全文获取类型
收费全文 | 205637篇 |
免费 | 4910篇 |
国内免费 | 470篇 |
专业分类
耳鼻咽喉 | 2922篇 |
儿科学 | 7734篇 |
妇产科学 | 6187篇 |
基础医学 | 26495篇 |
口腔科学 | 5946篇 |
临床医学 | 16393篇 |
内科学 | 37137篇 |
皮肤病学 | 4569篇 |
神经病学 | 12452篇 |
特种医学 | 11022篇 |
外国民族医学 | 97篇 |
外科学 | 30998篇 |
综合类 | 1266篇 |
一般理论 | 15篇 |
预防医学 | 17412篇 |
眼科学 | 5101篇 |
药学 | 14015篇 |
2篇 | |
中国医学 | 148篇 |
肿瘤学 | 11106篇 |
出版年
2018年 | 3776篇 |
2017年 | 4062篇 |
2016年 | 3345篇 |
2015年 | 5114篇 |
2014年 | 4625篇 |
2013年 | 3889篇 |
2012年 | 10567篇 |
2011年 | 5492篇 |
2010年 | 2622篇 |
2009年 | 4233篇 |
2008年 | 2766篇 |
2007年 | 3488篇 |
2006年 | 3772篇 |
2005年 | 11856篇 |
2004年 | 13325篇 |
2003年 | 8852篇 |
2002年 | 4075篇 |
2001年 | 4433篇 |
2000年 | 1760篇 |
1999年 | 5961篇 |
1998年 | 650篇 |
1995年 | 478篇 |
1992年 | 6942篇 |
1991年 | 7166篇 |
1990年 | 7413篇 |
1989年 | 7012篇 |
1988年 | 6528篇 |
1987年 | 6302篇 |
1986年 | 6006篇 |
1985年 | 5318篇 |
1984年 | 3685篇 |
1983年 | 2984篇 |
1982年 | 1088篇 |
1981年 | 874篇 |
1980年 | 920篇 |
1979年 | 3883篇 |
1978年 | 2411篇 |
1977年 | 1814篇 |
1976年 | 1594篇 |
1975年 | 2502篇 |
1974年 | 3132篇 |
1973年 | 2761篇 |
1972年 | 2769篇 |
1971年 | 2751篇 |
1970年 | 2565篇 |
1969年 | 2472篇 |
1968年 | 2251篇 |
1967年 | 2170篇 |
1966年 | 1911篇 |
1965年 | 1145篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Consideration is given to the technique and the device for detecting water amount linked to high-molecular compounds presenting the base for blood substitutes. The device is simple in use, outputs reproducible data comparable to the well known results (e.g. for polyglucine). It should be recommended for evaluating hemodynamic parameters of newly developed blood substitutes. 相似文献
992.
F B?umer 《Zentralblatt für Chirurgie》1987,112(8):485-490
A retrospective study was conducted into 136 patients who had received surgical treatment for perforated gastroduodenal ulcers, with the view to establishing postoperative lethality and morbidity (comparing simple suturing with definitive ulcer surgery). Factors of relevance to prognosis were taken into consideration, including age of patients, number of concomitant diseases, time from perforation to surgery, presence of peritonitis, ulcer location, and length of ulcer history. 相似文献
993.
Matthias Feichtinger Reingard Maria Aigner Gert Santler Hans K?rcher 《Journal of cranio-maxillo-facial surgery》2007,35(6-7):322-328
INTRODUCTION: Surgery based on computed tomography (CT) data is becoming increasingly important in the head and neck region. The technique for hardware fusion between positron emission tomography (PET) and computed tomography (CT) has only been established commercially in the last 4 years. The advantages over CT alone are obvious. The surgeon is simultaneously provided with a map of anatomical as well as of functional (metabolic) details. The fused images offer improved localization of malignant lesions and improved targeting of biopsy, especially for small lesions. PURPOSE: A new technique for image-guided tumour localization for maxillofacial surgery based on PET/CT-image fusion is described. PATIENT AND METHOD: A 78-year-old woman was admitted to this department with a tumour of the skull base. Three dimensional fusion of computed CT with positron PET images on a commercially available navigation system is described. After patient-to-image registration, a high-resolution endoscope was calibrated intraoperatively. Image-guided biopsy specimens were taken under direct visual control. CONCLUSION: PET/CT-image fusion proved extremely helpful to navigate the endoscope to the target lesion and to identify the tumour. 相似文献
994.
With regard to disturbances of the iron metabolism, porphyria cutanea tarda (PCT) is most frequently accompanied by liver siderosis. In 74 out of 88 patients suffering from PCT (84%), we found histochemical evidence of liver siderosis. These patients showed a significantly higher incidence of HLA A3--which has been proved to be associated with hemochromatosis--than those without liver siderosis (39.2% vs. 7.1%). With part of the PCT patients, disorders of the iron metabolism related to the HLA system (A3) might contribute to the manifestation of the disease. We discuss PCT as the result of the combined action of several predisposing genetic markers and exogenic factors. 相似文献
995.
996.
997.
Hemorheology in surgery--a review 总被引:1,自引:0,他引:1
The rheological behavior of blood and its components under physiologic and pathophysiologic conditions is reviewed, with a focus on the type and extent of pathohemorheological changes in surgical patients during hospitalization and thereafter, as well as their clinical consequences with regard to thromboembolic complications. During the operation and the postoperative period various hemorheological and hemostasiological alterations acquire clinical significance: 1. hyperreagibility of platelets with increased aggregation and adhesion tendency 2. changes in fibrinogen, albumin, and globulin concentrations, which affect viscosity and red cell aggregation 3. impairment of red cell deformability 4. increase in clotting factors 5. disturbance of fibrinolysis characterized by diminution of plasmatic plasmin and increase in antiplasmin activity In addition, anesthetic techniques have also been shown to affect hemorheological and hemostasiological parameters. The complex pattern of pathohemorheological and hemostasiological changes shows that thromboembolism in the course of surgical interventions is provoked by multifactorial disorders. Thrombosis prevention should, therefore, counteract both hemorheological and hemostasiological disturbances. Since pathohemorheological and pathohemostasiological changes are already detectable before, and increase during operation, preventive measures should start before the surgical intervention to obtain maximum benefit. Therapeutic possibilities for the avoidance of these multifactorial disturbances are discussed with particular reference to pentoxifylline, which satisfies the complex requirements of a hemorheologically and hemostasiologically active therapeutic agent. 相似文献
998.
999.
Salla disease variants. Sialoylaciduric encephalopathy with increased sialidase activity in two non-Finnish children 总被引:2,自引:0,他引:2
V Ylitalo B Hagberg J Rapola J E M?nsson L Svennerholm G Sanner B Tonnby 《Neuropediatrics》1986,17(1):44-47
The case reports of two Swedish girls with initially pseudostationary clinical pictures, one simulating ataxic and the other dyskinetic cerebral palsy, are presented. It was eventually revealed that they had a slowly progressive encephalopathy with pronounced gross motor disability and signs of severe dyskinesia, but only mild intellectual delay. Electron microscopy of skin biopsies showed a picture identical to that in Salla disease. They had a moderately increased 5-10 fold urinary free sialic acid excretion, increased sialidase activity in lymphocytes but normal activity in cultured fibroblasts. These two Swedish cases represent variants of Salla disease, a group of conditions with probable genetic heterogeneity. 相似文献
1000.