depressive mood and the subjective awareness of the akathisia syndrome, respectively. 相似文献
100.
Sex differences in the absence of massa intermedia in patients with schizophrenia versus healthy controls 总被引:1,自引:0,他引:1
OBJECTIVE: To evaluate sexual dimorphism and incidence of absent massa intermedia (MI), a midline thalamic structure, in patients with schizophrenia and healthy controls. METHODS: Thin slice magnetic resonance images of the brain were obtained. The presence of MI was determined by viewing sagittal, coronal, and axial planes. RESULTS: In healthy controls, females had a significantly lower incidence of absent MI (13.56%) compared with males (32.08%). In patients with schizophrenia, there was a sex by diagnosis interaction. Female patients had significantly higher incidence of absent MI (32.76%) compared with their healthy controls (13.56%), whereas the male patients showed no difference in incidence of absent MI compared with their controls. CONCLUSION: The MI, a sexually dimorphic midline structure, is more commonly absent in female patients with schizophrenia. These results support the growing literature reporting structural aberration of the thalamus, as well as other midline structures in the brains of patients with schizophrenia. 相似文献