全文获取类型
收费全文 | 11583篇 |
免费 | 539篇 |
国内免费 | 165篇 |
专业分类
耳鼻咽喉 | 50篇 |
儿科学 | 357篇 |
妇产科学 | 410篇 |
基础医学 | 502篇 |
口腔科学 | 91篇 |
临床医学 | 3920篇 |
内科学 | 741篇 |
皮肤病学 | 44篇 |
神经病学 | 209篇 |
特种医学 | 1398篇 |
外科学 | 1313篇 |
综合类 | 1734篇 |
预防医学 | 428篇 |
眼科学 | 121篇 |
药学 | 562篇 |
8篇 | |
中国医学 | 86篇 |
肿瘤学 | 313篇 |
出版年
2023年 | 151篇 |
2022年 | 375篇 |
2021年 | 492篇 |
2020年 | 450篇 |
2019年 | 431篇 |
2018年 | 449篇 |
2017年 | 447篇 |
2016年 | 283篇 |
2015年 | 357篇 |
2014年 | 846篇 |
2013年 | 706篇 |
2012年 | 681篇 |
2011年 | 650篇 |
2010年 | 558篇 |
2009年 | 573篇 |
2008年 | 575篇 |
2007年 | 506篇 |
2006年 | 527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 | 57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 | 53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 |
1974年 | 22篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
Comparison of ultrasound transmission velocity with computed metacarpal radiogrammetry and dual-photon absorptiometry 总被引:2,自引:0,他引:2
A. Sili Scavalli M. Marini A. Spadaro V. Riccieri A. Cremona A. Zoppini 《European radiology》1996,6(2):192-195
The aim of our study was to evaluate the validity of a quantitative US technique for measuring the bone density of the proximal phalanges of the nondominant hand compared with computed metacarpal radiogrammetry and dual-photon absorptiometry (DPA) of the lumbar spine. Mean US bone velocity (UBV) correlated with mean metacarpal cortical index (MCI), with mean metacarpal bone density (MBD) and with bone mineral density (BMD) of the lumbar spine, whereas it was correlated negatively with age and menopause duration. The average UBV was significantly higher in premenopausal women than in postmenopausal women, and higher in normal lumbar DPA patients than in reduced lumbar DPA patients. We conclude that the US evaluation of the nondominant hand proximal phalanges may be a new alternative way for measuring bone mass in screening of osteoporosis.
Correspondence to: A. Sili Scavalli 相似文献
102.
José A. Budo M.D. 《Aesthetic plastic surgery》1996,20(6):489-493
The last decade has been marked by the development of liposuction. A better knowledge of the anatomy of fat tissue, together with an improvement in different devices, has made our results more predictable. However, such areas as the chin, anterior and inner thigh, and knee have remained difficult. This is especially true when large volumes of fat need to be removed. Blood loss has remained a problem as well. The development of ultrasound (U.S.) liposuction is a big step toward even more predictable results and to where blood loss can be negligible.Lipectron B.U.S. Endotron is a device manufactured by and available from MEDICA MAT s.a., Avenue Augustin Dumont 59, F-92240 MALAKOFF. 相似文献
103.
目的评价经超声引导成人与儿童肾活检术的方法和安全性。方法83例肾脏病患者超声引导下经皮穿刺活检,经右肾或左肾下极进针,方向自外下向内上,沿肾下极皮质取材。结果68例获取足够肾组织,总成功率及3针以内成功率分别为82%、53%,成人与儿童间无差异(P>0.05)。肾活检并发症儿童以疼痛为主,成人以血尿为主。结论超声引导下成人与儿童肾活检术是安全可靠的,其病理诊断对临床治疗具有明确的指导意义。 相似文献
104.
105.
