全文获取类型
收费全文 | 33201篇 |
免费 | 2014篇 |
国内免费 | 379篇 |
专业分类
耳鼻咽喉 | 541篇 |
儿科学 | 356篇 |
妇产科学 | 464篇 |
基础医学 | 5526篇 |
口腔科学 | 876篇 |
临床医学 | 2702篇 |
内科学 | 6259篇 |
皮肤病学 | 1315篇 |
神经病学 | 2424篇 |
特种医学 | 2234篇 |
外国民族医学 | 1篇 |
外科学 | 4134篇 |
综合类 | 172篇 |
一般理论 | 5篇 |
预防医学 | 1556篇 |
眼科学 | 579篇 |
药学 | 3341篇 |
中国医学 | 445篇 |
肿瘤学 | 2664篇 |
出版年
2023年 | 171篇 |
2022年 | 576篇 |
2021年 | 1237篇 |
2020年 | 560篇 |
2019年 | 801篇 |
2018年 | 976篇 |
2017年 | 799篇 |
2016年 | 1154篇 |
2015年 | 1533篇 |
2014年 | 1805篇 |
2013年 | 2068篇 |
2012年 | 3079篇 |
2011年 | 3018篇 |
2010年 | 1730篇 |
2009年 | 1518篇 |
2008年 | 2093篇 |
2007年 | 1927篇 |
2006年 | 1690篇 |
2005年 | 1565篇 |
2004年 | 1203篇 |
2003年 | 1057篇 |
2002年 | 898篇 |
2001年 | 788篇 |
2000年 | 724篇 |
1999年 | 514篇 |
1998年 | 209篇 |
1997年 | 135篇 |
1996年 | 118篇 |
1995年 | 81篇 |
1994年 | 98篇 |
1993年 | 81篇 |
1992年 | 148篇 |
1991年 | 155篇 |
1990年 | 171篇 |
1989年 | 137篇 |
1988年 | 122篇 |
1987年 | 110篇 |
1986年 | 94篇 |
1985年 | 64篇 |
1984年 | 43篇 |
1983年 | 38篇 |
1982年 | 28篇 |
1981年 | 36篇 |
1979年 | 23篇 |
1978年 | 22篇 |
1977年 | 23篇 |
1975年 | 18篇 |
1974年 | 17篇 |
1972年 | 15篇 |
1970年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 29 毫秒
991.
If association between the decline in physical performance and the decline in pulmonary function is confirmed, the SPPB could be used as a predictor for pulmonary functional declines in aging people because of its convenient use. This study aimed to elucidate the association of the SPPB with the pulmonary function test (PFT) to determine the usefulness of the SPPB as a predictor of PFT decline. The SPPB and PFT were performed on random sample nested in the Korean Longitudinal Study of Aging (KLoSA) panel, a national representative sample of aging people in Korea. Comparisons of adjusted means of forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), forced expiratory ratio (FER) defined as FEV1/FVC between normal and abnormal SPPB groups were performed using the t-test. The association between PFT and SPPB abnormality was examined using multiple logistic regression analysis. Additionally, the associations of gait speed and chair stand time with FEV1 and FVC were examined using multiple linear regression analysis. Five hundred and eighteen subjects were included in analysis. Approximately 43% (222/518) of the subjects were male and 65% (338/518) were 60 years or older. Adjusted means of FEV1 and FER were significantly or marginally lower when SPPB score was abnormal in both overall and non-smoking men (p=0.009 and 0.053 for overall, p<0.001 and p<0.080 for non-smokers), but FVC was lower only in non-smoking men (p=0.024). Abnormal SPPB score was significantly associated with abnormal PFT regardless of sex. (adjusted odds ratio=OR=3.76, 95%CI=1.96-7.22 for men, adjusted OR=2.11, 95%CI 1.28-3.47 for women). Gait speed was significantly or marginally associated with FEV1 and FVC in participants 60 years or older, regardless of sex. We conclude that abnormal SPPB score was associated with abnormal pulmonary function. Thus, the SPPB has the potential to be used as an early predictor of abnormal pulmonary function in clinical settings and epidemiological study. 相似文献
992.
993.
