全文获取类型
收费全文 | 71601篇 |
免费 | 4196篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 972篇 |
儿科学 | 2240篇 |
妇产科学 | 1815篇 |
基础医学 | 10652篇 |
口腔科学 | 2354篇 |
临床医学 | 6616篇 |
内科学 | 12886篇 |
皮肤病学 | 1868篇 |
神经病学 | 7694篇 |
特种医学 | 3082篇 |
外科学 | 9713篇 |
综合类 | 272篇 |
一般理论 | 38篇 |
预防医学 | 5149篇 |
眼科学 | 1421篇 |
药学 | 4968篇 |
中国医学 | 114篇 |
肿瘤学 | 4006篇 |
出版年
2023年 | 397篇 |
2022年 | 306篇 |
2021年 | 673篇 |
2020年 | 712篇 |
2019年 | 788篇 |
2018年 | 1591篇 |
2017年 | 1339篇 |
2016年 | 1746篇 |
2015年 | 1445篇 |
2014年 | 1657篇 |
2013年 | 2984篇 |
2012年 | 3885篇 |
2011年 | 4377篇 |
2010年 | 2283篇 |
2009年 | 1519篇 |
2008年 | 4172篇 |
2007年 | 4355篇 |
2006年 | 4121篇 |
2005年 | 4047篇 |
2004年 | 3866篇 |
2003年 | 3851篇 |
2002年 | 3819篇 |
2001年 | 2920篇 |
2000年 | 3621篇 |
1999年 | 2062篇 |
1998年 | 681篇 |
1997年 | 562篇 |
1996年 | 431篇 |
1995年 | 373篇 |
1994年 | 381篇 |
1993年 | 372篇 |
1992年 | 442篇 |
1991年 | 351篇 |
1990年 | 374篇 |
1989年 | 416篇 |
1988年 | 338篇 |
1987年 | 319篇 |
1986年 | 341篇 |
1985年 | 384篇 |
1984年 | 410篇 |
1983年 | 353篇 |
1982年 | 310篇 |
1981年 | 270篇 |
1980年 | 250篇 |
1979年 | 328篇 |
1978年 | 242篇 |
1977年 | 261篇 |
1976年 | 244篇 |
1975年 | 221篇 |
1973年 | 248篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Oliver Schneider MD Christoph A. Stückle Elisabeth Bosch Corinna Gott Irenäus A. Adamietz 《Strahlentherapie und Onkologie》2004,180(8):502-509
BACKGROUND AND PURPOSE: The efficacy of radiation treatment (RT) for plantar heel pain has been reported repeatedly. Yet, the results referring to the pain relief rate, to long-term effects and prognostic factors are not consistent. In this paper, the effectiveness (pain relief rate and long-term results) and prognostic factors of RT for plantar heel pain have been investigated. PATIENTS AND METHODS: From January 2000 to October 2000, 62 patients (73 heels) with painful plantar heel spurs and a minimum pain history of 3 months were treated and evaluated in a prospective study. Mean age was 54 years (range 28-84 years). All patients were treated with a total dose of 5 Gy in seven fractions (= one series), given twice a week at a single-dose sequence of 0.25-0.25-0.5-1.0-1.0-1.0-1.0 Gy (10-MV photons, source-skin distance [SSD] 100 cm, direct portal, field size 12 x 17 cm). The mean duration of heel pain before RT was 26 weeks (= 6.5 months; range 3-120 months). By means of a visual analog scale (VAS) the patients had to self-assess the quantity of their heel pain once before, three times during and four times after RT at a longterm median follow-up of 28 and 40 months. Additionally, the patients had to assess their mechanical heel stress extent during RT. Effectiveness was estimated according to the patients' judgment of pain reduction. RESULTS: A significant reduction of heel pain extent measured by VAS has been observed already during the RT series (before RT: 6.3 +/- 1.5 vs. 3.8 +/- 2.1 at the end of RT; p < 0.001). 6 weeks after RT (FU 1) pain reduction (> 20%) was achieved in 60 heels (82.3%; n = 73), in 64 heels (91.4%; n = 70) after a mean follow-up of 28 months (FU 2), and in 61 heels (89.7%; n = 68) after a mean follow-up of 40 months (FU 3), respectively. Sufficient pain relief (> 80% compared to initial extent) was observed in 18/73 heels (24.6%) at FU 1 (FU 2: 42/70; 60.0%; FU 3: 37/68; 54.4%), including 13/73 heels (17.8%) with complete pain relief (FU 2: 39/70; 55.7%; FU 3: 36/68; 52.9%). Partial improvement (50-80% pain reduction) was observed in 27/73 heels (37.0%) at FU 1 (FU 2: 14/70; 20.0%; FU 3: 15/68; 22.1%), and minor partial improvement (20-50% pain reduction) in 15/73 heels (20.5%) at FU 1 (FU 2: 8/70; 11.4%; FU 3: 9/68; 13.2%), respectively. No change was seen in 13/73 heels (17.8%) at FU 1 (FU 2: 6/70; 8.6%; FU 3: 7/68; 10.3%). Older patients (p = 0.04) and patients who avoided heel stress during the period of RT (p < 0.01) demonstrated a better short-term response (FU 1); both effects were lost 28 and 40 months after RT. Moreover, significant differences in the extent of heel pain reduction by RT were observed in dependence on previous pain duration (at FU 2-3). CONCLUSION: The results confirm the high efficacy of RT in painful plantar spur and add new aspects to formerly published data concerning the time course of changes in heel pain reduction. Pain relief can be expected during and shortly after RT. In addition, the initial success can be transformed into effective long-term results > 2 years after RT; however, further improvement is not to be expected. As a new prognostic factor, the reduction of mechanical heel stress during RT may ameliorate the short-term results, whereas short heel pain history improves the long-term results. Especially for older patients, RT should be taken into consideration as primary treatment. 相似文献
62.
