全文获取类型
收费全文 | 3042052篇 |
免费 | 239664篇 |
国内免费 | 7892篇 |
专业分类
耳鼻咽喉 | 43395篇 |
儿科学 | 96167篇 |
妇产科学 | 82460篇 |
基础医学 | 430344篇 |
口腔科学 | 87453篇 |
临床医学 | 279123篇 |
内科学 | 588375篇 |
皮肤病学 | 64343篇 |
神经病学 | 251432篇 |
特种医学 | 120321篇 |
外国民族医学 | 1148篇 |
外科学 | 456176篇 |
综合类 | 76562篇 |
现状与发展 | 5篇 |
一般理论 | 1292篇 |
预防医学 | 246041篇 |
眼科学 | 71736篇 |
药学 | 226279篇 |
30篇 | |
中国医学 | 7317篇 |
肿瘤学 | 159609篇 |
出版年
2018年 | 32260篇 |
2017年 | 24936篇 |
2016年 | 27680篇 |
2015年 | 31486篇 |
2014年 | 44733篇 |
2013年 | 67504篇 |
2012年 | 90401篇 |
2011年 | 95556篇 |
2010年 | 56788篇 |
2009年 | 53731篇 |
2008年 | 89647篇 |
2007年 | 95216篇 |
2006年 | 96260篇 |
2005年 | 93495篇 |
2004年 | 90033篇 |
2003年 | 86793篇 |
2002年 | 84945篇 |
2001年 | 138392篇 |
2000年 | 143208篇 |
1999年 | 120903篇 |
1998年 | 35426篇 |
1997年 | 32139篇 |
1996年 | 31696篇 |
1995年 | 30716篇 |
1994年 | 28816篇 |
1993年 | 26716篇 |
1992年 | 97489篇 |
1991年 | 94480篇 |
1990年 | 91534篇 |
1989年 | 88214篇 |
1988年 | 81528篇 |
1987年 | 80661篇 |
1986年 | 76208篇 |
1985年 | 73035篇 |
1984年 | 55370篇 |
1983年 | 47218篇 |
1982年 | 28810篇 |
1981年 | 25694篇 |
1979年 | 52017篇 |
1978年 | 36754篇 |
1977年 | 31077篇 |
1976年 | 29302篇 |
1975年 | 30775篇 |
1974年 | 37912篇 |
1973年 | 36083篇 |
1972年 | 33670篇 |
1971年 | 31259篇 |
1970年 | 29219篇 |
1969年 | 27230篇 |
1968年 | 24881篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
A. G. D. Maran J. A. Wilson M. N. Gaze 《European archives of oto-rhino-laryngology》1993,250(3):127-132
Summary Squamous cell carcinoma of the head and neck is a disease predominantly of males and is due to a variety of known environmental irritants, notably cigarette smoke. Dietary, viral and immunological factors may also be relevant. Head and neck squamous cancers express epidermal growth factor receptors and some show weak levels of oestrogen receptor activity, but a reliable serum marker of tumour burden remains to be identified. The prognosis is found to be less favourable in females, in those with advanced T stage, in association with multiple node involvement, especially where extracapsular spread is present and where the T4/T8 ratio is elevated. Administration of heterologous blood during therapy may also have an adverse effect on prognosis. Interested clinicians must remember that most cases are preventable.
Correspondence to: A.G.D. Maran 相似文献
994.
995.
A E van der Merwe F J Mattheyse M Bedford P D van Helden D J Rossouw 《Burns : journal of the International Society for Burn Injuries》1990,16(3):193-197
Cultured keratinocytes were used as allografts on burn wounds in two patients. In both patients successful covering of the wounds was obtained. DNA fingerprinting of the epidermis covering the wounds 21 days later showed that the cultured keratinocytes were replaced by the patients' cells. 相似文献
996.
