全文获取类型
收费全文 | 43931篇 |
免费 | 2218篇 |
国内免费 | 139篇 |
专业分类
耳鼻咽喉 | 621篇 |
儿科学 | 1762篇 |
妇产科学 | 718篇 |
基础医学 | 5812篇 |
口腔科学 | 1016篇 |
临床医学 | 2830篇 |
内科学 | 10932篇 |
皮肤病学 | 1538篇 |
神经病学 | 3566篇 |
特种医学 | 1320篇 |
外科学 | 5968篇 |
综合类 | 275篇 |
一般理论 | 15篇 |
预防医学 | 3769篇 |
眼科学 | 1189篇 |
药学 | 2577篇 |
3篇 | |
中国医学 | 196篇 |
肿瘤学 | 2181篇 |
出版年
2024年 | 117篇 |
2023年 | 324篇 |
2022年 | 305篇 |
2021年 | 1188篇 |
2020年 | 551篇 |
2019年 | 1244篇 |
2018年 | 1926篇 |
2017年 | 1107篇 |
2016年 | 933篇 |
2015年 | 829篇 |
2014年 | 1021篇 |
2013年 | 1770篇 |
2012年 | 3121篇 |
2011年 | 3480篇 |
2010年 | 1713篇 |
2009年 | 1071篇 |
2008年 | 2729篇 |
2007年 | 2834篇 |
2006年 | 2563篇 |
2005年 | 2654篇 |
2004年 | 2444篇 |
2003年 | 2397篇 |
2002年 | 2156篇 |
2001年 | 1573篇 |
2000年 | 1995篇 |
1999年 | 1114篇 |
1998年 | 348篇 |
1997年 | 239篇 |
1996年 | 216篇 |
1995年 | 216篇 |
1994年 | 157篇 |
1993年 | 143篇 |
1992年 | 176篇 |
1991年 | 162篇 |
1990年 | 126篇 |
1989年 | 151篇 |
1988年 | 129篇 |
1987年 | 118篇 |
1986年 | 119篇 |
1985年 | 123篇 |
1984年 | 93篇 |
1983年 | 71篇 |
1982年 | 68篇 |
1981年 | 44篇 |
1980年 | 57篇 |
1979年 | 34篇 |
1978年 | 35篇 |
1977年 | 47篇 |
1976年 | 38篇 |
1975年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 34 毫秒
21.
Alberto Talaya Estela Giménez José Luis Piñana Eliseo Albert Juan Carlos Hernández-Boluda Ariadna Pérez Ignacio Torres Carlos Solano David Navarro 《Journal of medical virology》2019,91(6):1128-1135
It has been reported that low-plasma cytomegalovirus (CMV) DNA loads are associated with an increased risk of overall mortality in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Utilizing a conservative strategy for initiation of preemptive antiviral therapy (>1500 IU/mL), we characterized the virological features of spontaneously-resolving episodes of CMV DNAemia and assessed their impact on mortality through the first year after transplantation. We reviewed the CMV DNA polymerase chain reaction results and clinical charts of 230 consecutive adult patients who underwent T-cell replete allo-HSCT at our center. A total of 280 episodes of CMV DNAemia were registered in 164 patients, of which 144 episodes cleared spontaneously. Clearance of CMV DNAemia was significantly delayed in initial and recurrent self-resolving episodes featuring CMV DNA peak loads > 250 IU/mL compared with those displaying lower values. All-cause mortality in patients with self-resolving episodes of CMV DNAemia was comparable (P = 0.7) to that in patients with no CMV DNAemia and was not related to the CMV DNA peak load (≥250 IU/mL vs <250 IU/mL) (P = 0.6). In summary, in our setting, the magnitude of the CMV DNA peak load reached during self-resolving episodes of CMV DNAemia correlated directly with duration of episodes, but had no apparent impact on all-cause mortality taking patients with no documented CMV DNAemia as a reference. 相似文献
22.
23.
Luz Hermes R. Muñoz-Leal Sebastián de Carvalho William D. Castro Isaí J. Xavier Bruna S. Toledo José J. Hilário Renato Acosta Igor C. L. Faccini João Luiz H. Labruna Marcelo B. 《Parasitology research》2019,118(11):3185-3189
A total of 482 bats representing 32 species and two families were captured in the Amazon forests of the Amapá state in northern Brazil. Nineteen Artibeus planirostris bats (3.9 %) were infested with 160 ticks, all identified as Ornithodoros hasei. Three pools of larvae were screened for rickettsial DNA via polymerase chain reaction (PCR) targeting three rickettsial genes: gltA, ompA and htrA. Only one of them yielded an amplicons of the expected size for all three molecular assays. Comparisons of the obtained sequences including a phylogenetic analysis confirmed the occurrence of “Candidatus Rickettsia wissemanii” in Brazil.
相似文献24.
Araya Paulina Romero Jacqueline Delgado-López Fernando Gonzalez Ileana Añazco Carolina Perez Ramón Rojas Armando 《Inflammation research》2019,68(8):639-642
Inflammation Research - The hypoxic milieu at tumor microenvironment is able to drive the behavior of infiltrating tumor cells. Considering that hypoxia-mediated HMGB1 release is known to promote... 相似文献
25.
