全文获取类型
收费全文 | 21920篇 |
免费 | 1081篇 |
国内免费 | 60篇 |
专业分类
耳鼻咽喉 | 291篇 |
儿科学 | 632篇 |
妇产科学 | 421篇 |
基础医学 | 3234篇 |
口腔科学 | 618篇 |
临床医学 | 1957篇 |
内科学 | 4044篇 |
皮肤病学 | 512篇 |
神经病学 | 2141篇 |
特种医学 | 1183篇 |
外国民族医学 | 5篇 |
外科学 | 3176篇 |
综合类 | 83篇 |
一般理论 | 6篇 |
预防医学 | 1084篇 |
眼科学 | 536篇 |
药学 | 1515篇 |
中国医学 | 40篇 |
肿瘤学 | 1583篇 |
出版年
2023年 | 102篇 |
2022年 | 138篇 |
2021年 | 310篇 |
2020年 | 214篇 |
2019年 | 307篇 |
2018年 | 517篇 |
2017年 | 368篇 |
2016年 | 522篇 |
2015年 | 518篇 |
2014年 | 685篇 |
2013年 | 799篇 |
2012年 | 1324篇 |
2011年 | 1259篇 |
2010年 | 743篇 |
2009年 | 684篇 |
2008年 | 1160篇 |
2007年 | 1205篇 |
2006年 | 1241篇 |
2005年 | 1206篇 |
2004年 | 1171篇 |
2003年 | 1073篇 |
2002年 | 1036篇 |
2001年 | 500篇 |
2000年 | 513篇 |
1999年 | 445篇 |
1998年 | 230篇 |
1997年 | 142篇 |
1996年 | 140篇 |
1995年 | 117篇 |
1994年 | 121篇 |
1993年 | 87篇 |
1992年 | 215篇 |
1991年 | 190篇 |
1990年 | 202篇 |
1989年 | 181篇 |
1988年 | 187篇 |
1987年 | 194篇 |
1986年 | 179篇 |
1985年 | 181篇 |
1984年 | 140篇 |
1983年 | 144篇 |
1982年 | 88篇 |
1979年 | 162篇 |
1978年 | 105篇 |
1977年 | 97篇 |
1974年 | 80篇 |
1973年 | 95篇 |
1972年 | 76篇 |
1970年 | 78篇 |
1968年 | 83篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
J B?rsch R Luther J Preisler R Grünewald 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1988,43(5):119-121
We made a retrospective analysis with regard to the bacteriology and to the therapy of all patients with pleural empyema who were treated in the district lung hospital from 1. 1. 1982-31. 12. 1986. 92 patients had a non-specific empyema, only 3 patients had a specific empyema. All patients were aspirated repeatedly with physiological saline solution instillation and antimicrobic drug instillation in the pleural cavity. This daily aspiration and lavage was successfully in 65 patients. This method was ineffective in 30 patients. We treated 7 patients of this group by the closed drainage (rubber-tube drain), in 4 patients successfully. 3 patients had to be treated by a surgical operation. An insufficient obliteration of the cavity of empyema occurred also in 23 patients of this group. A systematic daily aspiration for a longer time led to regression of the cavity in 4 cases, whereas a surgical operation was necessary in 19 patients. We consider the daily aspiration and lavage as an effective method in patients in early acute stages of empyema. 相似文献
42.
Assisted reproduction (IVF/ICSI) is an established method for the treatment of infertility, though it entails a number of risks and limiting factors for the children and their families that really have to be considered and resolved. They also must be part of informative consultations before applying the selected (methods)/techniques. The following risks are of prime importance: 1. The increasing number of multiple pregnancies. Every multiple pregnancy has to be regarded as a complication of reproductive medicine: the rate of neonatal morbidity and mortality is higher compared to single pregnancies, and the emotional, logistic, and financial factors are significant for the concerned families. To limit these risks, it is preferable to perform only a single embryo transfer even though a lower rate of resulting pregnancies is to be expected. Of course it must be simultaneously provided that methods are developed and applied to transfer an embryo with high implantation potency. Based on existing/present results, the highest priority should not be given to pregnancy rates as high (as possible) but to the lowest possible complication rate for the infant with an acceptable pregnancy rate comparable to that achieved in fertile couples. 2. In assisted reproduction, the risk of fetal abnormalities seems to be elevated, but in some studies, according to the German IVF register, the selected method (ICSI) and other factors such as family abnormalities and environmental factors are relevant. Additional studies are required to clarify this subject and develop possible preventive strategies. 3. The children's psychomotoric development is normal as a rule. The risk of handicaps (retarded development spastic cerebral palsy) increases in accordance with the reduction of gestational period/age and the decrease of birth weight. This in turn is of particular significance in multiple pregnancies. 相似文献
43.
