首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9310篇
  免费   583篇
  国内免费   188篇
耳鼻咽喉   205篇
儿科学   61篇
妇产科学   47篇
基础医学   1762篇
口腔科学   167篇
临床医学   877篇
内科学   2257篇
皮肤病学   351篇
神经病学   710篇
特种医学   415篇
外科学   971篇
综合类   65篇
现状与发展   1篇
预防医学   358篇
眼科学   114篇
药学   912篇
中国医学   169篇
肿瘤学   639篇
  2024年   7篇
  2023年   86篇
  2022年   308篇
  2021年   491篇
  2020年   210篇
  2019年   270篇
  2018年   316篇
  2017年   226篇
  2016年   355篇
  2015年   451篇
  2014年   560篇
  2013年   603篇
  2012年   1047篇
  2011年   926篇
  2010年   478篇
  2009年   384篇
  2008年   511篇
  2007年   501篇
  2006年   399篇
  2005年   388篇
  2004年   269篇
  2003年   265篇
  2002年   216篇
  2001年   172篇
  2000年   174篇
  1999年   130篇
  1998年   56篇
  1997年   45篇
  1996年   20篇
  1995年   21篇
  1994年   22篇
  1993年   16篇
  1992年   26篇
  1991年   18篇
  1990年   24篇
  1989年   13篇
  1988年   16篇
  1987年   9篇
  1986年   9篇
  1985年   10篇
  1984年   5篇
  1983年   5篇
  1982年   2篇
  1981年   3篇
  1979年   4篇
  1976年   4篇
  1973年   2篇
  1958年   1篇
  1940年   1篇
  1939年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
PurposeThe mean platelet volume (MPV) is regarded as a marker for thrombosis, atherosclerosis, and inflammation in various vascular diseases. However, it still remains unclear whether plasma MPV is associated with cerebral white matter hyperintensities (WMH) and cerebral microvascular pathology in the elderly population.Materials and MethodsWe examined whether MPV level is associated with the presence of cerebral WMH on brain magnetic resonance imaging from 870 non-stroke outpatient subjects. The subjects were divided into three groups according to the consecutive level of MPV (low T1, middle T2, and high T3 MPV tertile groups). To determine the association of MPV levels with the WMH, logistic regression and receiver operating characteristic curve analyses were conducted.ResultsSubjects with higher MPV level were older and more likely to have hypertension, diabetes mellitus, and low renal function. Cerebral WMH were more prevalent in subjects with higher MPV level. After adjusting for confounding factors, moderate to severe cerebral WMH were significantly associated with high MPV tertile level. This association remained significant after adjusting for other cerebral vascular pathologies. T2 [odds ratio (OR): 1.49, 95% confidence interval (CI): 1.03–2.15] and T3 MPV tertile groups (OR: 1.51, 95%CI: 1.04–2.20) had more cerebral WMH lesions compared to T1 MPV tertile group. In addition, the subjects with higher Fazekas scores showed higher MPV level (p=0.020).ConclusionWe found that high MPV level is independently associated with cerebral WMH. This result suggests that platelet activation plays a role in the development of cerebral WMH.  相似文献   
102.
BackgroundThe risk of device thrombosis and device-oriented clinical outcomes with bioresorbable vascular scaffold (BVS) was reported to be significantly higher than with contemporary drug-eluting stents (DESs). However, optimal device implantation may improve clinical outcomes in patients receiving BVS. The current study evaluated mid-term safety and efficacy of Absorb BVS with meticulous device optimization under intravascular imaging guidance.MethodsThe SMART-REWARD and PERSPECTIVE-PCI registries in Korea prospectively enrolled 390 patients with BVS and 675 patients with DES, respectively. The primary endpoint was target vessel failure (TVF) at 2 years and the secondary major endpoint was patient-oriented composite outcome (POCO) at 2 years.ResultsPatient-level pooled analysis evaluated 1,003 patients (377 patients with BVS and 626 patients with DES). Mean scaffold diameter per lesion was 3.24 ± 0.30 mm in BVS group. Most BVSs were implanted with pre-dilatation (90.9%), intravascular imaging guidance (74.9%), and post-dilatation (73.1%) at proximal to mid segment (81.9%) in target vessel. Patients treated with BVS showed comparable risks of 2-year TVF (2.9% vs. 3.7%, adjusted hazard ratio [HR], 1.283, 95% confidence interval [CI], 0.487–3.378, P = 0.615) and 2-year POCO (4.5% vs. 5.9%, adjusted HR, 1.413, 95% CI, 0.663–3.012, P = 0.370) than those with DES. The rate of 2-year definite or probable device thrombosis (0.3% vs. 0.5%, P = 0.424) was also similar. The sensitivity analyses consistently showed comparable risk of TVF and POCO between the 2 groups.ConclusionWith meticulous device optimization under imaging guidance and avoidance of implantation in small vessels, BVS showed comparable risks of 2-year TVF and device thrombosis with DES.Trial RegistrationClinicalTrials.gov Identifier: NCT02601404, NCT04265443  相似文献   
103.
