收费全文 | 3594篇 |
免费 | 127篇 |
国内免费 | 12篇 |
耳鼻咽喉 | 23篇 |
儿科学 | 147篇 |
妇产科学 | 40篇 |
基础医学 | 509篇 |
口腔科学 | 37篇 |
临床医学 | 190篇 |
内科学 | 964篇 |
皮肤病学 | 43篇 |
神经病学 | 258篇 |
特种医学 | 103篇 |
外科学 | 588篇 |
综合类 | 12篇 |
预防医学 | 96篇 |
眼科学 | 36篇 |
药学 | 231篇 |
中国医学 | 9篇 |
肿瘤学 | 447篇 |
2023年 | 11篇 |
2022年 | 12篇 |
2021年 | 48篇 |
2020年 | 30篇 |
2019年 | 46篇 |
2018年 | 48篇 |
2017年 | 38篇 |
2016年 | 40篇 |
2015年 | 68篇 |
2014年 | 97篇 |
2013年 | 138篇 |
2012年 | 216篇 |
2011年 | 234篇 |
2010年 | 132篇 |
2009年 | 123篇 |
2008年 | 246篇 |
2007年 | 255篇 |
2006年 | 260篇 |
2005年 | 278篇 |
2004年 | 242篇 |
2003年 | 238篇 |
2002年 | 264篇 |
2001年 | 57篇 |
2000年 | 28篇 |
1999年 | 56篇 |
1998年 | 57篇 |
1997年 | 45篇 |
1996年 | 40篇 |
1995年 | 47篇 |
1994年 | 38篇 |
1993年 | 32篇 |
1992年 | 21篇 |
1991年 | 43篇 |
1990年 | 23篇 |
1989年 | 33篇 |
1988年 | 16篇 |
1987年 | 18篇 |
1986年 | 8篇 |
1985年 | 13篇 |
1984年 | 11篇 |
1983年 | 9篇 |
1982年 | 10篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1979年 | 8篇 |
1975年 | 5篇 |
1974年 | 4篇 |
1971年 | 3篇 |
1965年 | 4篇 |
1923年 | 3篇 |
Background
Although the clinicopathologic features and prognosis of Borrmann type advanced gastric cancer has been well characterized, those of advanced gastric cancer simulating early gastric cancer (AGC simulating EGC) still remains unclear.Methods
We reviewed 1985 gastric cancer patients who had undergone gastrectomy at our hospital to determine the clinicopathologic characteristics, susceptible sites for lymph node metastasis, and prognosis of AGC simulating EGC in comparison with Borrmann type advanced gastric cancer.Results
Among 102 patients with AGC simulating EGC, 100 patients (98%) had tumors with depressed type appearance. The frequencies of serosal invasion, lymph node metastasis, lymphatic vessel invasion, blood vessel invasion, and liver metastasis were significantly lower in AGC simulating EGC than in Borrmann type tumors. The prognosis of AGC simulating EGC was significantly better than that of the Borrmann type tumors. Multivariate analysis indicated that the gross appearance was an independent prognostic factor. In patients with AGC simulating EGC which invaded to the the muscularis propria (MP), most lymph node metastasis was restricted with the perigastric lymph nodes (1st-titer lymph nodes) and lymph node metastasis to 2nd-titer lymph nodes was only observed at station 8a.Conclusion
AGC simulating EGC is less advanced in comparison with Borrmann type advanced gastric cancer. Based on the results of susceptible sites for lymph node metastasis in the current study, limited lymph node dissection could be indicated for AGC simulating EGC whose depth of invasion is MP. 相似文献To investigate the clinical characteristics of patients with ischemic stroke following the 2016 Kumamoto earthquake.
MethodsWe retrospectively studied patients with ischemic stroke admitted to 5 stroke centers for 1 year after the earthquake. We compared clinical characteristics in these patients (the post-earthquake group) to those in the patients with ischemic stroke admitted during the same period from the previous 3 years (the pre-earthquake group). Additionally, we analyzed the trend of the incidence rate of stroke before and after the earthquake.
