全文获取类型
收费全文 | 2844篇 |
免费 | 206篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 44篇 |
妇产科学 | 84篇 |
基础医学 | 311篇 |
口腔科学 | 34篇 |
临床医学 | 264篇 |
内科学 | 572篇 |
皮肤病学 | 43篇 |
神经病学 | 208篇 |
特种医学 | 177篇 |
外科学 | 386篇 |
综合类 | 82篇 |
一般理论 | 2篇 |
预防医学 | 312篇 |
眼科学 | 40篇 |
药学 | 278篇 |
中国医学 | 12篇 |
肿瘤学 | 176篇 |
出版年
2023年 | 20篇 |
2022年 | 63篇 |
2021年 | 115篇 |
2020年 | 62篇 |
2019年 | 93篇 |
2018年 | 132篇 |
2017年 | 77篇 |
2016年 | 84篇 |
2015年 | 84篇 |
2014年 | 94篇 |
2013年 | 130篇 |
2012年 | 210篇 |
2011年 | 201篇 |
2010年 | 103篇 |
2009年 | 82篇 |
2008年 | 139篇 |
2007年 | 126篇 |
2006年 | 139篇 |
2005年 | 150篇 |
2004年 | 122篇 |
2003年 | 121篇 |
2002年 | 110篇 |
2001年 | 61篇 |
2000年 | 52篇 |
1999年 | 46篇 |
1998年 | 18篇 |
1997年 | 19篇 |
1996年 | 10篇 |
1995年 | 17篇 |
1994年 | 13篇 |
1993年 | 15篇 |
1992年 | 33篇 |
1991年 | 23篇 |
1990年 | 41篇 |
1989年 | 23篇 |
1988年 | 20篇 |
1987年 | 18篇 |
1986年 | 17篇 |
1985年 | 8篇 |
1979年 | 12篇 |
1978年 | 11篇 |
1975年 | 9篇 |
1974年 | 10篇 |
1973年 | 11篇 |
1972年 | 9篇 |
1970年 | 8篇 |
1969年 | 13篇 |
1968年 | 11篇 |
1967年 | 8篇 |
1966年 | 14篇 |
排序方式: 共有3059条查询结果,搜索用时 15 毫秒
41.
Occult lung infarction may induce false interpretation of 18F-FDG PET in primary staging of pulmonary malignancies 总被引:3,自引:0,他引:3
Kamel EM McKee TA Calcagni ML Schmidt S Markl S Castaldo S Delaloye AB 《European journal of nuclear medicine and molecular imaging》2005,32(6):641-646
Purpose The aim of the present report is to describe abnormal 18F-fluorodeoxyglucose (FDG) accumulation patterns in the pleura and lung parenchyma in a group of lung cancer patients in whom lung infarction was present at the time of positron emission tomography (PET).Methods Between November 2002 and December 2003, a total of 145 patients (102 males, 43 females; age range 38–85 years) were subjected to whole-body FDG PET for initial staging (n=117) or restaging (n=11) of lung cancer or for evaluation of solitary pulmonary nodules (n=17). Of these patients, 24 displayed abnormal FDG accumulation in the lung parenchyma that was not consistent with the primary lesion under investigation (ipsilateral n=12, contralateral n=9 or bilateral n=3). Without correlative imaging, this additional FDG uptake would have been considered indeterminate in differential diagnosis.Results Of the 24 patients who were identified as having such lesions, six harboured secondary tumour nodules diagnosed as metastases, while in three the diagnosis of a synchronous second primary lung tumour was established. Additionally, nine patients were identified as having post-stenotic pneumonia and/or atelectasis (n=6) or granulomatous lung disease (n=3). In the remaining six (4% of all patients), a diagnosis of recent pulmonary embolism that topographically matched the additional FDG accumulation (SUVmax range 1.4–8.6, mean 3.9) was made. Four of these six patients were known to have pulmonary embolism, and hence false positive interpretation was avoided by correlating the PET findings with those of the pre-existing diagnostic work-up. The remaining two patients were harbouring small occult infarctions that mimicked satellite nodules in the lung periphery. Based on histopathological results, the abnormal FDG accumulation in these two patients was attributed to the inflammatory reaction and tissue repair associated with the pathological cascade of pulmonary embolism.Conclusion In patients with pulmonary malignancies, synchronous lung infarction may induce pathological FDG accumulation that can mimic active tumour manifestations. Identifying this potential pitfall may allow avoidance of false positive FDG PET interpretation. 相似文献
42.
