全文获取类型
收费全文 | 4467篇 |
免费 | 254篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 85篇 |
妇产科学 | 58篇 |
基础医学 | 626篇 |
口腔科学 | 99篇 |
临床医学 | 257篇 |
内科学 | 1171篇 |
皮肤病学 | 397篇 |
神经病学 | 207篇 |
特种医学 | 145篇 |
外科学 | 937篇 |
综合类 | 16篇 |
预防医学 | 102篇 |
眼科学 | 36篇 |
药学 | 187篇 |
中国医学 | 11篇 |
肿瘤学 | 419篇 |
出版年
2023年 | 25篇 |
2022年 | 73篇 |
2021年 | 133篇 |
2020年 | 73篇 |
2019年 | 89篇 |
2018年 | 135篇 |
2017年 | 96篇 |
2016年 | 94篇 |
2015年 | 127篇 |
2014年 | 159篇 |
2013年 | 178篇 |
2012年 | 308篇 |
2011年 | 315篇 |
2010年 | 177篇 |
2009年 | 157篇 |
2008年 | 259篇 |
2007年 | 271篇 |
2006年 | 275篇 |
2005年 | 262篇 |
2004年 | 260篇 |
2003年 | 292篇 |
2002年 | 279篇 |
2001年 | 47篇 |
2000年 | 50篇 |
1999年 | 55篇 |
1998年 | 68篇 |
1997年 | 57篇 |
1996年 | 49篇 |
1995年 | 39篇 |
1994年 | 42篇 |
1993年 | 32篇 |
1992年 | 29篇 |
1991年 | 38篇 |
1990年 | 12篇 |
1989年 | 17篇 |
1988年 | 27篇 |
1987年 | 14篇 |
1986年 | 17篇 |
1985年 | 19篇 |
1984年 | 12篇 |
1983年 | 11篇 |
1982年 | 12篇 |
1981年 | 8篇 |
1980年 | 8篇 |
1979年 | 10篇 |
1978年 | 8篇 |
1976年 | 5篇 |
1974年 | 10篇 |
1972年 | 6篇 |
1971年 | 5篇 |
排序方式: 共有4764条查询结果,搜索用时 31 毫秒
31.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献
32.
Chromosomal Mapping of Genetic Locus Associated with Thymus-size Enlargement in BUF/Mna Rats 总被引:2,自引:1,他引:1
Yoshiki Murakumo Masahide Takahashi Atsushi Arakawa Mitsuhiro Saito Hiroyuki Amo Hideki Katoh Mutsushi Matsuyama 《Cancer science》1993,84(8):838-840
The thymoma-prone rat of the BUF/Mna strain is a useful model for human thymoma. In this strain thymoma development is regulated by a single autosomal susceptible gene, Tsr-1. At pre-thymoma age, BUF/Mna rats have extremely large thyrauses, when compared to those of other strains of rats. Genetic studies in crosses between BUF/Mna rats with large thymuses and WKY/NCrj rats with small thymuses suggested the presence of a major autosomal gene, Ten-1 , which contributes to thymus enlargement in a backcross population. Linkage studies between Ten-1 and microsatellite markers in backcross rats of (WKY/NCrj×BUF/Mna)Fl×BUF/Mna have led to the localization of Ten-1 in chromosome 1. This result may provide an approach to clone Tsr-1 , which could be allelic to Ten-1. 相似文献
33.
34.
Masato YASUI Hiroyuki TANAKA Toshiyuki ITO Yoshiki SEINO 《Nephrology (Carlton, Vic.)》1997,3(5):339-346
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor. 相似文献
35.
Prognostic significance of prostate specific antigen in endocrine treatment for prostatic cancer. 总被引:4,自引:0,他引:4
The prognostic value of prostate specific antigen was evaluated to predict disease progression after endocrine therapy in patients with prostatic cancer. A total of 73 patients was studied (6 with stage B2, 16 with stage C, 9 with stage D1 and 42 with stage D2 disease). Endocrine therapy included bilateral orchiectomy, diethylstilbestrol diphosphate and luteinizing hormone-releasing hormone analogue. Pre-treatment serum prostate specific antigen levels were determined in all patients with an enzyme immunoassay kit. During a followup of 4 to 68 months (average 24 months) clinical disease progression occurred in 24 of the 73 patients. The pre-treatment prostate specific antigen level by itself did not predict disease progression. Changes in prostate specific antigen level with treatment were correlated with the interval to disease progression in the 44 patients who had prostate specific antigen determinations at regular intervals after endocrine therapy and whose initial level was greater than 10 ng./ml. Patients who had a decrease in the prostate specific antigen levels of 80% or more within 1 month after the beginning of therapy survived significantly longer free of disease progression (p less than 0.001). Patients whose prostate specific antigen level remained elevated for more than 3 months had a high risk of disease progression within 2 years. Our study suggests that patients with the more favorable prognosis can be identified early, after 1 to 3 months of endocrine therapy, by the rapid decrease in the prostate specific antigen levels. 相似文献
36.
37.
Yoshitaka Hayashi Shigeaki Ohtake Yoshiki Sawa Hiroshi Imagawa Nobuaki Hirata Hikaru Matsuda 《General thoracic and cardiovascular surgery》1998,46(8):724-729
A 68-year-old man, who had underwent aortic valve replacement (AVR) with Björk-Shiley disc valve for aortic regurgitation 17 years ago, was transferred to our hospital complaining of facial ruddiness and swelling, without chest or back pain. Preoperative examination revealed DeBakey type II aortic dissection, which caused superior vena cava syndrome (SVC syndrome). Emergent ascending aortic replacement was performed, postoperatively central venous pressure (CVP) decreased from 33 to 9 mmHg, and SVC syndrome was relieved. Painless aortic dissection after AVR, presenting as SVC syndrome, is a rare case, and close follow-up should be performed under consideration of painless aortic dissection late after AVR. 相似文献
38.
39.
Boxall S Stanton T Hirai K Ward V Yasui T Tahara H Tamori A Nishiguchi S Shiomi S Ishiko O Inaba M Nishizawa Y Dawes R Bodmer W Beverley PC Tchilian EZ 《Human molecular genetics》2004,13(20):2377-2384
The CD45 antigen is a haemopoietic cell specific tyrosine phosphatase essential for antigen receptor mediated signalling in lymphocytes. Expression of different patterns of alternatively spliced CD45 isoforms is associated with distinct functions. We recently identified a polymorphism in exon 6 (A138G) of the gene encoding CD45 (PTPRC) that results in altered CD45 splicing. The 138G allele is present at a high frequency among Japanese (23.7%), with 5.1% individuals homozygous for the G allele. In this study we show that the A138G polymorphism is the cause of altered CD45 isoform expression, promoting splicing towards low molecular weight CD45 isoforms. We further report that the frequency of A138G heterozygotes is significantly reduced in number in cohorts of patients with autoimmune Graves' disease or hepatitis B infection, whereas G138G homozygotes are absent from a cohort of Hashimoto's thyroiditis patients. We also show that 138G individuals exhibit altered cytokine production in vitro and an increased proportion of memory T cells. These data suggest that the 138G variant allele strongly influences these diseases by modulation of immune mechanisms and may have achieved its high frequency as a result of a natural selection probably related to pathogen resistance. 相似文献