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101.
为克服 He-Ne激光血管内照射疗法所具有的不足,我们采用830nm、500mW半导体激光器,研制了用于体外血管照射的激光治疗仪.设计了易于固定的激光输出头,并且采用单片机控制整机,提高了仪器的稳定性和可靠性.临床应用取得了令人满意的治疗效果.  相似文献   
102.
The neurofibromatosis 1 (NF1) gene encodes a protein neurofibromin, which contains a glutamyl transpeptidase (GTP)-activating protein (GAP)-related domain: NF1 GRD. This domain is able to down-regulate P21ras by stimulating its intrinsic GTPase. Because P2lras has an important role in regulating growth and differentiation, somatic mutations in the NF1 gene may result in mutant neurofibromins that might interfere with the Ras signaling pathway and contribute to the development of tumors. In this study, we used polymerase chain reaction (PCR)-coupled single-stranded conformational polymorphism (SSCP) and DNA sequencing to examine possible mutations in the NF1 GRD in human pituitary tumors. We screened 36 nonfunctioning and 20 growth hormone—secreting adenomas. No mutation was detected in these tumors. Our results indicate that inactivation of neurofibromin may not have a primary role in the formation of pituitary adenomas.  相似文献   
103.
The status of training in clinical genetics and genetic counseling in Asia is at diverse stages of development and maturity. Most of the training programs are in academic training centers where exposure to patients in the clinics or in the hospital is a major component. This setting provides trainees with knowledge and skills to be competent geneticists and genetic counselors in a variety of patient care interactions. Majority of the training programs combine clinical and research training which provide trainees a broad and integrated approach in the diagnosis and management of patients while providing opportunities for research discoveries that can be translated to better patient care. The background on how the training programs in clinical genetics and genetic counseling in Asia evolved to their current status are described. Each of these countries can learn from each other through sharing of best practices and resources.  相似文献   
104.
本研究运用荧光金(FG)逆行束路追踪与5-HT1A受体免疫荧光组织化学染色技术相结合,观察了大鼠腰骶髓后连合核(DCN)和中间带外侧核(IML)内感受盆腔内脏伤害性信息并向外侧臂旁核(LPB)发出投射的神经元呈5-HT1A受体免疫反应阳性。将FG注入一侧LPB后,可在腰骶节段(L6-S2)观察到大量的FG逆标神经元,这些FG逆标神经元主要集中于DCN和IML内,以同侧为主;5%福尔马林注入大鼠结肠后,Fos蛋白阳性神经元主要分布于腰骶髓DCN和IML,以同侧为主,在同侧脊髓背角I层、II层和深层也有少量的分布。另外,在腰骶髓DCN和IML内,还可观察到大量5-HT1A受体阳性的神经元胞体、纤维和终末,同时有部分Fos蛋白阳性的FG逆标神经元呈5-HT1A受体阳性。上述结果提示,大鼠腰骶髓DCN和IML内的5-HT能终末可能对盆腔内脏伤害性信息的传递发挥调控作用。  相似文献   
105.
We studied the clinicopathologic, immunophenotypic, and cytogenetic features of 26 patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) associated with serum IgM paraprotein. The study group (16 men; 10 women; median age, 64 years; range, 40-82 years) represents approximately 2.5% of CLL/SLL cases at our institution. The paraprotein level ranged from 1 to 14 g/L (median, 4 g/L). Neoplasms in bone marrow were composed of small round lymphocytes arranged in nodular (n = 6), diffuse (n = 5), interstitial (n = 5), or mixed (n = 10) patterns. All cases were positive for monotypic surface immunoglobulin light chain, IgM/IgD, CD5, CD19, CD20, and CD23. CD11c (14/20 [70%]), CD79b (11/19 [58%]), FMC-7 (11/26 [42%]), CD22 (8/20 [40%]), and ZAP-70 (6/19 [32%]) were expressed in subsets of cases. Of 17 bone marrow specimens assessed by conventional cytogenetics, 6 were abnormal and 11 were diploid. The overall survival of this group (median follow-up, 24 months) was not significantly different from that for an age-, sex-and stage-matched group of 52 CLL/SLL patients without IgM paraprotein (P = .60). We conclude that CLL/SLL cases with serum IgM paraprotein are similar to other CLL/SLL cases in their clinicopathologic and immunophenotypic features.  相似文献   
106.
