全文获取类型
收费全文 | 28881篇 |
免费 | 2786篇 |
国内免费 | 805篇 |
专业分类
耳鼻咽喉 | 290篇 |
儿科学 | 103篇 |
妇产科学 | 2122篇 |
基础医学 | 2985篇 |
口腔科学 | 825篇 |
临床医学 | 2601篇 |
内科学 | 635篇 |
皮肤病学 | 68篇 |
神经病学 | 1734篇 |
特种医学 | 1478篇 |
外国民族医学 | 24篇 |
外科学 | 6259篇 |
综合类 | 5149篇 |
现状与发展 | 10篇 |
预防医学 | 1253篇 |
眼科学 | 568篇 |
药学 | 1380篇 |
32篇 | |
中国医学 | 1167篇 |
肿瘤学 | 3789篇 |
出版年
2024年 | 45篇 |
2023年 | 485篇 |
2022年 | 719篇 |
2021年 | 1240篇 |
2020年 | 1125篇 |
2019年 | 866篇 |
2018年 | 850篇 |
2017年 | 1195篇 |
2016年 | 1347篇 |
2015年 | 1263篇 |
2014年 | 2363篇 |
2013年 | 2070篇 |
2012年 | 1979篇 |
2011年 | 2156篇 |
2010年 | 1695篇 |
2009年 | 1607篇 |
2008年 | 1535篇 |
2007年 | 1559篇 |
2006年 | 1301篇 |
2005年 | 1070篇 |
2004年 | 879篇 |
2003年 | 802篇 |
2002年 | 555篇 |
2001年 | 529篇 |
2000年 | 373篇 |
1999年 | 326篇 |
1998年 | 288篇 |
1997年 | 273篇 |
1996年 | 231篇 |
1995年 | 226篇 |
1994年 | 203篇 |
1993年 | 137篇 |
1992年 | 148篇 |
1991年 | 104篇 |
1990年 | 107篇 |
1989年 | 102篇 |
1988年 | 96篇 |
1987年 | 73篇 |
1986年 | 87篇 |
1985年 | 80篇 |
1984年 | 75篇 |
1983年 | 51篇 |
1982年 | 60篇 |
1981年 | 34篇 |
1980年 | 41篇 |
1979年 | 24篇 |
1978年 | 28篇 |
1977年 | 19篇 |
1976年 | 20篇 |
1973年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
1.
2.
3.
《Gait & posture》2022
BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η2 = 0.114) and liftoff (p = 0.122, η2 = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η2 = 0.648) and liftoff (p < 0.001, η2 = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η2 = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion. 相似文献
4.
目的 探讨肿瘤位置、最大直径及甲状腺外浸等临床病理特征与甲状腺癌前上纵隔淋巴结转移的关系。 方法 研究分析初次手术治疗的60例甲状腺乳头状癌患者临床及病理资料,运用检验临床病理特征与前上纵隔淋巴结阳性率的相关性。 结果 肿块位置、最大直径、数量、腺体外侵、受累腺叶数及Ⅵ区淋巴结转移等特征,以及患者年龄等相关因素中,只有VI区淋巴结对前上纵隔淋巴结状态有影响;60例患者前上纵隔淋巴结转移率为10/60(16.67%)。相关因素的前上纵隔淋巴结转移率对比:≥55岁vs <55岁(20% vs 16.36%, P<0.05);肿块位于下极 vs 上极 vs 中极(P>0.05);最大直径≥1.5 cm vs 最大直径<1.5 cm(18.18% vs 15.79, P>0.05);单灶 vs 多灶(21.88% vs 10.71%, P>0.05);单叶 vs 多叶(17.5% vs 15%, P>0.05);男性vs女性(20% vs 15.55%, P>0.05); Ⅵ区淋巴结阳性vs 阴性(24.43% vs 3.57%, P<0.05); 结论 总体来说,甲状腺乳头状癌前上纵隔淋巴结转移率较低。本研究发现VI区淋巴结状态可能与前上纵隔淋巴结转移相关,未来仍需大样本前瞻性的研究验证。 相似文献
5.