Dr. A.P. Anastasiadis H. Joneidi-Jafari T. Fehmer G. Muhr T. Kälicke 《Trauma und Berufskrankheit》2007,9(3):208-211
Isolated fractures of the metacarpal and phalangeal bones are common injuries of the upper extremities. They usually occur at the age of 10–40, whereas the highest incidence is observed in childhood. The results of treatment have an important impact for the practical value of the hand. This article aims to give a brief overview of the different fracture types and their treatment options. 相似文献
63.
Dorit Gräbsch 《MedR Medizinrecht》2007,25(6):VI-VIII
Ohne Zusammenfassung 相似文献
64.
Background
Hip dislocation in children with cerebral palsy (CP) is a common and severe problem. The dislocation can be avoided, by screening and preventive treatment of children with hips at risk. The aim of this study was to analyse the characteristics of children with CP who develop hip displacement, in order to optimise a hip surveillance programme. 相似文献65.
U. Bolm-Audorff S. Brandenburg T. Brüning H. Dupuis R. Ellegast G. Elsner K. Franz H. Grasshoff V. Grosser L. Hanisch B. Hartmann E. Hartung† K. G. Hering G. Heuchert M. Jäger J. Krämer Dr. A. Kranig E. Ludolph A. Luttmann A. Nienhaus W. Pieper K. D. Pöhl T. Remé D. Riede G. Rompe K. Schäfer S. Schilling E. Schmitt F. Schröter A. Seidler M. Spallek M. Weber 《Trauma und Berufskrankheit》2005,7(4):320-332
The first part of this serial paper dealt with the medical criteria used in evaluation of the clinical picture caused by physical stress and the evaluation of other candidate causes and was published in issue no. 3/2005 (pp. 711–752) of Trauma and Berufskrankheit. This follow-up paper (II) presents criteria to be used in the evaluation of whether it is necessary to give up the occupations putting the spine at risk and in estimation of the degree of disability. 相似文献
66.
67.
Robbert-Jan Roozeman Lasse Murtomäki Kyösti Kontturi 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,575(1):9-17
A recently introduced setup to measure the dynamic interfacial tension of expanding drops was used to compare the adsorption behaviour of a series of lipids at the electrified water∣dichloroethane interface. Phospholipids with saturated carbon chains of different length (DMPC, DPPC, DSPC, DAPC, DBPC), an unsaturated phospholipid (DOPC) and an ethanolamine (DSPE) were compared. It was found that the adsorption decreases with increasing chain length. Also, the increase of the flow rate reduces the degree of adsorption effectively. On the timescale of the experiments, the DSPE, DAPC and DBPC adsorption showed no potential dependence, whereas the adsorption of DOPC was stronger than that of the saturated lipids. Adsorption was modelled using the Langmuir adsorption isotherm; the potential dependence of adsorption is discussed. 相似文献
68.
