全文获取类型
收费全文 | 45147篇 |
免费 | 3210篇 |
国内免费 | 2407篇 |
专业分类
耳鼻咽喉 | 1511篇 |
儿科学 | 443篇 |
妇产科学 | 176篇 |
基础医学 | 5750篇 |
口腔科学 | 1021篇 |
临床医学 | 4484篇 |
内科学 | 3675篇 |
皮肤病学 | 210篇 |
神经病学 | 8720篇 |
特种医学 | 1459篇 |
外国民族医学 | 8篇 |
外科学 | 9142篇 |
综合类 | 6421篇 |
预防医学 | 778篇 |
眼科学 | 2532篇 |
药学 | 2429篇 |
32篇 | |
中国医学 | 1107篇 |
肿瘤学 | 866篇 |
出版年
2024年 | 116篇 |
2023年 | 721篇 |
2022年 | 1241篇 |
2021年 | 1677篇 |
2020年 | 1638篇 |
2019年 | 1446篇 |
2018年 | 1439篇 |
2017年 | 1625篇 |
2016年 | 1645篇 |
2015年 | 1584篇 |
2014年 | 2708篇 |
2013年 | 2652篇 |
2012年 | 2129篇 |
2011年 | 2438篇 |
2010年 | 2110篇 |
2009年 | 1997篇 |
2008年 | 2155篇 |
2007年 | 2183篇 |
2006年 | 1972篇 |
2005年 | 1721篇 |
2004年 | 1587篇 |
2003年 | 1397篇 |
2002年 | 1251篇 |
2001年 | 1119篇 |
2000年 | 922篇 |
1999年 | 880篇 |
1998年 | 859篇 |
1997年 | 773篇 |
1996年 | 635篇 |
1995年 | 582篇 |
1994年 | 494篇 |
1993年 | 473篇 |
1992年 | 489篇 |
1991年 | 418篇 |
1990年 | 406篇 |
1989年 | 346篇 |
1988年 | 299篇 |
1987年 | 294篇 |
1986年 | 287篇 |
1985年 | 371篇 |
1984年 | 315篇 |
1983年 | 223篇 |
1982年 | 253篇 |
1981年 | 218篇 |
1980年 | 194篇 |
1979年 | 131篇 |
1978年 | 84篇 |
1977年 | 89篇 |
1976年 | 63篇 |
1975年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
《Revista brasileira de otorrinolaringologia (English ed.)》2015,81(3):264-269
IntroductionThere is still no consensus in the literature as to the best acoustic stimulus for capturing vestibular evoked myogenic potential (VEMP). Low-frequency tone bursts are generally more effective than high-frequency, but recent studies still use clicks. Reproducibility is an important analytical parameter to observe the reliability of responses.ObjectiveTo determine the reproducibility of p13 and n23 latency and amplitude of the VEMP for stimuli with different tone-burst frequencies, and to define the best test frequency.MethodsCross-sectional cohort study. VEMP was captured in 156 ears, on the sternocleidomastoid muscle, using 100 tone-burst stimuli at frequencies of 250, 500, 1000, and 2000 Hz, and sound intensity of 95 dB nHL. Responses were replicated, that is, recorded three times on each side.ResultsNo significant difference was observed for p13 and n23 latencies of the VEMP, captured at three moments with tone-burst stimuli at 250, 500, and 1000 Hz. Only the frequency of 2000 Hz showed a difference between captures of this potential (p < 0.001). p13 and n23 amplitude analysis was also similar in the test–retest for all frequencies analyzed.Conclusionp13 and n23 latencies and amplitudes of VEMP for tone-burst stimuli at frequencies of 250, 500, and 1000 Hz are reproducible. 相似文献
2.
Background
Total knee arthroplasty is a treatment option for debilitating arthritis. In the postoperative period, patients experience moderate to severe pain affecting the rehabilitation, hospital stay, and patient satisfaction. This study aims at utilizing current best evidence to determine whether adductor canal block (ACB) or periarticular injection (PAI) is a better modality for managing short-term postoperative pain and opioid consumption.Methods
Embase, MEDLINE, HealthStar, Emcare, and PubMed were searched for randomized controlled trials from 1946 to August 2018, for literature addressing the comparison of ACB and PAI for pain management in the setting of total knee arthroplasty. A systematic review and meta-analysis were performed.Results
Six studies were included in our meta-analysis. When examining the combined visual analog scale (VAS) pain values for each group, analysis demonstrated greater reduction in scores for the PAI group, and the difference was statistically significant (P = .001). When comparing the VAS scores of subgroups analyzed at specific periods in time, there was a trend toward lower VAS scores in subgroups analyzed at 24 hours and 48 hours postoperatively (at rest and at movement) in the PAI group. Overall opioid consumption was lower in the PAI group, with demonstrated statistical significance (P = .03). When comparing the postoperative subgroups, there was a trend toward decreased opioid use in the PAI group, with 13.25% less opioid use at 48 hours and 9.5% less opioid use at 24 hours.Conclusion
PAI could significantly improve postoperative pain and opioid consumption when compared with ACB. Additional, high-quality studies are required to further address this topic. 相似文献3.
