全文获取类型
收费全文 | 19007篇 |
免费 | 977篇 |
国内免费 | 29篇 |
专业分类
耳鼻咽喉 | 135篇 |
儿科学 | 382篇 |
妇产科学 | 451篇 |
基础医学 | 1690篇 |
口腔科学 | 602篇 |
临床医学 | 2073篇 |
内科学 | 3535篇 |
皮肤病学 | 159篇 |
神经病学 | 1697篇 |
特种医学 | 682篇 |
外科学 | 1818篇 |
综合类 | 171篇 |
一般理论 | 4篇 |
预防医学 | 4374篇 |
眼科学 | 228篇 |
药学 | 990篇 |
2篇 | |
中国医学 | 24篇 |
肿瘤学 | 996篇 |
出版年
2023年 | 1031篇 |
2022年 | 1590篇 |
2021年 | 1600篇 |
2020年 | 1633篇 |
2019年 | 895篇 |
2018年 | 685篇 |
2017年 | 888篇 |
2016年 | 944篇 |
2015年 | 824篇 |
2014年 | 1684篇 |
2013年 | 1146篇 |
2012年 | 737篇 |
2011年 | 628篇 |
2010年 | 903篇 |
2009年 | 908篇 |
2008年 | 471篇 |
2007年 | 468篇 |
2006年 | 422篇 |
2005年 | 328篇 |
2004年 | 274篇 |
2003年 | 241篇 |
2002年 | 249篇 |
2001年 | 219篇 |
2000年 | 174篇 |
1999年 | 161篇 |
1998年 | 128篇 |
1997年 | 106篇 |
1996年 | 118篇 |
1995年 | 23篇 |
1994年 | 23篇 |
1993年 | 24篇 |
1992年 | 56篇 |
1991年 | 56篇 |
1990年 | 51篇 |
1989年 | 52篇 |
1988年 | 43篇 |
1987年 | 20篇 |
1986年 | 15篇 |
1985年 | 17篇 |
1984年 | 22篇 |
1983年 | 7篇 |
1982年 | 14篇 |
1981年 | 10篇 |
1980年 | 9篇 |
1979年 | 11篇 |
1978年 | 7篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 11篇 |
1974年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system. 相似文献
3.
4.
In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol. 相似文献
5.
6.
7.
8.
《HPB : the official journal of the International Hepato Pancreato Biliary Association》2022,24(8):1201-1216
BackgroundPancreatic ductal adenocarcinoma (PDAC) has poor survival. Current treatments offer little likelihood of cure or long-term survival. This systematic review evaluates prognostic models predicting overall survival in patients diagnosed with PDAC.MethodsWe conducted a comprehensive search of eight electronic databases from their date of inception through to December 2019. Studies that published models predicting survival in patients with PDAC were identified.Results3297 studies were identified; 187 full-text articles were retrieved and 54 studies of 49 unique prognostic models were included. Of these, 28 (57.1%) were conducted in patients with advanced disease, 17 (34.7%) with resectable disease, and four (8.2%) in all patients. 34 (69.4%) models were validated, and 35 (71.4%) reported model discrimination, with only five models reporting values >0.70 in both derivation and validation cohorts. Many (n = 27) had a moderate to high risk of bias and most (n = 33) were developed using retrospective data. No variables were unanimously found to be predictive of survival when included in more than one study.ConclusionMost prognostic models were developed using retrospective data and performed poorly. Future research should validate instruments performing well locally in international cohorts and investigate other potential predictors of survival. 相似文献
9.
BackgroundRhythmic joint mobilizations (RJM) of the temporomandibular joint (TMJ) are employed to relieve pain and improve function in patients with temporomandibular disorders (TMD). However, the evidence on the immediate effects of RJM in patients with TMD is scarce. The aim of this study was to assess the immediate clinical and functional effects of RJM in patients with TMD.Materials and methodsThis was a one-group quasi-experimental before and after study. Thirty-eight patients with TMD were assessed by means of pain intensity (visual analogue score, VAS), pressure pain threshold (PPT, measured through pressure algometry on the masseter and temporal muscles), mouth opening (MO, measured with a ruler), and surface electromyographic activity of the masseter and temporal muscles (asymmetry index, AI). Measurements were performed before and after a single, 1-min session of RJM of each TMJ. All statistical analyses were performed using the SPSS version 20.0 statistical package.ResultsA statistical significant difference was found in pain intensity, PPT and MO after the intervention (p < 0.05). No difference was found in the AI. A large effect size was observed for pain intensity, PPT of the left and right masseter muscles and MO (d = 0.85–1.13), whereas for the left and right temporal muscles the effect size was moderate (d = 0.62) and small, respectively (d = 0.49).ConclusionIn this sample of patients with TMD, a single session of RJM of the TMJ seemed to be effective in reducing pain intensity, increasing PPT and improving MO immediately after the intervention, without differences in the AI. 相似文献
10.