全文获取类型
收费全文 | 35514篇 |
免费 | 2119篇 |
国内免费 | 160篇 |
专业分类
耳鼻咽喉 | 508篇 |
儿科学 | 827篇 |
妇产科学 | 635篇 |
基础医学 | 4210篇 |
口腔科学 | 657篇 |
临床医学 | 3439篇 |
内科学 | 8436篇 |
皮肤病学 | 412篇 |
神经病学 | 3346篇 |
特种医学 | 1430篇 |
外国民族医学 | 1篇 |
外科学 | 6212篇 |
综合类 | 221篇 |
一般理论 | 18篇 |
预防医学 | 2088篇 |
眼科学 | 472篇 |
药学 | 2022篇 |
中国医学 | 45篇 |
肿瘤学 | 2814篇 |
出版年
2024年 | 25篇 |
2023年 | 205篇 |
2022年 | 394篇 |
2021年 | 890篇 |
2020年 | 544篇 |
2019年 | 884篇 |
2018年 | 1089篇 |
2017年 | 749篇 |
2016年 | 765篇 |
2015年 | 921篇 |
2014年 | 1357篇 |
2013年 | 1829篇 |
2012年 | 2687篇 |
2011年 | 2887篇 |
2010年 | 1643篇 |
2009年 | 1577篇 |
2008年 | 2483篇 |
2007年 | 2623篇 |
2006年 | 2445篇 |
2005年 | 2360篇 |
2004年 | 2133篇 |
2003年 | 1997篇 |
2002年 | 1798篇 |
2001年 | 275篇 |
2000年 | 172篇 |
1999年 | 240篇 |
1998年 | 393篇 |
1997年 | 310篇 |
1996年 | 223篇 |
1995年 | 224篇 |
1994年 | 183篇 |
1993年 | 176篇 |
1992年 | 98篇 |
1991年 | 112篇 |
1990年 | 88篇 |
1989年 | 78篇 |
1988年 | 60篇 |
1987年 | 58篇 |
1986年 | 59篇 |
1985年 | 69篇 |
1984年 | 87篇 |
1983年 | 88篇 |
1982年 | 84篇 |
1981年 | 80篇 |
1980年 | 66篇 |
1979年 | 37篇 |
1978年 | 37篇 |
1977年 | 26篇 |
1975年 | 24篇 |
1974年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Reactions to Alcohol in Sons of Alcoholics and Controls 总被引:3,自引:0,他引:3
This paper synthesizes some major findings coming from our laboratory over the last decade. The data focuses on our search for mechanisms that might contribute to the elevated risk for alcoholism in sons of alcoholic fathers. Consistent results corroborated by several additional groups indicate that the higher risk sons of alcoholics demonstrate less intense reactions to ethanol as measured by their subjective self-reports, measures of body sway, changes in several hormones after drinking, and the intensity or persistence of ethanol-related changes on two electrophysiological measures. The potential implications of these results as they might relate to an enhanced vulnerability to alcoholism, and some possible future research directions, are discussed. 相似文献
42.
Alexander Kulik Marc Ruel Michael E Bourke Lynn Sawyer John Penning Howard J Nathan Thierry G Mesana Pierre Bédard 《European journal of cardio-thoracic surgery》2004,26(4):694-700
OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are routinely used after coronary artery bypass surgery (CABG), yet their effects have seldom been evaluated in randomized controlled settings. The aim of this study was to examine the efficacy and safety of a commonly used NSAID, naproxen. We hypothesized that naproxen would reduce postoperative pain following CABG without increasing complications. METHODS: Patients (N=98) undergoing primary CABG were randomized to receive naproxen (500 mg q12hX5 doses via suppository started 1h after operation, followed by oral 250 mg q8hX6 doses) or placebo. Standard analgesic and anti-emetic regimens were available to both patient groups. Interventions were double-blinded. Primary end-points were postoperative pain measured before and after chest physiotherapy by visual analog scale and pulmonary slow vital capacity (SVC). RESULTS: Baseline characteristics were equivalent between the two groups. Over the first 4 postoperative days, naproxen decreased pain by 47+/-17% on average before chest physiotherapy (P=0.034), and 44+/-13% after chest physiotherapy (P=0.0092). Patients who received naproxen also had better preservation of SVC over the first 4 postoperative days (mean loss of SVC from baseline: 2.1+/-0.1 vs. 2.5+/-0.1l, naproxen vs. placebo, P=0.0032). This was concomitant with a lower white blood cell count observed in naproxen patients (9.2+/-0.3 vs. 12.7+/-1.5x10(9)/l, naproxen vs. placebo, P=0.03). Patients who received naproxen had more chest tube drainage after 4h postoperatively, but there was no difference in the incidence or amount of transfusions. There was no difference in medication use, length of stay, or in the incidence of atrial fibrillation, azotemia, and other complications. CONCLUSIONS: Naproxen is an effective and low-cost adjunct for optimization of pain control and lung recovery after CABG. Its use may result in increased chest tube drainage, but no apparent increase in other complications. 相似文献
43.
