全文获取类型
收费全文 | 33084篇 |
免费 | 3222篇 |
国内免费 | 562篇 |
专业分类
耳鼻咽喉 | 155篇 |
儿科学 | 1141篇 |
妇产科学 | 603篇 |
基础医学 | 2697篇 |
口腔科学 | 333篇 |
临床医学 | 3767篇 |
内科学 | 9015篇 |
皮肤病学 | 445篇 |
神经病学 | 2149篇 |
特种医学 | 553篇 |
外科学 | 3167篇 |
综合类 | 2424篇 |
现状与发展 | 1篇 |
一般理论 | 12篇 |
预防医学 | 6080篇 |
眼科学 | 815篇 |
药学 | 1602篇 |
3篇 | |
中国医学 | 352篇 |
肿瘤学 | 1554篇 |
出版年
2024年 | 146篇 |
2023年 | 580篇 |
2022年 | 352篇 |
2021年 | 621篇 |
2020年 | 551篇 |
2019年 | 300篇 |
2018年 | 867篇 |
2017年 | 875篇 |
2016年 | 941篇 |
2015年 | 925篇 |
2014年 | 875篇 |
2013年 | 1205篇 |
2012年 | 1993篇 |
2011年 | 2995篇 |
2010年 | 1567篇 |
2009年 | 1283篇 |
2008年 | 2046篇 |
2007年 | 1999篇 |
2006年 | 1811篇 |
2005年 | 1944篇 |
2004年 | 2836篇 |
2003年 | 2523篇 |
2002年 | 1816篇 |
2001年 | 1301篇 |
2000年 | 645篇 |
1999年 | 599篇 |
1998年 | 516篇 |
1997年 | 474篇 |
1996年 | 230篇 |
1995年 | 193篇 |
1994年 | 171篇 |
1993年 | 192篇 |
1992年 | 186篇 |
1991年 | 133篇 |
1990年 | 131篇 |
1989年 | 109篇 |
1988年 | 98篇 |
1987年 | 85篇 |
1986年 | 71篇 |
1985年 | 62篇 |
1984年 | 45篇 |
1983年 | 30篇 |
1982年 | 33篇 |
1981年 | 30篇 |
1980年 | 23篇 |
1979年 | 39篇 |
1978年 | 22篇 |
1975年 | 20篇 |
1974年 | 27篇 |
1968年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
81.
贵阳地区1?055例骨密度检测分析 总被引:13,自引:0,他引:13
采用日本阿洛卡公司双能量骨密测量仪,选择受检者桡骨远端1/3处为测量点,对贵阳地区1055例人群成人桡骨的骨密度进行测量,取得不同性别各年龄段的骨密度值,同时计算出贵阳地区成人桡骨各年龄段的骨密度均值及标准偏差。 相似文献
82.
France 《International digest of health legislation》1994,45(4):473-482
83.
France 《International digest of health legislation》1994,45(4):495-496
84.
France 《International digest of health legislation》1995,46(4):495-496
85.
Maïthe Tauber Catherine Pienkowski Pierre Rochiccioli 《European journal of pediatrics》1994,153(5):311-316
Sixty-five patients (22 boys and 43 girls) presenting with familial tall stature were investigated with regard to growth hormone (GH) secretion, both physiological and after stimulation with thyrotropin releasing hormone (TRH) and growth hormone relasing hormone (GHRH). Plasma insulin-like growth factor-I (IGF-I) was also measured. Two groups of patients were distinguished according to their physiological secretion of GH: a high secretory group (n=49) with a mean 24 h integrated concentration of GH (IC-GH) of 5.4±2.3 g/l per minute and a large number of peaks (5.1±1.6 in 24 h), and a low secretory group (n=16) with a mean 24 h IC-GH of 2.1±0.5 g/l per minute and few peaks (3.3±1.3 in 24h). Plasma IGF-I levels and GH peak values after the TRH test were significantly higher in the high secretory group. These results indicate that familial tall stature is the consequence either of hypersecretion of GH or of hypersensivity to this hormone (IGF-I levels being normal in spite of low GH levels). 相似文献
86.
