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61.
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Within Europe, classical genetic markers, nuclear autosomal and Y-chromosome DNA polymorphisms display an east-west frequency gradient. This has been taken as evidence for the westward migration of Neolithic farmers from the Middle East. In contrast, most studies of mtDNA variation in Europe and the Middle East have not revealed clinal distributions. Here we report an analysis of dys44 haplotypes, consisting of 35 polymorphisms on an 8 kb segment of the dystrophin gene on Xp21, in a sample of 1203 Eurasian chromosomes. Our results do not show a significant genetic structure in Europe, though when Middle Eastern samples are included a very low but significant genetic structure, rooted in Middle Eastern heterogeneity, is observed. This structure was not correlated to either geography or language, indicating that neither of these factors are a barrier to gene flow within Europe and/or the Middle East. Spatial autocorrelation analysis did not show clinal variation from the Middle East to Europe, though an underlying and ancient east-west cline across the Eurasian continent was detected. Clines provide a strong signal of ancient major population migration(s), and we suggest that the observed cline likely resulted from an ancient, bifurcating migration out of Africa that influenced the colonizing of Europe, Asia and the Americas. Our study reveals that, in addition to settlements from the Near East, Europe has been influenced by other major population movements, such as expansion(s) from Asia, as well as by recent gene flow from within Europe and the Middle East.  相似文献   
63.
The sinoatrial (SA) node is the cardiac pacemaker and changes in its adrenergic-muscarinic phenotype have been postulated as a determinant of age-associated modifications in heart rate variability. To address this question, right atria were microdissected, the SA node area was identified by acetylcholinesterase staining, and, using a RT-PCR method, the accumulation of mRNA molecules encoding β1- and β2-adrenergic (β1- and β2-AR) and muscarinic (M2-R) receptor was quantified to define the proportion between β-AR and M2-R mRNAs within the sinoatrial area of adult (3 months) and senescent (24 months) individual rat hearts. In adult hearts, the highest M2-R/β-AR mRNA ratio was observed within the sinoatrial area compared with adjacent atrial myocardium, while in the senescent hearts, no difference was observed between sinoatrial and adjacent areas. This change was specific of the sinoatrial area since adult and senescent whole atrial or ventricular myocardium did not differ in their M2-R/β-AR mRNA ratio, and was associated with a fragmentation of acetylcholinesterase staining of the senescent SA node. Quantitative changes in the expression of genes encoding proteins involved in heart rate regulation specifically affect the sinoatrial area of the senescent heart.  相似文献   
64.
In 2 unrelated families 9 males presented with ataxia, apraxia, and neuropsychological abnormalities or mental deficiency, inherited as an X-linked recessive syndrome with partial clinical expression in obligate female carriers. The symptoms were present in early childhood and were non-progressive. Additional findings in 2 males were congenital "club-feet" and generalized seizures. The affected males were 13-62 years old at the time of our examination. Chromosome abnormalities including fragile X fra(X) could not be demonstrated in any case. Results of metabolic screenings were also normal. The clinical picture with X-linked recessive inheritance distinguishes this syndrome from previously described inherited hereditary ataxias.  相似文献   
65.
新型微波热疗机研制及其临床应用   总被引:6,自引:0,他引:6  
重点对新型电脑微波热疗机的构成、测温控温方案进行了研究。采用自适应广义预测控制算法对热疗温度进行控制,解决了因更换不同辐射器导致对象特性变化使控制性能降低的问题,从而得到了满意的疗效。文中介绍了该仪器关键的硬件、软件设计,基本的特点和临床应用  相似文献   
66.
67.
Six cases of uncommon profunda femoris artery injury are analyzed. One half of the cases were not treated surgically at the time of injury and resulted in chronic arteriovenous fistulas. Even after operative correction, residual symptoms persisted in two of these three cases. The generous use of arteriography is recommended in cases of proximal thigh penetrating injuries to avoid this problem. Either repair or ligation of the injured vessel yielded the same good results. The postoperative hospital stay was short in all instances, ranging from four to eight days, and there were no deaths.  相似文献   
68.
采用多分辨率分析和人工神经网络相结合的方法实现对心室晚电位的检测。首先利用多分辨率分解技术提取高分辨率心电信号不同频带的能量构成一组特征值 ,再利用这些特征值训练BP神经网络 ,并完成对心室晚电位的识别。经过对 2 8例 3导高分辨率心电图实验数据的处理 ,取得了较高的识别准确率  相似文献   
69.
