全文获取类型
收费全文 | 3752篇 |
免费 | 193篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 69篇 |
妇产科学 | 83篇 |
基础医学 | 484篇 |
口腔科学 | 71篇 |
临床医学 | 362篇 |
内科学 | 955篇 |
皮肤病学 | 26篇 |
神经病学 | 619篇 |
特种医学 | 120篇 |
外科学 | 395篇 |
综合类 | 11篇 |
一般理论 | 2篇 |
预防医学 | 171篇 |
眼科学 | 35篇 |
药学 | 209篇 |
中国医学 | 16篇 |
肿瘤学 | 264篇 |
出版年
2023年 | 26篇 |
2022年 | 58篇 |
2021年 | 97篇 |
2020年 | 63篇 |
2019年 | 86篇 |
2018年 | 104篇 |
2017年 | 75篇 |
2016年 | 113篇 |
2015年 | 107篇 |
2014年 | 154篇 |
2013年 | 192篇 |
2012年 | 278篇 |
2011年 | 247篇 |
2010年 | 155篇 |
2009年 | 141篇 |
2008年 | 249篇 |
2007年 | 250篇 |
2006年 | 239篇 |
2005年 | 254篇 |
2004年 | 223篇 |
2003年 | 195篇 |
2002年 | 192篇 |
2001年 | 28篇 |
2000年 | 23篇 |
1999年 | 37篇 |
1998年 | 58篇 |
1997年 | 29篇 |
1996年 | 16篇 |
1995年 | 32篇 |
1994年 | 19篇 |
1993年 | 18篇 |
1992年 | 22篇 |
1991年 | 13篇 |
1990年 | 24篇 |
1989年 | 14篇 |
1988年 | 9篇 |
1987年 | 14篇 |
1986年 | 9篇 |
1985年 | 13篇 |
1984年 | 16篇 |
1983年 | 10篇 |
1982年 | 16篇 |
1981年 | 6篇 |
1980年 | 8篇 |
1979年 | 7篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1974年 | 8篇 |
1973年 | 4篇 |
1970年 | 3篇 |
排序方式: 共有3969条查询结果,搜索用时 234 毫秒
991.
992.
993.
994.
D Ronchetti K Todoerti G Tuana L Agnelli L Mosca M Lionetti S Fabris P Colapietro M Miozzo M Ferrarini P Tassone A Neri 《Blood cancer journal》2012,2(11):e96
Small nucleolar RNAs (snoRNAs) and small Cajal body-specific RNAs (scaRNAs) are non-coding RNAs involved in the maturation of other RNA molecules and generally located in the introns of host genes. It is now emerging that altered sno/scaRNAs expression may have a pathological role in cancer. This study elucidates the patterns of sno/scaRNAs expression in multiple myeloma (MM) by profiling purified malignant plasma cells from 55 MMs, 8 secondary plasma cell leukemias (sPCLs) and 4 normal controls. Overall, a global sno/scaRNAs downregulation was found in MMs and, even more, in sPCLs compared with normal plasma cells. Whereas SCARNA22 resulted the only sno/scaRNA characterizing the translocation/cyclin D4 (TC4) MM, TC2 group displayed a distinct sno/scaRNA signature overexpressing members of SNORD115 and SNORD116 families located in a region finely regulated by an imprinting center at 15q11, which, however, resulted overall hypomethylated in MMs independently of the SNORD115 and SNORD116 expression levels. Finally, integrative analyses with available gene expression and genome-wide data revealed the occurrence of significant sno/scaRNAs/host genes co-expression and the putative influence of allelic imbalances on specific snoRNAs expression. Our data extend the current view of sno/scaRNAs deregulation in cancer and add novel information to the bio-molecular complexity of plasma cell dyscrasias. 相似文献
995.
Epidermal growth factor receptor (EGFR) gene copy number in colorectal adenoma-carcinoma progression
996.
997.
Metka KODRIC Giancarlo GARUTI Mario COLOMBAN Barbara RUSSI Rossana D. PORTA Mirco LUSUARDI Marco CONFALONIERI 《Respirology (Carlton, Vic.)》2009,14(3):424-428
Background and objective: Exacerbations of COPD are often characterized by increased mucus production that is difficult to treat and worsens patients' outcome. This study evaluated the efficacy of a chest physiotherapy technique (expiration with the glottis open in the lateral posture, ELTGOL) during acute exacerbations of COPD using as outcome measures sputum volume, length of hospitalization, reduction in dyspnoea (Borg score), improvement in quality of life (assessed by the St George Respiratory Questionnaire) and incidence of COPD exacerbations during follow up.
Methods: The study recruited 59 patients hospitalized for the treatment of acute exacerbation of COPD, who were randomly assigned to a control group and an intervention group. The control group was treated with standard medical therapy while the intervention group was treated with ELTGOL plus medical therapy. A subgroup of patients was followed for 6 months to verify the effects on COPD exacerbations and need for hospitalizations.
