全文获取类型
收费全文 | 107854篇 |
免费 | 14195篇 |
国内免费 | 6100篇 |
专业分类
耳鼻咽喉 | 1151篇 |
儿科学 | 1545篇 |
妇产科学 | 1612篇 |
基础医学 | 10444篇 |
口腔科学 | 3033篇 |
临床医学 | 17104篇 |
内科学 | 16508篇 |
皮肤病学 | 1599篇 |
神经病学 | 7280篇 |
特种医学 | 4441篇 |
外国民族医学 | 68篇 |
外科学 | 12233篇 |
综合类 | 15338篇 |
现状与发展 | 28篇 |
一般理论 | 13篇 |
预防医学 | 9063篇 |
眼科学 | 2408篇 |
药学 | 9986篇 |
95篇 | |
中国医学 | 5326篇 |
肿瘤学 | 8874篇 |
出版年
2024年 | 479篇 |
2023年 | 2527篇 |
2022年 | 3522篇 |
2021年 | 4787篇 |
2020年 | 4285篇 |
2019年 | 3252篇 |
2018年 | 4434篇 |
2017年 | 4341篇 |
2016年 | 4242篇 |
2015年 | 5639篇 |
2014年 | 6890篇 |
2013年 | 6556篇 |
2012年 | 7845篇 |
2011年 | 8606篇 |
2010年 | 6481篇 |
2009年 | 5903篇 |
2008年 | 5922篇 |
2007年 | 5713篇 |
2006年 | 5588篇 |
2005年 | 5103篇 |
2004年 | 3566篇 |
2003年 | 3340篇 |
2002年 | 2809篇 |
2001年 | 2138篇 |
2000年 | 1946篇 |
1999年 | 1971篇 |
1998年 | 1368篇 |
1997年 | 1330篇 |
1996年 | 1090篇 |
1995年 | 959篇 |
1994年 | 751篇 |
1993年 | 529篇 |
1992年 | 569篇 |
1991年 | 508篇 |
1990年 | 433篇 |
1989年 | 403篇 |
1988年 | 382篇 |
1987年 | 308篇 |
1986年 | 301篇 |
1985年 | 249篇 |
1984年 | 172篇 |
1983年 | 125篇 |
1982年 | 81篇 |
1981年 | 76篇 |
1980年 | 56篇 |
1979年 | 108篇 |
1978年 | 55篇 |
1975年 | 50篇 |
1974年 | 61篇 |
1973年 | 40篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
空心螺钉治疗股骨颈骨折术后并发症的分析 总被引:9,自引:1,他引:8
目的探讨影响空心螺钉治疗股骨颈骨折术后早期并发症及中晚期股骨头缺血性坏死的因素。方法对1994年1月~2004年1月间应用空心螺钉治疗的116例股骨颈骨折患者进行回顾性总结,将患者性别、年龄、骨折类型、骨折复位情况、外伤至手术时间与骨折术后早期并发症及中晚期股骨头缺血性坏死间的关系进行统计学分析。结果116例患者获平均(3.2±2.5)年(1~11年)随访。术后早期并发症包括:骨折内固定失败6例,骨折周围再骨折2例,感染2例,下肢深静脉血栓6例。年龄是引起骨折术后早期并发症的主要因素之一;骨折术后早期并发症还与骨质情况及内固定技术有关。本组16例出现股骨头缺血性坏死,其坏死率为13.8%。造成股骨头缺血性坏死的因素主要是骨折类型,其次为骨折复位情况。结论①年龄大于60岁的患者股骨颈骨折术后早期并发症相对多。②对于骨折移位严重的高龄患者,建议行人工关节置换术。③内固定术应尽可能解剖复位、坚强牢靠,以减少术后股骨头缺血性坏死的发生。 相似文献
72.
73.
平阳霉素及糖皮质激素与激光联合治疗儿童颌面部血管瘤 总被引:5,自引:0,他引:5
目的探讨和评价平阳霉素及糖皮质激素与激光联合应用治疗儿童颌面部血管瘤的疗效。方法自2002年3月至2005年2月,采用平阳霉素及糖皮质激素与激光联合治疗儿童颌面部血管瘤78例,瘤体面积0.4cm×0.8cm~5.0cm×8.0cm。7~10d注射一次平阳霉素配制液,剂量为0.5mg/kg,3~5次为一个疗程,一个疗程的总量不超过40mg;小于6岁的患儿配合口服强地松;最后联合可调脉宽倍频ND:YAG激光治疗。结果治疗后经6个月至3年的随访,治愈和基本治愈率88.46%,有效率100%。结论平阳霉素及糖皮质激素与激光联合应用治疗儿童颌面部血管瘤是一种安全、有效、易行的治疗方法。 相似文献
74.
