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   15640篇
  免费   971篇
  国内免费   188篇
耳鼻咽喉   382篇
儿科学   200篇
妇产科学   288篇
基础医学   2735篇
口腔科学   309篇
临床医学   1212篇
内科学   3073篇
皮肤病学   439篇
神经病学   1181篇
特种医学   1045篇
外科学   2082篇
综合类   71篇
现状与发展   3篇
一般理论   10篇
预防医学   610篇
眼科学   428篇
药学   1261篇
中国医学   156篇
肿瘤学   1314篇
  2024年   12篇
  2023年   133篇
  2022年   379篇
  2021年   669篇
  2020年   269篇
  2019年   439篇
  2018年   524篇
  2017年   410篇
  2016年   610篇
  2015年   876篇
  2014年   957篇
  2013年   1046篇
  2012年   1592篇
  2011年   1437篇
  2010年   846篇
  2009年   710篇
  2008年   898篇
  2007年   907篇
  2006年   770篇
  2005年   625篇
  2004年   518篇
  2003年   468篇
  2002年   380篇
  2001年   293篇
  2000年   237篇
  1999年   174篇
  1998年   71篇
  1997年   55篇
  1996年   34篇
  1995年   36篇
  1994年   24篇
  1993年   30篇
  1992年   38篇
  1991年   39篇
  1990年   34篇
  1989年   36篇
  1988年   28篇
  1987年   32篇
  1986年   17篇
  1985年   15篇
  1984年   10篇
  1983年   10篇
  1981年   14篇
  1980年   7篇
  1979年   14篇
  1978年   10篇
  1977年   10篇
  1976年   10篇
  1975年   9篇
  1973年   6篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
PURPOSE: The authors evaluated the utility of F-18 fluorodeoxyglucose (FDG) coincidence detection (CoDe) positron emission tomography (PET) for staging, post-treatment evaluation, and follow-up assessment of patients with malignant lymphomas. MATERIALS AND METHODS: Fifty-eight patients with histologically proved malignant lymphomas (4 Hodgkin's disease, 54 non-Hodgkin's lymphoma) underwent CoDe PET using F-18 FDG. CoDe PET was performed using a dual-head gamma camera equipped with coincidence detection circuitry. Of the 87 CoDe PET studies, 26 were performed for staging, 38 for post-treatment evaluation, and 23 for follow-up evaluation of recurrence. The entire trunk, from the cervical to the inguinal regions, or selected regions were scanned with the patient in the supine position. No attenuation correction was made and reconstruction was performed using filtered back-projection rather than iterative reconstruction. CoDe PET findings were compared with corresponding results of computed tomographic (CT) and magnetic resonance imaging (MRI), tissue biopsy, or clinical follow-up. RESULTS: For staging, 52 sites were positive on CoDe PET or CT-MRI. CoDe PET detected 49 sites (94%), and CT-MRI showed 47 sites (90%). CoDe PET detected five more lymphomatous lesions and missed three lesions. For post-treatment evaluation, CoDe PET showed a positive predictive value of 100% and a negative predictive value of 83%, but the validated cases numbered only 11. For follow-up for recurrence, CoDe PET had a negative predictive value of 90%, but frequent false-positive findings were noted in the head and neck region as a result of underlying inflammatory changes. CONCLUSIONS: For staging, FDG CoDe PET alone without attenuation correction is not sensitive enough to be used as an independent imaging method, especially for small abdominal lesions. However, it appears to be an accurate method for assessing residual disease and for patient follow-up.  相似文献   
102.
Nasopharyngeal carcinoma (NPC) arises from the mucosal epithelium of the nasopharynx and is constantly associated with Epstein–Barr virus type 1 (EBV‐1) infection. We carried out a genome‐wide association study (GWAS) of 575,247 autosomal SNPs in 184 NPC patients and 236 healthy controls of Malaysian Chinese ethnicity. Potential association signals were replicated in a separate cohort of 260 NPC patients and 245 healthy controls. We confirmed the association of HLA‐A to NPC with the strongest signal detected in rs3869062 (p = 1.73 × 10?9). HLA‐A fine mapping revealed associations in the amino acid variants as well as its corresponding SNPs in the antigen peptide binding groove (pHLA‐A‐aa‐site‐99 = 3.79 × 10?8, prs1136697 = 3.79 × 10?8) and T‐cell receptor binding site (pHLA‐A‐aa‐site‐145 = 1.41 × 10?4, prs1059520 = 1.41 × 10?4) of the HLA‐A. We also detected strong association signals in the 5′‐UTR region with predicted active promoter states (prs41545520 = 7.91 × 10?8). SNP rs41545520 is a potential binding site for repressor ATF3, with increased binding affinity for rs41545520‐G correlated with reduced HLA‐A expression. Multivariate logistic regression diminished the effects of HLA‐A amino acid variants and SNPs, indicating a correlation with the effects of HLA‐A*11:01, and to a lesser extent HLA‐A*02:07. We report the strong genetic influence of HLA‐A on NPC susceptibility in the Malaysian Chinese.  相似文献   
103.
