全文获取类型
收费全文 | 37308篇 |
免费 | 3096篇 |
国内免费 | 1352篇 |
专业分类
耳鼻咽喉 | 424篇 |
儿科学 | 684篇 |
妇产科学 | 622篇 |
基础医学 | 5423篇 |
口腔科学 | 990篇 |
临床医学 | 3627篇 |
内科学 | 6630篇 |
皮肤病学 | 628篇 |
神经病学 | 3125篇 |
特种医学 | 1340篇 |
外国民族医学 | 6篇 |
外科学 | 4744篇 |
综合类 | 3126篇 |
一般理论 | 8篇 |
预防医学 | 2321篇 |
眼科学 | 855篇 |
药学 | 3601篇 |
1篇 | |
中国医学 | 627篇 |
肿瘤学 | 2974篇 |
出版年
2023年 | 168篇 |
2022年 | 395篇 |
2021年 | 663篇 |
2020年 | 449篇 |
2019年 | 553篇 |
2018年 | 821篇 |
2017年 | 683篇 |
2016年 | 691篇 |
2015年 | 813篇 |
2014年 | 1084篇 |
2013年 | 1285篇 |
2012年 | 1743篇 |
2011年 | 1813篇 |
2010年 | 1138篇 |
2009年 | 917篇 |
2008年 | 1509篇 |
2007年 | 1677篇 |
2006年 | 1533篇 |
2005年 | 1359篇 |
2004年 | 1172篇 |
2003年 | 1057篇 |
2002年 | 935篇 |
2001年 | 2412篇 |
2000年 | 2347篇 |
1999年 | 1996篇 |
1998年 | 784篇 |
1997年 | 569篇 |
1996年 | 409篇 |
1995年 | 373篇 |
1994年 | 326篇 |
1993年 | 298篇 |
1992年 | 1077篇 |
1991年 | 952篇 |
1990年 | 848篇 |
1989年 | 934篇 |
1988年 | 835篇 |
1987年 | 766篇 |
1986年 | 721篇 |
1985年 | 628篇 |
1984年 | 403篇 |
1983年 | 333篇 |
1982年 | 193篇 |
1981年 | 147篇 |
1980年 | 128篇 |
1979年 | 214篇 |
1978年 | 93篇 |
1977年 | 90篇 |
1973年 | 99篇 |
1972年 | 95篇 |
1971年 | 98篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Background
Advanced Practice Registered Nurses (APRNs) provide access to cost-effective, high quality care. APRNs are underutilized in states that restrict their practice. Removing restrictions could expand access to quality health care, cost-effectively relieve the physician shortage, and contribute economically.Purpose
This study forecasts the health system and economic impacts of reducing practice restrictions for Florida APRNs.Methods
The analysis utilized a number of data sources and IMPLAN software and estimated changes in APRN supply given less restrictive practice laws, and consequential health system and economic benefits.Findings
Between 2013 and 2025 APRN full time equivalents could increase an additional 11% with less restrictive practice regulations. This could eliminate or reduce the shortage of different types of physicians. Health care cost-savings could be $50 to $493 per resident. There would be a number of general economic benefits.Discussion
A number of health system and economic benefits would ensue from less restrictive APRN regulation. 相似文献993.
Janet Prvu Bettger Vu Q.C. Nguyen J. George Thomas Tami Guerrier Qing Yang Mark A. Hirsch Terrence Pugh Gabrielle Harris Mary Ann Eller Carol Pereira Deanna Hamm Eric A. Rinehardt Matthew Shall Janet P. Niemeier 《Archives of physical medicine and rehabilitation》2018,99(6):1226-1231
Attention to health care quality and safety has increased dramatically. The internal focus of an organization is not without influence from external policy and research findings. Compared with other specialties, efforts to align and advance rehabilitation research, practice, and policy using electronic health record data are in the early stages. This special communication defines quality, applies the dimensions of quality to rehabilitation, and illustrates the feasibility and utility of electronic health record data for research on rehabilitation care quality and outcomes. Using data generated at the point of care provides the greatest opportunity for improving the quality of health care, producing generalizable evidence to inform policy and practice, and ultimately benefiting the health of the populations served. 相似文献
994.