目的:观察理筋通督手法治疗颈性眩晕的临床疗效。方法:将120例颈性眩晕患者随机分成3组,理筋通督组、传统手法组及安慰剂组。理筋通督组采用理筋通督手法;传统手法组采用传统手法;安慰剂组口服维生素C。结果:理筋通督手法可显著减缓患者基底动脉舒张期最低血流速度(P0.05)。理筋通督组有效率为93.67%,传统手法组有效率为67.5%,安慰剂组有效率为17.5%,3组比较差异有统计学意义(P0.05),理筋通督组明显优于其他两组。结论:理筋通督手法治疗颈性眩晕临床疗效显著。 相似文献
6.
7.
目的对比动力髋螺钉(dynamic hip screw,DHS)治疗和股骨近端抗旋髓内钉(proximal femoral nail anti-rotation,PFNA)固定治疗老年股骨粗隆间骨折疗效。方法纳入本院收治的45例采用PFNA固定治疗的老年股骨粗隆间骨折患者作为研究组,研究时间为2017年11月-2018年11月;回顾性分析2016年11月-2017年11月在我院采用DHS治疗的45例老年股骨粗隆间骨折患者的临床资料,作为对照组。记录两组的相关手术指标,观察手术并发症情况。结果研究组的手术时间和骨折愈合时间均短于对照组,术中出血量明显少于对照组,术后疼痛VAS评分均明显低于对照组(P<0.05)。对照组的并发症发生率高于研究组(P<0.05)。结论PFNA固定治疗比DHS治疗老年股骨粗隆间骨折更加安全有效,值得临床借鉴和应用。 相似文献
8.
9.
Shina OranratanaphanMalika KengsakulSurang TriratanachatNakarin KitkumthornApiwat MutiranguraWichai Termrungruanglert 《Asian Pacific journal of cancer prevention》2020,21(10):2913-2917
Background: Self sampled HPV testing is a cervical cancer screening method . However, cytology in self-sampled specimen cannot be used as a triage test. Therefore, other methods for triage should be considered. CyclinA1 (CCNA1) promoter methylation has strong association with cervical precancerous and cancerous lesion. The objective of this study was to compare the diagnostic value of CCNA1 and self-sampled specimen for detecting high-grade cervical intraepithelial lesions or worse (CIN2+). Materials and Methods: A cross sectional study was conducted. Women with abnormal cytology or positive for high risk HPV (hrHPV) indicated for colposcopic examination were enrolled. Self-collected sampling for hrHPV DNA (SS-HPV) and CCNA1 were performed. hrHPV DNA testing was done by Cobas 4800 method. CCNA1 promoter methylation was detected by CCNA1 duplex methylation specific PCR. Histopathologic result as CIN2+ obtaining from colposcopic directed biopsy or excisional procedure was considered as positive a gold standard. The results of hrHPV and CCNA1 were reported as positive or negative. Sensitivity specificity, positive predictive value, and negative predictive value of SS-HPV and CCNA1 were calculated by comparing the results with the gold standard. Results: Two hundreds and eighty women were recruited. High-grade cervical lesions and cervical cancer (CIN2+) were diagnosed in 21.8% (61 cases) of the patients. The most common type of hrHPV was non 16, 18 subtype, followed by HPV16 and 18. CCNA1 was positive in 13 patients out of whom, twelve were CIN2+. Sensitivity of CCNA1 was 19.7 % and its specificity and accuracy were 99.5% and 82.14%, respectively. The sensitivity of SS-HPV was 70.5%, and its specificity and accuracy were 39.2% and 43.3%, respectively. Conclusion: Due to high specificity and positive predictive value of CCNA1, it can be used as alarming sign of having high-grade cervical intraepithelial lesions, especially in patient who has positive hrHPV DNA test based on self-collected sampling. 相似文献
10.