全文获取类型
收费全文 | 121803篇 |
免费 | 7469篇 |
国内免费 | 711篇 |
专业分类
耳鼻咽喉 | 1304篇 |
儿科学 | 4061篇 |
妇产科学 | 2897篇 |
基础医学 | 17222篇 |
口腔科学 | 4155篇 |
临床医学 | 11268篇 |
内科学 | 27477篇 |
皮肤病学 | 3180篇 |
神经病学 | 11685篇 |
特种医学 | 2990篇 |
外国民族医学 | 1篇 |
外科学 | 11998篇 |
综合类 | 580篇 |
一般理论 | 68篇 |
预防医学 | 11663篇 |
眼科学 | 2055篇 |
药学 | 8413篇 |
中国医学 | 447篇 |
肿瘤学 | 8519篇 |
出版年
2024年 | 135篇 |
2023年 | 1143篇 |
2022年 | 2424篇 |
2021年 | 4218篇 |
2020年 | 2619篇 |
2019年 | 3513篇 |
2018年 | 3996篇 |
2017年 | 3026篇 |
2016年 | 3511篇 |
2015年 | 3831篇 |
2014年 | 5037篇 |
2013年 | 6591篇 |
2012年 | 9961篇 |
2011年 | 10343篇 |
2010年 | 5632篇 |
2009年 | 4795篇 |
2008年 | 8194篇 |
2007年 | 8281篇 |
2006年 | 7593篇 |
2005年 | 7093篇 |
2004年 | 6399篇 |
2003年 | 5669篇 |
2002年 | 5082篇 |
2001年 | 755篇 |
2000年 | 570篇 |
1999年 | 787篇 |
1998年 | 922篇 |
1997年 | 729篇 |
1996年 | 622篇 |
1995年 | 513篇 |
1994年 | 497篇 |
1993年 | 424篇 |
1992年 | 403篇 |
1991年 | 318篇 |
1990年 | 302篇 |
1989年 | 296篇 |
1988年 | 276篇 |
1987年 | 247篇 |
1986年 | 271篇 |
1985年 | 219篇 |
1984年 | 234篇 |
1983年 | 212篇 |
1982年 | 237篇 |
1981年 | 217篇 |
1980年 | 193篇 |
1979年 | 155篇 |
1978年 | 150篇 |
1977年 | 135篇 |
1976年 | 103篇 |
1974年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Camargo Carlos Henrique de Souza da Cunha Maria de Lourdes Ribeiro Caramori Jacqueline Costa Teixeira Mondelli Alessandro Lia Montelli Augusto Cezar Barretti Pasqual 《International urology and nephrology》2021,53(2):381-381
International Urology and Nephrology - In the original publication, article title was incorrectly published. 相似文献
972.
Cannizzaro Delia Tropeano Maria Pia Milani Davide Spaggiari Riccardo Zaed Ismail Mancarella Cristina Lasio Giovanni Battista Fornari Maurizio Servadei Franco Cardia Andrea 《Neurosurgical review》2021,44(3):1217-1225
Neurosurgical Review - Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5... 相似文献
973.
Belotti Francesco Tengattini Francesco Mattavelli Davide Ferrari Marco Fiorentino Antonio Agnelli Silvia Schreiber Alberto Nicolai Piero Fontanella Marco Maria Doglietto Francesco 《Neurosurgical review》2021,44(1):279-287
Neurosurgical Review - Recently, endoscopic transsphenoidal transclival approaches have been developed and their role is widely accepted for extradural pathologies. Their application to intradural... 相似文献
974.
Projected Economic Burden of Periprosthetic Joint Infection of the Hip and Knee in the United States
Ajay Premkumar David A. Kolin Kevin X. Farley Jacob M. Wilson Alexander S. McLawhorn Michael B. Cross Peter K. Sculco 《The Journal of arthroplasty》2021,36(5):1484-1489.e3
BackgroundIn addition to the significant morbidity and mortality associated with periprosthetic joint infection (PJI), the cost of treating PJI is substantial. Prior high-quality national estimates of the economic burden of PJI utilize data up to 2009 to project PJI growth in the United States through 2020. Now in the year 2020, it is appropriate to evaluate these past projections and incorporate the latest available data to better understand the current scale and burden of PJI in the United States.MethodsThe Nationwide Inpatient Sample (2002-2017) was used to identify rates and associated inpatient costs for primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) and PJI-related revision TKA and THA. Poisson regression was utilized to model past growth and project future rates and cost of PJI of the hip and knee.ResultsUsing the most recent data, the combined annual hospital costs related to PJI of the hip and knee were estimated to be $1.85 billion by 2030. This includes $753.4 million for THA PJI and $1.1 billion for TKA PJI, in that year. Increases in PJI costs are mainly attributable to increases in volume. Although the growth in incidence of primary THA and TKA has slowed in recent years, the incidence of PJI and the cost per case of PJI remained relatively constant from 2002 to 2017.DiscussionUnderstanding the current and potential future financial burden of PJI for surgeons, patients, and healthcare systems is essential. There is an urgent need for efficacious preventive strategies in reducing rates of PJI after THA and TKA. 相似文献
975.