Average spectral power changes at the hippocampal electroencephalogram in schizophrenia model induced by ketamine
下载免费PDF全文
![点击此处可从《Fundamental & clinical pharmacology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Luis Rafael L. Sampaio Lucas T.N. Borges Joyse M.F. Silva Francisca Roselin O. de Andrade Talita M. Barbosa Tatiana Q. Oliveira Danielle Macedo Ricardo F. Lima Leonardo P. Dantas Manoel Cláudio A. Patrocinio Silvânia M.M. Vasconcelos 《Fundamental & clinical pharmacology》2018,32(1):60-68
The use of ketamine (Ket) as a pharmacological model of schizophrenia is an important tool for understanding the main mechanisms of glutamatergic regulated neural oscillations. Thus, the aim of the current study was to evaluate Ket‐induced changes in the average spectral power using the hippocampal quantitative electroencephalography (QEEG). To this end, male Wistar rats were submitted to a stereotactic surgery for the implantation of an electrode in the right hippocampus. After three days, the animals were divided into four groups that were treated for 10 consecutive days with Ket (10, 50, or 100 mg/kg). Brainwaves were captured on the 1st or 10th day, respectively, to acute or repeated treatments. The administration of Ket (10, 50, or 100 mg/kg), compared with controls, induced changes in the hippocampal average spectral power of delta, theta, alpha, gamma low or high waves, after acute or repeated treatments. Therefore, based on the alterations in the average spectral power of hippocampal waves induced by Ket, our findings might provide a basis for the use of hippocampal QEEG in animal models of schizophrenia. 相似文献
995.
996.
997.
Purpose
This study assessed the anti-inflammatory effect and mechanism of action of hinokitiol in human corneal epithelial (HCE) cells.Methods
HCE cells were incubated with different concentrations of hinokitiol or dimethylsulfoxide (DMSO), which served as a vehicle control. Cell viability was evaluated using Cell Counting Kit-8 (CCK-8) assay. After polyriboinosinic:polyribocytidylic acid (poly(I:C)) stimulus, cells with or without hinokitiol were evaluated for the mRNA and protein levels of interleukin-8 (IL-8), interleukin-6 (IL-6), and interleukin-1β (IL-1β) using real-time PCR analysis and an enzyme-linked immunosorbent assay (ELISA), respectively. Nuclear and cytoplasmic levels of nuclear factor kappa B (NF-κB) p65 protein and an inhibitor of NF-κB α (IκBα) were evaluated using western blotting.Results
There were no significant differences among the treatment concentrations of hinokitiol compared with cells incubated in medium only. Incubating with 100 μM hinokitiol significantly decreased the mRNA levels of IL-8 to 58.77±10.41% (P<0.01), IL-6 to 64.64±12.71% (P<0.01), and IL-1β to 54.19±8.10% (P<0.01) compared with cells stimulated with poly(I:C) alone. The protein levels of IL-8, IL-6, and IL-1β had similar trend. Further analysis revealed that hinokitiol maintained the levels of IκBα and significantly reduced NF-κB p65 subunit translocation to the nucleus which significantly inhibiting the activation of the NF-κB signal pathway.Conclusion
Hinokitiol showed a significant protective effect against ocular surface inflammation through inhibiting the NF-κB pathway, which may indicate the possibility to relieve the ocular surface inflammation of dry eye syndrome (DES). 相似文献998.
L Huang Q Meng C Zhang Y Sun Y Bai S Li X Deng B Wang W Yu M Zhao X Li 《Eye (London, England)》2015,29(5):691-698
Purpose
To evaluate the association and interaction of five single-nucleotide polymorphisms (SNPs) in three genes (CFH, ARMS2, and ARMS2/HTRA1) with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) in Chinese population.Methods
A total of 300 nAMD and 300 PCV patients and 301 normal subjects participated in the present study. The allelic variants of rs800292, rs2274700, rs3750847, rs3793917, and rs1065489 were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Gene–gene interactions were evaluated by the data mining approach multifactor-dimensionality reduction (MDR) method.Results
The risk alleles of CFH rs800292, rs2274700, ARMS2 rs3057847, and ARMS2/HTRA1 rs3793917 showed significant difference between nAMD or PCV patients and controls (all P<0.01). The homozygosity of risk alleles for rs800292, rs2274700, rs3750847, and rs3793917 were significantly different between nAMD patients and controls (all P<0.01), and predisposed to PCV patients (all P<0.01). After cross-validation consistency (CVC) and permutation tests, the two-locus model rs2274700_rs3750847 has a balanced accuracy of 64.37% in predicting nAMD disease risk. The one-marker model, rs3750847, and two-locus model rs2274700_rs3750847 has a balanced accuracy of 66.07% and 65.89% in predicting PCV disease risk, respectively. Furthermore, CFH rs1065489 did not show significant association with nAMD (P>0.01), but was strongly associated with PCV in Chinese patients (P<0.001).Conclusions
In this study, we found that the interaction of ARMS2 and ARMS2/HTRA1 is significantly associated with nAMD, and the interaction of CFH and ARMS2 is pronounced in PCV development in Chinese population. 相似文献999.