Recent strategies for treating CML patients have focused on investigating new combinations of tyrosine kinase inhibitors (TKIs) as well as identifying novel translational research agents that can eradicate CML leukemia‐initiating cells (CML‐LICs). However, little is known about the therapeutic benefits such CML‐LIC targeting therapies might bring to CML patients. In this study, we investigated the therapeutic potential of EW‐7197, an orally bioavailable transforming growth factor‐β signaling inhibitor which has recently been approved as an Investigational New Drug (NIH, USA), to suppress CML‐LICs in vivo. Compared to TKI treatment alone, administration of TKI plus EW‐7197 to CML‐affected mice significantly delayed disease relapse and prolonged survival. Notably, combined treatment with EW‐7197 plus TKI was effective in eliminating CML‐LICs even if they expressed the TKI‐resistant T315I mutant BCR‐ABL1 oncogene. Collectively, these results indicate that EW‐7197 may be a promising candidate for a new therapeutic that can greatly benefit CML patients by working in combination with TKIs to eradicate CML‐LICs.  相似文献   
104.
We retrospectively investigated the incidence, risk factors, and outcomes of SOS (sinusoidal obstruction syndrome; previously veno-occlusive disease [VOD]) after allogeneic hematopoietic stem cell transplantation (alloHSCT) in aplastic anemia. Two hundred and sixty patients were included in the analysis. SOS developed in 7.3% (n = 19/260) of patients. Classical Cy (200 mg/m2)-ATG was the most common conditioning regimen (84.2%) in the SOS group. The SOS mortality rate was 4/19 (21.1%). Univariate analyses revealed that Cy 200 mg/m2 conditioning (p = 0.035), classical Cy-ATG conditioning (p = 0.007), and horse ATG conditioning (p < 0.001) were significant risk factors for developing SOS. Multivariate analysis revealed that only horse ATG conditioning was a poor prognostic factor (HR = 3.484; 95% CI 1.226–9.904; p = 0.002). Rabbit ATG (HR 12.719; 95% CI 2.332–69.373; p = 0.003) and weight gain > 10% (HR 35.655; 95% CI 2.208–575.805; p = 0.012) were risk factors in the overall SOS group. Both rabbit ATG conditioning and weight gain of more than 10% were associated with poor overall survival with a median of 1.2 months (5Y survival rate, any risk factor vs. none: 74.6% vs. 0.0%; p < 0.001; Fig. 2) in the SOS group.  相似文献   
105.
Choi BH  Kim W  Wang QC  Kim DC  Tan SN  Yong JW  Kim KT  Yoon HS 《Cancer letters》2008,261(1):37-45
Here, we demonstrate that kinetin riboside (KR), a cytokinin analog, induces apoptosis in HeLa and mouse melanoma B16F-10 cells. KR disrupted the mitochondrial membrane potential and induced the release of cytochrome c and activation of caspase-3. Bad were upregulated while Bcl-2 was down-regulated under KR exposure. A tumor growth in mice was dramatically suppressed by KR. In contrast, human skin fibroblast CCL-116 and bovine primary fibroblast cells show resistances to KR and no significant changes in Bad, Bcl-X(L,) and cleaved PARP were observed. Our data suggest that KR selectively induces apoptosis in cancer cells through the classical mitochondria dependent apoptosis pathway.  相似文献   
106.
