全文获取类型
收费全文 | 36397篇 |
免费 | 2664篇 |
国内免费 | 514篇 |
专业分类
耳鼻咽喉 | 246篇 |
儿科学 | 485篇 |
妇产科学 | 466篇 |
基础医学 | 1816篇 |
口腔科学 | 268篇 |
临床医学 | 3155篇 |
内科学 | 4240篇 |
皮肤病学 | 522篇 |
神经病学 | 1371篇 |
特种医学 | 563篇 |
外国民族医学 | 1篇 |
外科学 | 2161篇 |
综合类 | 4046篇 |
预防医学 | 5807篇 |
眼科学 | 232篇 |
药学 | 11011篇 |
14篇 | |
中国医学 | 630篇 |
肿瘤学 | 2541篇 |
出版年
2023年 | 447篇 |
2022年 | 893篇 |
2021年 | 1206篇 |
2020年 | 1139篇 |
2019年 | 1175篇 |
2018年 | 1177篇 |
2017年 | 1143篇 |
2016年 | 1103篇 |
2015年 | 1266篇 |
2014年 | 2653篇 |
2013年 | 3244篇 |
2012年 | 2557篇 |
2011年 | 2904篇 |
2010年 | 2128篇 |
2009年 | 1993篇 |
2008年 | 2000篇 |
2007年 | 1897篇 |
2006年 | 1600篇 |
2005年 | 1323篇 |
2004年 | 1092篇 |
2003年 | 894篇 |
2002年 | 711篇 |
2001年 | 628篇 |
2000年 | 532篇 |
1999年 | 517篇 |
1998年 | 339篇 |
1997年 | 305篇 |
1996年 | 259篇 |
1995年 | 241篇 |
1994年 | 229篇 |
1993年 | 187篇 |
1992年 | 164篇 |
1991年 | 122篇 |
1990年 | 122篇 |
1989年 | 98篇 |
1988年 | 112篇 |
1987年 | 105篇 |
1986年 | 101篇 |
1985年 | 114篇 |
1984年 | 135篇 |
1983年 | 69篇 |
1982年 | 77篇 |
1981年 | 53篇 |
1980年 | 68篇 |
1979年 | 51篇 |
1978年 | 57篇 |
1977年 | 52篇 |
1976年 | 60篇 |
1975年 | 65篇 |
1974年 | 43篇 |
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
61.
The incidence of spontaneous pregnancy/infant losses is highly variable in long-tailed macaques (cynomolgus monkey), making it potentially difficult to ascertain test item-related effects in developmental toxicity studies. Therefore, pregnancy normograms had been developed by Jarvis et al. [1] to aid in the distinction of normal (e.g. test facility background) versus non-normal pregnancy outcomes. These normograms were mostly derived from embryo-fetal development studies and from PPND studies with a postnatal phase limited to seven days. However, the enhanced pre- and postnatal developmental (ePPND) study paradigm has essentially replaced these former study types. This work aims at providing enhanced normograms (e-normograms) in the context of regulatory ePPND studies. Survival functions for the prenatal phase (286 control pregnancies) and the postnatal phase (222 live infants) were estimated using the Kaplan-Meier estimator. Normograms were generated from survival curves and pseudo-study simulations. Data were available from two test facilities with comparable EU-compliant animal husbandry. Pregnancy duration/outcome as well as survival functions did not differ significantly between test facilities indicating that this husbandry system yields comparable developmental observations across different test facilities, at least in this NHP species. These novel e-normograms were developed for pregnant long-tailed macaques and provide an extended postnatal period up to three months, a new concept of separate normograms for the prenatal and the postnatal period, specific information on the perinatal phase events, a prediction of expected number of live infants for group size management, and the option to evaluate effects on pregnancy duration through distinction of live births and infant losses. 相似文献
62.
63.
本文在梳理英国医保药品报销政策的基础上,通过对价值定价理念的深入研究和理解,系统探讨其在报销政策制定过程中对药品目录遴选、价值测算、支付标准确定、医保基金平衡和报销效益评估的作用机制,并深入思考通过价值定价理念建立起的药物警戒体系与药品报销政策间的衔接机制。在此基础上总结价值定价理念的特点、应用阶段和具体操作方法,以期为我国提供借鉴。 相似文献
64.
Mohammad Kogani Seyed Ahmad Almasi Alireza Ansari-Mogaddam Sahar Dalvan Hassan Okati-Aliaba Seyed Mehdi Tabatabaee Seyedeh Zeinab Almasi 《中华创伤杂志(英文版)》2020,23(6):319-323
Purpose: Traffic accidents are one of the major health problems in the world, being the first cause of burden of illness and the second leading cause of death in Iran. The Sistan-Baluchestan province is one of the most accidental provinces of Iran with the highest rate of accidents-caused deaths. This study was conducted to determine the risk factors associated with traffic accidents in Zahedan through 2013 to 2016.
Methods: This analytical cross-sectional study was carried out on 223 drivers from Zahedan who were traumatized by traffic accident and sent to Zahedan hospitals. The data were obtained through interviews taken by the trained interviewers via refereeing to the medical records and collected in the researcher-made checklist. Census was obtained from the study subjects. For data analysis, independent t-test, one-way ANOVA, Chi-square and logistic regression were used with the Stata software version 11.0.
Results: In this study, 223 male subjects with the mean age of (32.54 ± 12.95) years, 39.8% single and 60.2% married, entered for investigation. Most accidents (38.8%) occurred between 12:00 to 17:59. While driving, 47.1% of the study subjects were using cell phones, 89.1% had manual use of mobile phones, 21.9% had a habit of sending short message service (SMS) and 23.4% had sent SMS within 10 min before the accident. The one way analysis of variance showed that the mean age of individuals with marital status, driving experience, education and accident with motorcycle were significantly different (p < 0.05). Also, the multivariate logistic regression test indicated a significant relationship of smoking, ethnicity, insurance and SMS typing while driving with motorcycle accident (p < 0.05).
