全文获取类型
收费全文 | 8296篇 |
免费 | 683篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 310篇 |
妇产科学 | 151篇 |
基础医学 | 1394篇 |
口腔科学 | 141篇 |
临床医学 | 939篇 |
内科学 | 1522篇 |
皮肤病学 | 154篇 |
神经病学 | 939篇 |
特种医学 | 164篇 |
外科学 | 829篇 |
综合类 | 59篇 |
一般理论 | 7篇 |
预防医学 | 1026篇 |
眼科学 | 161篇 |
药学 | 611篇 |
中国医学 | 22篇 |
肿瘤学 | 497篇 |
出版年
2024年 | 13篇 |
2023年 | 120篇 |
2022年 | 194篇 |
2021年 | 412篇 |
2020年 | 253篇 |
2019年 | 403篇 |
2018年 | 404篇 |
2017年 | 294篇 |
2016年 | 299篇 |
2015年 | 330篇 |
2014年 | 418篇 |
2013年 | 463篇 |
2012年 | 735篇 |
2011年 | 774篇 |
2010年 | 361篇 |
2009年 | 345篇 |
2008年 | 494篇 |
2007年 | 462篇 |
2006年 | 442篇 |
2005年 | 360篇 |
2004年 | 339篇 |
2003年 | 289篇 |
2002年 | 277篇 |
2001年 | 28篇 |
2000年 | 18篇 |
1999年 | 32篇 |
1998年 | 44篇 |
1997年 | 36篇 |
1996年 | 27篇 |
1995年 | 24篇 |
1994年 | 11篇 |
1993年 | 27篇 |
1992年 | 17篇 |
1991年 | 10篇 |
1990年 | 10篇 |
1989年 | 14篇 |
1988年 | 12篇 |
1986年 | 11篇 |
1985年 | 16篇 |
1984年 | 16篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1981年 | 10篇 |
1980年 | 17篇 |
1958年 | 9篇 |
1957年 | 13篇 |
1956年 | 10篇 |
1955年 | 11篇 |
1954年 | 14篇 |
1949年 | 8篇 |
排序方式: 共有9002条查询结果,搜索用时 15 毫秒
81.
82.
Franklin Patricia D. Zheng Hua Bond Christina Lavallee Danielle C. 《Quality of life research》2021,30(11):3171-3178
Quality of Life Research - New informatics tools can transform evidence-based information to individualized predictive reports to serve shared decisions in clinic. We developed a web-based system... 相似文献
83.
Caitlin H. Douglass BHSc Karen Block PhD Danielle Horyniak PhD Margaret E. Hellard MBBS FRACP PhD FAFPHM Megan S. C. Lim PhD 《Health & social care in the community》2021,29(6):e308-e317
Young people from migrant and ethnic minority backgrounds are recognised as emerging priority populations for reducing alcohol and other drug (AOD)-related harms in Australia. Limited research has investigated how service providers address AOD challenges in migrant communities. In this qualitative study, we interviewed 15 service providers from AOD, migrant support, community and other health services in a diverse region of Melbourne. Interviews explored the challenges that service providers faced and the strategies they implemented to engage with young migrants in relation to AOD use. Thematic analysis was used to generate four themes: stigma as a barrier to service delivery, intergenerational differences between young people and parents, the need for outreach and establishing trust and understanding over time. Service providers believed that stigma prevented many young people from migrant backgrounds having open conversations about their AOD use with family members and professionals. Participants perceived that some parents had less AOD-related knowledge and lower English language proficiency than their children creating challenges for effective communication. Service providers recognised the importance of engaging with young people in settings where they felt comfortable rather than expecting them to approach their service. Participants also acknowledged the need to invest time in establishing trust and understanding with young migrants so they could facilitate conversations about AOD use as relationships evolved. Although service providers had a strong understanding of young people's needs, they found it challenging to build relationships in the context of funding and time constraints. Our results indicate the need for long-term funding and timelines that enable service providers to build strong relationships with young migrants, their families and their broader cultural communities to facilitate access to AOD support. 相似文献
84.
Tiziano Croci Marco Landi Danielle Gully Jean-Pierre Maffrand Gérard Le Fur Luciano Manara 《British journal of pharmacology》1997,120(7):1312-1318
- We investigated the effect of the non-peptide neurotensin (NT) antagonist SR 48692 on renal function in rats and the involvement of nitric oxide (NO) in the diuretic action of this compound.
- In fed animals, SR 48692 dose-dependently (0.5 to 12.5 mg kg−1, p.o., 0.03 to 1 mg kg−1, i.p. and 0.1 to 1 μg/rat, i.c.v.) increased urine output and urinary excretion of Na+, K+ and Cl− and reduced urine osmolality. The diuretic activity was also evident in water-deprived, fasted animals and in fasted, water-loaded rats.
- NT (0.1 μg/rat, i.c.v.) had no effect on urine output in fed rats, but reduced the diuretic action of SR 48692 (1 μg/rat, i.c.v.). The opposite result was obtained in fasted, water-loaded animals: NT dose-dependently (0.01 and 0.1 μg/rat, i.c.v.) inhibited diuresis and this effect was significantly inhibited by i.c.v. SR 48692. In this experimental condition, SR 48692 did not further increase the on-going diuresis.
- The NO synthesis inhibitor Nω-nitro-L-arginine methyl ester (L-NAME; 30 mg kg−1, i.p.) alone had no effect on urine output in fed rats but prevented the diuretic action of i.c.v. or i.p. SR 48692; L-arginine (1 g kg−1, i.p.) but not D-arginine (1 g kg−1, i.p.) restored the SR 48692-dependent increase in diuresis. L-NAME had no effect on furosemide-stimulated diuresis.
