全文获取类型
收费全文 | 4135篇 |
免费 | 612篇 |
国内免费 | 63篇 |
出版年
2024年 | 9篇 |
2023年 | 123篇 |
2022年 | 110篇 |
2021年 | 183篇 |
2020年 | 157篇 |
2019年 | 204篇 |
2018年 | 164篇 |
2017年 | 157篇 |
2016年 | 190篇 |
2015年 | 191篇 |
2014年 | 265篇 |
2013年 | 387篇 |
2012年 | 174篇 |
2011年 | 183篇 |
2010年 | 129篇 |
2009年 | 149篇 |
2008年 | 141篇 |
2007年 | 182篇 |
2006年 | 153篇 |
2005年 | 115篇 |
2004年 | 135篇 |
2003年 | 124篇 |
2002年 | 120篇 |
2001年 | 82篇 |
2000年 | 69篇 |
1999年 | 70篇 |
1998年 | 65篇 |
1997年 | 71篇 |
1996年 | 74篇 |
1995年 | 47篇 |
1994年 | 40篇 |
1993年 | 52篇 |
1992年 | 63篇 |
1991年 | 47篇 |
1990年 | 50篇 |
1989年 | 42篇 |
1988年 | 33篇 |
1987年 | 30篇 |
1986年 | 24篇 |
1985年 | 36篇 |
1984年 | 26篇 |
1983年 | 29篇 |
1982年 | 38篇 |
1981年 | 25篇 |
1980年 | 13篇 |
1979年 | 10篇 |
1977年 | 11篇 |
1976年 | 3篇 |
1972年 | 3篇 |
1971年 | 3篇 |
排序方式: 共有4810条查询结果,搜索用时 15 毫秒
61.
Background
Diabetes is a growing worldwide problem that is strongly associated with atherosclerosis. Screening and intervention for diabetes in the earliest stages are advocated for the prevention of diabetic complications and cardiovascular disease.Scope of review
This review gives a background of and discusses the potential clinical utility of glycated albumin (GA) in diabetes.Major conclusions
GA is a ketoamine formed via a non-enzymatic glycation reaction of serum albumin and it reflects mean glycemia over two to three weeks. GA can be used for patients with anemia or hemoglobinopathies for whom the clinically measured hemoglobin A1c level may be inaccurate. Because both serum and plasma samples can be used, GA can be analyzed from the same samples as common biological markers. GA is a useful marker for the screening of diabetes in a medical evaluation. It can be also used to determine the effectiveness of treatment before initiating or changing medications for diabetic patients. GA is potentially an atherogenic protein in the development of diabetic atherosclerosis.General significance
GA measurement is useful as part of a routine examination to screen for both diabetes and atherosclerosis. This article is part of a Special Issue entitled Serum Albumin. 相似文献62.
Huadan Ye Xiaojing Li Lingyan Wang Qi Liao Leiting Xu Yi Huang Liming Xu Xuting Xu Cheng Chen Hangyu Wu Yanping Le Qiong Liu Meng Ye Changzheng Dong Shiwei Duan 《Gene》2013
Aims
The aim of this study was to evaluate the combined contribution of 12 genetic variants to the risk of coronary heart disease (CHD).Methods
Through a comprehensive literature search for genetic variants involved in the CHD association study, we harvested a total of 10 genes (12 variants) for the current meta-analyses. These genes consisted of GPX1 (rs1050450), PPARD (rs2016520), ALOX15 (rs34210653), SELPLG (rs2228315), FCGR2A (rs1801274), CCL5 (rs2107538), CYP1A1 (rs4646903), TP53 (rs1042522), CX37 (rs1764391), and PECAM1 (rs668, rs12953, and rs1131012).Results
A total of 45 studies among 23,314 cases and 28,430 controls were retrieved for the meta-analyses of 12 genetic variants. The results showed a significant association between the GPX1 rs1050450 polymorphism and CHD (odd ratio (OR) = 1.61, 95% confidence interval (CI) = 1.25–2.07, P = 0.0002). Other meta-analyses of the rest 11 variants suggested a lack of association with the risk of CHD.Conclusion
Our results confirmed that GPX1 rs1050450 was associated with susceptibility to CHD in Chinese and Indian populations. 相似文献63.