The purpose of this study was to investigate radiographic measurements in a cohort of patients with juvenile hallux valgus (with a hallux valgus angle > 15 degrees ) using standardized weightbearing x-rays compared with an age-matched control group. First metatarsal protrusion distance, metatarsus primus adductus angle, metatarsus adductus, first metatarsal cuneiform angle, calcaneal inclination angle, and talocalcaneal angles were assessed with discriminant functional analysis. A total of 37 sets of data were analyzed from patients with a mean age of 13.45 +/- 1.75 years. The study identified 2 significant components of juvenile hallux valgus: a positive first metatarsal protrusion distance (P <.001) and metatarsal primus adductus angle (P = .002). Discriminant functional analysis was then used to determine the best predictors of juvenile hallux valgus. This analysis allowed only 1 variable, metatarsal protrusion distance, as a predictor of whether juvenile hallux valgus was present (P < .001), with 94.3% accuracy. This study showed that a positive metatarsal protrusion distance is a significant component of juvenile hallux valgus. 相似文献
75.
Maher Saqqur MD Michael D. Hill MD MSc FRCPC Andrei V. Alexandrov MD Jayanta Roy MD Marcia Schebel BSc Andrea Krol BSc Zsolt Garami MD Ashfaq Shuaib MD FRCPC Andrew M. Demchuk MD FRCPC 《Journal of neuroimaging》2006,16(4):323-328
BACKGROUND: Stringent transcranial Doppler (TCD) criteria for diagnosing occlusion are needed for more reliable TCD performance at bedside in the acute stroke setting. SUBJECTS AND METHODS: At three academic stroke centers, we performed TCD examination for patients with symptoms of cerebral ischemia who underwent digital subtraction angiography (DSA). We used a standard insonation protocol with power M-mode Doppler (PMD) TCD (TCD 100 M, Spencer Technologies Inc., Seattle, WA). We collected mean flow velocity (MFV), pulsatility indices (PI), and power M-mode resistance signature (absent, high, or low) in symptomatic middle (MCA), anterior (ACA), posterior (PCA), and in affected (a), ipsilateral (i), and contralateral (c-lat) cerebral arteries. Ratios of aMCA/c-lat MCA, aMCA/iACA, and aMCA/iPCA MFV were subsequently calculated. PMD-TCD flow findings were evaluated with a receiver-operating characteristic (ROC) analysis for angiographically proven MCA occlusion. RESULTS: We studied 120 patients with acute cerebral ischemia with PMD-TCD examinations prior to or immediately after DSA. Lower aMCA velocities pointed to higher probability of occlusion (P= .055). The aMCA/iPCA MFV ratio was superior to the aMCA/iACA ratio and strongly predictive of occlusion at a threshold ratio of 0.5 (RR 2.31 CI(95) 2.13-2.51). High resistance or absent M-mode flow signatures in the proximal MCA were present in 87% of M1 and M2 MCA occlusions (probability 87%). In the presence of a low-resistance PMD signature, obtaining the aMCA/iPCA MFV ratio <0.5 increases probability of occlusion to 87%. Normal MFV ratios and low-resistance M-mode signatures are highly predictive of a negative angiogram for MCA occlusion. CONCLUSION: In acute cerebral ischemia, reliable criteria for proximal MCA occlusion have been developed based on combination of MFV ratios and M-mode flow resistance signatures. Validation of these criteria will require multicenter studies. 相似文献
76.
77.