ObjectiveTo investigate the long-term outcomes of percutaneous treatment of benign biliary strictures using temporary placement of a retrievable expanded polytetrafluoroethylene (PTFE) covered stent.Materials and MethodsWe retrospectively analyzed the outcomes of 148 patients (84 male and 64 female; age range, 11–92 years) who underwent percutaneous transhepatic placement and removal of a retrievable PTFE-covered stent for the treatment of benign biliary strictures between March 2007 and August 2019 through long-term follow-up. Ninety-two patients had treatment-naïve strictures and 56 had recurrent/refractory strictures.ResultsStent placement was technically successful in all 148 patients. The mean indwelling period of the stent was 2.4 months (median period, 2.3 months; range, 0.2–7.7 months). Stent migration, either early or late, occurred in 28 (18.9%) patients. Clinical success, defined as resolution of stricture after completing stent placement and removal, was achieved in 94.2% (131 of 139 patients). The overall complication rate was 15.5% (23 of 148 patients). During the mean follow-up of 60.2 months (median period, 52.7 months; range, 1.6–146.1 months), 37 patients had a recurrence of clinically significant strictures at 0.5–124.5 months after removal of biliary stent and catheter (median, 16.1 months). The primary patency rates at 1, 3, 5, 7, and 10 years after removal of biliary stent and catheter were 88.2%, 70.0%, 66.2%, 60.5%, and 54.5%, respectively. In the multivariable Cox proportional hazard regression analysis, sex, age, underlying disease, relation to surgery, stricture type, biliary stones, history of previous treatment, and stricture site were not significantly associated with the primary patency.ConclusionLong-term outcomes suggest that percutaneous treatment of benign biliary strictures using temporary placement of retrievable PTFE-covered stents may be a clinically effective method.  相似文献   
107.
108.
109.
The prognostic value of arterial stiffness in patients with diabetes mellitus (DM) remains unclear. The aim of this study was to investigate the association between brachial-ankle pulse wave velocity (baPWV) and the occurrence of cardiovascular events in people with DM. A total of 2714 subjects (mean age, 63.6 years; males, 59.3%) with type 2 DM and without documented cardiovascular disease and stroke were analyzed. The primary end-point of this study was composite cardiovascular events of cardiac death, non-fatal myocardial infarction, coronary revascularization and stroke. There were 118 composite events (4.3%) during a median follow-up period of 3.84 years (interquartile range, 1.60–5.52 years). In multivariable Cox regression analysis, higher baPWV (≥1672 cm/s) was associated with composite events even after controlling for potential confounders (hazard ratio [HR], 2.00; 95% confidence interval [CI], 1.31–3.07; P = .001). Compared to the lowest baPWV tertile, both middle (HR, 1.84; 95% CI, 1.03–3.27; P = .037) and the highest (HR, 2.97; 95% CI, 1.69–5.22; P < .001) tertile of baPWV were associated with increased risk of cardiovascular events in the same multivariable model. In conclusion, the baPWV was associated with cardiovascular events in people with type 2 DM. Considering the simplicity and convenience of baPWV measurement, baPWV may be useful for risk stratification of people with type 2 DM.  相似文献   
110.
This study aimed to investigate the long-term clinical efficacy of and satisfaction with integrative Korean medicine (KM) treatment in patients with shoulder osteoarthritis (SOA). We conducted a prospective observational study of patients with SOA. Patients aged 19 years and older who underwent inpatient treatment for more than 1 week were eligible for enrollment in the study. The primary evaluation index was the numeric rating scale for shoulder pain. Sub-evaluation indices included the Shoulder Pain and Disability Index for shoulder function, EuroQol-5-dimension score for overall quality of life, and Patient Global Impression of Change. Outcome measures were assessed at admission, discharge, and follow-up. For the follow-up questionnaire survey, the following information was collected: current status, surgery after discharge, reasons for finding integrative KM treatment satisfactory/unsatisfactory, and quality of life after discharge. In total, 186 patients were enrolled in the primary analysis, and 103 patients completed the follow-up survey. The mean number of days of follow-up was 1019 ± 439. Compared with the baseline, the mean differences in the numeric rating scale and Shoulder Pain and Disability Index were 3.05 ± 0.34 and 36.06 ± 5.53, respectively. Regarding the Patient Global Impression of Change, 89 out of 103 (86.4%) patients chose “minimally improved” or better. Furthermore, the EuroQol-5-dimension score also increased, showing an improvement of health-related quality of life after treatment. Integrative KM treatment is a potential option for reducing pain severity and improving function and health-related quality of life in patients with SOA. Prospective randomized studies would support this finding for the next step.  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