全文获取类型
收费全文 | 6063篇 |
免费 | 408篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 122篇 |
儿科学 | 162篇 |
妇产科学 | 113篇 |
基础医学 | 836篇 |
口腔科学 | 69篇 |
临床医学 | 742篇 |
内科学 | 1591篇 |
皮肤病学 | 56篇 |
神经病学 | 500篇 |
特种医学 | 151篇 |
外国民族医学 | 1篇 |
外科学 | 1130篇 |
综合类 | 15篇 |
一般理论 | 3篇 |
预防医学 | 316篇 |
眼科学 | 94篇 |
药学 | 278篇 |
中国医学 | 4篇 |
肿瘤学 | 324篇 |
出版年
2023年 | 43篇 |
2022年 | 80篇 |
2021年 | 220篇 |
2020年 | 107篇 |
2019年 | 208篇 |
2018年 | 222篇 |
2017年 | 137篇 |
2016年 | 137篇 |
2015年 | 190篇 |
2014年 | 217篇 |
2013年 | 312篇 |
2012年 | 423篇 |
2011年 | 408篇 |
2010年 | 240篇 |
2009年 | 201篇 |
2008年 | 355篇 |
2007年 | 333篇 |
2006年 | 339篇 |
2005年 | 295篇 |
2004年 | 272篇 |
2003年 | 259篇 |
2002年 | 225篇 |
2001年 | 114篇 |
2000年 | 108篇 |
1999年 | 111篇 |
1998年 | 40篇 |
1997年 | 49篇 |
1996年 | 20篇 |
1995年 | 19篇 |
1994年 | 19篇 |
1993年 | 22篇 |
1992年 | 75篇 |
1991年 | 63篇 |
1990年 | 44篇 |
1989年 | 51篇 |
1988年 | 43篇 |
1987年 | 42篇 |
1986年 | 64篇 |
1985年 | 47篇 |
1984年 | 45篇 |
1983年 | 24篇 |
1981年 | 18篇 |
1979年 | 23篇 |
1978年 | 18篇 |
1977年 | 18篇 |
1976年 | 17篇 |
1974年 | 22篇 |
1973年 | 24篇 |
1972年 | 21篇 |
1971年 | 23篇 |
排序方式: 共有6507条查询结果,搜索用时 15 毫秒
1.
José A. Lorente Pablo Cardinal-Fernández Diego Muñoz Fernando Frutos-Vivar Arnaud W. Thille Carlos Jaramillo Aida Ballén-Barragán José M. Rodríguez Oscar Peñuelas Guillermo Ortiz José Blanco Bruno Valle Pinheiro Nicolás Nin María del Carmen Marin Andrés Esteban Taylor B. Thompson 《Intensive care medicine》2015,41(11):1921-1930
2.
N Jastrow E Antonelli R Robyr O Irion M Boulvain 《Ultrasound in obstetrics & gynecology》2006,27(4):420-424
OBJECTIVE: To evaluate the reproducibility of sonographic measurement of the lower uterine segment in pregnant women at term. METHODS: Two independent observers performed transabdominal sonography on 129 women between 36 and 38 weeks of gestation who had had a previous Cesarean section. Sonography was performed when the patients had a full and a half-full bladder; in 100 patients, the measurements were also performed transvaginally, with the patients having an empty bladder. Agreement was quantified by the intraclass correlation coefficient and, using a cut-off of 3.5 mm, by the kappa coefficient. RESULTS: The intraobserver agreement was generally high (intraclass correlation coefficient > 0.90). The interobserver agreement was higher on transvaginal (intraclass correlation coefficient, 0.94) compared with transabdominal (0.70 and 0.84, with full and half-full bladder, respectively) ultrasound. The kappa coefficient was 0.75 transvaginally, compared with 0.34 and 0.54 using the transabdominal approach, with full and half-full bladder, respectively. CONCLUSION: The agreement between two observers for sonographic transvaginal measurement of the lower uterine segment can be considered good, compared with poor to moderate agreement using the transabdominal approach. 相似文献
3.
P Peretti-Viton D Margain O Arnaud A M Perez-Castillo N Graziani 《Journal of neuroradiology. Journal de neuroradiologie》1991,18(2):173-188
Three types of lymphoma of the central nervous system are known: primary non-Hodgkin's malignant lymphoma (NHML), secondary NHML and neurological lesions of Hodgkin's disease. NHML's are rare tumours, often associated with immunodeficiency and presenting predominantly as neuropsychological disorders. In this study 8 patients were explored by CT and MRI, with pathological confirmation. None of our patients had AIDS. The most typical neuroradiological image of this type of tumour is that of a large and intensely contrast-enhanced tumoral mass which is often multifocal and periventricular with infiltration of the subarachnoidal spaces and leptomeninges. Mass effect and perifocal oedema are less pronounced than expected with tumours of that size. NHML's may totally regress under corticosteroid therapy. This tumour of obscure aetiology must be recognized as it is now increasingly frequent. 相似文献
4.
C L Maini R Antonelli Incalzi M G Bonetti G Valle 《European journal of nuclear medicine》1986,12(2):60-64
A total of 131 patients with old (over 6 months) myocardial infarction (MI) and 18 normal subjects underwent equilibrium radionuclide angiocardiography at rest (rERNA). The following rERNA parameters were assessed: left ventricular ejection fraction (LVEF), peak ejection rate (PER), peak filling rate (PFR), regional wall motion and a left ventricular size index. The patients with old MI were divided into four groups (I to IV) according to increasing left ventricular (LV) size, and the behaviour of the numerical parameters (LVEF, PER, PFR) was evaluated in each group. LVEF proved to be the most sensitive numerical parameter of overall LV performance. PFR decreased significantly from group I to group III but not from group III to group IV, suggesting that for extreme degrees of left ventricular enlargement some compensatory mechanism acts to prevent a too large fall in LV compliance. The effects of the site of the previous MI on LV performance were also evaluated. Both LV size and performance were least affected by postero-inferior MI. The LVEF was, however, a better predictor of LV size than the site of the MI. 相似文献
5.