Soft tissue sealing around zirconia (ZrO2) abutment is critical for the long-term stability of dental implants. The goal of the study is to develop a strong basal lamina (BL)-mediated epithelial attachment to ZrO2 via a novel physicochemical immobilization method. An electrophoretic fusion (EPF) method was applied to fuse a phosphonic acid (PA) linker to ZrO2 discs. Bindings of the PA linker and the following protease activated receptor 4 (PAR4) were verified by Fourier-transform infrared spectroscopy (FITR). Then, ZrO2 discs were doped in platelet-rich plasma (PRP). Platelet-derived growth factor (PDGF) was measured to assess platelet activation. PRP-doped discs were subsequently co-cultured with human gingival epithelial cells (OBA9) to evaluate establishment of basal lamina-mediated epithelial attachment. The EPF method achieved robust immobilization of the PA linker and PAR4 onto the ZrO2 surface. The resultant PAR4-coupled ZrO2 successfully induced platelet aggregation and activation. Furthermore, a BL-mediated epithelial attachment was established. The results are significant for clinical application to minimize the risk of developing peri-implant diseases.  相似文献   
104.
Background/AimsWe examined the efficacy and safety of tegoprazan as a part of first-line triple therapy for Helicobacter pylori eradication.MethodsA randomized, double-blind, controlled, multicenter study was performed to evaluate whether tegoprazan (50 mg)-based triple therapy (TPZ) was noninferior to lansoprazole (30 mg)-based triple therapy (LPZ) (with amoxicillin 1 g and clarithromycin 500 mg; all administered twice daily for 7 days) for treating H. pylori. The primary endpoint was the H. pylori eradication rate. Subgroup analyses were performed according to the cytochrome P450 (CYP) 2C19 genotype, the minimum inhibitory concentration (MIC) of amoxicillin and clarithromycin, and underlying gastric diseases.ResultsIn total, 350 H. pylori-positive patients were randomly allocated to the TPZ or LPZ group. The H. pylori eradication rates in the TPZ and LPZ groups were 62.86% (110/175) and 60.57% (106/175) in an intention-to-treat analysis and 69.33% (104/150) and 67.33% (101/150) in a per-protocol analysis (non-inferiority test, p=0.009 and p=0.013), respectively. Subgroup analyses according to MICs or CYP2C19 did not show remarkable differences in eradication rate. Both first-line triple therapies were well-tolerated with no notable differences.ConclusionsTPZ is as effective as proton pump inhibitor-based triple therapy and is as safe as first-line H. pylori eradication therapy but does not overcome the clarithromycin resistance of H. pylori in Korea (ClinicalTrials.gov identifier NCT03317223).  相似文献   
105.
106.
Chemotherapy-induced cognitive impairment (CICI) has emerged as a significant medical problem without therapeutic options. Using the platinum-based chemotherapy cisplatin to model CICI, we revealed robust elevations in the adenosine A2A receptor (A2AR) and its downstream effectors, cAMP and CREB, by cisplatin in the adult mouse hippocampus, a critical brain structure for learning and memory. Notably, A2AR inhibition by the Food and Drug Administration–approved A2AR antagonist KW-6002 prevented cisplatin-induced impairments in neural progenitor proliferation and dendrite morphogenesis of adult-born neurons, while improving memory and anxiety-like behavior, without affecting tumor growth or cisplatin’s antitumor activity. Collectively, our study identifies A2AR signaling as a key pathway that can be therapeutically targeted to prevent cisplatin-induced cognitive impairments.  相似文献   
107.
