全文获取类型
收费全文 | 3497篇 |
免费 | 228篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 138篇 |
妇产科学 | 152篇 |
基础医学 | 396篇 |
口腔科学 | 106篇 |
临床医学 | 511篇 |
内科学 | 567篇 |
皮肤病学 | 38篇 |
神经病学 | 288篇 |
特种医学 | 103篇 |
外科学 | 487篇 |
综合类 | 27篇 |
一般理论 | 5篇 |
预防医学 | 359篇 |
眼科学 | 28篇 |
药学 | 268篇 |
中国医学 | 3篇 |
肿瘤学 | 215篇 |
出版年
2022年 | 17篇 |
2021年 | 46篇 |
2020年 | 40篇 |
2019年 | 61篇 |
2018年 | 60篇 |
2017年 | 58篇 |
2016年 | 75篇 |
2015年 | 53篇 |
2014年 | 76篇 |
2013年 | 170篇 |
2012年 | 143篇 |
2011年 | 171篇 |
2010年 | 117篇 |
2009年 | 98篇 |
2008年 | 182篇 |
2007年 | 212篇 |
2006年 | 176篇 |
2005年 | 190篇 |
2004年 | 154篇 |
2003年 | 156篇 |
2002年 | 166篇 |
2001年 | 74篇 |
2000年 | 83篇 |
1999年 | 90篇 |
1998年 | 38篇 |
1997年 | 39篇 |
1996年 | 47篇 |
1995年 | 40篇 |
1994年 | 27篇 |
1993年 | 35篇 |
1992年 | 56篇 |
1991年 | 54篇 |
1990年 | 39篇 |
1989年 | 48篇 |
1988年 | 42篇 |
1987年 | 67篇 |
1986年 | 49篇 |
1985年 | 46篇 |
1984年 | 41篇 |
1983年 | 37篇 |
1982年 | 20篇 |
1981年 | 18篇 |
1979年 | 29篇 |
1978年 | 32篇 |
1977年 | 28篇 |
1976年 | 26篇 |
1975年 | 17篇 |
1974年 | 28篇 |
1973年 | 17篇 |
1972年 | 18篇 |
排序方式: 共有3734条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
Gunilla Movin-Osswald Per Karlsson Margareta Hammarlund-Udenaes Lars Farde 《Psychopharmacology》1994,114(2):248-256
The D2-dopamine receptor antagonist raclopride was administered to eight healthy male subjects, who had previously experienced akathisia following antipsychotic drugs. The influence of administration rate on onset, severity and duration of akathisia and on prolactin response was studied. Raclopride 3,5 or 9 mg or placebo (P) was administered as single IV infusions during 10 min (R10 min/3 mg), 1 h (R1h/5 mg) or 4 h (R4h/9 mg) according to a randomized double-blind design. Despite a 24-fold difference in administration rate a similar peak raclopride concentration of about 350 nmol/l was obtained after all three infusions. Three of the eight subjects experienced akathisia following R10 min/3 mg and R1h/5 mg, respectively. After R4h/9 mg seven subjects experienced akathisia of longer duration but not more severe than after the short infusions. The incidence and duration of akathisia seem to be mainly related to the plasma raclopride concentrations over time, whereas the rate of administration might be more important for the severity. A maximal prolactin response was induced which was not markedly affected by the rate of administration. 相似文献
5.
ERP evidence of impaired central nervous system function in virally suppressed HIV patients on antiretroviral therapy. 总被引:2,自引:0,他引:2
Linda L Chao Joselyn A Lindgren Derek L Flenniken Michael W Weiner 《Clinical neurophysiology》2004,115(7):1583-1591
OBJECTIVE: To examine the effects of human immunodeficiency virus (HIV) on central nervous system (CNS) function in patients receiving antiretroviral therapy (ART) who have suppressed viral loads. METHODS: Event-related brain potentials (ERPs) were recorded from 15 virally suppressed HIV patients and 15 age-, sex-, and education-matched controls while they performed a 3-stimulus auditory oddball task. The amplitude and latency of the P3a, P3b, and early auditory components were examined in HIV patients and controls. RESULTS: Virally suppressed HIV patients on ART were more depressed than controls, as determined by the Beck Depression Inventory (BDI). After controlling for the effects of depression, HIV patients had smaller P2, P3a, and P3b amplitudes and longer P3a and P3b latency than control subjects. BDI scores correlated positively with N1 latency in HIV patients and negatively with P3b amplitude in all subjects. CONCLUSIONS: These electrophysiological results suggest that, even in the absence of detectable levels of HIV in the peripheral blood, viral replication persists in the CNS and continues to cause disease in HIV patients on ART. 相似文献
6.
7.
