全文获取类型
收费全文 | 87747篇 |
免费 | 5584篇 |
国内免费 | 2186篇 |
专业分类
耳鼻咽喉 | 312篇 |
儿科学 | 2633篇 |
妇产科学 | 483篇 |
基础医学 | 4569篇 |
口腔科学 | 143篇 |
临床医学 | 12600篇 |
内科学 | 22098篇 |
皮肤病学 | 311篇 |
神经病学 | 2765篇 |
特种医学 | 3583篇 |
外国民族医学 | 8篇 |
外科学 | 7562篇 |
综合类 | 17987篇 |
预防医学 | 4723篇 |
眼科学 | 253篇 |
药学 | 9246篇 |
91篇 | |
中国医学 | 3931篇 |
肿瘤学 | 2219篇 |
出版年
2024年 | 83篇 |
2023年 | 1232篇 |
2022年 | 2198篇 |
2021年 | 3527篇 |
2020年 | 3600篇 |
2019年 | 2743篇 |
2018年 | 2726篇 |
2017年 | 3180篇 |
2016年 | 3335篇 |
2015年 | 3218篇 |
2014年 | 7116篇 |
2013年 | 6998篇 |
2012年 | 6079篇 |
2011年 | 6242篇 |
2010年 | 4943篇 |
2009年 | 4431篇 |
2008年 | 4195篇 |
2007年 | 4206篇 |
2006年 | 3828篇 |
2005年 | 3208篇 |
2004年 | 2587篇 |
2003年 | 2202篇 |
2002年 | 1701篇 |
2001年 | 1573篇 |
2000年 | 1301篇 |
1999年 | 1131篇 |
1998年 | 882篇 |
1997年 | 838篇 |
1996年 | 771篇 |
1995年 | 690篇 |
1994年 | 654篇 |
1993年 | 478篇 |
1992年 | 450篇 |
1991年 | 394篇 |
1990年 | 386篇 |
1989年 | 303篇 |
1988年 | 285篇 |
1987年 | 229篇 |
1986年 | 211篇 |
1985年 | 269篇 |
1984年 | 235篇 |
1983年 | 108篇 |
1982年 | 139篇 |
1981年 | 122篇 |
1980年 | 112篇 |
1979年 | 92篇 |
1978年 | 67篇 |
1977年 | 63篇 |
1976年 | 47篇 |
1975年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
目的分析同型半胱氨酸(Hcy)、溶血磷脂酸(LPA)及转化生长因子-β1(TGF-β1)在创伤性骨折下肢静脉栓塞中的预测价值。方法选取2019年3月至2020年2月商丘市第一人民医院收治的104例创伤性骨折者(观察组),根据有无DVT:有DVT组33例,无DVT组71例;根据创伤严重程度:轻度组61例,重度组43例。另选取本院同期92例健康体检者设为对照组。比较不同人群、不同病情程度以及有无DVT者血浆Hcy、LPA及血清TGF-β1水平,分析Hcy、LPA及TGF-β1对DVT的预测价值。结果观察组Hcy、LPA及TGF-β1表达水平均明显高于对照组,差异均有统计学意义(P<0.05)。重度组Hcy、LPA及TGF-β1表达水平明显高于轻度组,差异均有统计学意义(P<0.05)。有DVT组者Hcy、LPA及TGF-β1表达水平明显高于无DVT组,差异均有统计学意义(P<0.05)。依据ROC曲线分析可知,Hcy+LPA+TGF-β1三者联合预测创伤性骨折后发生DVT敏感度和特异度分别为88.90%、8130%,明显高于三者单独检测(P<0.05)。结论Hcy、LPA及TGF-β1在创伤性骨折发生下肢静脉栓塞时水平均明显升高,三者联合检测对下肢静脉栓塞早期诊断有重要的临床价值。 相似文献
2.
3.
《Transfusion and apheresis science》2022,61(1):103366
ObjectiveThere is a paucity of data concerning the use of granulocyte colony-stimulating factors (G-CSFs) in pediatric patients with acute lymphoblastic leukemia (ALL). The aim of the present study was to evaluate the effect of G-CSF use on relapse-free and overall survival in 358 consecutive, newly diagnosed pediatric ALL patients uniformly treated at the same institution between April 2012 and April 2020.Materials and MethodsPatients were evaluated in two separate periods, based on the G-CSF treatment approach. All patients who underwent ALL treatment between April 2012 and December 2016 received G-CSF (G-CSF+ arm; n: 245) in the course of the protocol for reducing the risk of febrile neutropenia and/or inducing neutrophil recovery to prevent any treatment delay. No patients after December 2016 received G-CSF, even if they belonged to the high-risk group, and these were included in the G-CSF? arm (n: 113).ResultsEstimated mean relapse-free (106.5 months; 95 % CI 102?110.8 vs 82 months 95 % CI 75.2?88.9; p: 0.794) and overall survival (111.4 months; 95 % CI 108?114.8 vs 85 months 95 % CI 80.4?89.8; p: 0.431) rates were similar between the G-CSF+ and G-CSF? groups.ConclusionsOur findings indicate that G-CSF use during ALL treatment had no effect on relapse rates or overall survival. 相似文献
4.
