全文获取类型
收费全文 | 8265篇 |
免费 | 521篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 238篇 |
妇产科学 | 149篇 |
基础医学 | 1318篇 |
口腔科学 | 166篇 |
临床医学 | 688篇 |
内科学 | 2254篇 |
皮肤病学 | 289篇 |
神经病学 | 753篇 |
特种医学 | 96篇 |
外科学 | 758篇 |
综合类 | 32篇 |
预防医学 | 604篇 |
眼科学 | 167篇 |
药学 | 611篇 |
中国医学 | 37篇 |
肿瘤学 | 583篇 |
出版年
2024年 | 8篇 |
2023年 | 61篇 |
2022年 | 134篇 |
2021年 | 296篇 |
2020年 | 168篇 |
2019年 | 271篇 |
2018年 | 271篇 |
2017年 | 201篇 |
2016年 | 215篇 |
2015年 | 248篇 |
2014年 | 333篇 |
2013年 | 388篇 |
2012年 | 677篇 |
2011年 | 657篇 |
2010年 | 366篇 |
2009年 | 318篇 |
2008年 | 565篇 |
2007年 | 510篇 |
2006年 | 521篇 |
2005年 | 474篇 |
2004年 | 442篇 |
2003年 | 412篇 |
2002年 | 401篇 |
2001年 | 96篇 |
2000年 | 108篇 |
1999年 | 124篇 |
1998年 | 60篇 |
1997年 | 47篇 |
1996年 | 52篇 |
1995年 | 34篇 |
1994年 | 23篇 |
1993年 | 30篇 |
1992年 | 35篇 |
1991年 | 43篇 |
1990年 | 33篇 |
1989年 | 18篇 |
1988年 | 27篇 |
1987年 | 25篇 |
1986年 | 25篇 |
1985年 | 9篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 9篇 |
1980年 | 8篇 |
1979年 | 8篇 |
1978年 | 11篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1967年 | 5篇 |
排序方式: 共有8821条查询结果,搜索用时 15 毫秒
61.
Osvaldo Santos Miodraga Stefanovska-Petkovska Ana Virgolino Ana Cristina Miranda Joana Costa Elisabete Fernandes Susana Cardoso Antnio Vaz Carneiro 《Nutrients》2021,13(3)
Self-management of health requires skills to obtain, process, understand, and use health-related information. Assessment of adolescents’ functional health literacy requires valid, reliable, and low-burden tools. The main objective of this study was to adapt and study the psychometric properties of the Newest Vital Sign for the Portuguese adolescents’ population (NVS-PTeen). Classic psychometric indicators of reliability and validity were combined with item response theory (IRT) analyses in a cross-sectional survey, complemented with a 3-month test-retest assessment. The NVS-PTeen was self-administered to students enrolled in grades 8 to 12 (12 to 17 years old) in a school setting. Overall, 386 students (191 girls) from 16 classes of the same school participated in the study (mean age = 14.5; SD = 1.5). Internal reliability of the NVS-PTeen was α = 0.60. The NVS-PTeen total score was positively and significantly correlated with Portuguese (r = 0.28) and mathematics scores (r = 0.31), school years (r = 0.31), and age (r = 0.19). Similar to the original scale (for the U.S.), the NVS-PTeen is composed of two dimensions, reading-related literacy and numeracy. Temporal reliability is adequate, though with a learning effect. IRT analyses revealed differences in difficulty and discriminative capacity among items, all with adequate outfit and infit values. Results showed that the NVS-PTeen is valid and reliable, sensible to inter-individual educational differences, and adequate for regular screening of functional health literacy in adolescents. 相似文献
62.
63.
Emilio D. Poggio Joshua J. Augustine Susana Arrigain Daniel C. Brennan Jesse D. Schold 《American journal of transplantation》2021,21(8):2824-2832
Current short-term kidney post–transplant survival rates are excellent, but longer-term outcomes have historically been unchanged. This study used data from the national Scientific Registry of Transplant Recipients (SRTR) and evaluated 1-year and 5-year graft survival and half-lives for kidney transplant recipients in the US. All adult (≥18 years) solitary kidney transplants (n = 331,216) from 1995 to 2017 were included in the analysis. Mean age was 49.4 years (SD +/-13.7), 60% male, and 25% Black. The overall (deceased and living donor) adjusted hazard of graft failure steadily decreased from 0.89 (95%CI: 0.88, 0.91) in era 2000–2004 to 0.46 (95%CI: 0.45, 0.47) for era 2014–2017 (1995–1999 as reference). Improvements in adjusted hazards of graft failure were more favorable for Blacks, diabetics and older recipients. Median survival for deceased donor transplants increased from 8.2 years in era 1995–1999 to an estimated 11.7 years in the most recent era. Living kidney donor transplant median survival increased from 12.1 years in 1995–1999 to an estimated 19.2 years for transplants in 2014–2017. In conclusion, these data show continuous improvement in long-term outcomes with more notable improvement among higher-risk subgroups, suggesting a narrowing in the gap for those disadvantaged after transplantation. 相似文献
64.
