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   2644篇
  免费   158篇
  国内免费   24篇
耳鼻咽喉   30篇
儿科学   58篇
妇产科学   17篇
基础医学   324篇
口腔科学   39篇
临床医学   168篇
内科学   748篇
皮肤病学   53篇
神经病学   204篇
特种医学   160篇
外科学   484篇
综合类   21篇
预防医学   68篇
眼科学   14篇
药学   126篇
中国医学   18篇
肿瘤学   294篇
  2023年   14篇
  2022年   16篇
  2021年   84篇
  2020年   61篇
  2019年   82篇
  2018年   92篇
  2017年   68篇
  2016年   68篇
  2015年   67篇
  2014年   109篇
  2013年   132篇
  2012年   202篇
  2011年   218篇
  2010年   146篇
  2009年   116篇
  2008年   168篇
  2007年   186篇
  2006年   183篇
  2005年   160篇
  2004年   129篇
  2003年   155篇
  2002年   128篇
  2001年   18篇
  2000年   18篇
  1999年   18篇
  1998年   22篇
  1997年   28篇
  1996年   15篇
  1995年   22篇
  1994年   14篇
  1993年   12篇
  1992年   9篇
  1991年   5篇
  1990年   3篇
  1989年   6篇
  1986年   2篇
  1985年   2篇
  1984年   3篇
  1983年   3篇
  1982年   2篇
  1981年   5篇
  1980年   5篇
  1978年   2篇
  1977年   2篇
  1976年   3篇
  1975年   2篇
  1974年   2篇
  1968年   2篇
  1963年   2篇
  1929年   2篇
排序方式: 共有2826条查询结果,搜索用时 70 毫秒
51.

Background

Long-term clinical outcomes of permanent polymer everolimus-eluting stent (PP-EES) implantation after rotational atherectomy (RA) have not been fully evaluated. We sought to investigate the long-term clinical outcomes of PP-EES implantation after RA and assess the impact of hemodialysis on this treatment strategy.

Methods

Patients who underwent percutaneous coronary intervention (PCI) with PP-EES at 22 institutions between January 2010 and December 2011 were enrolled in this multicenter, observational trial. From a total of 1918 registered patients, 113 patients with 115 de-novo lesions who underwent PCI with PP-EES following RA were retrospectively analyzed. The primary endpoint was a major adverse cardiac event (MACE) defined as the composite of cardiac death, non-fatal myocardial infarction (MI), and clinically driven target lesion revascularization (TLR).

Results

Long-term follow-up was available for 112 patients (99.1%). The median follow-up period was 2.9 (interquartile range 1.9–3.6) years. The mean age of the patients was 72.3?±?8.8?years and 64 patients (56.6%) had chronic kidney disease (≥stage 3, 42 on hemodialysis). The cumulative incidences of MACE, non-fatal MI, and TLR were 22.1%, 5.3%, and 10.6%, respectively. Cox's proportional hazards analysis showed that the independent predictors of TLR were hemodialysis and chronic total occlusion. (HR, 14.1; 95% CI, 1.74–155.5; p?=?0.01, HR, 9.01; 95% CI, 1.34–62.5; p?=?0.02).

