全文获取类型
收费全文 | 1622篇 |
免费 | 107篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 93篇 |
妇产科学 | 41篇 |
基础医学 | 214篇 |
口腔科学 | 127篇 |
临床医学 | 149篇 |
内科学 | 239篇 |
皮肤病学 | 26篇 |
神经病学 | 89篇 |
特种医学 | 142篇 |
外科学 | 161篇 |
综合类 | 125篇 |
一般理论 | 1篇 |
预防医学 | 62篇 |
眼科学 | 48篇 |
药学 | 102篇 |
中国医学 | 7篇 |
肿瘤学 | 94篇 |
出版年
2023年 | 7篇 |
2022年 | 19篇 |
2021年 | 34篇 |
2020年 | 17篇 |
2019年 | 27篇 |
2018年 | 35篇 |
2017年 | 36篇 |
2016年 | 42篇 |
2015年 | 44篇 |
2014年 | 67篇 |
2013年 | 72篇 |
2012年 | 114篇 |
2011年 | 96篇 |
2010年 | 69篇 |
2009年 | 74篇 |
2008年 | 85篇 |
2007年 | 84篇 |
2006年 | 59篇 |
2005年 | 66篇 |
2004年 | 40篇 |
2003年 | 45篇 |
2002年 | 32篇 |
2001年 | 39篇 |
2000年 | 35篇 |
1999年 | 42篇 |
1998年 | 59篇 |
1997年 | 52篇 |
1996年 | 34篇 |
1995年 | 24篇 |
1994年 | 29篇 |
1993年 | 24篇 |
1992年 | 12篇 |
1991年 | 23篇 |
1990年 | 10篇 |
1989年 | 20篇 |
1988年 | 16篇 |
1987年 | 30篇 |
1986年 | 11篇 |
1985年 | 22篇 |
1984年 | 6篇 |
1983年 | 11篇 |
1982年 | 16篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 11篇 |
1975年 | 8篇 |
1970年 | 3篇 |
排序方式: 共有1746条查询结果,搜索用时 11 毫秒
1.
IntroductionThis study was designed to assess whether a dental caries management protocol combining a single application of 38% silver diamine fluoride (SDF) with comprehensive oral health education will successfully divert high-risk children from dental treatment under dental general anaesthesia (DGA), arrest active caries in primary teeth, and improve parent-reported child oral health–related quality of life (OHRQoL).MethodsChildren aged 2 to 10 years, who attended two public dental agencies in Victoria, Australia, and were unable to tolerate restorative treatments in the clinic setting, elected to participate in either a 38% SDF intervention protocol or, alternatively, referral for DGA. Follow-up examinations were completed at 6 months to assess caries progression, decayed missing filled tooth index, PUFA index (pulpal involvement, ulceration, fistula, abscess), DGA referral rates, and OHRQoL (Early Childhood Oral Health Impact Scale [ECOHIS]).ResultsOf the total sample, 89.5% of children (n = 102) [mean (SD) age, 4.1 (1.0) years] with 401 active carious lesions elected to participate in the 38% SDF protocol; 10.5% (n = 12) of parents opted for referral for treatment under DGA. The proportion of active caries subsequently arrested at follow-up (number of arrested lesions/number of lesions treated) was 0.78 (95% CI, 0.69 to 0.87). There was an 88% reduction in referrals for DGA in eligible children over the 6-month period. The 38% SDF intervention group showed a significant improvement in ECOHIS scores at follow-up (P < .001).DiscussionAdoption of the 38% SDF intervention protocol resulted in a significant reduction in the rate of preventable dental hospitalisations. Most parents opted against referral for DGA. Parent-reported OHRQoL for children improved significantly. 相似文献
2.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
3.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
4.
Ureteropelvic junction obstruction was noted in a newborn male infant with acro-pectoro-renal field defect. To our knowledge, this association has not previously been reported. Ultrasonography of the urinary tract should be performed on all children with aplasia of the pectoralis major muscle. 相似文献
5.
6.
7.