Estimation of the amniotic fluid volume using the Cavalieri method on ultrasound images. 总被引:5,自引:0,他引:5
B Sahin T Alper A K?k?ü E Malatyalioglu R Kosif 《International journal of gynaecology and obstetrics》2003,82(1):25-30
OBJECTIVES: Presently, a design-based and practical method for measuring amniotic fluid volume (AFV) for routine clinical examinations has not been proposed. In this study we describe a new method, which combines the Cavalieri method with ultrasound imaging to estimate AFV. METHODS: We measured the AFVs of 14 women in the third trimester of pregnancy, and repeated our measurements three times for each woman. Parallel planimetric ultrasonographic images were obtained at every 2 cm along the longitudinal uterine axis. AFVs were calculated as the total of the multiples of the estimated cut surface areas by the section thickness. RESULTS: The mean estimated AFV was 380.5 cm3. The coefficient of error of each measurement was calculated and the mean was 0.108. The coefficient of correlation between the amniotic fluid index and our AFV estimations was 0.87. CONCLUSIONS: Design-based and efficient estimation of AFV is possible with the combination of consecutive ultrasound images and the Cavalieri method. 相似文献
106.
Kroke A Klipstein-Grobusch K Bergmann MM Weber K Boeing H 《Calcified tissue international》2000,66(1):5-10
Body mass is known to be related to measures of bone mineral density (BMD) as well as to parameters of quantitative ultrasound
(US). To examine the effect of the body compartment's fat mass and lean body mass on quantitative ultrasonic bone parameters,
data from a sample of 3241 German women were analyzed. Anthropometric measures, including skinfold thickness, were obtained
from standardized measurements, and fat and lean body mass were derived from classical regression formulas based on skinfold
measurements. Ultrasonic bone measurements were performed on the right os calcis, and speed of sound (SOS) and broadband ultrasound
attenuation (BUA) were determined. Women were grouped into pre- and postmenopausal status; postmenopausal women were further
stratified into ever and never hormone-replacement user. Correlation analysis indicated lean body mass to be stronger correlated
with BUA than fat mass in both pre- (r = 0.23; P= 0.0001) and postmenopausal women with (r = 0.19; P= 0.0001) and without hormone replacement therapy (HRT) (r = 0.26; p = 0.0001). SOS demonstrated very small or no associations
with body mass or its components. Multiple linear regression models were used to describe the relationship among body weight,
fat mass, and lean body mass on BUA after adjustment for confounding variables. Both in pre- and postmenopausal women lean
body mass was more strongly related to BUA than fat mass. However, body mass measures explained only small amounts of the
overall variance in BUA (R2= 1–3% in premenopausal women; R2= 1% postmenopausal with HRT; R2= 4–5% in postmenopausal women without HRT). In conclusion, the strong influence of body mass and its components previously
reported for BMD was not observed for quantitative ultrasonic bone parameters.
Received: 5 January 1999 / Accepted: 1 July 1999 相似文献
107.
108.
目的:观察高强度聚焦超声(HIFU)治疗中晚期肝癌的临床疗效。方法:采用FEP—BY01型高能聚焦超声热疗机,联合肝动脉检塞化疗(TACE)、抗癌中成药及支持对症治疗,对16例不能手术的肝癌进行综合治疗。结果:治疗后患者临床症状改善,疼痛缓解评分与疗前相比,差异有显著性(P〈0.05);B超显示回声增强,血流明显减少;AFP水平下降,无明显肝功能改变;无明显并发症发生。结论:HIFU治疗中晚期肝癌能缓解患者疼痛,改善生活质量,值得进一步研究。 相似文献
109.
A rare case of primary seminoma in the retroperitoneum is described. Ultrasound detected a huge hypoechoic mass and correlative
computed tomography showed a midline, homogeneous, lobulated mass in a man who presented for anuria.
Received: 1 April 1999; Revised: 28 June 1999; Accepted: 27 July 1999 相似文献
110.
A 48-year-old woman underwent total parathyroidectomy with autotransplantation into the left forearm due to secondary hyperparathyroidism.
Recurrence of hyperparathyroidism was observed 5 years later. B-mode high-resolution ultrasonography of the left forearm demonstrated
an ill-defined hypoechoic lesion. Frequency- and amplitude-encoded Doppler sonography revealed marked hypervascularity, which
was diagnostic for graft hyperplasia in association with the history of the patient. These findings were confirmed by scintigraphy
and histological examination of the excised graft.
Received: 22 November 1999; Revised: 8 February 1999; Accepted: 9 February 1999 相似文献