107.
介绍了“四川联大Ⅰ型”(以下简称:SUUⅠ)管外流式(ELF)中空纤维膜式氧合器的研制、设计、外形制做及离心封端等过程,重点介绍了中空纤维膜材料选择,膜肺离心封端的原理、材料、设备及方法,并对聚氨酯胶进行离心封端的具体步聚作了较详细的叙述。作者根据自身在国外与国内的研制经验,认为离心封端的关键在于:(1)中空纤维膜材料的质量及成束质量;(2)聚氨酯封端胶材料固化特性的掌握及料量计算;(3)反应温度控制;(4)气体排除;(5)转速的控制;(6)纤维束的安装;(7)脱模和切头的时间掌握等方面。作者用外购的材料和自己设计制造的离心封端机成功地制造了我国第一个管外流式(ELF)中空纤维成人氧合器。SUUⅠ膜式氧合器的设计是作者在国外建立的交叉流式膜肺O2、CO2传递模型的具体应用。  相似文献   
108.
Osteoporosis and obesity are two severe complex diseases threatening public health worldwide. Both diseases are under strong genetic determinants as well as genetically correlated. Aiming to identify pleiotropic genes underlying obesity and osteoporosis, we performed a bivariate genome-wide association (GWA) meta-analysis of hip bone mineral density (BMD) and total body fat mass (TBFM) in 12,981 participants from seven samples, and followed by in silico replication in the UK biobank (UKB) cohort sample (N = 217,822). Combining the results from discovery meta-analysis and replication sample, we identified one novel locus, 17q21.31 (lead SNP rs12150327, NC_000017.11:g.44956910G > A, discovery bivariate P = 4.83 × 109, replication P = 5.75 × 105) at the genome-wide significance level (ɑ = 5.0 × 10−8), which may have pleiotropic effects to both hip BMD and TBFM. Functional annotations highlighted several candidate genes, including KIF18B, C1QL1, and PRPF19 that may exert pleiotropic effects to the development of both body mass and bone mass. Our findings can improve our understanding of the etiology of osteoporosis and obesity, as well as shed light on potential new therapies.Subject terms: Genome-wide association studies, Gene expression profiling  相似文献   
109.
企业员工应对方式与心理健康之间的关系   总被引:3,自引:2,他引:3  
目的:验证不同应对方式对心理健康的单独与共同影响。方法:对4745名被试用分层回归的方法分析不同应对方式对心理健康的单独影响和交互作用。结论:单独使用“消极应对”的应对方式,对心理健康水平存在不利影响;而单独使用“积极应对”的应对方式能在一定程度上改善心理健康水平。“消极应对”与“积极应对”两种应对方式结合使用能显著改善心理健康水平,比单独使用这两种应对方式对心理健康更有利。  相似文献   
110.
Angiomyolipoma (AML) is the most common benign mesenchymal tumor of the kidney. It belongs to the family of perivascular epithelioid cell tumors and is typically composed of blood vessels, adipose tissue, and smooth muscle- like cells, which are characteristically positive for HMB-45. Results of recent studies suggest that p53 mutation may play an important role in AML progression. Here, we describe a locally destructive renal AML in a patient with tuberous sclerosis. The tumor consisted of mostly epithelioid cells with marked nuclear pleomorphism and frequent mitoses and was positive for HMB-45. The diagnosis of atypical epithelioid AML was made. Codon alteration in the p53 gene was not detected, despite focal p53 immunoreactivity and single nucleotide polymorphism at exon 6. Our finding indicates no definite link between p53 abnormalities and the atypical appearance of AML. To the best of our knowledge, this is the second renal AML case investigated for p53 mutations.  相似文献   
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