Significance of incidental 18F-FDG accumulations in the gastrointestinal tract in PET/CT: correlation with endoscopic and histopathologic results. 总被引:17,自引:0,他引:17
Ehab M Kamel Miriam Thumshirn Kaspar Truninger Marc Schiesser Michael Fried Barbara Padberg Didier Schneiter Sandro J Stoeckli Gustav K von Schulthess Katrin D M Stumpe 《Journal of nuclear medicine》2004,45(11):1804-1810
This study was undertaken to identify the clinical value of incidentally detected lesions (IDLs) in the gastrointestinal tract (GIT) with (18)F-FDG PET/CT. METHODS: The reported database of 3,281 patients who underwent partial-body (18)F-FDG PET/CT scans from April 2001 to September 2003 was reviewed. Patients with incidental (18)F-FDG accumulations in the GIT that were associated with concomitant abnormal soft-tissue density or wall thickening on the native CT were evaluated. Incidental PET/CT findings were correlated with endoscopic and histopathologic results. RESULTS: According to our selection criteria, 98 (3%) of the 3,281 patients had an IDL of the GIT on (18)F-FDG PET/CT. Correlative endoscopic findings were available in 69 (70%) of 98 patients. Of these, 13 patients (19%) were harboring newly occurring cancers of the GIT in addition to preexisting aerodigestive tract tumors (n = 12) and malignant melanoma (n = 1). Twenty-nine (42%) patients were identified with precancerous lesions, such as advanced colonic adenomas (n = 27), Barrett's esophagus (n = 1), and intestinal metaplasia of the gastric mucosa (n = 1). Inflammatory and other benign GIT lesions were detected in 12 (17%) and 6 (8%) patients, respectively. In 9 (13%) patients, PET/CT was false-positive, showing normal findings in subsequent endoscopic examinations. In 20 (28%) of 69 patients, PET/CT findings had a relevant impact on the clinical management. Twenty-nine (30%) of the 98 patients were not subject to a further endoscopic examination because of the extent and nature of the primary tumor (n = 17), loss to follow-up (n = 7), death shortly after PET (n = 3), and patient unwillingness (n = 2). CONCLUSION: Although IDLs of the GIT on (18)F-FDG PET/CT scans are found only in about 3% of cases, they are associated with a substantial risk of an underlying cancerous or precancerous lesion. Early identification of these occult lesions may have a major impact on the patients' management and outcome. 相似文献
43.
Rebecca M. Dodson Amin Firoozmand Omar Hyder Vania Tacher David P. Cosgrove Nikhil Bhagat Joseph M. Herman Christopher L. Wolfgang Jean-Francois H. Geschwind Ihab R. Kamel Timothy M. Pawlik 《Journal of gastrointestinal surgery》2013,17(12):2123-2132
Background
Assessment of patient performance status is often subjective. Sarcopenia—measurement of muscle wasting—may be a more objective means to assess performance status and therefore mortality risk following intra-arterial therapy (IAT).Methods
Total psoas area (TPA) was measured on cross-sectional imaging in 216 patients undergoing IAT of hepatic malignancies between 2002 and 2012. Sarcopenia was defined as TPA in the lowest sex-specific quartile. Impact of sarcopenia was assessed relative to other clinicopathological factors.Results
Indications for IAT included hepatocellular carcinoma (51 %), intrahepatic cholangiocarcinoma (13 %), colorectal liver metastasis (7 %), or other metastatic disease (30 %). Median TPA among men (568 mm2/m2) was greater than women (413 mm2/m2). IAT involved conventional chemoembolization (54 %), drug-eluting beads (40 %), or yttrium-90 (6 %). Median tumor size was 5.8 cm; most patients had multiple lesions (74 %). Ninety-day mortality was 9.3 %; 3-year survival was 39 %. Factors associated with risk of death were tumor size (HR?=?1.84) and Child's score (HR?=?2.15) (all P?<?0.05). On multivariate analysis, sarcopenia remained independently associated with increased risk of death (lowest vs. highest TPA quartile, HR?=?1.84; P?=?0.04). Sarcopenic patients had a 3-year survival of 28 vs. 44 % for non-sarcopenic patients.Conclusions
Sarcopenia was an independent predictor of mortality following IAT with sarcopenic patients having a twofold increased risk of death. Sarcopenia is an objective measure of frailty that can help clinical decision-making regarding IAT for hepatic malignancies. 相似文献44.
45.