D S Rao R Antonelli K R Kane J E Kuhn C Hetnal 《Henry Ford Hospital medical journal》1991,39(1):41-44
Coexistent primary hyperparathyroidism and monoclonal gammopathy, although rare, has been reported previously by a number of investigators. We report four patients with such an occurrence who were seen between 1976 and 1988. Another patient with primary hyperparathyroidism also had multiple myeloma and was in remission for 12 years. These patients represent approximately 1% of the 386 patients with primary hyperparathyroidism seen during the same 12-year period. Although several mechanisms have been proposed to explain this concurrence, we believe it is the result of a chance occurrence. A review of the literature, an estimate of the chance occurrence of coincidental monoclonal gammopathy, benign or malignant, in patients with primary hyperparathyroidism, and some practical implications of this interesting coexistence are presented. 相似文献
6.
HYPOTHESIS: Irrigation of the mastoid with a quinolone antibiotic-steroid solution may mitigate hearing loss caused by iatrogenic semicircular canal injury in the presence of Pseudomonas aeruginosa (PA) otitis media (OM). BACKGROUND: Studies have shown the cochlea to be more vulnerable to semicircular canal transection (SCT)-related hearing loss in the presence of PA OM. Prophylactic systemic antibiotics and steroids may decrease this hearing loss, but SCT is usually not planned. The aim of this study was to determine if irrigation with ciprofloxacin-dexamethasone (cipro-dex) could improve hearing outcomes following SCT in PA OM. METHODS: PA OM was induced in 28 animals. After three to five days, unilateral SCT was performed in each animal, with sham SCT on the contralateral ear. At surgery, half of the animals (n = 14) underwent irrigation of the both mastoid bullae with cipro-dex; the second group of animals (n = 14) underwent irrigation of the bullae with sterile saline. Auditory thresholds were obtained immediately prior to SCT and 7-10 days after SCT. RESULTS: SCT ears treated with cipro-dex showed a mean click threshold improvement of 4.6 dB from pre-transection to 7-10 days post-transection, whereas thresholds in the SCT ears treated with saline worsened by 7.5 dB (p = 0.15). CONCLUSION: Irrigation of the guinea pig bulla with cipro-dex following SCT in the setting of PA OM appears safe and may yield beneficial effects on hearing. 相似文献
7.
8.
9.
Alterations in glycosaminoglycans and their receptors have been associated with changes in cell proliferation during development, wound healing, regeneration, and remodeling. We have previously found a differential effect of hyaluronic acid on the attachment of vascular cells in vitro; endothelial cell (EC) attachment was improved on hyaluronic acid-coated substrates, whereas that of smooth muscle cells (SMC) was reduced (Orlidge and D'Amore, 1986). To determine if hyaluronic acid binding sites are involved in these different substrate preferences, we have studied specific hyaluronic acid binding to cultured bovine aortic EC and SMC. Since very large numbers of cells are required for these binding assays (3 x 10(6)/data point), and since the level of hyaluronate binding to fixed and native SMC and EC was similar, fixed cells were used throughout this study. The effect of cell density on hyaluronic acid binding was investigated. No significant difference was observed between hyaluronic acid binding to sparse and high density SMC. On the other hand, a more than threefold elevation in specific hyaluronic acid binding was observed on low density EC when compared to binding on high density EC. Hyaluronic acid binding was found to be specific; excesses of heparan sulfate and chondroitin sulfate had no effect on the levels of specific binding. Finally, the effect of cell passage on SMC binding of hyaluronic acid was measured. Specific binding was measured from 1st to 12th passage cells and was found to increase with passage number so that by passage 12, hyaluronic acid binding was fourfold that of 1st passage cells. These data support the concept that SMC may become less differentiated upon continuous culture. Our results indicate quantitative changes in the level of hyaluronic acid binding to vascular cells as a function of their growth state. Further, these data correlate well with in vivo observations which suggest a role for hyaluronic acid in vascular development. 相似文献
10.
Laparoscopic hysterectomy 总被引:1,自引:0,他引:1
Michel Canis Gerard Mage Charles Chapron Arnaud Wattiez Jean Luc Pouly Maurice Antoine Bruhat 《Surgical endoscopy》1993,7(1):42-45
Summary Thirty-three patients were selected for laparoscopic hysterectomy and operated on in the Department of Obstetrics, Gynecology and Reproductive Medicine of Clermont-Ferrand University Hospital. Surgical techniques included blunt dissection with scissors and bipolar coagulation to achieve hemostasis. A case was considered successful when all the uterine vessels were treated by laparoscopy. Twenty-four cases were completed laparoscopically (72.7%). None of these patients had postoperative bleeding; 22 had an uneventful postoperative recovery. Nine procedures were converted to laparotomy (27.3%), five because of a difficult or unsatisfactory hemostasis. We conclude that in selected cases, a total hysterectomy can be performed safely by experienced laparoscopists. Further technological progress is necessary to make this procedure more acceptable. Its value as compared to the others will have to be demonstrated. 相似文献