Results: At the time of hospital discharge there was no significant difference between the two groups in the outcome measures, with the exception of the Borg score, which was significantly improved in the ELTGOL group (4.3 ± 1.5 in the control group vs 3.0 ± 1.8 in the ELTGOL group, P = 0.004). After 6 months there was no significant difference in the other measured parameters between a subset of the groups available for follow up. During follow up, the ELTGOL group had numerically fewer exacerbations and less need for hospitalization though differences were not statistically significant.
Conclusions: Chest physiotherapy using the ELTGOL technique has a limited role in patients with mild exacerbation of moderate to severe COPD with a tendency towards fewer exacerbations and hospitalizations. 相似文献
Methods: The study recruited 59 patients hospitalized for the treatment of acute exacerbation of COPD, who were randomly assigned to a control group and an intervention group. The control group was treated with standard medical therapy while the intervention group was treated with ELTGOL plus medical therapy. A subgroup of patients was followed for 6 months to verify the effects on COPD exacerbations and need for hospitalizations.
Results: At the time of hospital discharge there was no significant difference between the two groups in the outcome measures, with the exception of the Borg score, which was significantly improved in the ELTGOL group (4.3 ± 1.5 in the control group vs 3.0 ± 1.8 in the ELTGOL group, P = 0.004). After 6 months there was no significant difference in the other measured parameters between a subset of the groups available for follow up. During follow up, the ELTGOL group had numerically fewer exacerbations and less need for hospitalization though differences were not statistically significant.
Conclusions: Chest physiotherapy using the ELTGOL technique has a limited role in patients with mild exacerbation of moderate to severe COPD with a tendency towards fewer exacerbations and hospitalizations. 相似文献
998.
Zoccolella S Beghi E Palagano G Fraddosio A Samarelli V Lamberti P Lepore V Serlenga L Logroscino G;SLAP registry 《Journal of the neurological sciences》2006,250(1-2):45-49
BACKGROUND: The El Escorial and the revised Airlie House diagnostic criteria for amyotrophic lateral sclerosis (ALS) were introduced to select patients for clinical trials. Heterogeneity of clinical presentation at onset and delay in diagnosis may decrease the likelihood for trial entry. OBJECTIVE: Identify risk factors for delay in the diagnosis and trial exclusion. METHODS: ALS incident cases were identified with El Escorial (EEC) and Airlie House criteria (AHC) through a population-based registry established in Puglia, Southern Italy, in the years 1998-99. RESULTS: 130 ALS incident cases were diagnosed with a median interval between onset of symptoms and diagnosis of 9.3 months and not different across both EEC and AHC categories. Twenty percent of cases were not eligible for clinical trials according to the AHC. About 5% of subjects in this series died with only lower motor neuron signs. Predictors for delay in the diagnosis were age between 65 and 75 years and spinal onset while fasciculations and cramps as first symptoms were predictors of exclusion from trials. CONCLUSIONS: In this population-based series, diagnostic delay was longer in subjects with spinal onset and age between 65 and 75 and fasciculation as first symptoms. About 80% of incident cases were trial eligible with AHC criteria. However, a significant number of subjects with ALS, characterized by a limited spread of signs, were not trial eligible while alive. 相似文献
999.
Animal and epidemiologic studies suggest that nonsteroidal anti-inflammatory drugs (NSAIDs) decrease the incidence of Parkinson disease (PD). The authors studied 1,258 PD cases and 6,638 controls from the General Practice Research Database. The odds ratios (95% CI) for ever vs never use were 0.93 (0.80 to 1.08) for nonaspirin NSAIDs, 1.29 (1.05 to 1.58) for aspirin, and 1.16 (1.00 to 1.35) for acetaminophen. Nonaspirin NSAID use was associated with a higher risk in women and a lower risk in men. 相似文献
1000.
Amadio S Pluchino S Brini E Morana P Guerriero R Martinelli Boneschi F Comi G Zaratin P Muzio V del Carro U 《Muscle & nerve》2006,33(2):265-273
We tested cortical motor evoked potentials (cMEPs) as a quantitative marker for in vivo monitoring of corticospinal tract damage in a murine multiple sclerosis model (experimental autoimmune encephalomyelitis, EAE). The cMEPs, previously standardized in naive C57BL/6 developing and adult mice, were studied longitudinally in adult EAE mice. Central conduction times (CCTs) increased significantly shortly before the earliest clinical signs developed (10 days postimmunization, dpi), with peak delay in acute EAE (20-40 dpi). In clinically stable disease (80 dpi), CCTs did not increase further, but cMEP amplitude declined progressively, with complete loss in >80% of mice at 120 dpi. Increase in CCT correlated with presence of inflammatory infiltrates and demyelination in acute EAE, whereas small or absent cMEPs were associated with continuing axonal damage in clinically-stabilized disease and beyond (>80 dpi). These results demonstrate that cMEPs are a useful method for monitoring corticospinal tract function in chronic-progressive EAE, and provide insight into the pathological substrate of the condition. 相似文献