全文获取类型
收费全文 | 11615篇 |
免费 | 585篇 |
国内免费 | 172篇 |
专业分类
耳鼻咽喉 | 51篇 |
儿科学 | 358篇 |
妇产科学 | 410篇 |
基础医学 | 504篇 |
口腔科学 | 89篇 |
临床医学 | 3949篇 |
内科学 | 742篇 |
皮肤病学 | 44篇 |
神经病学 | 209篇 |
特种医学 | 1433篇 |
外科学 | 1322篇 |
综合类 | 1737篇 |
预防医学 | 428篇 |
眼科学 | 121篇 |
药学 | 563篇 |
8篇 | |
中国医学 | 87篇 |
肿瘤学 | 317篇 |
出版年
2024年 | 31篇 |
2023年 | 157篇 |
2022年 | 426篇 |
2021年 | 502篇 |
2020年 | 456篇 |
2019年 | 432篇 |
2018年 | 449篇 |
2017年 | 447篇 |
2016年 | 285篇 |
2015年 | 357篇 |
2014年 | 844篇 |
2013年 | 706篇 |
2012年 | 681篇 |
2011年 | 651篇 |
2010年 | 559篇 |
2009年 | 573篇 |
2008年 | 575篇 |
2007年 | 506篇 |
2006年 | 526篇 |
2005年 | 399篇 |
2004年 | 341篇 |
2003年 | 269篇 |
2002年 | 182篇 |
2001年 | 196篇 |
2000年 | 179篇 |
1999年 | 158篇 |
1998年 | 126篇 |
1997年 | 133篇 |
1996年 | 104篇 |
1995年 | 96篇 |
1994年 | 90篇 |
1993年 | 56篇 |
1992年 | 66篇 |
1991年 | 57篇 |
1990年 | 39篇 |
1989年 | 48篇 |
1988年 | 43篇 |
1987年 | 43篇 |
1986年 | 60篇 |
1985年 | 54篇 |
1984年 | 36篇 |
1983年 | 45篇 |
1982年 | 70篇 |
1981年 | 62篇 |
1980年 | 33篇 |
1979年 | 36篇 |
1978年 | 64篇 |
1977年 | 25篇 |
1976年 | 41篇 |
1975年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(5-6):943-956
Treatment of hypertension has succeeded in preventing the complications attributable to pressure, including heart failure and the arteriolar complications such as brain hemorrhage and renal failure. Recent understanding that antihypertensive drugs have effects on lipoproteins and flow disturbances that may be important in atherosclerosis progression, and the recent development of drugs that are more effective in treating hyperlipidemia, have given impetus to the design of studies to test whether interventions are anti-atherosclerotic. Since studies depending on clinical endpoints by necessity consume vast resources, it is desirable to develop methods for measurement of atherosclerosis, in order to make it possible to conduct intervention studies efficiently. Because angiographic methods are costly and associated with risk, and many patients are unable or unwilling to undergo followup angiography at the end of a study, we are developing an atherosclerosis severity index based on clinical and noninvasive ultrasound assessment. This scale can be used as a surrogate outcome in place of, or complementary to angiographic measurement of atherosclerosis, to avoid costly loss of subjects in intervention studies. It has the additional advantage that it is suitable for repeated assessment over time, permitting the power of analyses such as life table analysis which look at time to development of endpoints. 相似文献
52.
53.
《Modern rheumatology / the Japan Rheumatism Association》2013,23(5):869-873
AbstractBackground. Juvenile Localized Scleroderma (JLS) causes functional disabilities and cosmetic deformities. Evaluation and follow-up of lesions are mandatory to understand the disease evolution. The objective of this study is to evaluate the usefulness of skin ultrasonography (US) in monitoring the response to treatment in JLS.Methods. Ten patients (age: 101,7 ± 66,2 months; 7 M, 3 F) affected by juvenile onset LS underwent sequential US exams (at baseline and after 6 months). Skin thickness was measured by using high-frequency US (18 MHz). All patients were evaluated both clinically (modified Rodnan Skin Score, mRSS) and by US (dermal thickness) at baseline and at 6 months. At baseline, 6/10 patients received 3 pulses of corticosteroids (solumedrol 30 mg/kg/day for 3 consecutive days, then oral steroids (1mg/kg), and methotrexate s.c. (15 mg/mq/week). After 6 months, 1/6 was switched to mycophenolate mofetil (25 mg/kg/day) due to inefficacy of MTX; 4/10 did not receive any further therapy.Results. US showed a thicker dermis and a thinned hypodermis in the lesional skin areas in respect to the healthy ones (p < 0.05). After treatment, in seven patients a clinical improvement (decrease of mRSS) was found. In six of these patients, US showed a decrease of dermal thickness showing a correlation with clinical data. Three patients who did not receive drugs showed unmodified images and clinical findings.Conclusion. US can help the assessment of skin and hypodermis in JLS and can detect an improvement of the lesions. 相似文献
54.