BACKGROUND: Because manic patients lack insight, they are generally considered unreliable observers of their own psychopathology. The present analyses sought to examine to what extent patient reports could improve formal diagnostic criteria for mania--and be validated against the Carroll-Klein (CK) psychobiological model of bipolarity. METHOD: 104 DSM-IV acutely manic (hospitalized) patients provided self-assessment on the Ahearn--Carroll scale, the Multiple Visual Analogue Scales of Bipolarity (MVAS-BP). A principal component analysis (PCA) was performed on MVAS-BP, and the data on factorial scores were then compared to dimensional scores according to the CK model and to factors on the Beigel-Murphy Manic State Rating Scale (MSRS) completed by psychiatrists. RESULTS: The PCA identified a general factor accounting for 33% of the total variance; after varimax rotation, seven independent factors emerged, essentially in coherence with the signs and symptoms of DSM-IV mania, except for the 'social disinhibition' factor, which does not figure out as a distinct criterion in DSM-IV. Strong correlations were obtained (r > or = 0.80) between the four major factors of MVAS-BP and the four dimensional categories of the CK model: 'Consummatory Reward' with F1 'Elation and Inflated Self-esteem' (r=0.93), 'Incentive Reward' with F2 'Activation' (r=0.84), 'Psychomotor Pressure' with F3 'Acceleration' (r=0.85), and 'Central Pain' with F4 'Anxiety-Depression' (r=0.84). The F2 'Activation' appeared to be strongly correlated (r > or = 0.70) to all categories of the CK model. Correlational analysis between the factor structure of MVAS-BP and the MSRS showed significant coefficients on the scores assessing the emotional factors of 'Elation' and 'Depression.' Among the MVAS-BP factors, only 'Activation' was correlated to the majority of clinician ratings as obtained by the MSRS. CONCLUSIONS: These findings provide overall construct validity to the DSM-IV criteria for mania. Self-assessment of this disorder appears feasible and potentially useful in practice; lack of insight, poor judgment, and distractibility obviously require assessment by a clinician. Although our data are correlational and require prospective validation, they nonetheless suggest that (1) activation should be raised to the status of the stem criterion for mania, (2) to specify mood as elated, depressive, anxious, or irritable, and (3) to give individual status to social disinhibition (indiscriminate gregariousness) as a core pathological behavior in mania. Combining clinician- and self-observation thus produces a more precise and complete phenomenology of mania. We finally submit that the foregoing reformulation provides a psychobiological basis to the manic construct as formulated in the Carroll-Klein model.  相似文献   
70.
OBJECTIVE: To investigate the incidence of chromosome 11 abnormality in acute myeloid leukemia and its relationship with the clinical aspects and prognosis. METHODS:Conventional cytogenetic analysis of R-band was used to detect the abnormalities of chromosome 11 in 356 acute myeloid leukemia patients. RESULTS: Thirty-four out of 356 patients (9.55%) had abnormalities of chromosome 11, of which 20 (58.8%) involved in 11q23, 7 (19.9%) had translocations involving 11p15, 5 (14.7%) had-11, and the rest had other abnormalities such as +11, and t(11;14). The incidence of 11q23 involvement in M4 and M5 was higher than other subtypes of acute myeloid leukemia (AML). Ten cases with 11q23 abnormality had additional cytogenetic aberrations. In 30 cases treated with chemotherapy, 13 cases acquired complete remission (CR). The CR rate was lower than that of whole cases of acute myeloid leukemia(34.3% versus 64.0%). The CR rate of AML with 11q23 abnormality was lower than that of AML with normal karyotype (25% versus 55.6%). In other 10 patients with additional chromosome aberrations, the CR rate was lower than that of AML with 11q23 alone. In 7 patients with translocations at 11p15, only 3 patients acquired CR, and 2 patients relapsed early. Only 2 patients acquired CR in 5 patients with-11. CONCLUSION: 11q23 was a frequent aberration in chromosome 11 anomaly, which was often detected in M4 and M5. It might be associated with the pathogenesis of acute monolytic leukemia. The patients with chromosome 11 anomaly had poorer prognosis.  相似文献   
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