全文获取类型
收费全文 | 6704篇 |
免费 | 513篇 |
国内免费 | 367篇 |
专业分类
耳鼻咽喉 | 128篇 |
儿科学 | 141篇 |
妇产科学 | 112篇 |
基础医学 | 738篇 |
口腔科学 | 68篇 |
临床医学 | 998篇 |
内科学 | 978篇 |
皮肤病学 | 53篇 |
神经病学 | 490篇 |
特种医学 | 252篇 |
外国民族医学 | 4篇 |
外科学 | 631篇 |
综合类 | 761篇 |
预防医学 | 461篇 |
眼科学 | 188篇 |
药学 | 751篇 |
1篇 | |
中国医学 | 241篇 |
肿瘤学 | 588篇 |
出版年
2024年 | 15篇 |
2023年 | 68篇 |
2022年 | 172篇 |
2021年 | 243篇 |
2020年 | 201篇 |
2019年 | 173篇 |
2018年 | 176篇 |
2017年 | 164篇 |
2016年 | 181篇 |
2015年 | 212篇 |
2014年 | 317篇 |
2013年 | 297篇 |
2012年 | 398篇 |
2011年 | 474篇 |
2010年 | 299篇 |
2009年 | 219篇 |
2008年 | 310篇 |
2007年 | 388篇 |
2006年 | 353篇 |
2005年 | 357篇 |
2004年 | 280篇 |
2003年 | 237篇 |
2002年 | 245篇 |
2001年 | 137篇 |
2000年 | 158篇 |
1999年 | 201篇 |
1998年 | 129篇 |
1997年 | 136篇 |
1996年 | 116篇 |
1995年 | 108篇 |
1994年 | 106篇 |
1993年 | 80篇 |
1992年 | 83篇 |
1991年 | 69篇 |
1990年 | 62篇 |
1989年 | 67篇 |
1988年 | 44篇 |
1987年 | 37篇 |
1986年 | 40篇 |
1985年 | 26篇 |
1984年 | 26篇 |
1983年 | 18篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 14篇 |
1977年 | 21篇 |
1973年 | 6篇 |
1965年 | 8篇 |
排序方式: 共有7584条查询结果,搜索用时 0 毫秒
21.
The method for detecting the number of living cells was studied. Using an adenosine triphosphate (ATP) bioluminescence assay, the present authors reported a perfect linear relationship between lg ATP concentrations and lg luminescence counts (r = 0.9963) as well as a relationship between lg number of cells and lg ATP luminescence counts (r = 0.9922). The detectable cells ranged from 10(2) to 10(6) cells/ml, the coefficients of variation 1-3%. This method is simple, accurate and sensitive and has a high reproducibility. 相似文献
22.
多普勒超声心动图评估左心室舒张末压的研究 总被引:1,自引:0,他引:1
目的探讨多普勒超声心动图评估左室舒张末压的有效方法与指标。方法对68例病人采用左心导管测压及经胸多普勒超声心动图检测。结果对比研究显示,联合肺静脉与二尖瓣血流频谱分析优于二尖瓣血流频谱分析,肺静脉A峰和二尖瓣A峰时限差值(PAd-Ad)与左室舒张末压实测值呈最佳相关性(r=0.72,P<0.01)。结论认为应用多普勒超声心动图测定PAd与Ad,并以其差值估测左室舒张末压,是一项简便、可靠的无创性评估左室舒张末压的方法。PAd-Ad≥0可作为临床判断左室舒张末压增高[≥2.0kPa(15mmHg)]的一项半定量指标。 相似文献
23.
24.
VEGF、MMP-2、MMP-9在卵巢原发性与转移性癌中表达的研究 总被引:1,自引:0,他引:1
目的 :探讨VEGF、MMP 2、MMP 9在卵巢原发上皮癌、库肯勃氏瘤中的表达差异及临床病理意义。方法 :采用免疫组化S P染色技术对 83例卵巢癌 (卵巢原发癌 4 5例、库肯勃氏瘤 38例 )进行分析 ,观察VEGF、MMP 2、MMP 9在卵巢癌中的表达。结果 :VEGF在卵巢原发癌和库肯勃氏瘤组织中的表达显著高于正常卵巢组织 (P <0 .0 5 ) ;MMP 2、MMP 9在正常卵巢组织中表达缺如 ;VEGF、MMP 2、MMP 9在卵巢原发癌与库肯勃氏瘤中表达均有显著差异 (P <0 .0 5 ) ;VEGF、MMP 2、MMP 9在库肯勃氏瘤中及卵巢原发癌中 ,任意两指标阳性表达均有正相关性 (P <0 .0 5 )。结论 :VEGF、MMP 2、MMP 9在库肯勃氏瘤的形成机制中起重要作用 ,与肿瘤的浸润转移密切相关 ,并可为鉴别卵巢原发癌与库肯勃氏瘤提供一定的依据 相似文献
25.
