全文获取类型
收费全文 | 16378篇 |
免费 | 1137篇 |
国内免费 | 72篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 350篇 |
妇产科学 | 530篇 |
基础医学 | 2757篇 |
口腔科学 | 189篇 |
临床医学 | 1607篇 |
内科学 | 3931篇 |
皮肤病学 | 138篇 |
神经病学 | 1455篇 |
特种医学 | 549篇 |
外国民族医学 | 1篇 |
外科学 | 2571篇 |
综合类 | 143篇 |
一般理论 | 7篇 |
预防医学 | 957篇 |
眼科学 | 135篇 |
药学 | 1007篇 |
中国医学 | 21篇 |
肿瘤学 | 1163篇 |
出版年
2023年 | 50篇 |
2022年 | 92篇 |
2021年 | 221篇 |
2020年 | 132篇 |
2019年 | 255篇 |
2018年 | 328篇 |
2017年 | 205篇 |
2016年 | 264篇 |
2015年 | 355篇 |
2014年 | 471篇 |
2013年 | 683篇 |
2012年 | 997篇 |
2011年 | 1122篇 |
2010年 | 711篇 |
2009年 | 691篇 |
2008年 | 1122篇 |
2007年 | 1133篇 |
2006年 | 1124篇 |
2005年 | 1185篇 |
2004年 | 1084篇 |
2003年 | 1058篇 |
2002年 | 1064篇 |
2001年 | 171篇 |
2000年 | 145篇 |
1999年 | 181篇 |
1998年 | 259篇 |
1997年 | 236篇 |
1996年 | 189篇 |
1995年 | 193篇 |
1994年 | 169篇 |
1993年 | 165篇 |
1992年 | 145篇 |
1991年 | 105篇 |
1990年 | 91篇 |
1989年 | 90篇 |
1988年 | 82篇 |
1987年 | 67篇 |
1986年 | 77篇 |
1985年 | 55篇 |
1984年 | 71篇 |
1983年 | 56篇 |
1982年 | 71篇 |
1981年 | 88篇 |
1980年 | 45篇 |
1979年 | 48篇 |
1978年 | 45篇 |
1977年 | 29篇 |
1976年 | 28篇 |
1975年 | 31篇 |
1973年 | 22篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
Kazuo Okura Takafumi Kato Jacques Y Montplaisir Barry J Sessle Gilles J Lavigne 《Clinical neurophysiology》2006,117(2):269-278
OBJECTIVE: The aim of this study was to make a quantitative analysis of the changes in cranial and limb muscle activity from wakefulness to light and deep sleep stages and during rapid eye movement (REM) sleep of normal subjects. METHODS: Polysomnographic recordings were made of the sleep of 9 healthy human subjects, including electromyograms of the suprahyoid, temporalis and masseter cranial muscles and the anterior tibialis limb muscle. Quantitative assessments of EMG activity were carried out with root mean square (RMS) and frequency-spectral analysis (FSA) methods. RESULTS: From wakefulness to sleep, a significant reduction (-25.2 to -71.2%; P < 0.01) was observed in EMG activity (for both RMS and FSA) of the 3 cranial muscles using both methods of analysis. The EMG activity of suprahyoid muscle further decreased from non-REM to REM sleep (-17.8 to -43.0%; P < 0.01). In contrast, the EMG activity of the anterior tibialis muscle was only slightly reduced across sleep stages and did not further reduce during REM sleep. During REM sleep, all the 4 muscles maintained minimal activity. CONCLUSIONS: The maintenance of muscle activity during REM sleep suggests that a minimal level of activity is required to preserve physiological functions (e.g. airway patency, posture) related to homeostasis and bodily protection. SIGNIFICANCE: This study suggests that quantitative sleep EMG analysis is important for understanding the mechanisms of sleep-related movement disorders or when objective assessment of changes in EMG activity are needed for diagnostic purposes or for the assessment of drug efficiency. 相似文献
62.
