全文获取类型
收费全文 | 5823篇 |
免费 | 290篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 134篇 |
妇产科学 | 195篇 |
基础医学 | 728篇 |
口腔科学 | 70篇 |
临床医学 | 448篇 |
内科学 | 1430篇 |
皮肤病学 | 72篇 |
神经病学 | 540篇 |
特种医学 | 352篇 |
外科学 | 948篇 |
综合类 | 20篇 |
一般理论 | 8篇 |
预防医学 | 413篇 |
眼科学 | 87篇 |
药学 | 278篇 |
中国医学 | 4篇 |
肿瘤学 | 371篇 |
出版年
2024年 | 4篇 |
2023年 | 26篇 |
2022年 | 42篇 |
2021年 | 89篇 |
2020年 | 78篇 |
2019年 | 109篇 |
2018年 | 95篇 |
2017年 | 92篇 |
2016年 | 116篇 |
2015年 | 125篇 |
2014年 | 190篇 |
2013年 | 282篇 |
2012年 | 436篇 |
2011年 | 515篇 |
2010年 | 290篇 |
2009年 | 275篇 |
2008年 | 398篇 |
2007年 | 455篇 |
2006年 | 365篇 |
2005年 | 415篇 |
2004年 | 365篇 |
2003年 | 320篇 |
2002年 | 287篇 |
2001年 | 60篇 |
2000年 | 27篇 |
1999年 | 40篇 |
1998年 | 67篇 |
1997年 | 70篇 |
1996年 | 61篇 |
1995年 | 41篇 |
1994年 | 50篇 |
1993年 | 44篇 |
1992年 | 21篇 |
1991年 | 21篇 |
1990年 | 22篇 |
1989年 | 13篇 |
1988年 | 23篇 |
1987年 | 23篇 |
1986年 | 20篇 |
1985年 | 21篇 |
1984年 | 15篇 |
1983年 | 16篇 |
1982年 | 18篇 |
1981年 | 13篇 |
1980年 | 12篇 |
1979年 | 7篇 |
1978年 | 9篇 |
1977年 | 10篇 |
1975年 | 4篇 |
1974年 | 8篇 |
排序方式: 共有6122条查询结果,搜索用时 15 毫秒
11.
Willem P Godefroy Martijn J A Malessy Aimee A M Tromp Andel G L van der Mey 《Otology & neurotology》2007,28(4):546-550
OBJECTIVE: To evaluate functional recovery after facial-hypoglossal nerve transfer with direct coaptation of the intratemporal part of the facial nerve. STUDY DESIGN: Retrospective study. SETTING: University-based tertiary referral center. PATIENTS: Nine patients who underwent facial-hypoglossal transfer surgery between 2001 and 2006 to treat a unilateral complete facial nerve palsy. INTERVENTION: The facial nerve is mobilized in the temporal bone, transsected at the second genu, transferred and directly coaptated to a partially incised hypoglossal nerve. MAIN OUTCOME MEASURES: The House-Brackmann grading system was used to evaluate facial nerve reinnervation. Tongue atrophy and movements were documented. Quality of life related to facial function was assessed using the validated Facial Disability Index. RESULTS: A House-Brackmann Grade III (86%) was achieved in six patients, and Grade IV (14%) in one patient with an average follow-up of 22 months (range, 12-48 mo). Two patients had a follow-up of less than 12 months after surgery, and reinnervation was still in progress. In none of the patients who were operated on was tongue atrophy or impaired movement observed. Postoperative Facial Disability Index scores (mean, 71.8 +/- standard deviation [SD] 10.6) for physical functioning and social functioning (mean, 85.7 +/- SD 9.8) were increased for all patients when compared with preoperative scores (mean, 28.6 +/- SD 9.0; mean, 37.7 +/- SD 14.4, respectively). CONCLUSION: The facial-hypoglossal nerve transfer with direct coaptation of the intratemporal part of the facial nerve offers good functional results with low lingual morbidity and improved quality of life. The technique is straightforward, relatively simple, and should be considered as first option for reanimation of traumatic facial nerve lesions. 相似文献
12.
Case report of a very large ectasia of the urethra in a 9 years old boy without any organic conflict and without any neuro-urologic trouble. It could be a particular syndrome. 相似文献
13.
Annemieke C. Kole MD Omgo E. Nieweg MD PhD Robert J. van Ginkel MD Jan Pruim MD PhD Harald J. Hoekstra MD PhD Anne M. J. Paans PhD Willem Vaalburg PhD Dr. Heimen Schraffordt Koops MD PhD 《Annals of surgical oncology》1997,4(1):57-63
Background: It is often difficult to detect a local recurrence of soft-tissue sarcomas due to disturbance of the normal anatomy by previous
surgery and radiotherapy. The aim of this study was to assess the value of positron emission tomography (PET) with [18F]fluoro-2-deoxy-d-glucose (FDG) for detecting local recurrences.