Sven-Erik Strand Margareta Strandh Per Spanne 《Acta oncologica (Stockholm, Sweden)》1993,32(7):787-791
The need for direct methods of measuring the absorbed dose in vivo increases for systemic radiation therapy, and in more sophisticated methodologies developed for radioimmunotherapy. One method suggested is the use of mini-thermoluminescent dosimeters (TLD). Recent reports indicate a marked loss of signal when the dosimeters are used in vivo. We investigated the exterior surface of the dosimeters with scanning electron microscopy and the interior dosimeter volume with computed microtomography. The results show that the dosimeters initially have crystals uniformly embedded in the teflon matrix, with some of them directly exposed to the environment. After incubation in gel, holes appear in the dosimeter matrix where the crystals should have been. The computed microtomographic images show that crystals remain in the interior of the matrix, producing the remaining signal. We conclude that these dosimeters should be very carefully handled, and for practical use of mini-TLDs in vivo the dosimeters should be calibrated in equivalent milieus. An alternative solution to the problem of decreased TL efficiency, would be to coat the dosimeters with a thin layer, of Teflon, or other suitable material. 相似文献
8.
The concave and convex rib-vertebral angle (RVA) at levels T2–T12 was measured on AP radiographs of 19 patients with right convex idiopathic thoracic scoliosis and 10 patients with major thoracic right convex neuromuscular scoliosis. The difference between the angles on the concave and the convex sides, the RVAD, was calculated. The RVAs were also measured on radiographs from three animal groups in which spinal curves had been induced experimentally in a variety of ways. Group 1 comprised 16 rabbits that had been subjected to selective electrostimulation of the latissimus dorsi, the erector spinae and the intercostal muscles. Group 2 comprised four dead rabbits whose spines had been subjected to manual bending. Group 3 comprised eight rabbits that had undergone mechanical elongation of one rib. In both the idiopathic and the neuromuscular group, the convex RVA was smaller than the concave RVA between levels T2 and T8, with a maximal difference between T4 to T5. From T9 to T12 the concave RVA was smaller than the convex. The RVA in relation to the scoliotic segment, i.e. the apex level of the curve and the two neighbouring vertebrae above and below this level, showed similar results. With increasing Cobb angle the RVADs increased linearly with the greatest difference at the second vertebra above the apex. In the three experimental groups the pattern of the RVADs between T6 to T12 was basically similar to the findings of the clinical study. From the results of these clinical and experimental studies, it is concluded that the typical pattern of the RVAs on the concave and convex sides seems to be independent of the underlying cause of the spinal curvature. It is likely that the RVADs result from a passive mechanical adaptation of the ribs to the lateral curvature of the spine. 相似文献
9.
John Waller Marianne Angbratt Carina Blomberg Ann-Charlotte Kronhed Lasse Larsson Owe Löfman Margareta Möller Göran Toss Mats Foldevi Erik Trell 《Journal of medical systems》1997,21(1):33-47
Under designations like small areas action research and intervention, directed ‘ground-up’ health promotion and prevention in the population form an important part of the ongoing medical systems development. There is recent evidence of the success of community intervention against cardiovascular disease. In osteoporosis, however, there is still a lack of conclusive data on both the logics and logistics of such an approach. Since 1988, a county health policy program has been formulated and implemented in Östergötland, Sweden, following the principles and guidelines of the WHO HFA 2000 declaration. Vadstena (n ? 7,600) was chosen for a local and generalizable osteoporosis prevention project mediated by the primary care organization by means of health promotion and education in the community. In the present report we emphasize that community intervention is an important new advancement of the medical systems, where the basic research questions include operational and management aspects as equally vital and measurable requisites and results as other performance and outcome variables. We found that a community intervention trial against osteoporosis is both motivated and feasible and in this report wish to provide evidence on these crucial issues of logics and logistics. 相似文献
10.
K Daly G S Giebink P B Batalden R S Anderson C T Le B Lindgren 《The Pediatric infectious disease journal》1991,10(7):500-506
This double blind, placebo-controlled trial was designed to determine whether intervention with a stepped regimen of trimethoprim-sulfamethoxazole (TMP-SMX) and prednisone would prevent high risk children from developing chronic otitis media with effusion (OME) and recurrent acute otitis media. Forty-two children were enrolled, assigned to treatment with active drug or placebo and then examined at 2-week intervals. They received TMP-SMX (or placebo) during the first 2 weeks, TMP-SMX and prednisone (or placebo) during Weeks 3 and 4 for persistent OME and TMP-SMX (or placebo) for Weeks 5 and 6 if OME was still unresolved. After treatment 48% of active drug and 14% of placebo subjects resolved OME bilaterally (P less than 0.05). Active drug subjects also had fewer acute otitis media episodes than placebo subjects while receiving study treatment (P less than 0.01). Although this treatment regimen produced short term OME resolution, long term benefits were not demonstrated. 相似文献