H. Isoniemi J. Ahonen B. Eklund K. Höckerstedt K. Salmela E. von Willebrand P. Häyry 《Transplant international》1990,3(2):92-97
We have investigated the impact of triple drug immunosuppression on the occurrence of early inflammatory episodes, as detected by fine needle aspiration biopsy, and of episodes of clinical rejection during the immediate postoperative period. The prospective component of this study includes 128 consecutive first cadaveric renal transplant recipients receiving triple drug treatment consisting of azathioprine (Aza), cyclosporin (CyA) and methylprednisolone (MP). For controls we have used three historical groups: one immunosuppressed with Aza and MP (group A), another with CyA monotherapy (group B), and the third with CyA together with MP (group C) in equivalent drug dosages. On the average, 0.8 episodes of inflammation per patient were recorded during the immediate postoperative period of 30 days with triple drug treatment. This was significantly less than the 1.3 episodes in patients receiving Aza and MP (P<0.01), the 1.7 episodes in patients on CyA monotherapy (P<0.001), or the 1.6 episodes in patients receiving CyA together with MP (P<0.001). Although the first episode of inflammation commenced concurrently in each group and the peak intensity of inflammation was the same, the mean duration of inflammation was significantly shorter-2.7 days-under triple drug treatment than the 7.8–11.7 days for controls (P<0.001). The frequency of rejection episodes under triple treatment was also significantly lower-0.2 per patient-than the 0.8 per patient in controls (P<0.001). The first rejection episode occurred later in the triple drug treatment group-on the average, on day 15.2-than in the historical controls (on days 7.7–11.7). There was, however, no difference in the duration of rejection. There were no differences in patient survival between the four groups. Graft survival was 97% at 10 weeks for triple drug-treated recipients and 79%, 68%, and 87% for first grafts in groups A, B, and C, respectively. Disregarding a minor demographic bias for the triple drugtreated group with respect to preformed antibodies and preoperative dialysis treatment, the study suggests that the triple drug protocol, in the short run, is superior to any conceivable double drug combination or CyA monotherapy. 相似文献
69.
The mitochondrial intron rI1 is a self-splicing group-II intron of algal mitochondria that can be transferred into chloroplasts
from the green alga Chlamydomonas reinhardtii for in vivo investigations (Herdenberger et al. 1994). Thus, rI1 is a suitable system to compare in vitro and in vivo RNA
processing. Interestingly, rI1 shows correct RNA splicing, although typical cis-acting exon-sequences (IBS2, δ) of group-II introns are lacking. In order to examine the effect of these exon-intron interactions on splicing, we introduced
the endogenous mitochondrial IBS2 sequence in order to produce optimal IBS2-EBS2 base pairing. In addition, the first nucleotide
of the 3′exon (δ′) was substituted to create an optimal δ-δ′ interaction. Neither of the two mutations, nor a combination of both, had any effect on the precision of the splice-site
selection. Unexpectedly, introduction of IBS2 led to a reduction in the efficiency of the second splicing step in vitro but
not in vivo. These findings lead us to conclude that trans-acting factors are present in vivo to optimize splicing efficiency. The possibility is discussed that these factors may,
for example, stabilize tertiary intron structures that are a prerequisite for correct RNA processing. Furthermore, our data
indicate that similar trans-acting factors promote correct intron splicing in chloroplasts and mitochondria.
Received: 18 October / 4 December 1997 相似文献
70.
M. Bergström G. Westerberg G. Németh M. Traut G. Gross G. Greger H. Müller-Peltzer A. Safer S.-Å. Eckernäs A. Grahnér B. Långström 《European journal of clinical pharmacology》1997,52(2):121-128
Objective: The aim of the study was to investigate whether or not esuprone binds substantially to MAO-A in the human brain. Methods: In a randomised double-blind placebo-controlled study 16 male healthy volunteers were examined␣with positron emission tomography
(PET) with [11C]harmine. Eight of the volunteers were given daily doses of 800 mg esuprone, four were given bi-daily doses of 300 mg moclobemide,
and four volunteers were given placebo tablets. PET was performed before initiation of a 7-day treatment period. On day 7,
one investigation was made immediately before administration of the drug, representing 23 h after the previous day's treatment
for esuprone and 11 h after the last tablets of moclobemide. Further investigations were made 4 h and 8 h after the morning
dose on day 7. Results: PET showed a high degree of binding of [11C]harmine, a high-affinity ligand for MAO-A, before the start of treatment, and a marked and similar reduction after treatment
with esuprone and moclobemide. A slight tendency for normalisation of enzyme binding was observed at the last time point.
In the placebo group no change was observed. Plasma kinetics of esuprone showed a rapid elimination with a half-life of about
4 h. Conclusion: The study demonstrates that esuprone was comparable to moclobemide in its effect on MAO-A inhibition in the brain at the
doses given. This is an illustration of the potential of PET to monitor drug effects directly on target biochemical systems
in the brain in human volunteers, and the possibility of using these data, rather than pharmacokinetic data, for the determination
of dosing intervals.
Received: 21 August 1996 / Accepted in revised form: 22 November 1996 相似文献