The Effect of Antiepileptic Drugs on Cognition: Patient Perceived Cognitive Problems of Topiramate versus Levetiracetam in Clinical Practice 总被引:1,自引:0,他引:1
Hans-Peter R. Bootsma †Albert P. Aldenkamp Leonie Diepman Jacques Hulsman Danielle Lambrechts Loes Leenen Marian Majoie Ad Schellekens †Marc de Krom 《Epilepsia》2006,47(S2):24-27
Summary: Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
63.
Nadim M. Zacca Neal S. Kleiman Arsenio R. Rodriguez Jacques Heibig David Warth Scott Harris Steven T. Minor Albert E. Raizner 《Catheterization and cardiovascular interventions》1992,26(2):92-97
Previous clinical use of the Rotablator(TM) In coronary artery disease has involved a sequential increase in burr sizes up to 2 mm in diameter and has often utilized balloon adjunct to achieve an optimal result. We report our experience and describe our technique using a single, large burr (2.25, 2.5, or 2.75 mm diameter) without balloon assistance. The burr size was selected to approximate 70–90 percent of the apparent normal lumen diameter. Thirty-one patients with 36 lesions of complex morphology (eccentric, irregular, calcified, ulcerated, at bends, at bifurcations, completely occluded, as well as balloon failures) were successfully treated with the Rotablator(TM). Results were assessed by computerized quantitative angiography. The percent diameter stenosis (mean ± SD) for the group was reduced from 69.8 ± 11.3% to 30.9 ± 10% (p < 0.001). The mean absolute diameter stenosis increased from 0.9 ± 0.3 mm to 2.2 ± 0.3 mm (p < 0.001). Angiographically visible dissections were seen in 4 patients and were uncomplicated in 2. One patient had a non-Q-wave myocardial infarction. A fourth patient had a presumed acute occlusion 36 hr after the procedure, necessitating emergency bypass surgery, but without Q waves on the electrocardiogram or wall-motion abnormalities on the echocar-diogram. Nitroglycerin was infused through the Rotablator(TM) catheter and has considerably lowered the degree and frequency of spasm. No other acute complications occurred. The mean procedure time using a single burr was shorter than when multiple burrs were used: 56.5 vs. 97.3 min, respectively (p < 0.05). The use of a single, large-size Rotablator(TM) burr is an effective method of treating complex coronary stenoses without balloon assistance and has an encouragingly low complication rate and short procedure time. © 1992 Wiley-Liss, Inc. 相似文献
64.
65.
P F Jacques 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1992,62(3):252-255
Data collected as part of a study designed to examine the nutritional status of non-institutionalized elderly individuals, ages 60-100 years, residing in the Boston area were used to investigate the relationship between blood pressure (BP) and vitamin C intake reported by three-day diet records. Four hundred and ten subjects not taking antihypertensive medications were grouped into 5 categories of vitamin C intake: < 60, 60-119, 120-179, 180-239, > or = 240 mg/day. Relative differences in systolic and diastolic BP between subjects consuming > or = 240 mg/day compared to those consuming < 60 mg/day were -6.9% (p < 0.05) and -6.6% (p < 0.05), respectively. The prevalence of elevated BP (systolic > or = 160 mmHg or diastolic > or = 100 mmHg) was approximately 50% lower (p < 0.05) across this range of vitamin C intake. Adjustment of these associations for age, sex, body mass, smoking, dietary sodium:potassium ratio, and other dietary factors did little to alter the relationship between vitamin C and BP. These results lend support to the hypothesis that vitamin C and BP are related, but further research is required to test whether the relationship is causal. 相似文献
66.
67.