Thomas Verse Alexander Baisch Joachim T Maurer Boris A Stuck Karl H?rmann 《Otolaryngology--head and neck surgery》2006,134(4):571-577
OBJECTIVE: To determine the efficacy of a new multilevel surgical protocol for obstructive sleep apnea (OSA). STUDY DESIGN AND SETTING: Sixty patients with moderate to severe OSA because of multilevel pharyngeal obstruction were enrolled into this prospective, controlled clinical trial after clinical examination, endoscopy, and polysomnography. Surgery included uvulaflap, tonsillectomy, hyoid suspension, and radiofrequency treatment of the tongue base (group A). A second group did not receive hyoid suspension (group B). In both groups, nasal surgery was performed if necessary. Polysomnography and Epworth Sleepines Scale (ESS) were recorded at baseline and 2 to 15 months after surgery. RESULTS: In group A, the mean apnea-hypopnea index (AHI) decreased significantly after surgery (38.9 +/- 20.0 vs 20.7 +/- 20.6, P < 0.0001), whereas in group B the AHI did not. All secondary variables (minimal oxygen saturation, mean oxygen saturation, arousal index), and the ESS significantly improved in group A with only changes in arousal index and ESS reaching levels of significance in group B. CONCLUSION: The presented protocol including the hyoid suspension proved to be effective in the treatment of OSA, whereas surgery without hyoid suspension was less successful. EBM rating: B-2b. 相似文献
44.
Subtraction and conventional radiography were evaluated for their diagnostic potential to assess interradicular bone lesions in the mandibular premolar region. Both conventional radiographs and subtraction images were interpreted by 10 observers. The receiver-operating characteristic (ROC) technique was used to compare the two techniques. The diagnostic validity was higher for the subtraction technique, both for lesions confined to cancellous bone and for lesions including the cortical bone, than for the conventional technique. For bone defects confined to cancellous bone the diagnostic accuracy was lower than those reported from periapical bone lesions irrespective of whether subtraction or conventional radiography was used. We conclude that subtraction radiography improves the detectability of bone lesions, shallow ones in particular. Lesions in the interradicular bone are more difficult to detect than those in the periapical bone. 相似文献
45.
46.
Eberhard Henze Gerhard Graf Malte Clausen Bertram Rail Rolf Weller Dieter Derichs Joachim Kreidler Peter Heidenreich F. Sitzmann Willi Ernst Adam 《European journal of nuclear medicine and molecular imaging》1990,16(2):97-101
The exact regional correlation of findings of facial bone scans, planar or SPECT, to dental orthopan X-ray films (OPT) is difficult because of the very different projection techniques. To improve correlative imaging in this regard a projection algorithm was developed that uses SPECT data of the skull for reconstructing an orthopan tomoscintigraphic projection. Fourteen conventional SPECT slices of the upper and lower jaws were obtained during bone scanning. All mandibular slices were superimposed resulting in a horseshoe shaped structure, which was marked by an ROI which was divided into segments. All 14 SPECT slices were then masked by this segmental ROI, thereby marking the teeth-carrying bone in all slices. The information from this horseshoe like ROI is then transformed into lines. Line by line arrangement results in an orthopan projection, the orthopan tomoscintigram. This new display allows 1:1 true scale superimposition with the X-ray OPT and markedly facilitates correlative imaging. 相似文献
47.
48.
49.
G Pakesch N Loimer J Grünberger D Pfersmann L Linzmayer S Mayerhofer 《Psychiatry research》1992,41(2):163-177
Reports available on the extent and incidence of cognitive deficits in human immunodeficiency virus (HIV-1) patients are variable. To assess the influence of drug abuse and psychiatric symptoms on the extent of the cognitive deficit, we examined 42 drug-addicted HIV-1 patients and compared them with a group of seronegative drug addicts (n = 31) as well as with a group of healthy controls (n = 50), using a psychometric test battery and standardized psychiatric scales. We found no significant difference in the extent and incidence of cognitive deficits in the group of HIV-1 patients as compared with the seronegative drug addicts. Both groups, however, differed from the normal population group. Remarkable depressive symptoms were found in the HIV-1 infected patient group. We assume that long-term drug abuse contributes markedly to the cognitive deficit of HIV-1 patients, which is further influenced by depressive symptoms. 相似文献
50.
Dr. J. Menck Ch. Bertram J. Grüber W. Lierse 《European journal of trauma and emergency surgery》1992,18(6):321-324
The design of the tibial medullary nail can be improved in order to preserve intraosseus vessels by osteosynthesis of the tibia. The nutrient artery of the human tibia enters the compacta in an average height of 33% dorsally and is leaving it in a height of 50% of the tibial length. In the medullary cavity the vessel splits up. The main branch continues the distal course on the dorsal/dorsolateral side of the medullary cavity (endosteal). In the distal diaphysis this endosteal vessel is of great importance, since the periosteal blood supply in this region with high incidence of pseudarthrosis is guaranteed only by branches of the anterior tibial artery. Using a new unreamed tibial nail, which is flattened dorsally, it is possible to preserve the endostal main artery of the tibia. 相似文献