4.
《Journal of vascular and interventional radiology : JVIR》2020,31(1):150-154.e2
Thoracic endovascular aortic repair (TEVAR) for aneurysmal chronic dissection is often complicated by retrograde filling of the false lumen and dissected distal landing zone. A “cheese wire”-style fenestration of the dissection intimal flap can create a landing zone facilitating TEVAR. This technique successfully aided TEVAR in 3 patients with an average age of 57.3 years. Complications included type III endoleak requiring relining and renal artery occlusion requiring stent placement. Average duration of clinical follow-up was 19 ± 4 months. Imaging follow-up was 8 ± 10 months. All patients have survived for more than 1 year without aneurysm enlargement. 相似文献
5.
人胚雪旺细胞组织工程神经修复坐骨神经缺损的实验研究 总被引:1,自引:0,他引:1
目的:探索人胚雪旺细胞作为组织工程的种子细胞修复周围神经缺损的可行性。方法:通过组织工程方法用PLGA导管和polyglactin 910纤维负载人胚雪旺细胞预先构置好人工神经,然后用于修复大鼠20mm的坐骨神经缺损,并与神经切断后原位缝合以及用单纯的PLGA导管进行修复的实验组进行对照。通过活体肢体功能观察、靶器官肌肉测量、电生理检测、辣根过氧化物酶示踪、连续组织切片图像分析以及透射电镜等检查神经再生情况。结果:人工神经修复组神经再生良好,效果接近于神经原位缝合组,明显优于单纯的PLGA导管修复组。结论:人胚雪旺细胞构建的人工神经可以修复20mm的周围神经缺损。 相似文献
6.
Distribution patterns of transforaminal injections in the cervical spine evaluated by multi-slice computed tomography 总被引:1,自引:1,他引:0
Transforaminal injections are sometimes used for the diagnosis and treatment of painful conditions in the lumbar and to a lesser degree in the cervical spine. The technique is most often used when investigating/treating radiculopathy caused by degenerative disease. But how selective are the nerve root blocks? What possible structures other than the intended nerve root are affected from such injections? This study was undertaken in order to try to answer these questions, as no study focusing on the possible spread from the transforaminal selective nerve root blocks in the cervical spine has been performed earlier. In three groups of patients, each group including three patients, we injected three different volumes (0.6, 1.1 and 1.7 ml) with a transforaminal technique in the cervical spine. In all the injections, a small amount of contrast media was added. The spread of the injections were then investigated using multi-slice computed tomography with reconstructions. The imaging revealed a possible effect on other nerve roots than the intended ones when a larger volume was used for the root blocks. The spread was related to the injected volume as well as to local anatomy (size of foraminal area). In this study, only 0.6-ml injections could be accepted for being selective enough for diagnostic investigations. 相似文献
7.
Twenty-five women receiving sedation for outpatient hysteroscopic polypectomy were injected with 0.25% bupivacaine 10 mL (paracervical group) and another 25 received the same volume of saline (control group) at the cervical fornix. Both groups were given target-controlled propofol sedation during the procedure. More propofol (mg/min) was needed for adequate anesthesia in the control group compared to the paracervical group (6.5 versus 4.6). In addition, the postoperative pain scores were lower in the paracervical group than in the control group. Hemodynamic changes and postoperative side effects were similar in the two groups. This prospective, randomized, double-blind, placebo-controlled study confirmed the effective use of paracervical blocks. This approach has the effect of reducing the amount of intraoperative propofol and decreasing postoperative pain in outpatient hysteroscopic surgery. 相似文献
8.
Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear. 相似文献
9.
直肠癌术中保留盆腔自主神经对男性排尿及性功能的影响 总被引:5,自引:0,他引:5
目的探讨直肠癌根治术中保留盆腔自主神经(PANP)对男性排尿及性功能的影响。方法以问卷彤式调查48例直肠癌患者PANP手术和24例非PANP手术前、后的排尿功能和性功能,比较分析行直肠癌根治术的PANP组和非PANP组患者术后排尿和性功能指标及直肠癌的局部复发率。结果PANP组患者术后排尿及性功能部分指标优于对照组(P〈0.05),两组术后局部癌肿复发率比较尤显著性差异(P〉0.05)。结论直肠癌患者根治术中实施PANP,既不增加局部癌肿复发率,还可以改善患者的排尿和性功能,提高患者的生存质量。 相似文献
10.
Our group have studied a patient affected by a malignant schwannoma in the posterior tibial nerve. Schwannomas are uncommon neoplasms that originate from the Schwann cells of the peripheral nerves: the most common forms are benign. Malignant transformation is rarer. The therapy is surgical and the operation undertaken, if possible, should be the amputation. Alternatively, where amputation is not possible due to the specific localisation or due to patient refusal, the alternative must be the largest and most radical excision possible. 相似文献