64.
65.
Ying Ma Shun-Xian Wang Yun Liu Guo-Guang Peng Xiao-Ming Wang Bo Zhang Bi-Hua Wu Ju-Ming Yu 《Gene》2013
Objectives
Ischemic stroke is influenced by both environmental and genetic factors. The CD40/CD40L system is related to proinflammatory and prothrombogenic responses, which are involved in the pathophysiology of ischemic stroke. The aim of this study was to evaluate association between the CD40 -1C/T single nucleotide polymorphism (SNP) and ischemic stroke in a Chinese population.Methods
We conducted a case–control study including 286 ischemic stroke patients and 336 controls. CD40 -1C/T SNP was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing methods, and evaluated its relevance to ischemic stroke susceptibility.Results
Significantly increased ischemic stroke risk was found to be associated with the T allele of CD40 -1C/T (OR = 1.273, 95% CI = 1.016–1.594). The frequencies of CT and TT/CT genotypes of CD40 -1C/T in ischemic stroke patients were significantly higher than those of controls, respectively (for CT: OR = 2.350, 95% CI = 1.601–3.449; for TT/CT: OR = 2.148, 95% CI = 1.479–3.119). And, similar results were obtained after adjusting non-matched variables. We found that the frequency of carried T genotypes (TT and TT/CT) was significantly increased in patients with history of stroke compared with patients without (for TT: OR = 6.538, 95%CI = 1.655–25.833; for TT/CT: OR = 3.469, 95%CI = 1.031–11.670), respectively.Conclusions
The findings suggested that the CD40 -1C/T polymorphism might contribute to the susceptibility to ischemic stroke in the Chinese population, and might be associated with history of previous stroke. 相似文献66.
Yosuke Suzuki Hiroki Itoh Fuminori Sato Kanako Kawasaki Yukie Sato Takashi Fujioka Yuhki Sato Keiko Ohno Hiromitsu Mimata Satoshi Kishino 《Journal of lipid research》2013,54(9):2568-2572
Several previous studies have shown that renal failure decreases not only renal elimination but also metabolic clearance of drugs, particularly those metabolized by CYP3A. However, whether recovery of renal function results in recovery of hepatic CYP3A activity remains unknown. In this study, we evaluated the effect of renal function on CYP3A activity after kidney transplantation in patients with end-stage renal disease (ESRD) by measuring the change in CYP3A activity using plasma concentration of 4β-hydroxycholesterol as a biomarker. The study enrolled 13 patients with ESRD who underwent the first kidney allograft transplantation. Morning blood samples were collected before and 3, 7, 10, 14, 21, 30, 60, 90, 120, 150 and 180 days after kidney transplantation. Plasma concentration of 4β-hydroxycholesterol was measured using GC-MS. Compared with before kidney transplantation, creatinine clearance increased significantly from day 3 after kidney transplantation and stabilized thereafter. Plasma concentration of 4β-hydroxycholesterol was elevated significantly on days 90 and 180 after kidney transplantation. In conclusion, this study suggests the recovery of CYP3A activity with improvement in renal function after kidney transplantation in patients with ESRD. 相似文献
67.
Gary M. Kupfer 《The Yale journal of biology and medicine》2013,86(4):491-497
Fanconi anemia (FA) is a fascinating, rare genetic disorder marked by congenital
defects, bone marrow failure, and cancer susceptibility. Research in recent
years has led to the elucidation of FA as a DNA repair disorder and involved
multiple pathways as well as having wide applicability to common cancers,
including breast, ovarian, and head and neck. This review will describe the
clinical aspects of FA as well as the current state of its molecular
pathophysiology. In particular, work from the Kupfer laboratory will be
described that demonstrates how the FA pathway interacts with multiple DNA
repair pathways, including the mismatch repair system and signal transduction
pathway of the DNA damage response. 相似文献
68.
