全文获取类型
收费全文 | 34035篇 |
免费 | 2418篇 |
国内免费 | 577篇 |
专业分类
耳鼻咽喉 | 631篇 |
儿科学 | 544篇 |
妇产科学 | 483篇 |
基础医学 | 5627篇 |
口腔科学 | 463篇 |
临床医学 | 2791篇 |
内科学 | 7150篇 |
皮肤病学 | 1283篇 |
神经病学 | 2576篇 |
特种医学 | 2340篇 |
外科学 | 4383篇 |
综合类 | 160篇 |
一般理论 | 7篇 |
预防医学 | 1252篇 |
眼科学 | 1063篇 |
药学 | 2874篇 |
中国医学 | 441篇 |
肿瘤学 | 2962篇 |
出版年
2024年 | 15篇 |
2023年 | 239篇 |
2022年 | 815篇 |
2021年 | 1274篇 |
2020年 | 662篇 |
2019年 | 917篇 |
2018年 | 1112篇 |
2017年 | 897篇 |
2016年 | 1402篇 |
2015年 | 1934篇 |
2014年 | 2190篇 |
2013年 | 2435篇 |
2012年 | 3407篇 |
2011年 | 3251篇 |
2010年 | 2029篇 |
2009年 | 1680篇 |
2008年 | 2153篇 |
2007年 | 1943篇 |
2006年 | 1674篇 |
2005年 | 1563篇 |
2004年 | 1239篇 |
2003年 | 1066篇 |
2002年 | 914篇 |
2001年 | 344篇 |
2000年 | 335篇 |
1999年 | 246篇 |
1998年 | 173篇 |
1997年 | 128篇 |
1996年 | 87篇 |
1995年 | 66篇 |
1994年 | 48篇 |
1993年 | 53篇 |
1992年 | 68篇 |
1991年 | 80篇 |
1990年 | 46篇 |
1989年 | 64篇 |
1988年 | 62篇 |
1987年 | 55篇 |
1986年 | 39篇 |
1985年 | 30篇 |
1984年 | 22篇 |
1983年 | 29篇 |
1982年 | 16篇 |
1980年 | 18篇 |
1979年 | 31篇 |
1978年 | 25篇 |
1977年 | 32篇 |
1976年 | 20篇 |
1975年 | 16篇 |
1973年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Hae June Lee Yeonghoon Son Minyoung Lee Changjong Moon Sung Ho Kim In Sik Shin Miyoung Yang Sangwoo Bae Joong Sun Kim 《中国神经再生研究》2019,(9)
Sodium butyrate is a histone deacetylase inhibitor that affects various types of brain damages. To investigate the effects of sodium butyrate on hippocampal dysfunction that occurs after whole-brain irradiation in animal models and the effect of sodium butyrate on radiation exposure-induced cognitive impairments,adult C57BL/6 mice were intraperitoneally treated with 0.6 g/kg sodium butyrate before exposure to 10 Gy cranial irradiation. Cognitive impairment in adult C57BL/6 mice was evaluated via an object recognition test 30 days after irradiation. We also detected the expression levels of neurogenic cell markers(doublecortin)and phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor. Radiation-exposed mice had decreased cognitive function and hippocampal doublecortin and phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor expression. Sodium butyrate pretreatment reversed these changes. These findings suggest that sodium butyrate can improve radiation-induced cognitive dysfunction through inhibiting the decrease in hippocampal phosphorylated cAMP response element binding protein/brain-derived neurotrophic factor expression. The study procedures were approved by the Institutional Animal Care and Use Committee of Korea Institute of Radiological Medical Sciences(approval No. KIRAMS16-0002) on December 30, 2016. 相似文献
22.
23.
24.
25.
K.-C. Sung D.-C. Seo S.-J. Lee M.-Y. Lee S.H. Wild C.D. Byrne 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(5):489-495
Background and aims
It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.Methods and results
As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women.Conclusions
In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes. 相似文献26.
27.
Kyung Won Lee Mi Sook Cho Dayeon Shin 《International journal of food sciences and nutrition》2016,67(2):184-194
Urinary iodine concentrations (UICs) in the US have been reported to be stable since 1988–1994, although those in selected subgroups remained low. We aimed to investigate iodine status among adults (≥20 years) by two different criteria of assessing iodine deficiency in population. Utilizing National Health and Nutrition Examination Surveys 2001–2012, we conducted linear logistic regressions adjusting for covariates. The prevalence of <50?μg/L UIC was higher in women than in men; increased from 11.6% (2001–2004) to 13.2% (2009–2012) at the national level and in young adults, non-Hispanic blacks (NHBs) and non-users of iodine-containing supplements (all, p?<0.05); the adjusted odds ratios (95%CI) in young adults (1.54 [1.11–2.15], p =?0.0007) and NHBs (1.70 [1.15–2.52], p =?0.0078). Median UICs confirm women and NHBs being in borderline iodine status. Recognizing the critical consequence of iodine deficiency particularly in women and NHBs, regular monitoring of iodine status is important for public health in the US. 相似文献
28.
29.
H J Kim C H Kang Y T Kim S-W Sung J H Kim S M Lee C-G Yoo C-T Lee Y W Kim S K Han Y-S Shim J-J Yim 《The European respiratory journal》2006,28(3):576-580
Although surgical lung resection could improve prognosis in some patients with multidrug-resistant tuberculosis (MDR-TB), there are no reports on the optimal candidates for this surgery. The aim of the present study was to elucidate the prognostic factors for surgery in patients with MDR-TB. Patients who underwent lung resection for the treatment of MDR-TB between March 1993 and December 2004 were included in the present study. Treatment failure was defined as greater than or equal to two of the five cultures recorded in the final 12 months of treatment being positive, any one of the final three cultures being positive, or the patient having died during treatment. The variables that affected treatment outcomes were identified through univariate and multivariate logistic regression analysis. In total, 79 patients with MDR-TB were included in the present study. The treatment outcomes of 22 (27.8%) patients were classified as failure. A body mass index <18.5 kg x m(-2), primary resistance, resistance to ofloxacin and the presence of a cavitary lesion beyond the range of the surgical resection were associated with treatment failure. Low body mass index, primary resistance, resistance to ofloxacin and cavitary lesions beyond the range of resection are possible poor prognostic factors for surgical lung resection in multidrug-resistant tuberculosis patients. 相似文献
30.
Sung Woo Lee Sung Hyuk Choi Yunsik Hong Wanbae Kim 《European journal of emergency medicine》2006,13(2):117-118
Generally, a computed tomography scan is conducted for the diagnosis of stroke in the emergency department, because these scans are easier and faster in the detection of stroke. If there are no signs of hemorrhage on computed tomography scan, an ischemic stroke is diagnosed and treated accordingly. A magnetic resonance imaging scan may be taken in order to verify ischemic stroke. This process may lead to improper treatment and is time consuming. To address this situation, case studies are presented in which magnetic resonance imaging diffusion-weighted imaging and gradient recalled echo were performed to detect hemorrhagic and ischemic stroke and particularly, subarachnoid hemorrhage, which is undetectable with a computed tomography scan. 相似文献