全文获取类型
收费全文 | 585369篇 |
免费 | 41154篇 |
国内免费 | 13779篇 |
专业分类
耳鼻咽喉 | 5700篇 |
儿科学 | 14713篇 |
妇产科学 | 9858篇 |
基础医学 | 56312篇 |
口腔科学 | 11697篇 |
临床医学 | 59505篇 |
内科学 | 82419篇 |
皮肤病学 | 7644篇 |
神经病学 | 34146篇 |
特种医学 | 15934篇 |
外国民族医学 | 36篇 |
外科学 | 56534篇 |
综合类 | 87770篇 |
现状与发展 | 35篇 |
一般理论 | 38篇 |
预防医学 | 54194篇 |
眼科学 | 8126篇 |
药学 | 61982篇 |
511篇 | |
中国医学 | 45259篇 |
肿瘤学 | 27889篇 |
出版年
2024年 | 1723篇 |
2023年 | 9152篇 |
2022年 | 17571篇 |
2021年 | 24072篇 |
2020年 | 21460篇 |
2019年 | 25652篇 |
2018年 | 23650篇 |
2017年 | 21777篇 |
2016年 | 19773篇 |
2015年 | 18555篇 |
2014年 | 32807篇 |
2013年 | 37856篇 |
2012年 | 31938篇 |
2011年 | 35372篇 |
2010年 | 26541篇 |
2009年 | 25003篇 |
2008年 | 25849篇 |
2007年 | 26989篇 |
2006年 | 24261篇 |
2005年 | 21530篇 |
2004年 | 17848篇 |
2003年 | 15729篇 |
2002年 | 12256篇 |
2001年 | 11040篇 |
2000年 | 9165篇 |
1999年 | 7831篇 |
1998年 | 6365篇 |
1997年 | 6211篇 |
1996年 | 5505篇 |
1995年 | 4996篇 |
1994年 | 4834篇 |
1993年 | 3947篇 |
1992年 | 3824篇 |
1991年 | 3389篇 |
1990年 | 2967篇 |
1989年 | 2533篇 |
1988年 | 2437篇 |
1987年 | 2150篇 |
1986年 | 1969篇 |
1985年 | 5011篇 |
1984年 | 5740篇 |
1983年 | 4037篇 |
1982年 | 4525篇 |
1981年 | 4141篇 |
1980年 | 3720篇 |
1979年 | 3347篇 |
1978年 | 2837篇 |
1977年 | 2164篇 |
1976年 | 2379篇 |
1975年 | 1802篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Zongzhang Huang Qigu Yao Jianping Zhu Ying He Yanghao Chen Feng Wu Teng Hua 《Diagnostic and interventional imaging》2021,102(5):279-285
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored. 相似文献
32.
《Annales médico-psychologiques》2021,179(8):744-747
The teaching and clinical practice of professor Yves Pélicier contributed to the international development of a psychiatry centered on the whole of the person in a humanist approach. The theoretical developments were marked by the authenticity of the practice of the therapist and its deep sense of the human being thus truly founding a School. 相似文献
33.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献
34.
35.
36.
37.
《Journal of vascular and interventional radiology : JVIR》2022,33(4):359-367.e8
PurposeTo review and to compare indirectly the outcomes of minimally invasive therapies for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia.Materials and MethodsA literature search via Medline and Cochrane Central databases was completed for randomized control studies published between January 2000 to April 2020 for the following therapies: Rezum, Urolift, Aquablation, and prostatic artery embolization (PAE). Data on the following variables were included: International prostate symptom score (IPSS), maximum urinary flow rate, quality of life, and postvoid residual (PVR). Standard mean differences between treatments were compared through a meta-analysis using transurethral resection of the prostate (TURP) to assess differences in treatment effect.ResultsThere was no significant difference in outcomes between therapies for IPSS at the 3, 6, and 12-month follow ups. Although outcomes for Rezum were only available out to 3 months, there were no consistently significant differences in outcomes when comparing Aquablation versus PAE versus Rezum. TURP PVR was significantly better than Urolift at 3, 6, and 12 months. No significant differences in minor or major adverse events were noted.ConclusionAlthough significant differences in outcomes were limited, Aquablation and PAE were the most durable at 12 months. PAE has been well studied on multiple randomized control trials with minimal adverse events while Aquablation has limited high quality data and has been associated with bleeding-related complications. 相似文献
38.
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment. 相似文献
39.
40.
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion. 相似文献