Kavita R Hegde Svitlana Kovtun Shambhu D Varma 《Journal of ocular pharmacology and therapeutics》2007,23(5):492-502
Ultraviolet (UV) radiation is one of the important cataract risk factors. The present studies examined the hypothesis that this effect is due to the UV penetration through the cornea and subsequent induction of a photochemical generation of reactive species of oxygen (ROS) in the aqueous and lens. The hypothesis was ascertained by rat lens organ culture studies conducted under UV (365 nm), with media containing micromolar levels of riboflavin, with and without pyruvate, the latter acting as an ROS scavenger. The implication of ROS in the UV-induced damage was confirmed by measurements of peroxide generation. Damage to the lens was assessed physiologically by measuring the decrease in its active transport of rubidium ions. Biochemically, it was assessed by measuring the lowering of adenosine triphosphate and glutathione. The incorporation of pyruvate in the medium protected the lens against these deleterious effects. That the beneficial effect of pyruvate is attributable to its ROS-scavenging property was proven by the peroxide depletion in its presence, commensurate with its own utilization in parallel. A protective effect of this keto acid against UV-induced tissue damage has been shown for the first time, suggesting its clinical usefulness against UV irradiation-induced pathologies. Hence, further studies on the possible protective effects of such alpha-keto acids against UV damage are in progress. 相似文献
8.
RS 39604: a potent, selective and orally active 5-HT4 receptor antagonist. 总被引:2,自引:0,他引:2 下载免费PDF全文
S. S. Hegde D. W. Bonhaus L. G. Johnson E. Leung R. D. Clark R. M. Eglen 《British journal of pharmacology》1995,115(6):1087-1095
1. Selective antagonism of 5-HT4 receptors may provide therapeutic benefit in certain disorders of the myocardium, alimentary and lower urinary tract. We now report on RS 39604, a novel and selective 5-HT4 receptor antagonist and compare its pharmacological properties with those of SB 204070. 2. In guinea-pig striatal membranes, both RS 39604 and SB 204070 inhibited specific binding of [3H]-GR 113808 in a concentration-dependent manner yielding pKi estimates of 9.1 and 10.9, respectively. RS 39604 displayed a low affinity (pKi < 6.5) for 5-HT1A, 5-HT2C, 5-HT3, alpha 1c, D1, D2, M1, M2, AT1, B1 and opioid mu receptors and moderate affinity for sigma 1, (pKi = 6.8) and sigma 2 (pKi = 7.8) sites. 3. In the rat isolated oesophagus, precontracted with carbachol, RS 39604 (30-300 nM) behaved as a competitive antagonist towards 5-HT-induced relaxation (pA2 = 9.3; Schild slope = 1.0). We and others have shown previously that SB 204070 behaves as an unsurmountable antagonist in this preparation (pA2 approximately 10.5). In the guinea-pig isolated ileal mucosa, RS 39604 (30 nM) antagonized 5-MeOT-induced increase in short-circuit current (pA2 = 9.1). 4. In anaesthetized vagotomized micropigs, RS 39604, administered by the i.v. or intraduodenal (i.duod.) route, produced dose-dependent inhibition of 5-HT-induced tachycardia (ID50 = 4.7 micrograms kg-1, i.v. and 254.5 micrograms kg-1, i.duod). At maximal doses of 30 micrograms kg-1, i.v. and 6 mg kg-1, i.duod., the inhibitory effects of RS 39604 lasted for more than 6 h.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6 下载免费PDF全文
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献
10.
Competitive control of the self-renewing T cell repertoire 总被引:1,自引:0,他引:1
We develop a mathematical model for the self-renewing part of the T cell
repertoire. Assuming that self-renewing T cells have to be stimulated by
immunogenic MHC-peptide complexes presented on the surfaces of
antigen-presenting cells, we derive a model of T cell growth in which
competition for MHC-peptide complexes limits T cell clone sizes and
regulates the total number of self-renewing T cells in the animal. We show
that for a sufficient diversity and/or degree of cross-reactivity, the
total T cell number hardly depends upon the diversity of the T cell
repertoire or the diversity of the set of presented peptides. Conversely,
for repertoires of lower diversity and/or cross-reactivity, steady-state
total T cell numbers may be limited by the diversity of the T cells. This
provides a possible explanation for the limited repertoire expansion in
some, but not all, mouse T cell re-constitution experiments. We suggest
that the competitive interactions described by our model underlie the
normal T cells numbers observed in transgenic mice, germ-free mice and
various knockout mice.
相似文献