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1.
BACKGROUND: Results from studies in serotonin-1A (5-HT1A) knockout mice and previous positron emission tomography (PET) studies in humans imply a role for 5-HT1A receptors in normal state anxiety as well as in certain anxiety disorders. The objective of this study was to investigate 5-HT1A receptor binding potential (BP) in social anxiety disorder (SAD). METHODS: Using PET and [carbonyl-11C]WAY-100635, we compared a homogeneous group of 12 unmedicated, male SAD patients with 18 healthy control subjects (HC). A multivariate ANOVA with all regional BP values as dependent variables, age and four radiochemical variables as covariates was performed. RESULTS: We found a significantly lower 5-HT1A BP in several limbic and paralimbic areas but not in the hippocampus (p = .234) of SAD patients. The difference in 5-HT1A binding was most significant in the amygdala (-21.4%; p = .003). There was also a more than 20% lower 5-HT(1A) BP of SAD patients in the anterior cingulate cortex (p = .004), insula (p = .003), and dorsal raphe nuclei (p = .030). CONCLUSIONS: The lower 5-HT1A binding in the amygdala and mesiofrontal areas of SAD patients is consistent with 1) preclinical findings of elevated anxiety in 5-HT1A knockout mice, 2) a previous PET study in healthy volunteers showing an inverse correlation between 5-HT1A BP and state anxiety, and 3) another human PET study in patients with panic disorder showing reduced 5-HT1A binding, thus corroborating the potential validity of 5-HT1A receptors as targets in the treatment of human anxiety disorders.  相似文献   
2.
Membrane order was measured in the erythrocyte ghost membranes of DSM-III schizophreniform disorder (SF), DSM-III schizophrenic (SCZ) and DSM-III manic (bipolar) (M) patients and a group of age- and sex-matched controls. Fluorescence polarization with the probe 1,6-diphenyl1-1,3,5-hexatriene was used to determine the steady-state fluorescence anisotropy (rs). The SF group showed a significant increase in rsrs = 0.037) from the control group. Although the means were not significantly different, 3 of 8 Ms and 5 of 8 SCZs also had rs values > the highest control value. Thermotropic behavior of the membranes was evaluated over the range of 40 to 20°C. No difference among groups in membrane enthalpy was detected. Thus, the differences in rs appear to be associated with differences in entropy. Phosphatidylcholine (PC) levels, which were known to be abnormal in these patients, were compared with the rs values. A significant (P < 0.001, R= -0.63) linear correlation between rs and membrane PC levels was observed. Overall these data further support the view that unusual membrane biophysical factors may occur with high frequency in the psychoses and affective disorders.  相似文献   
3.
It has earlier been proposed by the author that the aetiology of schizophrenic symptomatology may be due to the presence of abnormally connected interhemispheric fibres which link specialised functions in the brains of schizophrenics that are not connected in normal subjects, and that the neuroleptic drugs may produce their action through a local anaesthetic-like effect in suppression of conduction in these fibres. This line of thought has been extended here to consider the possible mechanism of action of the neuroleptic drugs in more detail, as well as that of the tricyclic antidepressant drugs which are derivatives of the phenothiazine group. Pharmacological similarities with the local anaesthetics both structurally and functionally have been considered, as well as the effects that these drug groups may have in common with the lithium salts. It has been suggested that these drugs all produce their primary effect on cell membranes, though not necessarily at the synapse, that the time course of their clinical effect may correlate with their incorporation into various cell membranes within the CNS, and that they may thus bring about a fundamental alteration in cell membrane microstructure. The possible role of electroconvulsive therapy has also been considered. The corollary of this argument is that the affective disorders may be genetically determined diseases of cell membrane microstructure.  相似文献   
4.
深圳市龙岗区坪地外来工亚健康状态的研究   总被引:5,自引:0,他引:5  
目的 :探讨深圳市龙岗区坪地外来工亚健康状况及其影响因素 ,为预防亚健康提供科学依据。方法 :采用统一表格对 12 68深圳市龙岗区坪地外来工进行调查。结果 :外来工的平均年龄为 ( 2 4.96± 6.10 )a ,其亚健康状态总体发生率为 65 .3 0 %,男性亚健康状态发生率为 63 .2 1%,女性为 67.91%,男性和女性之间差异无统计学意义。亚健康状态主要影响因素为 :结婚与否、睡眠时间、工作时间、加班时间以及工作是否有压力和居住环境差等因素 ,而与吸烟、饮酒、文化程度等因素无相关。结论 :深圳龙岗区坪地外来工中普遍存在亚健康状态 ,其发生较高且与工作环境、工作时间、加班时间有密切关系 ,故应引起政府部门及社会各界高度重视 ,加强对外来工的健康保护  相似文献   
5.
以红色素基因全长cDNA作探针,20例正常人,26例双相型情感性精神病患者进行RFLP分析。SacI酶切显示:部分正常人和部分患者基因组DNA产生的7.5kb,4.8kb,4.5kb呈多态性改变的片段。正常人具多态改变的占45%,患者为46.2%,按X染色体数计,正常人出现7.5kb限制性片段的频率为14.3%,患者为32.4%,但两者差异不显著。  相似文献   
6.