Purpose
Observe the image characteristics and dislocation of implantable collamer lenses (ICL) following their use to correct high myopia.Methods
A total of 127 patients (242 eyes); 64 females (50.3%) and 63 males (49.7%) were included in this retrospective study with ICL V4 implantation and mean spherical equivalent −9.08±2.04 diopters (D). Panoramic ultrasound biomicroscopy (UBM) was utilized to observe anterior segment morphology and ICL location at various follow-up periods (1 week preoperative, followed by 1, 3, 6, and yearly postoperative).Results
Twenty-eight ICL eyes (11.2%) were noted to have abnormal postoperative positioning. The central vault of 12 eyes was too high with ICL decentration, mean central vault 1.14±0.39 mm; 10 eyes were too low but without ICL decentration, mean central vault 0.13±0.11 mm. The remaining subjects were only ICL decentration without abnormal central vault, mean central vault was 0.54±0.28 mm.Conclusions
This study shows the abnormal characteristics regarding ICL locations. The ICL dislocation closely correlates with the central vault. The ICL dislocation is the primary cause of several postoperative complications. Panoramic UBM is one of the most effective imaging means to observe the ICL positioning and its stability after implantable surgery. 相似文献1000.
Fan Zhang Yufeng Hu Zhidong Lou Xige Xin Meng Zhang Yanbing Hou Feng Teng 《RSC advances》2018,8(21):11272
The properties of semiconductor/dielectric interfaces are crucial to the performance of polymer field-effect transistors. The key to fabricating high-performance polymer transistors by spin-coating is solving solvent corrosion issues, wherein the solvent of the top polymer produces a rough interface or damage on the underlying polymer layer during deposition. Herein, we propose a mixed-solvent method that employs a mixture of an orthogonal solvent of the underlying polymer and a good solvent of the top polymer as the solvent of the top polymer to prepare polymer bilayers and produce a comparative study of the trap density at the semiconductor/dielectric interface of the corresponding transistor. By changing the ratio of orthogonal solvent to good solvent, namely the degree of orthogonality of the mixed solvent with respect to the underlying polymer, the interface and film qualities of polymer bilayers can be well controlled. We applied this method to spin-coat poly(3-hexylthiophene) (P3HT) on poly(methylmethacrylate) (PMMA) with a mixture of cyclohexane (orthogonal solvent) and chloroform (good solvent). The results of morphology characterizations and electrical property studies indicate the optimal ratio of cyclohexane to chloroform for preparing high-quality P3HT/PMMA bilayers for field-effect conduction is 7 : 3. Transistors based on the optimal bilayers with a bottom-gate/top-contact configuration and a long channel length show good performance. The trap density at the P3HT/PMMA interface is evaluated to be 3.6 × 1012 cm−2 eV−1 from the subthreshold swing, characterizing the distribution of the interface trap levels across the bandgap in P3HT. Furthermore, based on deviations from ideality in the capacitance–voltage characteristics of the metal–insulator–semiconductor capacitor in the device, the traps at the interface are found to be acceptor-type, with the trap density determined to be 2.3 × 1011 cm−2. This value is in a good agreement with that estimated from the subthreshold swing.A mixture of an orthogonal solvent of the bottom polymer and a good solvent of the top polymer is used as the solvent of the top layer to prepare polymer bilayers. The trap densities at the semiconductor/dielectric interface of the corresponding transistor are evaluated. 相似文献