PURPOSE: The gum elastic bougie (GEB) has been in use for a long time and allows tracheal intubation in most cases of difficult direct laryngoscopy. Use of the GEB when anatomical landmarks of the upper airway are not recognizable has not been reported. We describe our experience of airway management with the GEB in cases of severe upper airway distortion. CLINICAL FEATURES: Four patients with severe respiratory distress caused by upper airway distortion secondary to various non-malignant causes were managed with the GEB. For these four patients, a rapid sequence induction of anesthesia was performed with a surgeon present during the procedure. The GEB was used as the initial intubating technique in all cases and allowed a rapid and successful tracheal intubation in spite of non-recognizable anatomical structures. The distal hold-up feeling after GEB insertion confirmed, in all cases, the correct intratracheal position of the GEB. CONCLUSION: The GEB can be a valuable tool in cases of difficult airway management caused by upper airway distortion. The lack of visualization of normal pharyngeal structures did not prevent the successful insertion of the GEB in the trachea in the four patients reported. 相似文献
44.
The objective of this article is to summarize the diagnostic criteria recommended by the International Panel on the Diagnosis of Multiple Sclerosis in 2001. The recommendations of another working group, the Consortium of Multiple Sclerosis Centers Consensus Meeting, which met in Vancouver in 2001, concerning the diagnosis and follow-up of patients with multiple sclerosis are also presented in an effort to standardize the protocols for magnetic resonance imaging of these patients. 相似文献
45.
Residual Flow Signals Predict Complete Recanalization in Stroke Patients Treated With TPA 总被引:4,自引:0,他引:4
Lise A. Labiche MD Marc Malkoff MD Andrei V. Alexandrov MD 《Journal of neuroimaging》2003,13(1):28-33
BACKGROUND: Residual blood flow around thrombus prior to treatment predicts success of coronary thrombolysis. The authors aimed to correlate the presence of residual flow signals in the middle cerebral artery (MCA) with completeness of recanalization after intravenous tissue plasminogen activator (TPA). METHODS: The authors studied consecutive patients treated with intravenous TPA therapy who had a proximal MCA occlusion on pretreatment transcranial Doppler (TCD). Patients were continuously monitored for 2 hours after TPA bolus. Absent residual flow signals correspond to the thrombolysis in brain ischemia (TIBI) 0 grade, and the presence of residual flow signals was determined as TIBI 1-3 flow grades. Complete recanalization was defined as flow improvement to TIBI grades 4-5. RESULTS: Seventy-five patients with a proximal MCA occlusion had median pre-bolus NIHSS 16 (85% with > or = 10 points). TPA bolus was given at 141 +/- 56 minutes (median 120 minutes). Complete recanalization was observed in 25 (33%), partial in 23 (31%), and no early recanalization was seen in 27 (36%) patients within 2 hours after TPA bolus. Only 19% with absent residual flow signals (TIBI grade 0, n = 26) on pretreatment TCD had complete early recanalization. If pretreatment TCD showed the presence of any residual flow (TIBI 1-3, n = 49), 41% had complete recanalization within 2 hours of TPA bolus (P = .03). CONCLUSIONS: Patients with detectable residual flow signals before IV TPA bolus are twice as likely to have early complete recanalization. Those with no detectable residual flow signals have less than 20% chance for complete early recanalization with intravenous TPA and may be candidates for intra-arterial therapies. 相似文献
46.
Joanna Rumerman Stephen E. Rubesin M.D. Marc S. Levine William B. Long Igor Laufer 《Abdominal imaging》1988,13(1):200-202
A double-contrast upper gastrointestinal examination on a woman who had undergone endoscopic heater probe therapy one day earlier for multiple arteriovenous malformations revealed shallow, irregular, and linear ulcers at the sites of heater probe coagulation. Multiple shallow ulcers may therefore develop as a direct complication of heater probe therapy. Radiologists should be aware of this complication to avoid diagnostic confusion in these patients. 相似文献
47.
48.
Luis H. Ramirez Morbize Juliéron Marc Bonnay Serge Koscielny Zhongxin Zhao Alain Gouyette Jean-Nicolas Munck 《Investigational new drugs》1995,13(1):51-53
Suramin is an antitrypanosomal compound with confirmed efficacy against several human malignancies. It is generally assumed
that its mechanism of action includes the interaction with different growth factors, unlike most of the anticancer drugs.
Its anticancer activity has not been testedin vivo against squamous cell carcinoma. The purpose of this study was to assess the efficacy and toxicity of suraminin vivo andin vitro on the VX2 tumor model at therapeutic monitored plasma concentrations. We determined the pharmacokinetics of suramin in rabbits,
and modelized its administration in order to obtain plasma concentrations between 150 and 300 μg/ml throughout the treatment
course of 3 weeks. Under these conditions, antitumor effects of suramin were evaluatedin vivo by comparing liver tumor involvement in suramin-treated and control rabbits. Liver involvement was quantified by image analysis
andin vitro effects were also determined at the same concentrations.In vivo, suramin promoted liver tumor growth significantly (p<0.05), compared to untreated controls.In vitro, suramin significantly stimulated tumor cell growth at concentrations above 200 μg/ml (p<0.01). Suramin may have stimulatory
effects on tumor growth in squamous cell carcinoma at relevant plasma drug concentrations. Caution should be taken in further
trials in patients with squamous cell carcinomas. 相似文献
49.
Use of stereotactic PET images in dosimetry planning of radiosurgery for brain tumors: clinical experience and proposed classification. 总被引:13,自引:0,他引:13
Marc Levivier Nicolas Massager David Wikler José Lorenzoni Salvador Ruiz Daniel Devriendt Philippe David Fran?oise Desmedt Stéphane Simon Paul Van Houtte Jacques Brotchi Serge Goldman 《Journal of nuclear medicine》2004,45(7):1146-1154
We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors. 相似文献
50.
Heat Flow and Distribution during Epidural Anesthesia 总被引:43,自引:0,他引:43