BACKGROUND/OBJECTIVESAdolescents who skip breakfast have an increased prevalence of chronic diseases. Thus, we aimed to evaluate whether the intake of rice-based breakfast had positive effects on blood glucose indices and to determine the possibility of diabetes prevalence in Korean youths who habitually skip breakfast.SUBJECTS/METHODSIn this randomized parallel-group controlled trial, 81 subjects who were suitable for compliance among 105 middle-and high-school students aged 12-18 years who usually skipped breakfast were included in this study (rice-meal group [RMG], n = 26; wheat-meal group [WMG], n = 29; general-meal group [GMG], n = 26). The RMG and WMG received a rice-based breakfast and a wheat-based breakfast for 12 weeks, respectively. The anthropometric indices, blood glucose indices, and metabolites were measured at baseline and the endpoint, respectively.RESULTSThe mean body weights in the RMG, WMG, and GMG groups at the endpoint were 62.44 kg, 61.80 kg, and 60.28 kg, respectively, and the mean body weights of the WMG and GMG groups at the endpoint were significantly higher than that at baseline (P < 0.05). The levels of fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) values were significantly decreased in the RMG group at the endpoint compared to baseline (P < 0.05, P < 0.05, respectively). The levels of tryptophan and tyrosine in the WMG group at the endpoint were significantly higher than that those at baseline (P < 0.01, P < 0.05, respectively).CONCLUSIONSRice-based breakfast has positive effects on fasting insulin levels and HOMA-IR in Korean adolescents who skip breakfast. Additionally, it was found that a skipping breakfast could increase the prevalence of diabetes in adolescents who skip breakfast. Therefore, in addition to reducing breakfast skipping, it is vital to develop a rice-based menu that fits teenage preferences to prevent chronic diseases such as diabetes.Trial RegistrationClinical Research Information Service Identifier: KCT0004089  相似文献   
108.
109.
Stickler syndrome is a genetic disorder of connective tissue. One of the major symptoms associated with this disorder is an oro-facial malformation, which may cause a submucous cleft or a complete cleft of the hard palate. A 32-year-old man diagnosed with Stickler syndrome and a submucosal cleft palate (SMCP) visited our hospital with a chief complaint of excessive daytime sleepiness. The patient was diagnosed with severe obstructive sleep apnea (OSA), and administration of a polysomnography test revealed an apnea-hypopnea index (AHI) of 30.9 events/hour (h). Auto-titrating continuous positive airway pressure was initiated to control the OSA symptoms and subsequently the patient showed some improvement. However, due to continuous velopharyngeal insufficiency symptoms, intravelar veloplasty was performed. Three months after surgery, the AHI had decreased to 12.4 events/h. Recent studies have described a greater risk for OSA in individuals with cleft palate, than in the general population. The present case demonstrates surgical success in a patient with OSA and SMCP, suggesting that palatal surgery may be considered an optional surgical treatment for OSA patients with SMCP.  相似文献   
110.
Rationale:The prone position is commonly used in spinal surgery. There have been many studies on hemodynamic changes in the prone position during general anesthesia. We report a rare case of transient left bundle branch block (LBBB) in a prone position.Patient concern:Electrocardiogram (ECG) of a 64-year-old man scheduled for spinal surgery showed normal sinus rhythm change to LBBB after posture change to the prone position.Diagnosis:Twelve lead ECG revealed LBBB. His coronary angio-computed tomography results showed right coronary artery with 30% to 40% stenosis and left circumflex artery with 40% to 50% stenosis. The patient was diagnosed with stable angina and second-degree atrioventricular block of Mobitz type II.Intervention:Nitroglycerin was administered intravenously during surgery. Adequate oxygen was supplied to the patient. After surgery, the patient was prescribed clopidogrel, statins, angiotensin II receptor blocker, and a permanent pacemaker was inserted.Outcome:Surgery was completed without complications. After surgery, the transient LBBB changed to a normal sinus rhythm. The patient did not complain of chest pain or dyspnea.Lesson:The prone position causes significant hemodynamic changes. A high risk of cardiovascular disease may cause ischemic heart disease and ECG changes. Therefore, careful management is necessary.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号