全文获取类型
收费全文 | 4899篇 |
免费 | 247篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 402篇 |
妇产科学 | 101篇 |
基础医学 | 571篇 |
口腔科学 | 95篇 |
临床医学 | 535篇 |
内科学 | 1192篇 |
皮肤病学 | 52篇 |
神经病学 | 315篇 |
特种医学 | 537篇 |
外国民族医学 | 1篇 |
外科学 | 463篇 |
综合类 | 51篇 |
一般理论 | 1篇 |
预防医学 | 304篇 |
眼科学 | 46篇 |
药学 | 213篇 |
中国医学 | 7篇 |
肿瘤学 | 248篇 |
出版年
2021年 | 66篇 |
2020年 | 48篇 |
2019年 | 54篇 |
2018年 | 81篇 |
2017年 | 52篇 |
2016年 | 57篇 |
2015年 | 76篇 |
2014年 | 87篇 |
2013年 | 169篇 |
2012年 | 162篇 |
2011年 | 165篇 |
2010年 | 149篇 |
2009年 | 142篇 |
2008年 | 173篇 |
2007年 | 191篇 |
2006年 | 166篇 |
2005年 | 156篇 |
2004年 | 184篇 |
2003年 | 146篇 |
2002年 | 160篇 |
2001年 | 141篇 |
2000年 | 170篇 |
1999年 | 145篇 |
1998年 | 182篇 |
1997年 | 154篇 |
1996年 | 159篇 |
1995年 | 105篇 |
1994年 | 98篇 |
1993年 | 102篇 |
1992年 | 90篇 |
1991年 | 89篇 |
1990年 | 85篇 |
1989年 | 134篇 |
1988年 | 106篇 |
1987年 | 119篇 |
1986年 | 76篇 |
1985年 | 97篇 |
1984年 | 57篇 |
1983年 | 69篇 |
1982年 | 52篇 |
1981年 | 36篇 |
1980年 | 44篇 |
1979年 | 53篇 |
1978年 | 41篇 |
1977年 | 32篇 |
1976年 | 47篇 |
1975年 | 33篇 |
1974年 | 22篇 |
1973年 | 22篇 |
1972年 | 23篇 |
排序方式: 共有5180条查询结果,搜索用时 0 毫秒
991.
Vicente Rey y Formoso Ricardo Barreto Mota Henrique Soares 《World journal of pediatrics : WJP》2022,(1):7-15
Background The hemostatic system is complex and evolves continuously since gestation and well into the adult years,in a process known as“developmental hemostasis.”Data sources A comprehensive review was performed after an extensive literature search on PubMed/MEDLINE concerning developmental hemostasis during the neonatal period.Relevant cross references were also included.Results Although part of a system,each component of the hemostatic system evolves differently,with many displaying both quantitative and qualitative age-related differences.This leads to drastic disparities between the coagulation system of neonates and both other children’s and adults’,while still maintaining a generally balanced and physiological hemostasis.The motives behind this process remain to be fully elucidated but may be,at least in part,related to non-hemostatic factors.Conclusions Knowledge regarding“developmental hemostasis”is essential for everyone caring for newborns or even children in general and in this review,we describe each hemostatic system component’s neonatal characteristics and age-related progression as well as explore some of the possible physiological motives behind the process. 相似文献
992.
No reliable non-invasive glucose monitoring devices are currently available. We implemented a mid-infrared (MIR) photoacoustic (PA) setup to track glucose in vitro in deep epidermal layers, which represents a significant step towards non-invasive in vivo glucose measurements using MIR light. An external-cavity quantum-cascade laser (1010-1095 cm(-1)) and a PA cell of only 78 mm(3) volume were employed to monitor glucose in epidermal skin. Skin samples are characterized by a high water content. Such samples investigated with an open-ended PA cell lead to varying conditions in the PA chamber (i.e., change of light absorption or relative humidity) and cause unstable signals. To circumvent variations in relative humidity and possible water condensation, the PA chamber was constantly ventilated by a 10 sccm N(2) flow. By bringing the epidermal skin samples in contact with aqueous glucose solutions with different concentrations (i.e., 0.1-10 g/dl), the glucose concentration in the skin sample was varied through passive diffusion. The achieved detection limit for glucose in epidermal skin is 100 mg/dl (SNR=1). Although this lies within the human physiological range (30-500 mg/dl) further improvements are necessary to non-invasively monitor glucose levels of diabetes patients. Furthermore spectra of epidermal tissue with and without glucose content have been recorded with the tunable quantum-cascade laser, indicating that epidermal constituents do not impair glucose detection. 相似文献
993.
JA Louwers M Kocken WA ter Harmsel RHM Verheijen 《BJOG : an international journal of obstetrics and gynaecology》2009,116(2):220-229
The aims of this review were to summarise the various methods of digital colposcopy and to provide an overview of their efficacy. We conducted a literature search and focused on papers that described a technique for colposcopy, other than conventional colposcopy, and compared this with conventional colposcopy and/or histology and included digitalisation of the process. All papers have been classified in one of the following categories: digital imaging and telecolposcopy, spectroscopy, computerised colposcopy, optical coherence tomography and confocal microcolposcopy. Among the most promising developments is spectroscopy, allowing a more or less automated analysis and interpretation of the colposcopic image. 相似文献
994.
Hirt D Urien S Ekouévi DK Rey E Arrivé E Blanche S Amani-Bosse C Nerrienet E Gray G Kone M Leang SK McIntyre J Dabis F Tréluyer JM;ANRS 《Clinical pharmacology and therapeutics》2009,85(2):182-189
Thirty-eight human immunodeficiency virus-1 (HIV-1)-infected pregnant women were administered tenofovir disoproxil fumarate (TDF; 300 mg)-emtricitabine (FTC; 200 mg) tablets: two at labor initiation and one daily for 7 days postpartum. Maternal, umbilical, and neonatal plasma tenofovir concentrations were measured by high-performance liquid chromatography and analyzed using a population approach. Data were described using a two-compartment model for the mother, an effect compartment linked to maternal circulation for cord, and a neonatal compartment disconnected after delivery. Absorption was greater for women delivering by caesarian section than for those delivering vaginally. The maternal 600 mg TDF administration before delivery produces the same concentrations as 300 mg administration in other adults. If the time elapsed between maternal administration and delivery is >or=12 h, two tablets of TDF-FTC should be readministered. Tenofovir showed good placental transfer (60%). Administering 13 mg/kg of TDF as soon as possible after birth should produce neonatal concentrations comparable with those observed in adults. 相似文献
995.
996.
997.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2001,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner. 相似文献
998.
D Satsou C Kouakam G Vaksmann D Klug S Kacet C Rey 《Archives des maladies du coeur et des vaisseaux》2001,94(5):527-530
The value of an implantable ECG monitor (Reveal TM Plus) is reported in a 12 year old child with unexplained syncopal episodes despite extensive investigations. Twenty-seven days after the implantation, ventricular tachycardia at 450/min was recorded at the first recurrence. This case shows that this type of monitoring can be particularly useful when an arrhythmia is thought to be the cause of syncope in a child and the initial investigation is negative. 相似文献
999.
1000.