ResultsA total of 1979 patients were admitted after the earthquake; 5670 (1,890/year on average) patients were admitted before the earthquake. A first-ever ischemic stroke (71 vs. 75%) and premorbid modified Rankin Scale > 1 (26 vs. 29%) were found significantly more frequently in patients after the earthquake. National Institutes of Health Stroke Scale score ≤ 2 at discharge (60 vs. 65%) was found more frequently in patients after the earthquake, although non-discharge to home (65 vs. 70%) was more frequent in patients after the earthquake. Trend analysis revealed a decrease of small vessel occlusion and large artery atherosclerosis in the month after the earthquake.
ConclusionsThe 2016 Kumamoto earthquake may have affected the characteristics of stroke during the early phase of the earthquake and increased the difficulty in returning home.
相似文献Background
Modifying the surface and substrate of a crosslinked polyethylene (CLPE) liner may be beneficial for high wear resistance as well as high oxidative stability and excellent mechanical properties, which would be useful in contributing to the long-term performance of orthopaedic bearings. A grafted poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) layer on a vitamin E-blended crosslinked PE (HD-CLPE[VE]) surface may provide hydrophilicity and lubricity without compromising the oxidative stability or mechanical properties.Questions/purposes
(1) Will the modifications (PMPC grafting and vitamin E blending) affect the lubrication characteristics of the CLPE surface? (2) Will the modifications affect wear resistance? (3) Will the modifications affect fatigue resistance?Methods
We investigated the effects of surface and substrate modifications (PMPC grafting and vitamin E blending) on the wear and fatigue fracture of thin CLPE samples. For each of the untreated and PMPC-grafted CLPE surfaces with and without vitamin E blended (four groups), wettability and lubricity surface analyses were conducted as well as multidirectional wear and impact-to-wear tests using a pin-on-disk testing machine.Results
The water wettability and lubricity (CLPE [mean ± 95% confidence interval]: 23.2° ± 1.8°, 0.005 ± 0.001; HD-CLPE[VE]: 26.0° ± 2.3°, 0.009 ± 0.003) of the PMPC-grafted surfaces were greater (p < 0.001) than that (CLPE: 90.3° ± 1.2°, 0.067 ± 0.015; HD-CLPE[VE]: 90.8° ± 2.0°, 0.063 ± 0.008) of the untreated surface regardless of vitamin E additives. It was observed that the PMPC grafting (CLPE: 0.23 ± 0.06 mg; HD-CLPE[VE]: 0.05 ± 0.10 mg) was associated with reduced gravimetric wear (CLPE: 0.53 ± 0.08 mg, p = 0.004 HD-CLPE[VE]: 0.23 ± 0.07 mg, p = 0.038) in the multidirectional wear test. The PMPC-grafted surface characteristics did not appear to affect the impact fatigue resistance regardless of vitamin E blending.Conclusions
PMPC grafting improved the surface hydrophilicity and lubricity, and it reduced the gravimetric wear in terms of multidirectional sliding. It did not result in differences in terms of the impact-to-unidirectional sliding regardless of vitamin E blending. Further research is needed to evaluate the wear resistance of PMPC-grafted HD-CLPE(VE) in long-term hip simulator tests under normal and severe conditions, which may offer useful clues to the possible performance of these materials in vivo.Clinical Relevance
Our preliminary in vitro findings suggest that some improvement in the wear performance of crosslinked polyethylene acetabular liners in total hip arthroplasty could be obtained using PMPC grafting. Further research is needed to evaluate the wear resistance of PMPC-grafted HD-CLPE(VE) in long-term hip simulator tests under normal and severe conditions, which may offer useful clues to the possible performance of these materials in vivo. 相似文献![点击此处可从《International journal of urology》网站下载免费的PDF全文](/ch/ext_images/free.gif)