Methods: In the period 1992–1995, 17 patients with proven or suspected local recurrence of soft-tissue sarcoma were examined using
FDG-PET. Fifteen of these patients were ultimately proven to have a recurrence.
Results: Recurrence was visualized in 14 patients (93%). Small tumors (maximum diameter 0.5 cm) were as easily visible as large lesions
(maximum diameter 20 cm). In one patient the PET scan was positive, but the recurrence could not be proven histologically.
Recurrence was proven 1 year later. A recurrent low-grade liposarcoma was not visualized. The two patients with benign lesions
had a negative PET scan. The mean glucose metabolic rate was calculated to be 13.2 μmol/100 g/min (range 1.9–28.4). A correlation
was found between the histological malignancy grade and the metabolic rate (p<0.05; Kruskal-Wallis).
Conclusion: PET with FDG is a useful addition to the diagnostic armamentarium for detecting local recurrence of soft-tissue sarcomas
and provides an indication of the malignancy grade of the recurrent lesion.
Presented at the 47th Annual Meeting of The Society for Surgical Oncology, Houston, Texas, March 17–20, 1994. 相似文献
14.
Coronary vasomotion in patients with syndrome X: evaluation with positron emission tomography and parametric myocardial perfusion imaging 总被引:1,自引:1,他引:0
Joan G. Meeder Paul K. Blanksma Ernst E. van der Wall Antoon T. M. Willemsen Jan Pruim Rutger L. Anthonio Richard M. de Jong Willem Vaalburg Kong I. Lie 《European journal of nuclear medicine and molecular imaging》1997,24(5):530-537
The aim of this study was to elucidate further the causative mechanism of abnormal coronary vasomotion in patients with syndrome X. In patients with syndrome X, defined as angina pectoris and documented myocardial ischaemia during stress testing with normal findings at coronary angiography, abnormal coronary vasomotion of either the micro- or the macrocirculation has been suggested as the causative mechanism. Accordingly, we evaluated endothelial function, vasodilator reserve, and perfusion heterogeneity in these patients. Twenty-five patients with syndrome X (definitely normal coronary arteriogram, group A), 15 patients with minimal coronary artery disease (group B) and 21 healthy volunteers underwent [13N]ammonia positron emission tomography at rest, during cold pressor stimulation (endothelial function) and during dipyridamole stress testing (vasodilator reserve). Heterogeneity of myocardial perfusion was analysed by parametric polar mapping using a 480-segment model. In both patient groups, resting perfusion was increased compared to the normal subjects: group A, 127±31 ml·min–1·100 g–1; group B, 124±30 ml·min–1·100 g–1 normal subjects, 105±21 ml·min–1·100 g–1 (groups A and B vs normals,P<0.05). These differences were abolished after correction for rate-pressure product. During cold pressor stimulation, the perfusion responses (ratio of cold pressor perfusion to resting perfusion) were similar among the patients and the control subjects (group A, 1.20±0.23; group B, 1.24±0.22; normal subjects, 1.23±0.14). Likewise, during dipyridamole stress testing, perfusion responses were similar among the three groups (group A, 2.71±0.67; group B, 2.77±1.29; normal subjects, 2.91±1.04). In group A the heterogeneity of resting perfusion, expressed as coefficient of variation, was significantly different from the volunteers (20.1±4.5 vs 17.0±3.0,P<0.05). In group B (coefficient of variation 19.4±3.9) the difference from normal volunteers was not significant. In this study, patients with syndrome X and patients with minimal coronary artery disease showed normal perfusion responses during cold pressor stimulation and dipyridamole stress testing. Our findings therefore suggest that endothelial dysfunction and impaired vasodilator reserve are of no major pathophysiological relevance in patients with syndrome X. Rather, other mechanisms such as increased sympathetic tone and focal release of vasoactive substances may play a role in the pathogenesis of syndrome X. 相似文献
15.
Bis[di-n-butyl (4-aminosalicylato)tin] oxide [NSC: 628561] (compound 1), bis [diphenyl(4-aminosalicylato)tin] oxide [NSC: 628562] (compound 2), and six other analogous compounds of the type [n-Bu2 (XYZ-C6H2COO)Sn]2O (compounds 3 to 8), were tested in vitro at the National Cancer Institute, Bethesda, Maryland, USA, for cytotoxic activity against a series of human cell lines. Compounds 1, 6 and 8 score globally satisfactorily since four of the five relevant sensitivity or selectivity parameters, DGI50, DTGI or DLC50, DH and MGDH, are statistically significant. Compounds 3 and 7 are less satisfactory because only three such parameters are statistically significant. For compound 2, only two of the parameters are significant. 相似文献
16.
