全文获取类型
收费全文 | 149971篇 |
免费 | 13078篇 |
国内免费 | 9481篇 |
专业分类
耳鼻咽喉 | 1224篇 |
儿科学 | 1888篇 |
妇产科学 | 2487篇 |
基础医学 | 17233篇 |
口腔科学 | 2589篇 |
临床医学 | 19086篇 |
内科学 | 24014篇 |
皮肤病学 | 1917篇 |
神经病学 | 8243篇 |
特种医学 | 5450篇 |
外国民族医学 | 72篇 |
外科学 | 16532篇 |
综合类 | 23063篇 |
现状与发展 | 28篇 |
一般理论 | 8篇 |
预防医学 | 9573篇 |
眼科学 | 4090篇 |
药学 | 14916篇 |
148篇 | |
中国医学 | 7241篇 |
肿瘤学 | 12728篇 |
出版年
2024年 | 437篇 |
2023年 | 2220篇 |
2022年 | 5579篇 |
2021年 | 7116篇 |
2020年 | 5268篇 |
2019年 | 4864篇 |
2018年 | 4937篇 |
2017年 | 4486篇 |
2016年 | 4249篇 |
2015年 | 6321篇 |
2014年 | 7844篇 |
2013年 | 7603篇 |
2012年 | 11009篇 |
2011年 | 11866篇 |
2010年 | 7467篇 |
2009年 | 6014篇 |
2008年 | 7960篇 |
2007年 | 7906篇 |
2006年 | 7845篇 |
2005年 | 7577篇 |
2004年 | 5343篇 |
2003年 | 5084篇 |
2002年 | 4238篇 |
2001年 | 3661篇 |
2000年 | 3612篇 |
1999年 | 3648篇 |
1998年 | 2375篇 |
1997年 | 2278篇 |
1996年 | 1656篇 |
1995年 | 1531篇 |
1994年 | 1347篇 |
1993年 | 861篇 |
1992年 | 1286篇 |
1991年 | 1118篇 |
1990年 | 966篇 |
1989年 | 856篇 |
1988年 | 741篇 |
1987年 | 702篇 |
1986年 | 548篇 |
1985年 | 498篇 |
1984年 | 275篇 |
1983年 | 200篇 |
1982年 | 140篇 |
1981年 | 134篇 |
1980年 | 94篇 |
1979年 | 141篇 |
1978年 | 69篇 |
1976年 | 60篇 |
1975年 | 60篇 |
1974年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Twenty patients with major depressive disorder were studied with evoked potential (EP) topographic mapping after receiving placebo, imipramine, or amoxapine for 2 days in a random-assignment, double-blind design. Patients performed the Continuous Performance Test (CPT), a visual vigilance test. The stimuli were the digits 0-9, with 0 a target to be responded to with a button press. EPs were recorded from 32 channels and were averaged separately for detected and undetected targets and for false positives and correctly identified nontargets (no button press). Twenty-one normal controls were also tested. Amoxapine enhanced N120 amplitude in midline parietal and right parietal cortex where selective attention effects have been found to be greatest in studies of normal controls. Both amoxapine and imipramine enhanced differences in P200 between target and nontarget stimuli in comparison to placebo, with amoxapine differences again being greatest over midline parietal locations. CPT performance was significantly better on amoxapine than placebo. 相似文献
103.
Crucial to the investigation of aircraft fatalities is the analysis of biological specimens for carbon monoxide (CO). In many cases, blood specimens are unavailable or unsuitable for analysis, and the testing of an alternate specimen for CO becomes necessary. Spleen specimens provide a rich source of red blood cells and hence can be a primary substitute for blood. To verify this, 40 paired blood and spleen specimens were analyzed for CO by using a gas chromatographic method. Ten specimens with a spleen CO saturation level (sat.) of less than 10% were associated with corresponding blood specimens with CO sat. less than 10%. Fifteen of the 18 spleen specimens with CO sat. greater than 29% were associated with blood specimens with greater than 48% sat. Results were inconclusive when the spleen CO sat. was between 10 and 29%. We concluded that spleen CO sat. can reflect blood CO sat. in certain situations, particularly when spleen CO sat. is high. 相似文献
104.
中国人不同C4基因型时血中C4浓度的定量检测 总被引:1,自引:0,他引:1
用神经氨酸酶及羧肽酶B处理血浆,依次经C4高压琼脂糖电泳、免疫固定、薄层激光扫描等步骤,并结合血浆免疫火箭电泳定量法对我国武汉地区随机人群的血浆C4总量及C4两种同种型,主要别型,单、双QO,重复座位等时的血浆C4含量进行了检测与分析。结果发现:遗传因素明显影响血浆C4水平,因而在群体中表现宽广的C4浓度范围,特别在有C4QO与C4重复基因座位时差异特别明显。这一研究提示,不同的C4基因型,循环C4含量表现明显差异。临床上检测C4含量时应该考虑患者的C4基因型别。 相似文献
105.