65.
66.
O. Garcia-Suarez F. J. Naves M. E. Del Valle I. Esteban E. Bronzetti E. Vazquez J. A. Vega 《Anatomy and embryology》1996,193(6):577-583
We investigated the expression of immunoreactivity (IR) for low- (p75) and high-affinity (trk proteins) neurotrophin-receptor proteins in adult human paravertebral-sympathetic ganglion neurons. Mouse monoclonal antibodies against the pan-neurotrophin-receptor p75, and rabbit polyclonal antibodies against specific epitopes of the intracytoplasmic domain on trk neurotrophin-receptor proteins were used in fresh unfixed and formaldehyde-fixed paraffin-embedded sympathetic ganglia. All adult human paravertebral-sympathetic neurons displayed trkA neurotrophin-receptor-like protein IR, 10% express trkC neurotrophin-receptor-like protein IR, 37–44% show p75 IR, and no IR was obtained for trkB neurotrophin-receptor-like protein. The intensity of immunostaining was independent of the neuron size. Labelling of non-neuronal tissues, especially blood-vessel walls, was observed for p75, trkA and trkC neurotrophin-receptor proteins. These results indicate that overlapping exists in the expression of p75 and trk neurotrophin-receptor proteins in adult human paravertebral-sympathetic neurons, and suggest that neurotrophins might act on these neurons. 相似文献
67.
Jose L. Ortiz José M. Vallés Miguel Martí-Cabrera Julio Cortijo Esteban J. Morcillo 《Naunyn-Schmiedeberg's archives of pharmacology》1996,353(2):200-206
There is currently interest in the potential use of selective inhibitors of cyclic nucleotide phosphodiesterases (PDE) in the treatment of asthma. In this study we examined the effects of three selective PDE inhibitors, milrinone (PDE III), rolipram (PDE IV) and zaprinast (PDE V), on the broncoconstriction produced by antigen and histamine, the airway hyperreactivity and microvascular leakage after aerosol exposure to platelet-activating factor (PAF) and antigen, and the antigen-induced eosinophil infiltration in guinea-pig lung. Inhaled rolipram (0.01–10 mg ml–1) inhibited dose dependently the bronchospasm produced by aerosol antigen (5 mg ml–1) an anaesthetised, ventilated guinea-pigs. Rolipram (10 mg ml–1) produced maximal inhibition of antigen-induced bronchoconstriction but only partial inhibition of the response to aerosol histamine (1 mg ml–1). Milrinone and zaprinast (each 10 mg ml–1) showed weak, or no, inhibitory effects against bronchoconstriction produced by aerosol antigen or histamine. Pretreatment with rolipram (10 mg kg–1, i.p.) prevented airway hyperreactivity to histamine which develops 24 h after exposure of conscious guinea-pigs to aerosol PAF (500 g ml–1) or antigen (5 mg ml–1). The pulmonary eosinophil infiltration obtained with 24 h of antigen-exposure was inhibited by rolipram. In contrast, milrinone and zaprinast (each 10 mg kg–1, i.p.) failed to reduce either the airway hyperreactivity of the eosinophil accumulation in these animals. Rolipram (1–10 mg ml–1) reduced the extravasation of Evans blue after aerosol PAF (500 g ml–1) at all airway levels while a lower dose (0.1 mg ml–1) was only effective at intrapulmonary airways. Rolipram (0.01–1 mg ml–1) markedly reduced airway extravasation produced by inhaled antigen (5 mg ml–1). Zaprinast (1–10 mg ml–1) was also effective against airway microvascular leakage produced by aerosol PAF or antigen while milrinone (10 mg ml–1) had no antiexudative effect. These data support previous suggestions that pharmacological inhibition of PDE IV results in anti-spasmogenic and anti-inflammatory effects in the airways and may be useful in the treatment of asthma. 相似文献
68.
