全文获取类型
收费全文 | 2483939篇 |
免费 | 200620篇 |
国内免费 | 4580篇 |
专业分类
耳鼻咽喉 | 35870篇 |
儿科学 | 76133篇 |
妇产科学 | 65262篇 |
基础医学 | 349316篇 |
口腔科学 | 73647篇 |
临床医学 | 223746篇 |
内科学 | 491655篇 |
皮肤病学 | 50843篇 |
神经病学 | 209696篇 |
特种医学 | 99040篇 |
外国民族医学 | 903篇 |
外科学 | 373199篇 |
综合类 | 57248篇 |
现状与发展 | 2篇 |
一般理论 | 1023篇 |
预防医学 | 203056篇 |
眼科学 | 57630篇 |
药学 | 184256篇 |
4篇 | |
中国医学 | 4924篇 |
肿瘤学 | 131686篇 |
出版年
2019年 | 19817篇 |
2018年 | 27774篇 |
2017年 | 21396篇 |
2016年 | 23022篇 |
2015年 | 26173篇 |
2014年 | 37439篇 |
2013年 | 55712篇 |
2012年 | 76316篇 |
2011年 | 80315篇 |
2010年 | 46560篇 |
2009年 | 44275篇 |
2008年 | 74692篇 |
2007年 | 79468篇 |
2006年 | 79795篇 |
2005年 | 77980篇 |
2004年 | 74978篇 |
2003年 | 72093篇 |
2002年 | 69835篇 |
2001年 | 114610篇 |
2000年 | 118504篇 |
1999年 | 100167篇 |
1998年 | 28709篇 |
1997年 | 26221篇 |
1996年 | 26101篇 |
1995年 | 25154篇 |
1994年 | 23707篇 |
1993年 | 22118篇 |
1992年 | 80467篇 |
1991年 | 77454篇 |
1990年 | 74541篇 |
1989年 | 71808篇 |
1988年 | 66735篇 |
1987年 | 65634篇 |
1986年 | 62137篇 |
1985年 | 59160篇 |
1984年 | 44809篇 |
1983年 | 38136篇 |
1982年 | 23186篇 |
1981年 | 20590篇 |
1979年 | 41737篇 |
1978年 | 29266篇 |
1977年 | 24598篇 |
1976年 | 23046篇 |
1975年 | 24234篇 |
1974年 | 29920篇 |
1973年 | 28318篇 |
1972年 | 26445篇 |
1971年 | 24352篇 |
1970年 | 22987篇 |
1969年 | 21335篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Terry J DuBose 《Journal of ultrasound in medicine》2003,22(12):1420-1; author reply 1421-2
82.
83.
Zusammenfassung Viele gastrointestinale Tumoren werden im Rahmen multimodaler Therapiekonzepte behandelt. Für den Chirurgen ist die neoadjuvante, präoperative Behandlung von besonderem Interesse, da sie durch therapiebedingte Nebenwirkungen und Komplikationen zu einer Beeinflussung des postoperativen Verlaufs führen kann. Die neoadjuvante Radiochemotherapie ist fester Bestandteil der Therapie beim primären T4-Rektumkarzinom, beim Rektumkarzinomrezidiv und bei tief sitzenden primären Rektumkarzinomen. Durch Erhöhung der R0-Resektionsrate können die lokale Tumorkontrolle verbessert und die Überlebenszeit verlängert werden. Die postoperative Komplikationsrate ist dabei nicht wesentlich erhöht. In der Behandlung des primär resektablen Ösophaguskarzinoms deutet sich ein Vorteil der neoadjuvanten Radiochemotherapie im Vergleich zur alleinigen Chirurgie an. Beim lokal fortgeschrittenen Ösophaguskarzinom bietet die präoperative Radiochemotherapie häufig die einzige Chance zur Resektion, jedoch mit einer deutlich erhöhten postoperativen Morbidität und Mortalität. Die Wirksamkeit und Sicherheit einer neoadjuvanten Chemo- oder kombinierten Radiochemotherapie beim fortgeschrittenen Magenkarzinom wird derzeit im Rahmen von Studienprotokollen untersucht. 相似文献
84.
A survey of plants used as wild vegetables was conducted in four districts of Botswana in August and September 2005. The objective was to determine which wild plants were used as vegetables in the study area, and to document their cooking and preservation methods. Fourteen species representing seven families were mentioned as wild vegetables. In addition, six species from four families had other uses in traditional medicine. The implications of the documented processing methods on the retention of nutrients in the vegetables are discussed. 相似文献
85.
86.
