全文获取类型
收费全文 | 1202篇 |
免费 | 100篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 40篇 |
儿科学 | 31篇 |
妇产科学 | 42篇 |
基础医学 | 169篇 |
口腔科学 | 24篇 |
临床医学 | 68篇 |
内科学 | 261篇 |
皮肤病学 | 38篇 |
神经病学 | 120篇 |
特种医学 | 18篇 |
外科学 | 179篇 |
综合类 | 9篇 |
预防医学 | 33篇 |
眼科学 | 10篇 |
药学 | 63篇 |
肿瘤学 | 201篇 |
出版年
2023年 | 3篇 |
2022年 | 12篇 |
2021年 | 14篇 |
2020年 | 21篇 |
2019年 | 27篇 |
2018年 | 21篇 |
2017年 | 14篇 |
2016年 | 43篇 |
2015年 | 19篇 |
2014年 | 46篇 |
2013年 | 58篇 |
2012年 | 74篇 |
2011年 | 66篇 |
2010年 | 43篇 |
2009年 | 46篇 |
2008年 | 60篇 |
2007年 | 82篇 |
2006年 | 66篇 |
2005年 | 86篇 |
2004年 | 67篇 |
2003年 | 63篇 |
2002年 | 78篇 |
2001年 | 19篇 |
2000年 | 13篇 |
1999年 | 22篇 |
1998年 | 26篇 |
1997年 | 22篇 |
1996年 | 16篇 |
1995年 | 12篇 |
1994年 | 13篇 |
1993年 | 11篇 |
1992年 | 14篇 |
1991年 | 13篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 12篇 |
1987年 | 8篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1984年 | 14篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 8篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1964年 | 2篇 |
排序方式: 共有1306条查询结果,搜索用时 15 毫秒
61.
Yue Cao Ph.D. Aron Popovtzer M.D. Diana Li B.S.E. Douglas B. Chepeha M.D. Jeffrey S. Moyer M.D. Mark E. Prince M.D. Francis Worden M.D. Theodoros Teknos M.D. Carol Bradford M.D. Suresh K. Mukherji M.D. Avraham Eisbruch M.D. 《International journal of radiation oncology, biology, physics》2008,72(5):1287-1290
62.
Summary Forty children and 53 adults with a total of 111 atelectatic ears were operated on and followed up. Eight-four ears underwent tympanoplasty, while 27 ears underwent both a tympanoplasty and a mastoid operation. There were no statistically significant differences between the two operation groups as far as their age groups and the extent of the disease present. After follow-up of over 4 years, aeration of the middle ear was found to be better in the tympanoplasty group alone when compared with ears with also had mastoid operations. 相似文献
63.
Inositol, a precursor of the PIP cycle that was reported to have therapeutic effects in depressive patients and to be effective in two animal models of depression, was evaluated in the forced swim test using the genetic Flinders Sensitive Line (FSL) rats model of depression. Groups of rats were tested in a 2 x 2 design with Strain (FSL or Control) as one factor and Drug (Inositol or Placebo) as the second factor. Rats received chronic treatment (daily for 14 days) with inositol (1.2 g/kg) or placebo (1:2 glucose/mannitol solution). On day 14 rats were exposed to the forced swim test for 5 min and their behavior videotaped. Tapes were analyzed for three levels of activity: immobility, swimming, and vigorous struggle. Inositol countered the exaggerated immobility of FSL rats in the forced swim test, without affecting control animals. Data support our previous suggestion of inositol as a potential antidepressant. 相似文献
64.
Carbamylphosphate synthase is the first enzymatic reaction of the urea cycle. Its activator, N-acetylglutamate, is synthesized from acetyl-CoA and glutamate in a reaction catalyzed by N-acetylglutamate synthase (NAGS). We have identified the putative human NAGS gene and report the first mutation in this gene in a family with carbamylglutamate responsive hyperammonemia and normal activity of the urea cycle enzymes. Mutation analysis has a higher diagnostic specificity than the enzymatic assay in NAGS deficiency. A therapeutic trial with carbamylglutamate is recommended whenever hyperammonemia without an organic aciduria, increased orotate excretion, or diagnostic amino acidemia/uria is detected. 相似文献
65.
66.
67.
68.
69.