Mariángeles González-Fernández Elena Villamañán Inmaculada Jiménez-Nácher Francisco Moreno Chamaida Plasencia Francisco Gaya Alicia Herrero Alejandro Balsa 《International journal of clinical pharmacy》2018,40(6):1528-1538
Background Spending on biological agents has risen dramatically due to the high cost of the drugs and the increased prevalence of spondyloarthritis. Objective To evaluate the annual cost per patient and cost for each biological drug for treating patients with spondyloarthritis from 2009 to 2016, and to calculate factors that affect treatment cost, such as optimizing therapies by monitoring drug serum levels, the use of biosimilar-TNF inhibitors, and official discounts or negotiated rebates in biologicals acquired by the pharmacy department. Method Retrospective, observational study in a Spanish tertiary hospital. Main outcome Annual cost per patient and per drug. Factors that influenced the costs and socio-demographic parameters and disease activity. Results A total of 129, 215, and 224 patients were treated in 2009, 2013, and 2016, respectively. The annual cost per patient decreased: EUR11,604 in 2009, EUR8513 in 2013, and EUR7464 in 2016. The introduction of new drugs drives economic competition, leading to total savings per drug, with discounts reaching 5.8, 12.4, 16.7, 17.7, 13.7, and 24.8% for original infliximab, etanercept, adalimumab, ertolizumab, golimumab, and secukinumab, respectively, while rebates for biosimilar infliximab reached 31.90% in 2016. The number of patients with optimized therapies reached 47.5% in 2016, which led to cost savings of EUR798,614, in addition to savings from official discounts and rebates of EUR252,706 and savings from optimized therapies of EUR545,908 in 2016. Conclusion The cost of biological treatments declined after official discounts, negotiated rebates, and optimized therapies, leading to a significant decrease in the annual cost per patient. The greatest contribution to economic savings in biological therapy according to our study was biological therapy optimization. 相似文献
26.
27.
Lorena S. Pacheco David A. Hernández-Ontiveros Esmeralda Iniguez-Stevens Stephanie Brodine Richard S. Garfein Margarita Santibañez Miguel A. Fraga 《BMC public health》2018,18(1):1397
Background
Diabetes is a leading cause of morbidity and mortality in Mexico and understudied among indigenous populations. This study aimed to determine the prevalence and identify correlates of Type 2 diabetes mellitus (Type 2 DM) and metabolic syndrome (MetS) in a rural, indigenous community in Northwestern Mexico.Methods
A cross-sectional study was conducted in the community of San Quintin, Baja California, Mexico, among a sample of households. A total of 275 participants (≥18?years old) underwent a questionnaire, physical examination, and serologic test. Prevalence and adjusted odds ratio (AOR), using logistic regression modeling, were estimated with 95% confidence intervals (95% CI).Results
The prevalence of Type 2 DM and MetS was 21.8 and 53.1%, respectively. Mean?±?standard deviation (SD) age and body mass index of study participants was 35.8?±?13.0?years and 28.7?±?5.6?kg/m2, respectively. Participants were 75% female and 60.7% self-identified as indigenous. Thirty-seven percent of adults had high blood pressure. After controlling for age, higher educational attainment had a protective effect on Type 2 DM (AOR?=?0.39; 95% CI 0.20, 0.77). Additionally, the presence of MetS was associated with being female (AOR?=?2.27; 95% CI 1.23, 4.14) and having lower educational attainment (AOR?=?0.62; 95% CI 0.37, 0.94).Conclusions
The prevalence of Type 2 DM and MetS was high in this rural and indigenous population, and education was shown to play a critical role. These findings support the need for community-inclusive health-promoting interventions in rural communities.28.
González-García R Gil-Díez Usandizaga JL Hyun Nam S Rodríguez Campo FJ Naval-Gías L 《The British journal of oral & maxillofacial surgery》2006,44(6):543-545
We operated on a 65-year-old woman and removed a solitary fibrous tumour from her oral mucosa. Microscopically we found marked atypia, abundant necrosis, increased number of mitotic figures (>4 in 10 high-power fields) and hypercellularity. The tumour cells were strongly stained for CD34. There has been no recurrence after 18 months. 相似文献
29.
Noguerol B Muñoz R Mesa F de Dios Luna J O'Valle F 《Clinical oral implants research》2006,17(4):459-464
Objectives: The objectives of this study were to determine the accuracy of Periotest® to monitor primary implant stability at first‐stage surgery, to identify by multivariate analysis the variables associated with early implant failure and to compare Periotest® with radiographic study in the diagnosis of implant stability at second‐stage surgery (during osseointegration period). Material and methods: A 10‐year retrospective study was conducted on 1084 Brånemark® implants placed in 316 patients. Clinical variables, implant diameter and length, Periotest® values (PTVs) and radiological variables were analyzed in bivariate and multivariate studies in order to determine their influence on early implant failure. Results: After examination of the sensitivity and specificity values obtained for different PTV cutoff points, a cutoff PTV of ?2 was selected (84% sensitivity and 39% specificity). In the bivariate analysis, early failure was significantly related to smoking habits, implant location, bone type, implant features and PTVs (?2 and ≥?2). In the final multiple logistic model, only age (odds ratio (OR)=4.53; 95% confidence interval (CI), 1.34–15.27), smoking habits (OR=2.5; 95% CI, 1.3–4.79), bone type (OR=1.93; 95% CI, 1.01–3.7) and PTV at first surgery (OR=3.01; 95% CI, 1.5–6.02) were independently related to early failure. Conclusions: The Periotest® (with ?2 cutoff) at first surgery offers high sensitivity in the prognosis of early implant loss and shows a greater capacity to evaluate stability during the osseointegration period compared with radiographic study. 相似文献
30.