全文获取类型
收费全文 | 115621篇 |
免费 | 47408篇 |
国内免费 | 189篇 |
专业分类
耳鼻咽喉 | 1935篇 |
儿科学 | 5473篇 |
妇产科学 | 1469篇 |
基础医学 | 20419篇 |
口腔科学 | 5770篇 |
临床医学 | 17812篇 |
内科学 | 31635篇 |
皮肤病学 | 8209篇 |
神经病学 | 17465篇 |
特种医学 | 3550篇 |
外国民族医学 | 6篇 |
外科学 | 20283篇 |
综合类 | 435篇 |
一般理论 | 65篇 |
预防医学 | 8058篇 |
眼科学 | 1954篇 |
药学 | 7846篇 |
1篇 | |
中国医学 | 1082篇 |
肿瘤学 | 9751篇 |
出版年
2023年 | 314篇 |
2022年 | 242篇 |
2021年 | 1983篇 |
2020年 | 5611篇 |
2019年 | 11483篇 |
2018年 | 11049篇 |
2017年 | 12152篇 |
2016年 | 12777篇 |
2015年 | 12793篇 |
2014年 | 13034篇 |
2013年 | 14221篇 |
2012年 | 6619篇 |
2011年 | 6841篇 |
2010年 | 10548篇 |
2009年 | 6892篇 |
2008年 | 4591篇 |
2007年 | 3633篇 |
2006年 | 3656篇 |
2005年 | 3466篇 |
2004年 | 3401篇 |
2003年 | 3328篇 |
2002年 | 3300篇 |
2001年 | 994篇 |
2000年 | 741篇 |
1999年 | 530篇 |
1998年 | 517篇 |
1997年 | 458篇 |
1996年 | 369篇 |
1995年 | 496篇 |
1994年 | 406篇 |
1993年 | 373篇 |
1992年 | 331篇 |
1991年 | 340篇 |
1990年 | 285篇 |
1989年 | 248篇 |
1988年 | 246篇 |
1987年 | 269篇 |
1986年 | 241篇 |
1985年 | 246篇 |
1984年 | 283篇 |
1983年 | 240篇 |
1982年 | 308篇 |
1981年 | 292篇 |
1980年 | 280篇 |
1979年 | 182篇 |
1978年 | 182篇 |
1977年 | 172篇 |
1976年 | 158篇 |
1975年 | 135篇 |
1974年 | 127篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
- Children with cancer receive many medications outside the hospital administered by their caregivers.
- The study by Walsh et al. shows the number and types of medication errors in these patients. The study includes data from three different centers.
- Importantly, the study shows the types of errors that cause harm. The authors describe how the harmful errors can be prevented.
- We suggest ways these results can be used to identify which patients and families will benefit from additional attention. Providing more help at clinic and in the home may help prevent harmful medication errors in children with cancer.
3.
4.
Mette Nissen Tiina‐Mari Ikheimo Jukka Huttunen Ville Leinonen Henna‐Kaisa Jyrkknen Mikael von und zu Fraunberg 《Neuromodulation》2021,24(1):102-111
ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation. 相似文献
5.
Mohammad Javad Alemzadeh‐Ansari Ali Sarreshtehdari Seifollah Abdi Jamal Moosavi Omid Shafe Parham Sadeghipour Hamidreza Pouraliakbar Bahram Mohebbi 《Seminars in dialysis》2021,34(1):89-93
A 70‐year‐old man with a history of coronary artery bypass grafting 15 years back and arteriovenous (AV) fistula creation in the left arm 1 month back presented with acute coronary syndrome (ACS). He had not received dialysis before his referral. We felt the most likely etiology for these complaints was increased cardiac oxygen demand from an increased cardiac output related to the newly formed left AV fistula. Coronary angiography was done to detect any significant stenosis in the native or grafted vessels. This revealed that the left subclavian artery was totally occluded in the ostioproximal segment and the coronary arteries did not have occlusions to explain the ACS setting. CT angiography confirmed the angiographic findings of the totally occluded left subclavian artery followed by a well‐developed and patent left internal mammary artery to left anterior descending artery. This led to the consideration of a steal syndrome from the coronary artery by the subclavian artery distal to the occlusion. A successful percutaneous endovascular intervention on the left subclavian artery occlusion was performed. Subsequently, the patient became asymptomatic and experienced a dramatic increase in left ventricular ejection fraction. 相似文献
6.
Monica Poiani Myriam Labopin Giorgia Battipaglia Dietrich W. Beelen Johanna Tischer Jürgen Finke Arne Brecht Edouard Forcade Arnold Ganser Jakob R. Passweg Helene Labussiere‐Wallet Ibrahim Yakoub‐Agha Kerstin Schfer‐Eckart Nicolaus Kroeger Blandine Guffroy Annalisa Ruggeri Jordi Esteve Arnon Nagler Mohamad Mohty 《American journal of hematology》2021,96(1):40-50
Karyotypic analysis at time of diagnosis has an important value in determining initial response to treatment, remission duration and overall survival (OS) in acute myeloid leukemia (AML). Less is known about its value before allogeneic hematopoietic cell transplantation (allo‐HCT) in patients transplanted with active disease, either relapsed or primary refractory (Rel‐Ref) AML. We explored the impact of cytogenetic risk (stratification according to MRC‐UK) in 2089 patients with either Ref (n = 972) or Rel AML (n = 1117) transplanted during the period 2000‐2017. Overall, 154 patients had a favorable risk, 1283 had an intermediate risk and 652 had an adverse cytogenetic risk. Median follow‐up was 49 months. Compared to the favorable risk group, intermediate and adverse risk patients were associated with worse leukemia‐free survival and OS and also with a higher incidence of relapse. In a subgroup analysis of patients in the intermediate risk group harboring Fms‐like tyrosine kinase 3‐internal tandem duplication (FLT3‐ITD), this remained an important prognostic factor, being associated with worse outcomes. When analyzing patients according to the intensity of the conditioning regimen, no differences were observed for the main transplant outcomes. In conclusion, in patients diagnosed with AML and transplanted with active disease, karyotype remains an important prognostic factor, allowing splitting patients into different risk groups according to their cytogenetics. Similarly, FLT3‐ITD mutation also remains a negative prognostic factor in this population. 相似文献
7.
8.
C. Vogrig J.-S. Louis F. Avila R. Gillet G. Hossu A. Blum-Moyse P.A. Gondim Teixeira 《Diagnostic and interventional imaging》2021,102(3):181-187
PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences. 相似文献
9.