目的探讨女性冠心病危险因素对女性冠心病发病率的影响。方法1000例内科门诊常规体检的45岁 ̄78岁女性,依据不同的危险因素分组,进行有危险因素及无危险因素组患病率比较;并将以上1000例按有无冠心病分为两组,比较两组平均血糖、血脂、CRP值。结果有家族史、绝经、肥胖、高血压、高血糖、吸烟、高脂饮食、体力活动减少者均较无以上因素者冠心病患病率高,并且P值均<0.05。结论家族史、绝经、肥胖、高血压以及糖尿病及糖耐量异常、吸烟、高脂饮食、体力活动减少均是冠心病危险因素,打鼾、长期口服避孕药、A型性格是否为冠心病危险因素不确定,可能与研究对象少有关。 相似文献
78.
Rosendo A. Rodriguez MD PhD Fraser Rubens MD MSc Carlos D. Rodriguez Howard J. Nathan MD 《Journal of neuroimaging》2006,16(2):126-132
OBJECTIVE: The application of intensity thresholds for embolus detection with transcranial Doppler (TCD) can exclude from analysis an unrecognized proportion of high-intensity transient signals (HITS))whose intensities are below the threshold. The lack of consistent threshold criteria between clinical trials may explain part of the discrepancy in the reported HITS counts. We investigated the effect of choosing different thresholds on the sensitivity and specificity of detecting HITS during cardiopulmonary bypass (CPB). METHODS: Two observers independently analyzed TCD recordings from 8 patients under CPB. Doppler signals were classified as true HITS, equivocal HITS, artifacts, and Doppler speckles according to preestablished criteria. The relative intensity of Doppler signals was measured by two different methods (TCD software vs manual). Receiver Operating Characteristic curves determined the optimal threshold for each of the two intensity methods. RESULTS: Reviewers achieved agreement in 96% of 2190 Doppler signals (kappa = 0.90). Relative intensities calculated with the TCD-software method were 3 dB (95% CI: 3.0-3.4) higher than the manual method. The optimal threshold was found at 10 dB (sensitivity: 99%; specificity: 90.8%) with the software method and at 7 dB with the manual method (sensitivity: 96%; specificity: 83%). The use of an intensity threshold 2 dB higher than the optimal increased the rejection of true HITS by 8% and 14%, respectively. CONCLUSIONS: Using intensity thresholds higher than the optimal for embolus detection decreases HITS counts. Choosing a threshold depends on the type of method used for measuring the signal intensity. Uniform threshold criteria and comparative studies between different Doppler devices are necessary for making clinical trials more comparable. 相似文献
79.
中西医结合治疗Leriche综合征78例 总被引:1,自引:1,他引:0
目的:总结中西医结合治疗Leriche综合征的方案.方法:回顾性总结Leriche综合征的临床治疗78例,均行人工血管主股或主髂动脉转流手术,术后静脉应用低分子右旋糖酐、复方丹参注射液和维脑路通.结果:手术结束后均能触及股动脉和动脉搏动,手术后7 d,患肢缺血症状均得到改善.手术后3月,患肢缺血症状消失,64例阳痿现象得到改善.彩色超声血管吻合口及人工血管内均未见血栓.结论:人工血管主股动脉转流或主髂动脉转流是治疗Leriche综合征较好的手术方案,围手术期合理应用扩血管、祛聚、活血化瘀药物,同时及时处理伴发疾病是提高临床治愈率和提高远期疗效的关键. 相似文献
80.
Ya Zumeng Gao Zhi Zhang Gang Wang Jianhua Tan Yinghui 《Otolaryngology--head and neck surgery》2006,135(3):458-462
OBJECTIVE: To reduce the incidence of sensory deficits and Frey's syndrome by modifying the traditional superficial parotidectomy. STUDY DESIGN: After raising the skin flap, the parotid gland fascia (PGF) was elevated to form a posterior pedicle fascial flap and then was replaced after the gland removal. The great auricular nerve (GAN) that runs within the PGF was not separated, so both the GAN and the PGF were preserved. Before this modification, the GAN and PGF were examined anatomically. The complication rates in the modified and control groups were compared. RESULTS: 1) The GAN, which runs within the thick and pycnotic PGF, trifurcates into postauricular, preauricular and lobule branches. The modification could be carried out practically based on the anatomy study. 2) Long-term sensory deficit was encountered in 13.3% of the control group, but 0% in the modified one. Frey's syndrome was suffered by 66.7% and 16.7% cases in the control and modified group respectively. The incidence of other complications was not significantly different. CONCLUSION: Our modification is practical. It decreases the complications significantly. EBM rating: B-3b. 相似文献