Without appropriate commitment dedication from all sectors of government the significance of health objectives set forth in Healthy People will continue to be diluted more importantly the health of this nation will not improve.Ann Coulston MS RD FADA as part of ADA'S official comments to the US 《Journal of the American Dietetic Association》1999,99(4):420
87.
The measurement of fractional synthesis rate is based on the following assumptions: amino acids for protein synthesis are supplied by an intracellular pool; amino acids from protein degradation are not recycled preferentially to protein synthesis; and proteins turn over at a homogeneous rate. To test these assumptions, a mechanistic, theoretical model of protein turnover for a nongrowing 26-g mouse was developed on the basis of data from the literature. The model consisted of three protein pools turning over at fast (102 micromol Leu, t1/2= 11.5 h), medium (212 micromol Leu, t1/2 = 16.6 h) or slow (536 micromol Leu, t1/2 = 71.5 h) rates and extracellular (1.69 micromol Leu), leucyl-tRNA (0.0226 micromol Leu) and intracellular (5.72 micromol Leu) amino acid pools that exchanged amino acids. The flow of amino acids from the protein pools to the leucyl-tRNA pool determined the amount of recycling. The flow of amino acids from the extracellular pool to aminoacyl tRNA determined the amount of channeling. Two flooding dose data sets were used to evaluate specific radioactivity changes predicted by the model. Predictions of specific radioactivities using flooding dose, pulse dose or continuous infusion methods indicated that the model can be a useful tool in estimating the rates of channeling and recycling. However, it was found that use of data from flooding dose experiments might cause inaccurate predictions of certain fluxes. 相似文献
88.
Centers for Disease Control Prevention 《MMWR. Morbidity and mortality weekly report》1999,48(8):159-162
Immune globulin intravenous (IGIV) is a lifesaving treatment for patients with primary immunodeficiency. Since November 1997, a shortage of IGIV has existed in the United States. In 1998, the Food and Drug Administration (FDA) required pharmaceutical companies to increase the frequency of reporting on IGIV distribution from biannually to monthly; in addition, FDA facilitated IGIV distribution and informed clinicians about the ongoing shortage. To assess the impact of the IGIV shortage on patient care, in 1998 the Immune Deficiency Foundation (IDF) surveyed physicians caring for immunodeficient patients about whether they have had difficulty obtaining IGIV, measures they have taken because of the shortage, and the effect of the shortage on their patients. This report summarizes data reported to FDA and data obtained from the IDF survey and provides recommendations for IGIV use during the shortage. 相似文献
89.
Centers for Disease Control Prevention 《MMWR. Morbidity and mortality weekly report》1999,48(7):140-143
In November 1996, residents of Oregon approved a ballot measure increasing the cigarette tax by 30 cents (to 68 cents per pack). The measure stipulated that 10% of the additional tax revenue be allocated to the Oregon Health Division (OHD) to develop and implement a tobacco-use prevention program. In 1997, OHD created Oregon's Tobacco Prevention and Education Program (TPEP), a comprehensive, community-based program modeled on the successful tobacco-use prevention programs in California and Massachusetts. To assess the effects of the tax increase and TPEP in Oregon, OHD evaluated data on the number of packs of cigarettes taxed before (1993-1996) and after (1997-1998) the ballot initiative and implementation of the program. Oregon's results also were compared with national data. This report summarizes the results of the analysis, which indicate that consumption of cigarettes in Oregon declined substantially after implementation of the excise tax and TPEP and exceeded the national rate of decline. 相似文献
90.
Centers for Disease Control Prevention 《MMWR. Morbidity and mortality weekly report》1999,48(38):859-860
The United Nations (UN) estimates that the world's population will reach six billion on October 12, 1999. The world's population reached one billion in 1804; subsequently, one billion increases came at intervals of 123, 33, 14, 13, and 12 years. Population growth rates increased over time because of high fertility rates and declines in mortality rates, especially since the early to mid-1900s. The UN projects that it will take 14 years for the world's population to reach 7 billion and another 15 years to reach 8 billion. 相似文献