《Journal of vascular and interventional radiology : JVIR》2022,33(3):249-254.e1
An ovine iliac vein thrombosis model was devised to test a wall-contacting rotational thrombectomy device. Thrombosis was successfully induced in 9 sheep with an average clot length of 31 mm ± 12 and >60% vessel occlusion on angiography. The thrombus was subsequently removed, maintaining normal intraoperative pulmonary arterial pressure (5.9 mm Hg ± 3.6) and complete distal reperfusion after thrombectomy. Additionally, the sheep were without signs of vascular trauma or embolic complications on gross necropsy and histopathologic analysis. The findings from this study support the use of an ovine iliac deep vein thrombosis model for testing of a lower extremity thrombectomy device. 相似文献
5.
目的 通过分析特发性肺纤维化急性加重期(AE-IPF)患者证候与血清生物标志物的关系,为中医辨证治疗提供参考。方法 采用观察性研究设计,收集2019年3月至2019年11月三个中心的AE-IPF患者76例,其中痰热壅肺证26例、痰浊阻肺证50例,并纳入健康志愿者10例作为对照。采用ELISA测定患者血清CCL18、HMGB1、KL-6、MMP-7、SP-A和SP-D水平,分析与中医证候的相关性。结果 AE-IPF患者血清CCL18、HMGB1、KL-6、MMP-7、SP-A和SP-D水平均显著高于健康对照组。血清CCL18、HMGB1、KL-6、MMP-7和SP-D水平在痰热壅肺证和痰浊阻肺证患者间无显著性差异(P>0.05),而血清SP-A水平存在显著性差异(P<0.05)。结论 血清SP-A与AE-IPF证候存在一定的相关性,血清SP-A的浓度升高,与痰热壅肺证关系越密切,反之,血清SP-A浓度降低,则与痰浊阻肺证关系越密切。AE-IPF痰热壅肺证患者的预后可能较痰浊阻肺证患者更差。 相似文献
6.
目的:探讨赣南地区原发性肺鳞癌患者EGFR和ALK基因突变的特点,科学指导此类患者优选靶向用药。方法:入组73例原发性肺鳞癌病例,采用ARMS-PNA技术检测EGFR基因第18、19、20、21外显子突变,应用不平衡法检测其中60例病例的ALK融合基因,回顾性分析EGFR和ALK基因突变患者的临床病理特征。结果:EGFR基因突变8例,阳性率为10.96%(8/73),4例为L858R突变,3例为19del突变,1例为G719X突变。女性患者突变率(66.67%,2/3)明显高于男性患者(8.57%,6/70)(P=0.030),EGFR基因突变在高龄(≥60岁)、进展期(N_(1-3)、Ⅲ+Ⅳ期)患者中相对较高,但差异无统计学意义(P>0.05)。EGFR基因突变与吸烟史、T分期以及肿瘤分布位置均无相关性(P>0.05);ALK融合基因表达2例,阳性率3.33%(2/60),与患者性别、年龄、吸烟史、TNM分期及肿瘤分布类型等各临床病理特征均无相关性(P>0.05);未发现EGFR和ALK基因共存突变病例。结论:赣南地区原发性肺鳞癌患者EGFR和ALK基因突变率相对不高,EGFR基因突变以L858R和19del突变为主,且好发于女性患者,可能是患者病情进展的预测因子之一。 相似文献
7.
8.
《Clinical microbiology and infection》2022,28(8):1120-1125
ObjectivesOur aim was to evaluate the effect of the updated European Organization for Research and Treatment of Cancer (EORTC) and Mycoses Study Group 2019 definitions for invasive pulmonary aspergillosis (IPA) on patient classification and the related all-cause 12-week mortality.MethodsIn this retrospective cohort study from our tertiary care centre, we reclassified patients with haematological malignancy who underwent bronchoalveolar lavage between 2014 and 2019 for suspected IPA using the novel EORTC 2019 criteria. We performed receiver operating characteristic curve analysis to define the optimal cut-off for positive PCR and galactomannan and present survival analyses and their possible association with these diagnostic criteria through post hoc comparisons with log rank and Cox regression.ResultsFrom 323 episodes of suspected IPA in 282 patients, 73 were reclassified: 31 (42.5%) from possible to probable IPA, 5 (6.8%) from EORTC criteria not met to probable IPA, and 37 (50.7%) from EORTC criteria not met to possible IPA. Probable IPA increased therefore 11.1% (64/323, 19.8% to 100/323, 30.9%), mostly due to positive PCR (31/36, 86.1%). There was no difference in mortality between newly defined possible and probable IPA (log rank p = 0.950). Mortality was higher in probable cases with lower cycle thresholds (Ct values) versus higher Ct values (p = 0.004). Receiver operating characteristic curve analysis showed an optimal Ct value cut-off of 36.8 with a sensitivity of 75% (95% CI 64.9%–85.1%) and a specificity of 61.7% (95% CI 53.5–69.9) for 12-week mortality.DiscussionThe new EORTC criteria led to 11.1% more probable IPA diagnoses, mostly due to Aspergillus PCR. Restricting positive PCR to below a certain threshold might improve the discrimination of the new EORTC IPA categories for mortality. 相似文献
9.
10.
《Medical Journal Armed Forces India》2022,78(1):17-23
Pulmonary thromboembolism (PTE) is an important cause of mortality/morbidity even today despite advancement in clinical understanding as well as diagnostic facilities. Clinical diagnosis of PTE is often challenging because of nonspecific sign/symptoms. Adherence to clinical decision-making protocols and appropriate use of diagnostic modalities like computed tomography pulmonary angiography can resolve the diagnostic dilemma in most cases and help in the overall management of PTE. This article deals with various concerns as well as controversies surrounding accurate diagnosis of PTE as on date. 相似文献