Wassim Daher Lydie Pelinski Sylvie Klieber Freddy Sadoun Viviane Meunier Martine Bourrié Christophe Biot Fran?ois Guillou Gérard Fabre Jacques Brocard Laurent Fraisse Jean-Pierre Maffrand Jamal Khalife Daniel Dive 《Drug metabolism and disposition》2006,34(4):667-682
Ferroquine (SSR97193) has been shown to be a promising antimalarial, both on laboratory clones and on field isolates. So far, no resistance was documented in Plasmodium falciparum. In the present work, the metabolic pathway of ferroquine, based on experiments using animal and human hepatic models, is proposed. Ferroquine is metabolized mainly via an oxidative pathway into the major metabolite mono-N-demethyl ferroquine and then into di-N,N-demethyl ferroquine. Some other minor metabolic pathways were also identified. Cytochrome P450 isoforms 2C9, 2C19, and 3A4 and, possibly in some patients, isoform 2D6, are mainly involved in ferroquine oxidation. The metabolites were synthesized and tested against the 3D7 (chloroquine-sensitive) and W2 (chloroquine-resistant) P. falciparum strains. According to the results, the activity of the two main metabolites decreased compared with that of ferroquine; however, the activity of the mono-N-demethyl derivative is significantly higher than that of chloroquine on both strains, and the di-N-demethyl derivative remains more active than chloroquine on the chloroquine-resistant strain. These results further support the potential use of ferroquine against human malaria. 相似文献
68.
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
69.
Pelvic floor muscle training with biofeedback and bladder training in elderly women: a feasibility study. 总被引:1,自引:0,他引:1
Louise Perrin Sharon Wood Dauphinée Jacques Corcos James A Hanley George A Kuchel 《Journal of wound, ostomy, and continence nursing》2005,32(3):186-199
OBJECTIVE: It is generally assumed that interventions used to treat urinary incontinence (UI) in young women could simply be applied to older competent and motivated women, but these assumptions have not been formally tested. The purpose of this study was to determine the feasibility of using physical therapies to treat UI in older women. DESIGN: Twelve-week time series. SETTINGS AND SUBJECTS: We recruited women older than 75 years with UI from an outpatient urology clinic and a waiting list for incontinence surgery. METHODS: After a baseline evaluation, the women collected data on their incontinence symptoms and bladder habits for 3 weeks using the 72-hour voiding diary and the 24-hour pad test. They then received 6 physical therapy treatments consisting of a combination of bladder training and pelvic floor muscle training assisted with biofeedback for 6 weeks. This was followed by another 3-week period of data collection and a final evaluation. RESULTS: Ten women participated in the study; 7 completed it. They were all comfortable with the treatment. They complied with the study demands in terms of attendance at treatment session (100%), data collection (96%), and completion of exercises at home (82%). The authors observed a decrease in the number of incontinent and urgency episodes. CONCLUSION: This preliminary study demonstrates that some women older than 75 years are good candidates to undertake physical therapies for UI and follow study demands. Random controlled studies that include this population will provide evidence regarding the effectiveness of these therapies. 相似文献
70.
John M. H. de Klerk Bernard A. Zonnenberg Alfred D. van het Schip Aalt van Dijk Shiuw H. Han Jacques M. S. R. Quirijnen Geert H. Blijham Peter R van Rijk 《European journal of nuclear medicine and molecular imaging》1994,21(10):1114-1120
Rhenium-186 hydroxyethylidene diphosphonate (186Re-HEDP) has been used for the palliative treatment of metastatic bone pain. A phase 1 dose escalation study was performed using 186Re-HEDP Twenty-four patients with hormone-resistant prostate cancer entered the study. Each patient had at least four bone metastases and adequate haematological function. Groups of at least three consecutive patients were treated with doses starting at 1295 MBq and increasing to 3515 MBq (escalated in increments of 555 MBq). Thrombocytopenia proved to be the dose-limiting toxicity, while leucopenia played a minor role. Early death occurred in one patient (10 days after administration) without clear relationship to the 186Re-HEDP therapy. Transient neurological dysfunction was seen in two cases. Two patients who received 3515 MBq 186Re-HEDP showed grade 3 toxicity (thrombocytes 25–50 × 109/1), defined as unacceptable toxicity. After treatment alkaline phosphatase levels showed a transient decrease in all patients (mean: 26% ± 10% IUA; range: 11%–44%). Prostate-specific antigen values showed a decline in eight patients, preceded by a temporary increase in three patients. From this study we conclude that the maximally tolerated dose of 186Re-HEDP is 2960 MBq. A placebo-controlled comparative study on the efficacy of 186Re-HEDP has been initiated. 相似文献