Primary extraosseous osteogenic sarcoma of the mediastinum: clinical, pathologic, and radiologic correlation 总被引:1,自引:0,他引:1
R W Tarr T Kerner B McCook D L Page E P Nance J J Kaye 《Southern medical journal》1988,81(10):1317-1319
We have presented a rare case of primary involvement of the anterior mediastinum by osteogenic sarcoma in which CT was useful in demonstrating calcium within the mass, and in distinguishing the mass from surrounding bony structures. Although rare, extraosseous osteogenic sarcoma should be included in the differential diagnosis of a calcified anterior mediastinal mass. 相似文献
997.
Rapid reorganization of adult rat motor cortex somatic representation patterns after motor nerve injury. 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
J N Sanes S Suner J F Lando J P Donoghue 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(6):2003-2007
The potential for peripheral nerve injury to reorganize motor cortical representations was investigated in adult rats. Maps reflecting functional connections between the motor cortex and somatic musculature were generated with intracortical electrical stimulation techniques. Comparison of cortical somatotopic maps obtained in normal rats with maps generated from rats with a facial nerve lesion indicated that the forelimb and eye/eyelid representations expanded into the normal vibrissa area. Repeated testing from an electrode placed chronically in the motor cortex showed a shift from vibrissa to forelimb within hours after facial nerve transection. These comparatively quick changes in motor cortex representation pattern suggest that synaptic relations between motor cortex and somatic musculature are continually reshaped in adult mammals. 相似文献
998.
CT- or sonography-guided biopsy of the liver in the presence of ascites: frequency of complications 总被引:1,自引:0,他引:1
F B Murphy K P Barefield H V Steinberg M E Bernardino 《AJR. American journal of roentgenology》1988,151(3):485-486
The presence of ascites has been considered a contraindication to percutaneous biopsy of the liver. To determine the validity of this assumption, we performed percutaneous biopsies of the liver under CT or sonographic guidance in 28 patients who had ascites and in 28 patients who did not have ascites and compared the complication rates in the two groups. Twenty-two patients (79%) in the group with ascites and 19 patients (68%) in the group without ascites had biopsies to determine the cause or extent of chronic liver disease. The remainder were oncologic patients who had biopsies to determine the cause of a focal hepatic mass. The complication rate in the patients who had ascites (32%) was less than that in the patients who did not have ascites (43%) (the difference did not reach statistical significance, p less than .30). In the ascites group, complications included transient hypotension (five patients), a mild-to-moderate fall in hematocrit (three patients), and a small leak of ascites from the biopsy site (one patient). In the control group, minor complications included transient hypotension (three patients), a mild-to-moderate fall in hematocrit (seven patients), and a small subcapsular hematoma (one patient). One major complication occurred in the control group: a patient required a blood transfusion because of the fall in his hematocrit. We conclude that the complication rate in liver biopsies guided by CT or sonography in the presence of ascites is not higher than similar biopsies done in the absence of ascites. Ascites should not be considered a contraindication for performing such biopsies. 相似文献
999.
1000.
M Parry-Billings B Leighton G D Dimitriadis J Bond E A Newsholme 《Biochemical pharmacology》1990,40(5):1145-1148
The effects of physiological and pathological concentrations of glucocorticoids were investigated using the glucocorticoid antagonist RU486 and the synthetic glucocorticoid dexamethasone, respectively. The effects of these treatments on the concentrations of glutamine and other amino acids in skeletal muscle and plasma and on the rates of release of glutamine and alanine from incubated preparations of skeletal muscle of the rat were investigated. Dexamethasone treatment increased the concentration of glutamine and the rate of release of this amino acid from incubated soleus muscle preparations. This treatment decreased the concentration of glutamine in both gastrocnemius and EDL muscles, but was without effect on the rate of glutamine release from EDL muscles. In contrast, administration of the glucocorticoid antagonist RU486 decreased the rate of glutamine release from muscle. It is concluded that glucocorticoids have marked effects on the metabolism of glutamine by skeletal muscle per se and that these hormones may be important in the control of the rate of glutamine release from muscle in both physiological and pathological conditions. 相似文献