Conclusions

PP-EES implantation after lesion modification by RA is considered to be a feasible treatment strategy for heavily calcified lesions. Hemodialysis and chronic total occlusion appeared to be associated with TLR.  相似文献   
52.
INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs.  相似文献   
53.
54.
Excessive salt intake causes hypertension and cardiovascular diseases (CVDs). B-type natriuretic peptide (BNP) is synthesized and released from the ventricle, and is a surrogate marker reflecting various CVDs. Moreover, when a slight BNP elevation is shown, it leads to a poor prognosis in the general population. However, the relationship between salt intake and BNP levels in the general population remains unclear, especially in those without hypertension and heart diseases.In this study, we recruited 1404 participants without hypertension and electrocardiogram abnormalities, who received regular annual health check-ups in Japan. Plasma BNP levels were measured, and daily salt intake levels were evaluated using urinary samples. In addition, some clinical parameters were obtained, and the data were cross-sectionally analyzed.The median of plasma BNP levels was 10.50 pg/mL, and daily salt intake was 8.50 ± 1.85 g. When dividing participants into quartiles according to daily salt intake, those with the highest daily salt intake revealed the highest plasma BNP levels. Plasma BNP levels were significantly and positively associated with daily salt intake. Moreover, multiple linear regression analyses revealed that plasma BNP levels showed a significant positive association with daily salt intake levels after adjustments.Plasma BNP levels were significantly and positively associated with daily salt intake after adjustment in the general population. Plasma BNP levels may be a surrogate marker reflecting salt-induced heart diseases.  相似文献   
55.
OBJECTIVE: Vessel bifurcations are prone to atherosclerotic plaque accumulation. Using volumetric intravascular ultrasound analysis, we investigated atheroma distribution at human coronary bifurcations in vivo. METHODS: We analyzed plaque distribution in 49 left anterior descending coronary artery-diagonal and 20 left circumflex coronary artery-obtuse marginal bifurcations with <50% angiographic stenosis. Cross-sections were analyzed at 1 mm intervals in segments 5 mm proximal and distal from the bifurcation. Planimetry of the lumen and external elastic membrane (EEM) was performed and plaque thickness measured at four different points relative to the branch: 0 degrees, 90 degrees, 180 degrees and 270 degrees. EEM, lumen and plaque volume and percentage plaque burden (plaque volume/EEM volume) were calculated in the proximal and distal segments. The side-branch take-off angle was analyzed in the cross-sectional images. RESULTS: Volumetric analysis showed that EEM, lumen and plaque were larger (P<0.001) in proximal segments than distal segments, whereas percent plaque burden was similar in these segments. Plaque accumulated on the opposite wall to the flow divider. Plaque distribution tended to be more eccentric in distal segments (P=0.05) compared to proximal segments. In 26 of 69 lesions, an asymmetric side-branch take-off was found and was associated with asymmetric plaque distribution compared to those lesions that had a symmetric side-branch take-off (P<0.01). CONCLUSION: We found characteristic patterns of plaque distribution at coronary bifurcations. Proximal segments demonstrated larger plaque volume than distal segments, despite similar percentages of plaque burden. Plaque volume accumulated opposite to the flow divider, especially in distal segments. The side-branch take-off angle in the cross-sectional plane influenced the plaque distribution in bifurcation lesions.  相似文献   
56.
57.
58.
Tahata  Yuki  Hikita  Hayato  Mochida  Satoshi  Enomoto  Nobuyuki  Kawada  Norifumi  Kurosaki  Masayuki  Ido  Akio  Miki  Daiki  Yoshiji  Hitoshi  Takikawa  Yasuhiro  Sakamori  Ryotaro  Hiasa  Yoichi  Nakao  Kazuhiko  Kato  Naoya  Ueno  Yoshiyuki  Yatsuhashi  Hiroshi  Itoh  Yoshito  Tateishi  Ryosuke  Suda  Goki  Takami  Taro  Nakamoto  Yasunari  Asahina  Yasuhiro  Matsuura  Kentaro  Yamashita  Taro  Kanto  Tatsuya  Akuta  Norio  Terai  Shuji  Shimizu  Masahito  Sobue  Satoshi  Miyaki  Tomokatsu  Moriuchi  Akihiro  Yamada  Ryoko  Kodama  Takahiro  Tatsumi  Tomohide  Yamada  Tomomi  Takehara  Tetsuo 《Journal of gastroenterology》2022,57(2):120-132
Journal of Gastroenterology - Direct-acting antiviral (DAA) therapy enables a high rate of sustained virologic response (SVR) in patients with hepatitis C virus associated cirrhosis. However, the...  相似文献   
59.
The coronavirus disease 2019 (COVID-19) is known to cause gastrointestinal symptoms. Recent studies have revealed COVID-19-attributed acute pancreatitis (AP). However, clinical characteristics of COVID-19-attributed AP remain unclear. We performed a narrative review to elucidate relation between COVID-19 and AP using the PubMed database. Some basic and pathological reports revealed expression of angiotensin-converting enzyme 2 and transmembrane protease serine 2, key proteins that aid in the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the pancreas. The experimental and pathological evaluation suggested that SARS-CoV-2 infects human endocrine and exocrine pancreas cells, and thus, SARS-CoV-2 may have a direct involvement in pancreatic disorders. Additionally, systemic inflammation, especially in children, may cause AP. Levels of immune mediators associated with AP, including interleukin (IL)-1β, IL-10, interferon-γ, monocyte chemotactic protein 1, and tumor necrosis factor-α are higher in the plasma of patients with COVID-19, that suggests an indirect involvement of the pancreas. In real-world settings, some clinical features of AP complicate COVID-19, such as a high complication rate of pancreatic necrosis, severe AP, and high mortality. However, clinical features of COVID-19-attributed AP remain uncertain due to insufficient research on etiologies of AP. Therefore, high-quality clinical studies and case reports that specify methods for differential diagnoses of other etiologies of AP are needed.  相似文献   
60.
Background We have reported that percutaneous radiofrequency ablation (RFA) with balloon occlusion of the hepatic artery (balloon-occluded RFA), using an expandable electrode, increases the coagulation area. In this study, we investigated the efficacy of balloon-occluded RFA and balloon-microcatheter-occluded RFA, using a cool RF single electrode.Methods We studies 41 patients with 47 hepatocellular carcinoma (HCC) lesions. We treated 28 patients (32 nodules) with balloon-occluded RFA, 5 patients (6 nodules) with balloon-microcatheter-occluded RFA, and 8 patients (9 nodules) with standard RFA. Initial therapeutic efficacy was evaluated with dynamic computed tomography performed 1 week after one session of treatment.Results One session of treatment was done for 20 nodules (62.5%) in the balloon-occluded RFA group and for 4 nodules (66.7%) in the balloon-microcatheter-occluded RFA group. We compared the coagulation diameter for balloon-occluded RFA (7 nodules), balloon-microcatheter-occluded RFA (6 nodules), and standard RFA (9 nodules) after one application cycle (12min). The greatest dimension of the area coagulated by balloon-occluded RFA was significantly larger (greatest long-axis dimension, 47.6 ± 7.8mm; greatest short-axis dimension, 33.4 ± 7.5mm) than that coagulated by standard RFA (greatest long-axis dimension, 35.3 ± 4.7mm; greatest short-axis dimension, 25.9 ± 3.7mm; P = 0.002 for greatest long-axis dimension; P = 0.041 for greatest short-axis dimension). However, there was significant difference only in the greatest short-axis dimension of the area coagulated comparing balloon-microcatheter-occluded RFA and standard RFA.Conclusions We consider balloon-occluded RFA using a cool RF electrode to be superior to standard RFA for the treatment of HCC, especially when larger coagulation volumes are required.  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