《Modern rheumatology / the Japan Rheumatism Association》2013,23(4):599-605
AbstractObjective. To compare hand US between systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients.Methods. Hands (1st–5th metacarpophalangeal [MCP] and 1st–5th proximal interphalangeal [PIP] joints) and wrists (radiocarpal and distal radioulnar joints) of 62 “no rhupus” SLE and 60 RA patients were compared through US (linear probe, 6–18 MHz). The findings were compared to clinical, functional, serological outcomes, and disease activity indices.Results. 2108 and 2040 joint recesses were evaluated in SLE and AR patients, respectively. Synovitis was found in 46.8% and 75% of wrists, 83.9% and 86.7% of MCPs and 58.1% and 70% of PIPs in the SLE and RA groups, respectively. More significant US findings were found in RA group. Greater values of synovitis (mm) in RA group were only found in the joint recesses of wrist (p < 0.001–0.002). In SLE group, US findings were associated with “puffy hands,” Health Assessment Questionnaire score and dynamometry. Twenty-two SLE patients (35.5%) had erosion in any of joints studied. SLE patient subgroup with US erosion was associated with hematological involvement and Jaccoud's arthropathy.Conclusions. US of “no rhupus” SLE and RA patients is different, especially in wrists. In SLE patients the clinical variable most associated with US findings was “puffy hands.” 相似文献
55.
《Systems biology in reproductive medicine》2013,59(2):179-184
The testes of 50 rats were placed in a cup filled with water and received 1 W/cm2 of ultrasound for 15 min. Fluid was collected from the seminiferous tubules and rete testis of the treated and control groups at 1, 8, 12, and 24 hr intervals. Ultrasound increased the sodium concentration in the fluid of the seminiferous tubules, decreased the sodium concentration in the fluid of the rete testis, increased the potassium concentration in the fluid of the rete testis, and decreased the potassium concentration in the fluid of the seminiferous tubules.Fourteen, slightly sedated, monkeys (Macaca fascicularis) were treated with 1/2 W/cm2 of ultrasound for 30 min. Water was used as the coupling agent for seven monkeys and 3% NaCl was used as the coupling agent for the other seven monkeys. The efficacy of ultrasound treatment in reducing sperm count to zero and achieving zero motility was increased when 3% NaCl was used. Sperm count was at the level of presonication after 20 weeks when water was used as a coupling agent. 相似文献
56.
Neuronal development is known to be a dynamic process that can be modulated by presenting guidance cues to neuronal cells. We show that ultrasound, when applied at pulsed settings and with intensities slightly greater than clinical diagnosis levels, can potentially act as a repulsive cue for modulating neuronal growth dynamics. Using differentiated Neuro-2a cells as the model, we have examined in vitro how neuronal development can change during and after exposure to 1-MHz ultrasound for different acoustic settings. Neurite retraction and cell body shrinkage were found in neuronal cells over a 10-min exposure period with 1.168 W/cm2 spatial-peak, time-averaged intensity (based on 0.84 MPa peak acoustic pressure, 100-cycle pulse duration, and 500-Hz pulse repetition frequency). These effects were found to result in instances of neuronal cell body displacement. The extent of the effects was dependent on acoustic intensity, with peak acoustic pressure being a more important contributing factor compared with pulse duration. The morphological changes were found to be non-destructive, in that post-exposure neurite outgrowth and neuritogenesis were respectively observed in neurite-bearing and neurite-less neuronal cells. Our results also showed that mechanotransduction might be involved in mediating ultrasound-neuron interactions, as the morphological changes were suppressed if stretch-activated ion channels were blocked or if calcium messenger ions were chelated. Overall, these findings suggest that ultrasound can potentially influence how neuronal cells develop through modifying their cytomechanical characteristics. 相似文献
57.
A 3-day-old girl in good health was referred to our department for the evaluation of an abdominal mass detected at birth. Prenatal ultrasound (US) examinations had shown no anomaly. US examination revealed the presence of a hypoechoic and corpusculated cystic formation of about 8 × 5 × 4 cm located in the mid region of the abdomen. The uterus was not visible and the kidneys were normal with no sign of hydronephrosis. The ovaries were normal. Physical examination confirmed US findings revealing the presence of a curved membrane which covered the vaginal opening. Based on these findings, the patient was diagnosed to have hydrometrocolpos. Hymenectomy was performed and about 100 ml of milky fluid was subsequently removed by aspiration. The patient presented no other congenital anomalies and US follow-up showed a normal structure of the uterus. 相似文献
58.
Muscle injuries can be classified into strain injuries and contusions. Depending on the type of injury, different complications may occur, which in turn can be divided into early, intermediate and delayed complications. A prompt diagnosis of complications allows early treatment and permits to avoid harmful sequelae. Imaging studies, ultrasonography in particular, allow (recognizing) the assessment of complications whenever clinically suspected. In this article the most frequent complications of muscle injuries are presented. 相似文献
59.
60.
超声医学年轻医生教育培训亟待转型和加强 总被引:1,自引:0,他引:1
随着超声医学的飞速发展和就诊模式的改变,以及无创伤性、可重复性等优势,临床医生及患者对超声的需求急剧增加,超声检查已成为临床常规检查方法之一。但是超声医生培养模式已远远跟不上时代需要,因此迫切需要转型和加强。本文根据多年来培养研究生、住院医生、社区医生的经验和教训,以及本院关于住院医师医学影像专业培训计划,制定超声医生超声医学科一、三、五年轮转规划,实施以年轻超声医师为中心的超声医学人才培养模式。 相似文献