Summary Animal studies have demonstrated that neuropeptides modulate nervous system functions. It has been postulated that disturbances in neuropeptide systems may be aetiological factors in psychiatric and neurological disorders. Neuropeptides related to ACTH/MSH, including ORG 2766, increase motivation and attention and facilitate recovery processes after nerve damage. These peptides may be effective during the early stage of dementia. Vasopressin and related peptides improve memory processes in animals and humans. In addition, these peptides influence social behaviour, mood and addictive behaviour. The non-opioid -type endorphins have neurolepticlike activities in animals and antipsychotic effects in a category of schizophrenic patients. Peptides related to CCK have also been found to be effective in these patients. Some neuropeptides, e.g. TRH and PLG, have been reported to exert antidepressant effects. Further research may eventually produce neuropeptides with therapeutic action in psychiatric and neurological diseases.Parts of this article were presented on the occasion of the inauguration ceremony of the Department of Psychiatry of the University of Mainz on April 2 and 3, 1987  相似文献   
7.
We conducted a comprehensive examination of the sensory visual event-related potential (ERP) of psychiatric patients and their relatives using a methodology that improves upon those used previously by other investigators. One hundred thirty-five patients at the onset of their first psychotic episode, 146 first-degree relatives of these patients, and 113 normal controls were exposed to light flashes of four different intensities while their ERPs were recorded from three central scalp sites. For most analyses, various ERP amplitude measures did not discriminate the different psychiatric groups or their relatives either from one another or from the normal controls. These findings indicate that patients with schizophrenia, schizophreniform disorder, and affective disorder at the early stage of their illness do not display significant deficits in the processing and regulation of simple sensory visual stimulation.  相似文献   
8.
不同注意偏移和言语材料对耳优势影响的初步分析   总被引:1,自引:0,他引:1  
对55名健康被试在:(1)无注意偏移,(2)注意右偏,(3)注意左偏等三种注意条件下进行了下述3项言语分听测验;1.分离语测验,2。数字测验,3.有鲜明形象意义词汇测验。分析了不同注意偏移和言语材料对耳优优势的影响,认为注意右偏可加强分听言语材料时的右耳优势,左偏可减弱右耳优势,不同言语材料获得耳优势的结果不同。  相似文献   
9.
Effect of blocking N-methyl-D-aspartic acid (NMDA) and non-NMDA-glutamatergic receptors on performance in the plus-maze was studied in male rats bilaterally cannulated into the nucleus accumbens (Acc). Rats were divided into seven groups that received either 1 microl injections of saline, (+/-)2-amino-7-phosphonoheptanoic acid (AP-7, 0.2, 0.5, or 1 microg) or 2,3 dioxo-6-nitro-1,2,3,4,tetrahydrobenzo-(f)quinoxaline-7-sulphonamide disodium (NBQX, 0.2, 0.5, or 1 microg) 15 min before testing. Time spent in open arm, time per entry, end arrivals, open, closed, and total arm entries, relationship between open-, closed-, and total arm entries, rearing, face-, head-, and body grooming, and number of fecal boli were recorded. Time spent in the open arm increased under AP-7 (0.5 and 1 microg; P<.01) and NBQX (1 microg; P<.05) treatment, whereas time per entry was increased only with AP-7 (1 microg; P<.05). Open arm entries were increased by the intermediate doses of AP-7 (0.5 microg; P<.01) and NBQX (0.5 microg; P<.05); end arrivals were increased by the intermediate dose of AP-7 (0.5 microg/1 microl, P<.05). The frequency of rearing, grooming, and closed arm entries was not affected by the treatment. We conclude that NMDA and non-NMDA-glutamatergic blockade in the Acc lead to a behavioral disinhibition of cortical influences with the median doses, but that at higher doses the blockers have an anxiolytic-like effect.  相似文献   
10.
Although the safety and efficacy of electroconvulsive therapy (ECT) is acknowledged by most, concern has repeatedly been expressed that the treatment may have some lasting effects on the brain. To study potential morphological changes, 22 patients with a history of ECT were submitted to a detailed clinical evaluation and a brain CT scan examination. Age- and sex-matched control subjects comprised a group of comparable patients, none of whom had received ECT, and a second control group of healthy volunteers. Patients had larger ventricle/brain ratios and cortical "atrophy" scores than normal controls, but no association was found between these radiological measures and a previous history of ECT. Hence, the present data are consistent with recent reports that affective disorders may be associated with enlarged brain ventricles, although the clinical significance of such findings remains unclear. In line with previous investigations age correlated significantly with cortical "atrophy" scores and ventricle/brain ratios for all subjects. Statistical tests of correlations between duration of illness, previous psychotropic drug exposure and CT scan appearances were mainly inconclusive.  相似文献   
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