Paredes Esteban RM Velasco Sánchez B Martínez-Victoria Muñoz JM Cuevas C García Ruiz M 《Cirugía pediátrica : organo oficial de la Sociedad Espa?ola de Cirugía Pediátrica》2000,13(4):170-171
We present 2-year-old patient with a allopecia lesions in scalp, and clinique diagnostic of Cutis Aplasia. The anatomopathologic study have diagnosed the lesions as Acquired Progressive Lymphangioma (APL). Is a rare vascular tumour that has a tendency to appear in childhood an to progress slowly over the years. It could present as a solitary erythematous macule or plaque and a simple excision is usually curative. Our patient is the youngest reported in the literature. 相似文献
69.
Iranzu González Enrique J Andreu Angel Panizo Susana Inogés Ana Fontalba José Luis Fernández-Luna Mirella Gaboli Luis Sierrasesúmaga Salvador Martín-Algarra Javier Pardo Felipe Prósper Enrique de Alava 《Clinical cancer research》2004,10(2):751-761
PURPOSE AND EXPERIMENTAL DESIGN: The stem cell factor/KIT receptor loop may represent a novel target for molecular-based therapies of Ewing tumor. We analyzed the in vitro impact of KIT blockade by imatinib in Ewing tumor cell lines. RESULTS: KIT expression was detected in 4 of 4 Ewing tumor cell lines and in 49 of 110 patient samples (44.5%) by immunohistochemistry and/or Western blot analysis. KIT expression was stronger in Ewing tumors showing EWS-FLI1 nontype 1 fusions. Despite absence of c-kit mutations, constitutive and ligand-inducible phosphorylation of KIT was found in all tumor cell lines, indicating an active receptor. Treatment with KIT tyrosine kinase inhibitor imatinib (0.5-20 micro M) induced down-regulation of KIT phosphorylation and dose response inhibition of cell proliferation (IC(50), 12-15 micro M). However, imatinib administered alone at doses close to IC(50) for growth inhibition (10 micro M) did not induce a significant increase in apoptosis. We then analyzed if blockade of KIT loop through imatinib (10 micro M) was able to increase the antitumor in vitro effect of doxorubicin (DXR) and vincristine (VCR), drugs usually used in Ewing tumor treatment. Addition of imatinib decreased in 15-20 and 15-36% of the proliferative rate of Ewing tumor cells exposed to DXR and VCR, respectively, and increased in 15 and 30% of the apoptotic rate of Ewing tumor cells exposed to the same drugs. CONCLUSIONS: Inhibition of Ewing tumor cell proliferation by imatinib is mediated through blockade of KIT receptor signaling. Inhibition of KIT increases sensitivity of these cells to DXR and VCR. This study supports a potential role for imatinib in the treatment of Ewing tumor. 相似文献
70.
Marta Ruiz Hiroya Kobayashi Juan José Lasarte Jesús Prieto Francisco Borrás-Cuesta Esteban Celis Pablo Sarobe 《Clinical cancer research》2004,10(8):2860-2867
PURPOSE: The purpose of this research was to identify promiscuous T-helper cell determinants (THd) from carcinoembryonic antigen (CEA) to be used to prime T-cell help for cancer therapy. CEA was selected because this antigen is expressed in an important variety of carcinomas. EXPERIMENTAL DESIGN: Potential promiscuous THd from CEA were predicted using available computer algorithms. Predicted peptides were synthesized and tested in binding experiments to different HLA-DR molecules. Binder peptides were then used to prime T-cell responses both in vitro and in vivo. RESULTS: Twenty 15-mer peptides from CEA were predicted to bind to different HLA-DR molecules. The promiscuous character of these peptides was demonstrated in binding experiments. Fifteen of 20 peptides tested were able to bind to HLA-DR4, but only CEA (625-639) was shown to be presented after processing of recombinant CEA. CEA (625-639) was also found to be presented by HLA-DR53. Moreover, immunization of HLA-DR4 transgenic mice with CEA (625-639) in conjunction with class I epitope OVA (257-264), induced a CTL response specific of OVA (257-264). CONCLUSIONS: CEA (625-639) might be a relevant promiscuous THd peptide for cancer therapy. 相似文献