SYNOPSIS
Relationships between precipitating factors in the pathogenesis of migraine were studied in a sample of 217 migraineurs. The most frequently cited triggers were the menstrual cycle (51.5% of the women), alcoholic beverages (51.6%) and emotional or psychic stress (48.8%). Analysis of 4 subgroups of patients, i.e. those with only one of these 3 triggers or with none of these (controls), showed that alcohol-susceptible patients reported significantly (p<0.001) more alimentary triggers than the controls. A similar phenomenon was found in patients with menstrual-cycle related migraine, but in this group the difference with the controls fell short of reaching statistical significance. A further analysis showed that menstrual migraine attacks are more frequently preceded by depressive symptoms than other migraine attacks.
It is suggested that the gut of certain migraineurs may be unduly permeable, either intrinsically or extrinsically (e.g. under the influence of alcohol). In addition, in some patients with menstrual migraine, a depressive episode, associated with the menstrual period, may facilitate the development of a migraine attack. 相似文献
Relationships between precipitating factors in the pathogenesis of migraine were studied in a sample of 217 migraineurs. The most frequently cited triggers were the menstrual cycle (51.5% of the women), alcoholic beverages (51.6%) and emotional or psychic stress (48.8%). Analysis of 4 subgroups of patients, i.e. those with only one of these 3 triggers or with none of these (controls), showed that alcohol-susceptible patients reported significantly (p<0.001) more alimentary triggers than the controls. A similar phenomenon was found in patients with menstrual-cycle related migraine, but in this group the difference with the controls fell short of reaching statistical significance. A further analysis showed that menstrual migraine attacks are more frequently preceded by depressive symptoms than other migraine attacks.
It is suggested that the gut of certain migraineurs may be unduly permeable, either intrinsically or extrinsically (e.g. under the influence of alcohol). In addition, in some patients with menstrual migraine, a depressive episode, associated with the menstrual period, may facilitate the development of a migraine attack. 相似文献
17.
Ruprecht Nitschke Charles Pratt Michael Harris Jeffrey Krischer Teresa J. Vietti Holcombe Grier Willem Kamps Stuart Toledano 《Investigational new drugs》1992,10(2):93-96
CHIP (325 mg/M2), a second generation cisplatin derivative, was administered intravenously every 3 weeks to 85 pediatric patients with recurrent sarcomas (19), osteosarcomas (20), neuroblastoma (23), germ cell tumors (10), and other malignant tumors (7). Thirty-eight of them had been previously exposed to cisplatin. Partial remissions were only observed in 3 of 23 (13% SE=7%) patients having neuroblastoma. Severe thrombocytopenia (65%) and neutropenia (35%) were the dose limiting factors. 相似文献
18.
B. Willem Schreurs Pieter T. J. Spierings Rik Huiskes Tom J. J. H. Slooff 《Acta orthopaedica》1988,59(4):403-409
We investigated four acrylic cement preparation techniques for their effects on cement porosity: hand mixing, pressurization in a pneumatic pistol, centrifugation, and vacuum mixing. All the techniques were tested on three types of cement with different viscosity characteristics. The best results were obtained with vacuum mixing using a newly designed experimental system, yielding porosity reductions of 60-80 percent relative to hand mixing. Vacuum mixing with a commercial system was also effective, but to a somewhat lesser extent.
Pressurization and centrifugation had no substantial effect on the overall porosity. Centrifugation led to considerable nonuniformity in the distribution of pores and additives. 相似文献
Pressurization and centrifugation had no substantial effect on the overall porosity. Centrifugation led to considerable nonuniformity in the distribution of pores and additives. 相似文献
19.
Alan G. Fraser Peter T. Buser Jeroen J. Bax Willem R. Dassen Petros Nihoyannopoulos Jürg Schwitter Juhani M. Knuuti Martin Höher Frank Bengel András Szatmári 《European journal of nuclear medicine and molecular imaging》2006,33(8):955-959
Advances in medical imaging now make it possible to investigate any patient with cardiovascular disease using multiple methods which vary widely in their technical requirements, benefits, limitations and costs. The appropriate use of alternative tests requires their integration into joint clinical diagnostic services where experts in all methods collaborate. This statement summarises the principles that should guide developments in cardiovascular diagnostic services.This paper is published simultaneously in the European Heart Journal (2006;27:1750–1753) and in the European Journal of Echocardiography (2006;7:268–273). 相似文献
20.
Bastiaan R Klarenbeek Alexander AFA Veenhof Elly SM de Lange Willem A Bemelman Roberto Bergamaschi Piet Heres Antonio M Lacy Wim T van den Broek Donald L van der Peet Miguel A Cuesta 《BMC surgery》2007,7(1):16