Mark F. Zhu Katy Kim Alana Cavadino Brendan Coleman Jacob T. Munro Simon W. Young 《The Journal of arthroplasty》2021,36(1):305-310.e1
BackgroundProsthetic joint infection (PJI) is the most common cause of failure following total knee arthroplasty (TKA). This study aimed to determine the success of debridement, antibiotics, and implant retention (DAIR) in a large cohort of TKA PJIs and assess the utility of current classification systems in predicting DAIR outcomes in early postoperative, late hematogenous, and chronic PJIs.MethodsIn a multicenter review over 15 years, 230 patients underwent DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors, treatment regime, and outcomes were identified. Univariate and multivariate survival analyses were performed to identify factors associated with successful DAIR. Continuous variables with predictive value were further analyzed using receiver operating characteristic curves. The ability to predict DAIR outcomes of multiple classification systems was also assessed.ResultsPatients were followed for an average of 6.9 years. The overall success rate of DAIR was 53.9%. On receiver operating characteristic analysis, 3 months (area under the curve = 0.63) and 1-year age (area under the curve = 0.66) of implant cut-offs was similarly predictive of outcomes. On multivariate survival analysis, DAIR was successful in 64% of “early” PJIs (implant <1 year) vs 38% of “late hematogenous” PJIs (implant >1 year; odds ratio [OR] 1.78, P = .01). For late PJIs (implant >1 year), Staphylococcus aureus (OR 4.70, P < .001) and gram-negative infections (OR 2.56, P = .031) were risk factors for DAIR failure.ConclusionDAIR has a high failure rate in all PJIs occurring more than a year post primary TKA, particularly when caused by S aureus or gram-negative bacteria. The age of implant is an important predictor of DAIR outcomes. 相似文献
976.
McKayla E. Kelly Justin J. Turcotte Jacob M. Aja James H. MacDonald Paul J. King 《The Journal of arthroplasty》2021,36(3):1009-1012
BackgroundDexamethasone has been shown to reduce postoperative pain and opioid consumption for total joint arthroplasty patients; however, its impact on patients who received neuraxial anesthesia (NA) is not well described. We examined the impact of perioperative dexamethasone on outcomes for patients undergoing direct anterior approach total hip arthroplasty (THA) under NA.MethodsA retrospective review was conducted for 376 THA patients from a single institution. Univariate analysis was used to compare postoperative outcomes for 164 THA patients receiving dexamethasone compared to 212 who did not receive dexamethasone.ResultsNo differences in age, gender, body mass index, or American Society of Anesthesiologists (ASA) Score were observed between the groups. Patients receiving perioperative dexamethasone reported statistically significantly lower postanesthesia care unit (PACU) pain numeric rating scale (Dexamethasone 1.6 vs No dexamethasone 2.3, P = .014) and received lower PACU morphine milligram equivalents (MME) (Dexamethasone 8.57 vs No dexamethasone 11.44, P < .001). Patients receiving dexamethasone had significantly shorter LOS (Dexamethasone 29.40 vs No dexamethasone 35.26 hrs., P < .001).ConclusionPerioperative dexamethasone is associated with decreased postoperative pain and narcotic consumption, and shorter length of stay for patients undergoing primary direct anterior approach THA with NA. 相似文献
977.
Luigi Gennari Daniela Merlotti Natale Figura Christian Mingiano Maria Beatrice Franci Barbara Lucani Tommaso Picchioni Mario Alessandri Maria Stella Campagna Sara Gonnelli Simone Bianciardi Maria Materozzi Carla Caffarelli Stefano Gonnelli Ranuccio Nuti 《Journal of bone and mineral research》2021,36(1):80-89
Helicobacter pylori (HP) infection is a common and persistent disorder acting as a major cofactor for the development of upper gastrointestinal diseases and several extraintestinal disorders including osteoporosis. However, no prospective study assessed the effects of HP on bone health and fracture risk. We performed a HP screening in a population-based cohort of 1149 adults followed prospectively for up to 11 years. The presence of HP infection was assessed by serologic testing for serum antibodies to HP and the cytotoxin associated gene-A (CagA). The prevalence of HP infection did not differ among individuals with normal bone mineral density (BMD), osteoporosis, and osteopenia. However, HP infection by CagA-positive strains was significantly increased in osteoporotic (30%) and osteopenic (26%) patients respect to subjects with normal BMD (21%). Moreover, anti-CagA antibody levels were significantly and negatively associated with lumbar and femoral BMD. Consistent with these associations, patients affected by CagA-positive strains had a more than fivefold increased risk to sustain a clinical vertebral fracture (HR 5.27; 95% CI, 2.23–12.63; p < .0001) and a double risk to sustain a nonvertebral incident fracture (HR 2.09; 95% CI, 1.27–2.46; p < .005). Reduced estrogen and ghrelin levels, together with an impaired bone turnover balance after the meal were also observed in carriers of CagA-positive HP infection. HP infection by strains expressing CagA may be considered a risk factor for osteoporosis and fractures. Further studies are required to clarify in more detail the underlying pathogenetic mechanisms of this association. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献
978.