Kamel Sadat M.D. Hari Prakash Diddi M.B.B.S. Berthold Klas B.S. Ayman Haj Asaad M.D. Elif İjlal Çekirdekçi M.D. Aylin Sungur M.D. Selvin Sudhakar M.D. Matthew Cain M.D. Arshad Kamal M.D. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(10):1227-1231
Hypertrophic cardiomyopathy (HCM) is the most common genetically transmitted cardiomyopathy. In patients resistant to medical management, myectomy is the surgical procedure of choice to reduce the symptoms of left ventricular outflow obstruction. Two‐dimensional transesophageal echocardiography (2DTEE) has become part of the operative procedure by decreasing the incidence of postoperative complications. However, because of the three‐dimensional geometry of left ventricular outflow tract, it is unable to comprehensively assess the location and severity of the obstruction and to provide accurate guidance during myectomy. In this study, 10 patients with HCM underwent live/real time three‐dimensional transesophageal echocardiography (3DTEE) intra‐operatively to measure the volume of the resected septum. This volume correlated well with the volume of the resected septal muscle directly obtained using a graduating cylinder containing water (r = 0.9, P < 0.000). 3DTEE may be potentially used as an adjunct to guide the surgeon in performing an adequate myectomy with a lower incidence of residual obstruction and complications such as an iatrogenic ventricular septal defect. 相似文献
46.
47.
48.
Response stratification and survival analysis of hepatocellular carcinoma patients treated with intra‐arterial therapy using MR imaging‐based arterial enhancement fraction
下载免费PDF全文
![点击此处可从《Journal of magnetic resonance imaging : JMRI》网站下载免费的PDF全文](/ch/ext_images/free.gif)
49.
Shohreh Alipour Hashem Montaseri Azadeh Khalili 《Journal of chemotherapy (Florence, Italy)》2016,28(5):411-416
Aerosolized chemotherapeutics leads to higher, localized and continuous concentrations of active agents in lung tissue with lower side effects for other organs. The present study was performed on jugular vein cannulated rats which endothracheally received 4 mg/kg of free paclitaxel powder (Free-PTX), paclitaxel-loaded alginate microparticles (PTX-ALG-MPs) and i.v. paclitaxel (Anzatax®). Pharmacokinetic parameters for Free-PTX and PTX-ALG-MPs contain higher AUC, mean residence time (MRT),half-life and bioavailability, with lower elimination constant (ke). Statistical analysis showed that the amount of paclitaxel per gram of lung tissue after 0.5, 6 and 24 h after administration of Free-PTX was lower than PTX-ALG-MPs. Lung tissue AUC for Free-PTX was lower than PTX-ALG-MPs. According to the obvious advantages obtained, such as dose lowering and increasing paclitaxel residence time and half-life. It should be noted that cell cytotoxicity test on normal airway cell lines was not examined in this study but due to previous reports on safety of inhaled paclitaxel, it can be suggested that pulmonary delivery of paclitaxel can be a useful non-invasive route of administration compared with i.v administration. 相似文献
50.
Khalili P Sundström J Franklin SS Jendle J Lundin F Jungner I Nilsson PM 《Journal of hypertension》2012,30(9):1718-1724
OBJECTIVE:: Pulse pressure (PP) is a risk marker for cardiovascular disease (CVD) in individuals 50 years and older. Inflammation is suggested to influence atherosclerosis, but could also increase PP. We aimed to examine the combined effects of PP and the inflammatory marker sialic acid, and their independent roles on CVD risk. METHODS:: From a population-based study in Sweden between 1962 and 1965, 18?429 men and 19?414 women at the age of 50 or older were selected and followed for first CVD event until 2005. We investigated the biological interactions between sialic acid and PP. The associations of PP and sialic acid with risk of CVD were calculated by using Cox proportional hazards model. Adjustments were made for conventional risk factors, mean arterial pressure (MAP) and socioeconomic status. RESULTS:: The mean age was 59.5 (SD 6.5) years and the number of incident CVD events in men and women were 3641 and 3227, respectively. No biological interaction was seen between PP and sialic acid. In men, the adjusted hazard ratio for PP was 0.92 [95% confidence interval (CI) 0.88-0.96, P?0.0001) for 1 SD of PP, and 1.09 (95% CI 1.05-1.13, P?0.0001) for 1 SD of sialic acid. In women, the corresponding figures were 1.02 (95% CI 0.97-1.07, P?=?0.48) and 1.09 (95% CI 1.05-1.13, P?0.0001). CONCLUSIONS:: Sialic acid but not PP was an independent risk factor for CVD. The risk induced by PP is highly affected by MAP. This suggests that both estimated arterial stiffness and inflammation contribute through different pathways to risk of CVD. 相似文献