Coen Rasch Avraham Eisbruch Peter Remeijer Luc Bos Mischa Hoogeman Marcel van Herk Joos V Lebesque 《International journal of radiation oncology, biology, physics》2002,52(1):120-127
PURPOSE: To determine the influence of observer variation and treatment planner variation on the dose delivered to the target and normal structures when irradiating paranasal sinus carcinomas. PATIENTS AND METHODS: Nine patients with paranasal sinus tumors underwent debulking surgery and subsequent radiation therapy. Two observers from two different institutions delineated the clinical target volumes (CTVs) for the elective and the boost volumes. These volumes were expanded in three dimensions with a 5-mm margin. At both institutions, a three-dimensional conformal treatment plan of 46 Gy to the elective volumes, plus 20 Gy to the boost target volumes, was designed. The delineated volumes and treatment plans were compared. RESULTS: The mean volume ratio between institutions of the elective CTVs was 0.9 (standard error = 0.05). The differences were located mainly at the bottom of the nasal cavity and at the frontal border of the target areas. The differences in boost CTVs were large; the mean volume ratio was 2.6 (standard error = 0.58). After expansion of the CTV, the mean distance between the planning target volume (PTV) and the chiasm differed by 0.5 cm between the two institutions. Cases with smaller distances between the PTV and the chiasm had more underdosage to the PTV. This effect was less pronounced for institution A (1 vol.%/cm) than for institution B (10 vol.%/cm) treatment plans, which were less conformal. When the treatment plan was designed for the PTV of institution B, 23 volume % of the PTV of institution A received <95% of the prescribed dose. If the treatment plan was designed for the (on average larger) PTV of institution A, the underdosed volume of PTV at institution B was 17%. The relative underdosage to the "other" PTV was larger when the original treatment plan was more conformal. CONCLUSION: In the irradiation of paranasal sinus cancer, both the treatment planner and the observer have a significant influence on the dose to the target and organs at risk. Both effects are similar in magnitude. The observer effect increases with more conformal treatment plans. Minimizing the observer variation is important for adequate irradiation of paranasal sinus cancer. 相似文献
70.
Inhibition of human cancer cell growth and metastasis in nude mice by oral intake of modified citrus pectin 总被引:26,自引:0,他引:26
Nangia-Makker P Hogan V Honjo Y Baccarini S Tait L Bresalier R Raz A 《Journal of the National Cancer Institute》2002,94(24):1854-1862
BACKGROUND: The role of dietary components in cancer progression and metastasis is an emerging field of clinical importance. Many stages of cancer progression involve carbohydrate-mediated recognition processes. We therefore studied the effects of high pH- and temperature-modified citrus pectin (MCP), a nondigestible, water-soluble polysaccharide fiber derived from citrus fruit that specifically inhibits the carbohydrate-binding protein galectin-3, on tumor growth and metastasis in vivo and on galectin-3-mediated functions in vitro. METHODS: In vivo tumor growth, angiogenesis, and metastasis were studied in athymic mice that had been fed with MCP in their drinking water and then injected orthotopically with human breast carcinoma cells (MDA-MB-435) into the mammary fat pad region or with human colon carcinoma cells (LSLiM6) into the cecum. Galectin-3-mediated functions during tumor angiogenesis in vitro were studied by assessing the effect of MCP on capillary tube formation by human umbilical vein endothelial cells (HUVECs) in Matrigel. The effects of MCP on galectin-3-induced HUVEC chemotaxis and on HUVEC binding to MDA-MB-435 cells in vitro were studied using Boyden chamber and labeling assays, respectively. The data were analyzed by two-sided Student's t test or Fisher's protected least-significant-difference test. RESULTS: Tumor growth, angiogenesis, and spontaneous metastasis in vivo were statistically significantly reduced in mice fed MCP. In vitro, MCP inhibited HUVEC morphogenesis (capillary tube formation) in a dose-dependent manner. In vitro, MCP inhibited the binding of galectin-3 to HUVECs: At concentrations of 0.1% and 0.25%, MCP inhibited the binding of galectin-3 (10 micro g/mL) to HUVECs by 72.1% (P =.038) and 95.8% (P =.025), respectively, and at a concentration of 0.25% it inhibited the binding of galectin-3 (1 micro g/mL) to HUVECs by 100% (P =.032). MCP blocked chemotaxis of HUVECs toward galectin-3 in a dose-dependent manner, reducing it by 68% at 0.005% (P<.001) and inhibiting it completely at 0.1% (P<.001). Finally, MCP also inhibited adhesion of MDA-MB-435 cells, which express galectin-3, to HUVECs in a dose-dependent manner. CONCLUSIONS: MCP, given orally, inhibits carbohydrate-mediated tumor growth, angiogenesis, and metastasis in vivo, presumably via its effects on galectin-3 function. These data stress the importance of dietary carbohydrate compounds as agents for the prevention and/or treatment of cancer. 相似文献