Marysol Luna Jason D Guss Laura S Vasquez-Bolanos Macy Castaneda Manuela Vargas Rojas Jasmin M Strong Denise A Alabi Sophie D Dornevil Jacob C Nixon Erik A Taylor Eve Donnelly Xueyan Fu M Kyla Shea Sarah L Booth Rodrigo Bicalho Christopher J Hernandez 《Journal of bone and mineral research》2021,36(9):1823-1834
Modifications to the constituents of the gut microbiome influence bone density and tissue-level strength, but the specific microbial components that influence tissue-level strength in bone are not known. Here, we selectively modify constituents of the gut microbiota using narrow-spectrum antibiotics to identify components of the microbiome associated with changes in bone mechanical and material properties. Male C57BL/6J mice (4 weeks) were divided into seven groups (n = 7–10/group) and had taxa within the gut microbiome removed through dosing with: (i) ampicillin; (ii) neomycin; (iii) vancomycin; (iv) metronidazole; (v) a cocktail of all four antibiotics together (with zero-calorie sweetener to ensure intake); (vi) zero-calorie sweetener only; or (vii) no additive (untreated) for 12 weeks. Individual antibiotics remove only some taxa from the gut, while the cocktail of all four removes almost all microbes. After accounting for differences in geometry, whole bone strength was reduced in animals with gut microbiome modified by neomycin (−28%, p = 0.002) and was increased in the group in which the gut microbiome was altered by sweetener alone (+39%, p < 0.001). Analysis of the fecal microbiota detected seven lower-ranked taxa differentially abundant in animals with impaired tissue-level strength and 14 differentially abundant taxa associated with increased tissue-level strength. Histological and serum markers of bone turnover and trabecular bone volume per tissue volume (BV/TV) did not differ among groups. These findings demonstrate that modifications to the taxonomic components of the gut microbiome have the potential to decrease or increase tissue-level strength of bone independent of bone quantity and without noticeable changes in bone turnover. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
979.
Leonore Ingold Jörg Halter Maria Martinez Patrizia Amico Caroline Wehmeier Patricia Hirt-Minkowski Jürg Steiger Michael Dickenmann Stefan Schaub 《Transplant international》2021,34(10):1875-1885
The aim of this retrospective single-center study was to investigate the short- and long-term impact of neutropenia occurring within the first year after kidney transplantation, with a special emphasis on different neutropenia grades. In this unselected cohort, 225/721 patients (31%) developed 357 neutropenic episodes within the first year post-transplant. Based on the nadir neutrophil count, patients were grouped as neutropenia grade 2 (<1.5–1.0*109/l; n = 105), grade 3 (<1.0–0.5*109/l; n = 65), and grade 4 (<0.5*109/l; n = 55). Most neutropenia episodes were presumably drug-related (71%) and managed by reduction/discontinuation of potentially responsible drugs (mycophenolic acid [MPA] 51%, valganciclovir 25%, trimethoprim/sulfamethoxazole 19%). Steroids were added/increased as replacement for reduced/discontinued MPA. Granulocyte colony-stimulating factor was only used in 2/357 neutropenia episodes (0.6%). One-year incidence of (sub)clinical rejection, one-year mortality, and long-term patient and graft survival were not different among patients without neutropenia and neutropenia grade 2/3/4. However, the incidence of infections was about 3-times higher during neutropenia grade 3 and 4, but not increased during grade 2. In conclusion, neutropenia within the first year after kidney transplantation represents no increased risk for rejection and has no negative impact on long-term patient and graft survival. Adding/increasing steroids as replacement for reduced/discontinued MPA might supplement management of neutropenia. 相似文献
980.
Gabriel Stefan Ana Maria Mehedinti Iuliana Andreiana Adrian Dorin Zugravu Simona Cinca Ruxandra Busuioc Ioana Miler Simona Stancu Ligia Petrescu Ioana Dimitriu Elena Moldovanu Diana Elena Crasnaru Georgeta Gugonea Valentin Georgescu Victor Dan Strambu Cristina Capusa 《Renal failure》2021,43(1):49
Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis. 相似文献