Conclusion: In this study, SMS and smoking while driving had the highest risk among the variables studied in the motorcycle accidents. Therefore, effective education attempting to enhance people''s awareness about the consequences of using cell phone and smoking during driving to reduce traffic accidents seems necessary. 相似文献
65.
《Best Practice & Research: Clinical Rheumatology》2022,36(4):101810
Osteoarthritis (OA) is a highly prevalent joint disease that is associated with pain, loss of function, and high direct and indirect economic costs. The current therapeutic options are inadequate, providing only a moderate symptom relief without the possibility of disease modification. While treatment options and personalized medicines are increasing for many complex diseases, OA drug development has been impeded by the advanced state of disease at the time of diagnosis and intervention, heterogeneity in both symptoms and rates of progression, and a lack of validated biomarkers and relevant outcome measures. This review article summarizes the OA landscape, including therapies in development as potential OA treatments, potential biomarkers undergoing evaluation by the US Food and Drug Administration, and a summary of current OA treatment guidelines, with a particular focus on the knee OA. 相似文献
66.
《Health policy (Amsterdam, Netherlands)》2020,124(3):231-238
BackgroundBecause not all medicines are equally safe, effective, and affordable, health systems often use formularies to define explicitly which medicines will be included and excluded from coverage.ObjectiveWe sought to synthesize methods and findings from published studies of formulary variation across health systems in high-income countries.MethodsWe conducted a systematic review of peer-reviewed research papers published from 2000 to 2017, inclusively. Because of the heterogeneous nature of the literature, we used an inductive approach to summarize methods and findings.ResultsNine studies met our study inclusion criteria. Included studies used a variety of methods for selecting medicines for analysis, for measuring coverage levels, and for measuring concordance between formularies. Studies assessing variations in coverage of all licensed medicines and found lower rates of cross-national coverage variation than studies of coverage for selected specialty drugs and indications. The one study that focused on coverage of high-volume medicines found the most complete and consistent levels of formulary listings across countries.ConclusionAlthough published studies contain interesting findings that likely have prompted discussions about their policy implications, the literature can be improved with greater transparency concerning the overarching objective of work in this area and more rigor concerning the selection, analysis, and reporting of data. 相似文献
67.
68.
Elena Andreucci Anna Laurenzana Silvia Peppicelli Alessio Biagioni Francesca Margheri Jessica Ruzzolini Francesca Bianchini Gabriella Fibbi Mario Del Rosso Chiara Nediani Simona Serratì Livia Fucci Michele Guida Lido Calorini 《Oncology research》2020,28(9):873-884
Malignant melanoma is a highly aggressive skin cancer characterized by an elevated grade of tumor cell plasticity. Such plasticity allows adaptation of melanoma cells to different hostile conditions and guarantees tumor
survival and disease progression, including aggressive features such as drug resistance. Indeed, almost 50% of
melanoma rapidly develop resistance to the BRAFV600E inhibitor vemurafenib, with fast tumor dissemination,
a devastating consequence for patients’ outcomes. Vasculogenic mimicry (VM), the ability of cancer cells to
organize themselves in perfused vascular-like channels, might sustain tumor spread by providing vemurafenibresistant cancer cells with supplementary ways to enter into circulation and disseminate. Thus, this research
aims to determine if vemurafenib resistance goes with the acquisition of VM ability by aggressive melanoma
cells, and identify a driving molecule for both vemurafenib resistance and VM. We used two independent
experimental models of drug-resistant melanoma cells, the first one represented by a chronic adaptation of
melanoma cells to extracellular acidosis, known to drive a particularly aggressive and vemurafenib-resistant
phenotype, the second one generated with chronic vemurafenib exposure. By performing in vitro tube formation assay and evaluating the expression levels of the VM markers EphA2 and VE-cadherin by Western blotting
and flow cytometer analyses, we demonstrated that vemurafenib-resistant cells obtained by both models are
characterized by an increased ability to perform VM. Moreover, by exploiting the CRISPR-Cas9 technique and
using the urokinase plasminogen activator receptor (uPAR) inhibitor M25, we identified uPAR as a driver of
VM expressed by vemurafenib-resistant melanoma cells. Thus, uPAR targeting may be successfully leveraged
as a new complementary therapy to inhibit VM in drug-resistant melanoma patients, to counteract the rapid
progression and dissemination of the disease. 相似文献
69.
《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy. 相似文献
70.
目的:为控制我国药品费用的不合理增长和促进医疗机构药学服务提供参考。方法:分析美国卫生系统药师协会制定的药品成本管理策略,对比我国医疗机构卫生现状,从而提出完善医疗机构药学工作,进行药品控费的建议。结果:美国药品成本管理策略建议医疗机构基于往年采购量(或金额)和使用量(或金额)开展药品预算管理;规范临床药师素质及临床药学服务质量的同时常态化开展交互治疗;成立药师参与临床治疗且获取医务人员支持的治疗小组;制定药品处方集并将成本较低、效果明显的药品纳入电子处方管理系统;建立药品使用替换制度,严格规范药品替换流程。结论:我国医疗机构可以开展药品预算研究来控制药品使用金额;通过提升临床药师技能来增强药师职业认知;加强药师医师沟通以明确两者职能分工;注重药师处方集制定并管控药品不合理使用;完善药品替换制度来规范药品使用管理。 相似文献