26.
目的 :探讨MMP 2、TIMP 2、Ki 67表达与库肯勃氏瘤病理生物学行为的关系。方法 :采用免疫组化SP法对 32例库肯勃氏瘤组织和 10例正常卵巢组织进行MMP 2、TIMP 2和Ki 67表达的检测。结果 :MMP 2、TIMP 2、Ki 67在库肯勃氏瘤组织中的表达量显著高于正常卵巢组织 (P <0 .0 1)。有合并转移的库肯勃氏瘤中MMP 2、Ki 67高于无合并转移者 (P <0 .0 5 ) ,TIMP 2低于无合并转移者 (P <0 .0 5 )。MMP 2、Ki 67与术后生存时间呈负相关 (P <0 .0 1) ,TIMP 2与术后生存时间呈正相关 (P <0 .0 1)。结论 :MMP 2、TIMP 2、Ki 67在库肯勃氏瘤发生、发展中起重要作用 ,可作为判断卵巢转移癌恶性程度、临床分期和评估预后的临床参考指标 相似文献
27.
Polycystic ovary syndrome (PCOS) is associated with low-grade chronic inflammation.This was a retrospective case–control study.In the present study, the risk coefficients of neutrophil to lymphocyte ratio (NLR), high-sensitive C-reactive protein (hs-CRP), and mean platelet volume (MPV) in obese patients with PCOS were determined. This study was designed to investigate NLR, hs-CRP, and MPV levels in 68 obese patients with PCOS and 44 nonobese patients with PCOS, and our study group was matched with 47 obese and 43 nonobese controls, respectively.PCOS group had higher MPV, NLR, insulin, glucose, and HOMA-IR rates than those of the controls. Subgroup analyses revealed that the obese PCOS group had higher NLR, hs-CRP, and MPV levels compared to those of controls. The obese PCOS group had higher NLR, hs-CRP, and MPV levels compared to those of the nonobese PCOS group. The odds ratios and 95% confidence intervals of those variables (NLR, hs-CRP, MPV) were found significant (P < .05). NLR, hs-CRP, and MPV variables were found statistically significant in the analysis of receiver operating characteristics.Our study demonstrated that NLR, hs-CRP, and MPV levels are increased in patients with obese PCOS. 相似文献
28.
Tingting Pang Chang Liu Junjie Yao Jiahui Li Zhongxu Li Huijuan Lou Siyuan Lei Jiangchun Zhang Li Dong Yufeng Wang 《Medicine》2022,101(32)
Background:Osteoarthritis is a common degenerative disease with a high incidence, high disability rate, and poor prognosis. Clinical studies have shown that Bushen Huoxue formula can relieve joint swelling and pain and improve limb function and joint mobility, but there is a lack of high-quality scientific basis. Using network pharmacology and molecular docking technology to study the mechanism of Bushen Huoxue formula in the treatment of osteoarthritis.Methods:First, the active ingredients and corresponding target predictions of the formula were obtained through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and the China National Knowledge Infrastructure. Meanwhile, the osteoarthritis disease targets were obtained through the genome annotation database platform (GeneCards) and the DrugBank database, and the target proteins obtained above were standardized using the Uniprot (https://www.uniprot.org) database standardization of names. Then, the Venn diagram was created by taking the intersection of the active ingredient and the target of the disease, and the “active ingredient-target” network was constructed and analyzed using Cytoscape 3.7.2 software. At the same time, the intersecting targets were imported into the Search Tool for the Retrieval of Interaction Gene/Proteins database to build a protein-protein interaction network and to screen the core targets; the intersecting targets were visualized by using the Database for Annotation, Visualization and Integrated Discovery 6.8 database for gene ontology functional analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and construct the “active ingredient-target-pathway” network. Finally, the main active ingredients of the formula for tonifying the kidney and invigorating the blood were validated by molecular docking with the core targets.Results:A total of 194 active ingredients and 365 targets of the Bushen Huoxue formula were collected, 776 targets for osteoarthritis diseases and 96 targets for the intersection of active ingredients and diseases. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis yielded 104 relevant pathways, including tumor necrosis factor signaling pathways, cancer signaling pathways, nucleotide-binding oligomerization domain-like receptor signaling pathways, Toll-like receptors signaling pathways, and osteoclast differentiation, apoptosis, T-cell receptor signaling pathway, and other related pathways. The molecular docking results showed good binding of the main active ingredients to the core targets.Conclusion:This study shows that the treatment of osteoarthritis involves multicomponent, multitarget, and multipathway processes. The mechanism of anti-inflammatory, antioxidant, inhibition of cartilage matrix degradation, and reduction of subchondral bone destruction may be an important mechanism for the therapeutic effect. 相似文献
29.