José Rodrigues Coura Pedro Albajar Vi?as Lucia Maria Brum-Soares Andréa Silvestre de Sousa Sérgio Salles Xavier 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1009-1013
A case-control study on the morbidity of Chagas heart disease was carried out in the
municipality of Barcelos in the microregion of the Rio Negro, state of Amazonas. One
hundred and six individuals, who were serologically positive for Trypanosoma
cruzi infection, as confirmed by at least two techniques with different
principles, were matched according to age and sex with an equal number of
seronegative individuals. The cases and controls were evaluated using an
epidemiological questionnaire and clinical, electrocardiograph and echocardiograph
examinations. In the seroepidemiological evaluation, 62% of the interviewees
recognised triatomines and most of them confirmed that they had seen these insects in
the piassava plantations of the riverside communities of the Negro River tributaries.
Of the seropositive patients, 25.8% affirmed that they had been stung by the
triatomines and 11.7% denied having been stung. The principal clinical manifestations
of the seropositive individuals were palpitations, chest pain and dyspnoea upon
effort. Cardiac auscultation revealed extrasystoles, bradycardia and systolic
murmurs. The electrocardiographic alterations were ventricular extrasystoles, left
and right bundle branch block, atrioventricular block and primary T wave alterations.
The echocardiogram was altered in 22.6% of the seropositive individuals and in 8.5%
of the seronegative individuals. 相似文献
69.
Jose Ramon Garmendia Leiza Jesus Maria Andres de Llano Juan Bautista Lopez Messa Carlos Alberola Lopez ARIAM Study Group 《Chronobiology international》2013,30(1):129-141
The aim of this study was to determine the existence of the circadian rhythm (CR) in the onset of acute myocardial infarction (AMI) in different patient subgroups. Information was collected about 41,244 infarctions from the database of the ARIAM (Analysis of Delay in AMI) Spanish multicenter study. CR in AMI were explored in subgroups of cases categorized by age, gender, previous ischemic heart disease (PIHD), outcome in coronary care unit, infarction electrocardiograph (ECG) characteristics (Q wave or non‐Q wave), and location of AMI. Cases were classified according to these variables in the different subgroups. To verify the presence of CR, a simple test of equality of time series based on the multiple‐sinusoid (24, 12, and 8 h periods) cosinor analysis was developed. For the groups as a whole, the time of pain onset as an indicator of the AMI occurrence showed a CR (p<0.0001), with a morning peak at 10:10 h. All the analyzed subgroups also showed CR. Comparison between subgroups showed significant differences in the PIHD (p<0.01) and infarction ECG characteristics (p<0.01) groups. The CR of the subgroup with Q‐wave infarction differed from that of non‐Q wave subgroup (p<0.01) when the patients had PIHD (23% in Q wave infarction vs. 39.2% in non‐Q wave). AMI onset followed a CR pattern, which is also observed in all analyzed subgroups. Differences in the CR according to the Q/non‐Q wave infarction characteristics could be determined by PIHD. The cosinor model fit with three components (24, 12, and 8 h periods) showed a higher sensitivity than the single 24 h period analysis. 相似文献
70.
《Chronobiology international》2013,30(5):399-408
The purpose of this study was to assess the ischemic burden and the hemodynamic changes during daily activities in patients with coronary heart disease. Three exercise tests were performed during the day (10:00 a.m., 2:00 p.m., 6:00 p.m.), recording ST-segment depression, pulmonary artery pressure, pulmonary wedge pressure, and cardiac output as well as heart rate and systemic blood pressure during placebo and nitrate therapy. With placebo as well as nitrate therapy there was a gradual increase of ischemia and preload and a decrease of cardiac output during the day. High nitrate concentrations led to a significant reduction of both preload and ST depression with a marked circadian phase dependency of cardiovascular effects. 相似文献