全文获取类型
收费全文 | 5907篇 |
免费 | 563篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 58篇 |
儿科学 | 198篇 |
妇产科学 | 133篇 |
基础医学 | 720篇 |
口腔科学 | 95篇 |
临床医学 | 830篇 |
内科学 | 965篇 |
皮肤病学 | 140篇 |
神经病学 | 326篇 |
特种医学 | 677篇 |
外科学 | 718篇 |
综合类 | 203篇 |
一般理论 | 3篇 |
预防医学 | 595篇 |
眼科学 | 47篇 |
药学 | 413篇 |
中国医学 | 24篇 |
肿瘤学 | 334篇 |
出版年
2021年 | 78篇 |
2020年 | 63篇 |
2019年 | 81篇 |
2018年 | 111篇 |
2017年 | 64篇 |
2016年 | 91篇 |
2015年 | 88篇 |
2014年 | 167篇 |
2013年 | 212篇 |
2012年 | 278篇 |
2011年 | 316篇 |
2010年 | 169篇 |
2009年 | 163篇 |
2008年 | 283篇 |
2007年 | 297篇 |
2006年 | 226篇 |
2005年 | 265篇 |
2004年 | 202篇 |
2003年 | 161篇 |
2002年 | 179篇 |
2001年 | 151篇 |
2000年 | 171篇 |
1999年 | 160篇 |
1998年 | 113篇 |
1997年 | 89篇 |
1996年 | 90篇 |
1995年 | 98篇 |
1994年 | 92篇 |
1993年 | 84篇 |
1992年 | 135篇 |
1991年 | 127篇 |
1990年 | 125篇 |
1989年 | 128篇 |
1988年 | 130篇 |
1987年 | 131篇 |
1986年 | 118篇 |
1985年 | 141篇 |
1984年 | 100篇 |
1983年 | 91篇 |
1982年 | 60篇 |
1981年 | 37篇 |
1980年 | 44篇 |
1979年 | 51篇 |
1978年 | 47篇 |
1977年 | 36篇 |
1976年 | 50篇 |
1975年 | 35篇 |
1974年 | 36篇 |
1972年 | 27篇 |
1971年 | 29篇 |
排序方式: 共有6479条查询结果,搜索用时 234 毫秒
21.
Morphine place conditioning is differentially affected by CCKA and CCKB receptor antagonists. 总被引:2,自引:0,他引:2
In the present study we have examined the interaction between the selective cholecystokinin (CCK)A and CCKB receptor antagonists, devazepide and L365-260 on morphine conditioned place preference (CPP). Using an unbiased procedure, morphine (1.5 mg/kg) produced a reliable CPP which was observed irrespective of the conditioning compartment type. Pretreatment with devazepide (0.001-0.01 mg/kg s.c.) produced a dose related attenuation of this response. At higher doses (0.1-1 mg/kg) this antagonism became variable and dependent on the training compartment with blockade only observed when conditioning was to the white/rough textured environment. This profile has also been reported for the serotonin (5-HT)3 receptor antagonist ondansetron. The CCKB antagonist L365-260 (0.000001-0.01 mg/kg) failed to antagonize the morphine CPP, if anything a mild potentiation was observed. To study this further we examined the interaction between L365-260 (0.01 mg/kg) and a subthreshold dose of morphine (0.3 mg/kg). At these doses neither drug elicited CPP, however when co-administered a significant CPP was recorded. Finally, L365-260 at 1 mg/kg induced a mild but significant CPP when administered alone. These results suggest a differential role of CCK receptor subtypes on reward-related behaviour and complement previous studies suggesting bimodal effects of CCK systems on mesolimbic dopamine function. 相似文献
22.
G Affleck H Tennen S Urrows P Higgins 《Journal of consulting and clinical psychology》1992,60(1):119-126
For 75 consecutive days, 54 Ss with rheumatoid arthritis supplied daily reports of their mood and joint pain. After aggregating daily reports, the relation between chronic mood and chronic pain remained statistically significant when controlling for neuroticism, depression, disease activity, disability, and characteristic responses to increasing pain. Findings of a path analysis suggest that (a) individuals higher in neuroticism experience more chronic distress regardless of their responses to pain, their pain intensity, and depressive symptomatology, and (b) the relation between neuroticism and chronic pain is mediated by the propensity of high-neuroticism individuals to catastrophize their pain. Within-subject analyses that controlled for autocorrelation and linear trends in the time series revealed that 40% of the Ss experienced significantly worse moods on more painful days. Although individuals higher in neuroticism reported more intense pain and more negative mood, their daily mood was less strongly linked to their daily pain. 相似文献
23.
Mesenteric infarction secondary to tumor emboli from primary aortic sarcoma. Guidelines for diagnosis and management 总被引:3,自引:0,他引:3
Primary aortic tumors are rare, difficult to diagnose, and often fatal. This case and a review of the literature identified aortic tumors as a potential source of emboli leading to acute mesenteric insufficiency. The case showed the efficacy of magnetic resonance imaging in diagnosing and determining the extent and location of an aortic tumor. 相似文献
24.
25.
26.
27.
H Angus-Leppan GA Lambert J Michalicek 《Cephalalgia : an international journal of headache》1997,17(6):625-630
Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches. 相似文献
28.
This paper reports the findings from the first 2 years of the Belfast Youth Development Study. The Belfast Youth Development Study is a 5-year longitudinal investigation of the onset and development of adolescent drug using behaviours, the findings of the first 2 years from the study in relation to drug use patterns among the young people participating in the research are reported here. The findings show that while the majority of young people have not yet used an illicit substance, the study has seen a substantial increase in the numbers using such substances between year 1 and year 2. Boys still make up the majority of drug users in this period but there has been a substantial increase in the number of girls using illicit drugs and, more generally, an increase in the frequency of use among all those using such substances during this period. 相似文献
29.
In patients with PG-dependent renal function, NSAID administration
constantly reduces GFR and RBF in a dose-dependent fashion. In this
situation, the risk of overt acute renal failure is high and should be
taken into proper account. In contrast, the incidence of NSAID-related
renal structural alterations appears to be very low, yet the absolute
number of patients may be significant considering the wide use of such
drugs. Concerning the antiproteinuric effect of NSAIDs, the unfavourable
ratio risk/benefit does not seem to support their indication in proteinuric
nephropathies. The development of PGHS-2 selective inhibitors is promising,
and may open new therapeutical strategies in the treatment of the
progression of renal disease.
相似文献
30.
Non-operative management of retroperitoneal fibrosis 总被引:1,自引:0,他引:1
It is generally recognized that in many patients the ureteric obstruction and other manifestations of non-malignant retroperitoneal fibrosis will respond to treatment with corticosteroids. However, most surgeons are reluctant to use steroids as the primary treatment for patients with this condition, mainly because of the risk of mismanagement of malignant retroperitoneal fibrosis. Our experience in the care of 17 patients with non-malignant retroperitoneal fibrosis has led us to believe that an initial non-surgical approach is both safe and preferable. 相似文献