Solid epoxy resin is highly desired in adhesives, electronic materials and coatings due to the attractive characteristics of solvent-free, highly efficient utilization and convenient storage and transportation. However, the challenges remain in fabricating high-toughness solid epoxy resin through a facile and efficient way. Here, a high-performance environment-friendly solid epoxy resin was fabricated by employing maleic anhydride grafted ethylene-vinyl acetate copolymer (EVA-g-MAH) as the flexibilizer via one-step banburying method. The results showed that the modified epoxy resin maintained a high glass transition temperature (Tg) and thermal stability, while its impact strength, tensile toughness and flexural toughness were significantly increased compared with the neat epoxy resin. The impact strength, tensile toughness and flexural toughness of R-EM10 are improved 138%, 195% and 149%, respectively. The EVA-g-MAH was introduced in the epoxy matrix as a separate phase to increase toughness via transfer stress and dissipated energy. The attractive properties of this facile fabrication process and the high-toughness, as well as the environment-friendly performance make this solid epoxy highly promising for large-scale industrial application.High-toughness and environment-friendly solvent free solid epoxy resin through a low-cost, facile and large-scale fabrication process. 相似文献
30.
Yuanjian Wu Yubo Zhang Musha Hamushan Wenjun Zhang Tao Zhang Xujun Li Pei Han Tengfei Lou 《Orthopaedic Surgery》2022,14(7):1294
ObjectiveTo describe our experience with the combined use of pedicled neurotrophic flap and distraction osteogenesis in the management of complex lower extremity injuries with composite bone and soft tissue defects and assess the functional and cosmetic results of this method.MethodsA pedicled flap with a marked perforator artery was applied for soft tissue coverage after radical debridement and temporary external fixation. In the second stage, the Ilizarov external fixator was used in place of the temporary external fixator for reconstruction of the segmental bone defect by distraction osteogenesis. Twenty‐five patients (16 men and nine women; mean age, 39.2 years) were treated by using this combined technique between 2008 and 2016. All cases were graded initially as Gustilo–Anderson grade IIIB open fractures. The soft tissue defect after radical debridement ranged from 9 cm × 5 cm to 14 cm × 11 cm, and the average size of segmental defect was 5.2 (Range, 2.5–8.5) cm. Seventeen of these patients had a history of local infection. The bone structure and function were evaluated by two independent evaluators using Paley''s criteria.ResultsTwenty‐five patients were followed up for an average of 28.96 (Range, 15–48) months. The distally based sural neurovascular flap was applied in 13 patients, and the greater saphenous neurocutaneous perforator flap in 12 patients. The flap area ranged from 10 cm × 5 cm to 14 cm × 12 cm. Sufficient coverage of soft tissue defect was achieved in all cases. All flaps survived completely without complications. The bone defects were corrected by a mean lengthening of 6.94 (Range, 4.5–9.5) cm. The residual discrepancy was <1 cm in all cases, which was not clinically significant. The function was evaluated as excellent in 12 patients and good in 13 patients. Bone results were graded as excellent in 18 patients and good in seven patients. Complications during treatment included pain, pin tract infections, ankle midfoot joint stiffness, and docking site nonunion. No recurrence of infection was observed in infected patients. All cases achieved successful limb salvage and satisfactory function recovery without recurrence of infection.ConclusionsThe combined technique of a perforator artery pedicled neurotrophic flap and distraction osteogenesis is an effective alternative approach in the salvage treatment of massively traumatized and chronically infected lower extremities. 相似文献