- Systemically administered L-NAME or i.c.v. NT in fasted, water-loaded rats significantly reduced water diuresis but this effect was no longer seen in animals given i.p. L-arginine. Rats receiving i.c.v. NT, whose diuresis was significantly reduced, also excreted less nitrates and nitrites in urine.
- Increased diuresis after central or systemic administration of SR 48692 to fed rats was paralleled by increased urinary excretion of nitrates and nitrites, this being consistent with peripheral enhancement of NO production after NT-receptor blockade by SR 48692. The increase in diuresis after furosemide also involved an increase of nitrates and nitrites in urine, but this effect was about half that attained with an equipotent diuretic dose of SR 48692.
- In fed rats, the NO donor isosorbide-dinitrate, reduced systolic blood pressure (unlike SR 48692 which did not affect blood pressure) but also dose-dependently (1 and 5 mg kg−1, i.p.) stimulated urine output.
- The overall effects of SR 48692 strongly support a link between the actions of endogenous NT, AVP and peripheral NO production in the modulation of renal excretion of water, Na+, K+ and Cl−.
85.
Jan M. West Danielle C. Humphris D. George Stephenson 《Journal of muscle research and cell motility》1995,16(3):267-284
Summary Long-(SL>6m) and short-sarcomere (SL<4m) fibres were isolated from the claw muscle of the yabby (Cherax destructor) during limb regeneration and at different stages of the moult cycle. Long-sarcomere fibres were more susceptible to the changes resulting from the moult-induced atrophy compared with the short-sarcomere fibres. Signs of atrophy included fibre erosion, loss of myosin filaments, a reduction in the diameter of myosin filaments and changes associated with the Z line. The intracellular structure of the fibres, however, remained intact in both fibre types. Fibres taken immediately prior to ecdysis could not be fully activated with Ca2+ or Sr2+ without breaking. In contrast fibres taken within 4 h after ecdysis could develop and maintain full force when activated by Ca2+ or Sr2+. The results suggest that loss of myofibrillar proteins via the moult-induced atrophy and/or events associated with fibre elongation may occur in the period just prior to ecdysis and that these changes may be responsible for the fibres inability to function during the premoult stage. Results from this study showed that short-sarcomere fibres add sarcomeres by at least two different mechanisms (1) transverse sarcomere splitting and (2) Z line splitting. Long-sarcomere fibres appear to be elongated by mechanism (s) other than those used by short-sarcomere fibres which possibly involve large electron dense structures which are positioned between the myofibrils and within the A and I bands. Results from the regenerating chelae limb bud showed that sarcomeres form from separate units comprising myosin filaments and actin filaments anchored into Z lines respectively. These sub-sarcomeric units then join together to form sarcomeres. Myofibril formation is aided by electron dense regions which are closely associated with the membrane system. These fibres although short in length and still within the non-functional limb bud could be activated by Ca2+ and Sr2+ suggesting that full fibre function exists before the chelae become functional. Regenerating muscle fibres consisted predominately of fibres with short-sarcomeres. 相似文献
86.
87.
88.
Yves Claustre Danielle De Peretti Philippe Brun Christiane Gueudet Nathalie Allouard Richard Alonso Jo?lle Lourdelet André Oblin Gabrielle Damoiseau Dominique Fran?on Marie-Fran?oise Suaud-Chagny Régis Steinberg Mireille Sevrin Hans Schoemaker Pascal George Philippe Soubrié Bernard Scatton 《Neuropsychopharmacology》2003,28(12):2064-2076
SSR181507 ((3-exo)-8-benzoyl-N-[[(2S)7-chloro-2,3-dihydro-1,4-benzodioxin-1-yl]methyl]-8-azabicyclo[3.2.1]octane-3-methanamine monohydrochloride) is a novel tropanemethanamine benzodioxane derivative that possesses high and selective affinities for D2-like and 5-HT(1A) receptors (K(I)=0.8, 0.2, and 0.2 nM for human D(2), D(3), and 5-HT(1A), respectively). In vivo, SSR181507 inhibited [(3)H]raclopride binding to D(2) receptors in the rat (ID(50)=0.9 and 1 mg/kg, i.p. in limbic system and striatum, respectively). It displayed D(2) antagonist and 5-HT(1A) agonist properties in the same concentration range in vitro (IC(50)=5.3 nM and EC(50)=2.3 nM, respectively, in the GTPgammaS model) and in the same dose range in vivo (ED(50)=1.6 and 0.7 mg/kg, i.p. on striatal DA and 5-HT synthesis, respectively, and 0.03-0.3 mg/kg, i.v. on dorsal raphe nucleus firing rate). It selectively enhanced Fos immunoreactivity in mesocorticolimbic areas as compared to the striatum. This regional selectivity was confirmed in electrophysiological studies where SSR181507, given acutely (0.1-3 mg/kg, i.p.) or chronically (3 mg/kg, i.p., o.d., 22 days), increased or decreased, respectively, the number of spontaneous active DA cells in the ventral tegmental area, but not in the substantia nigra. Moreover, SSR181507 increased both basal and phasic DA efflux (as assessed by microdialysis and electrochemistry) in the medial prefrontal cortex and nucleus accumbens, but not in the striatum. This study shows that the combination of D(2) receptor antagonism and 5-HT(1A) agonism, in the same dose range, confers on SSR181507 a unique neurochemical and electrophysiological profile and suggests the potential of this compound for the treatment of the main dimensions of schizophrenia. 相似文献
89.
90.