Philippe Nickers Luc Coppens Jean de Leval Nicolas Jansen Jean-Marie Deneufbourg 《Radiotherapy and oncology》2006,79(3):329-334
BACKGROUND AND PURPOSE: To evaluate on 201 locally advanced prostatic cancers prospectively treated in a phase II trial, the efficacy of a combination of external beam radiotherapy (39.6 Gy) and (192)Ir low dose rate brachytherapy (Bt) (40-45 Gy). PATIENTS AND METHODS: Sixty-four patients were included in the intermediate prognosis group with only one of the following adverse factors (PSA > 10 ng/ml, Gleason score > or = 7 or clinical stage > or =T2b) and 137 in the unfavourable group when at least two of these factors were present. RESULTS: The actuarial 4 years biochemical no evidence of disease is 82.8% for the entire population. It is, respectively, 97 and 76% in the intermediate and unfavourable prognosis groups (P < 0.0001). Grade > or =3 late urinary complications occurred in 13 patients (6.5%). Eight patients (4%) presented late grade 2 rectal complications but no grades 3-5 was observed. CONCLUSIONS: Even if an alpha/beta of 1.5-3 Gy theoretically favours the use of a high dose rate mode of irradiation, the early results presented here are as good as those reported for similar groups of patients with high dose rate treatments. Late toxicity is identical but our urinary toxicity is within the less favourable and rectal toxicity within the most favourable results. We can postulate that while inducing very high hyperdosage regions (V150) mainly focused on the peripheral zone, most of the Bt techniques consist of a more ablative treatment. Many of the radiobiological studies on Bt did not in fact take into account the heterogeneity of irradiation inside the CTV. This study highlights the need to explore pulsed dose rate therapies, permanent implant and new available radioisotopes such as (169)Ytterbium that will offer the safety of low and lower dose rates. The actual late toxicity of the different Bt techniques is not yet inexistent indeed. 相似文献
87.
BCR-ABL activity and its response to drugs can be determined in CD34+ CML stem cells by CrkL phosphorylation status using flow cytometry. 总被引:2,自引:0,他引:2
A Hamilton L Elrick S Myssina M Copland H J?rgensen J V Melo T Holyoake 《Leukemia》2006,20(6):1035-1039
In chronic myeloid leukaemia, CD34(+) stem/progenitor cells appear resistant to imatinib mesylate (IM) in vitro and in vivo. To investigate the underlying mechanism(s) of IM resistance, it is essential to quantify Bcr-Abl kinase status at the stem cell level. We developed a flow cytometry method to measure CrkL phosphorylation (P-CrkL) in samples with <10(4) cells. The method was first validated in wild-type (K562) and mutant (BAF3) BCR-ABL(+) as well as BCR-ABL(-) (HL60) cell lines. In response to increasing IM concentration, there was a linear reduction in P-CrkL, which was Bcr-Abl specific and correlated with known resistance. The results were comparable to those from Western blotting. The method also proved to be reproducible with small samples of normal and Ph(+) CD34(+) cells and was able to discriminate between Ph(-), sensitive and resistant Ph(+) cells. This assay should now enable investigators to unravel the mechanism(s) of IM resistance in stem cells. 相似文献
88.
89.
We evaluated the acquisition and performance of a high-precision locomotor task in patients with Parkinson's disease (PD) and healthy subjects. All subjects walked on a treadmill and had to step repetitively as low as possible over an obstacle without touching it. During blocks 1 and 2, the subjects had full vision and received additional acoustic warning and feedback signals. During block 3, vision became restricted. Changes in foot clearance and the number of obstacle hits were evaluated. Initially, PD patients performed poorer and improved foot clearance slower. After task repetition, the groups performed similarly. Restricting vision deteriorated performance in both groups. The similar performance of PD patients after task repetition might indicate that adequate training could improve adaptive locomotor behavior in PD patients. 相似文献
90.
J Müller-Quernheim K I Gaede E Fireman G Zissel 《The European respiratory journal》2006,27(6):1190-1195
An increase in chronic beryllium disease (CBD) has been suggested due to higher industrial use of beryllium alloys. Since occupational CBD is a perfect phenocopy of sarcoidosis, it might be misdiagnosed as sarcoidosis. In the current it was hypothesised that CBD exists in cohorts of sarcoidosis patients. In a prospective case study, sarcoidosis patients were evaluated for potential beryllium exposure. In those patients in whom beryllium exposure was confirmed and beryllium hypersensitivity demonstrated, the diagnosis of sarcoidosis was rejected and corrected to CBD. In 84 patients seen for re-evaluation or making a diagnosis of sarcoidosis, beryllium exposure was recognised and a diagnosis of CBD was made in 34 out of 84 patients. The time lag between clinical diagnosis of sarcoidosis and the final diagnosis of CBD ranged 0-18 yrs (median 3 yrs) and the mean (range) age at time of diagnosis of CBD was 43.9(25-80) yrs. Beryllium-contaminated workplaces causing disease encompassed a wide spectrum of industries and technical trades in which beryllium-exposure is generally not perceived as a health hazard. In conclusion, chronic beryllium disease still belongs to the spectrum of differential diagnoses of granulomatous disorders. 相似文献