Koh JS Park JH Shin DH Youn TJ Oh IY Yoon CH Suh JW Cho YS Cho GY Chae IH Choi DJ 《The American journal of cardiology》2012,109(4):461-465
This study evaluated the risk factors of postprocedure cardiac troponin I (cTnI) increase and its effects on repeat revascularization and on overall clinical outcomes in patients with angina and normal preprocedural cTnI levels who underwent successful drug-eluting stent implantation. Postprocedure cTnI increase (≥0.5 ng/ml) was observed in 207 of 802 patients (25.8%). Patients with cTnI increase had more extensive coronary disease than patients without cTnI increase, which necessitated for the cTnI group more multilesion interventions and a longer total stent length. In multivariate analysis, total stent length (odds ratio 1.02, 1.01 to 1.03, p = 0.001) and use of glycoprotein IIb/IIIa inhibitors (3.07, 1.54 to 6.11, p <0.001) were identified as independent predictors of cTnI increase. During a median follow-up of 42 months, however, there were no significant between-group differences in Kaplan-Meier estimates of any repeat revascularization (24.8% vs 18.4%, hazard ratio 1.085, 0.723 to 1.627, p = 0.694) and major adverse cardiovascular events (27.0% vs 22.4%, 1.022, 0.703 to 1.485, p = 0.911). In conclusion, patients with postprocedure cTnI increase had more severe baseline coronary disease and received more complex interventional procedures. However, cTnI increase after successful drug-eluting stent implantation was not associated with an increased risk of repeat revascularization or of other adverse events. 相似文献
994.
995.
996.
997.
Generally, a true aneurysm is a dilatation of the vessel wall, whereas a pseudoaneurysm (PA) is a weakening or rent in a vessel wall, with contained rupture into the surrounding tissues. In the face, PAs of the facial artery are an extremely rare development after penetrating or blunt trauma. A 31-year-old woman presented with nontender, palpable, and firm lump that had been steadily increasing in size over a 4-week period. Examination confirmed a firm and spherical swelling in the left mandibular area, which was nonpulsatile. The patient presented with a mass on the upper part of her left chin 6 months after the injection of local anesthetics for dental treatment. After the procedure, a hematoma developed over the injection site, and it was treated with local ice. This case is unique in that the lesion seen using computed tomography and ultrasonography scanning had an unusual presentation. Ultrasonography revealed thrombi within the tumor, and color Doppler examination showed blood moving in the perivascular mass. During the operation via intraoral incision, a lesion was found as a dilation of the muscular branch of the facial artery. The facial artery was exposed, isolated, and tied off with a 2-0 white silk ligature. Histopathologic analysis determined that the content of the fragile cystic lesion was an organized thrombus and hematoma. As with any penetrating facial injury, local anesthetics can damage vessels and produce a PA. Therefore, we present a rare case of false facial artery aneurysm with no associated risk factors, which was nonpulsatile on presentation. 相似文献
998.
999.
1000.
Hsu KM Choi BH Ko CY Kim HS Xuan F Jeong SM 《Clinical implant dentistry and related research》2012,14(5):690-695
Background: Conflicting data exist on the outcome of placing Bio‐Oss® (Geitslich Pharm AG, Wolhausen, Switzerland) into extraction sockets. It is therefore relevant to study whether the incorporation of Bio‐Oss into extraction sockets would influence bone healing outcome at the extraction sites. Purpose: The aim of this study was to assess peri‐implant bone changes when implants were placed in fresh extraction sockets and the remaining defects were filled with Bio‐Oss particles in a canine mandible model. Materials and Methods: Six mongrel dogs were used in the study. In one jaw quadrant of each animal, the fourth mandibular premolars were extracted with an elevation of the mucoperiosteal flap; implants were then placed in the fresh extraction sockets and the remaining defects were filled with Bio‐Oss particles. After 4 months of healing, micro‐computed tomography at the implant sites was performed. Osseointegration was calculated as the percent of implant surface in contact with bone. Additionally, bone height was measured in the peri‐implant bone. Results: Average osseointegration was 28.5% (ranged between 14.8 and 34.2%). The mean crestal bone loss was 4.7 ± 2.1 mm on the buccal aspect, 0.4 ± 0.5 mm on the mesial aspect, 0.4 ± 0.3 mm on the distal aspect, and 0.3 ± 0.4 mm on the lingual aspect. Conclusion: The findings from this study demonstrated that the placement of implants and Bio‐Oss® particles into fresh extraction sockets resulted in significant buccal bone loss with low osseointegration. 相似文献