对我院1992年1月到1994年6月间应用KS—2A型特效癌症治疗仪治疗宫颈病变905例进行疗效分析,总的一次治愈率为97%,治疗宫颈糜烂858例,有效率100%,一次治愈率为97.4%,与冷冻治疗相比差异有显著性(P<0.001).治疗宫颈腺体囊肿34例,治愈率为84.5%.提示:与其它治疗方法相比,KS仅治疗具有治愈率高,副作用少,愈合时问短,操作简单,患者无痛苦等特点,具有推广和普及的价值. 相似文献
106.
In order to investigate the role of endothelin-1 during ischemia-reperfusion injury, 80 adult male Wistar rats were subjected to three hours of ischemia and one hour of reperfusion. Animals were evenly divided into eight groups. The rats in group 1 served as the normal control group, while the rats in group 2 received an intravenous infusion of endothelin-1 in a dosage of 0.5 ng/kg/min, group 3 in a dosage of 5 ng/kg/min, and group 4 in a dosage of 50 ng/kg/min. The rats in group 5 were infused with angiotensin II (10 ng/kg/min). The rats in group 6 received an intravenous infusion of 10,000 units of superoxide dismutase and 10,000 units of catalase. Group 7 rats were infused with endothelin-1 (50 ng/kg/min), superoxide dismutase (10,000 units), and catalase (10,000 units). Group 8 rats received an infusion of angiotensin II (10 ng/kg/min), superoxide dismutase (10,000 units) and catalase (10,000 units). The infusions were given during the reperfusion period. After one hour of reperfusion, the gastrocnemius and soleus muscles of the experimental animals were excised and assayed for ischemia-reperfusion injury by measuring triphenyltetrazolium chloride (TTC) reduction. The results showed that the limb activity of the ischemic extremity was 40.33 +/- 2.75% in group 1, 41.62 +/- 4.08% in group 2, 14.42 +/- 3.14% in group 3, 4.43 +/- 1.05% in group 4, 23.81 +/- 3.51% in group 5, 57.23 +/- 4.52% in group 6, 31.79 42- 3.63% in group 7, and 27.39 +/- 3.95% in group 8. Endothelin-1 reduced the limb activity in a dose-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
C Y Chai W C Wu S Wang C K Su Y F Lin C T Yen J S Kuo M J Wayner 《Brain research bulletin》1992,29(1):15-26
The effects of electrical stimulation and microinjection of sodium glutamate (0.5 M) in the sympathetic pressor areas of the dorsal medulla (DM), ventrolateral medulla (VLM), and parvocellular nucleus (PVC) on the knee jerk, crossed extension, and evoked potential of the L5 ventral root produced by intermittent electrical stimulation were studied in 98 adult cats anesthetized with chloralose and urethane. During electrical and glutamate stimulation of these pressor areas, in addition to the rise of systemic arterial blood pressure marked inhibition of the spinal reflex was produced, indicating presence of neuronal perikarya responsible for these actions. Mild to moderate augmentation of spinal reflexes was also observed during brain stimulation but only in a few cases. The magnitude of the somatic effects among the pressor areas of the VLM, DM, and PVC subsequent to glutamate activation was about the same. Induced spinal reflex inhibition, independent from the baroreceptor and vagal influence, remained essentially unaltered after acute midcollicular decerebration. The inhibition was also observed in cats decerebellated 8-10 days in advance. The inhibition was not affected after bilateral electrolytic- or kainic-acid-induced lesions in the paramedian reticular nucleus (PRN). On the contrary, PRN-induced spinal reflex inhibition was attenuated after bilateral lesions in the DM or VLM. Data suggest that there coexists neuronal subpopulations in the VLM, DM, and PVC that can affect both the sympathetic pressor systems and spinal reflexes. 相似文献
108.
109.
目的探讨健康教育在青光眼患者中的应用,并评价其实施效果。方法利用个体指导、健康处方、集体授课的形式,采取讲授、示范和操作的方法,对84例青光眼患者进行疾病知识、眼压监测、饮食、生活、运动等方面的健康教育。结果实施健康教育前患者知识掌握的优良率为28.6%,而实施健康教育后为80.9%,(P<0.05);实施健康教育后学会控制不良情绪、自我监测眼压、眼球按摩、正确使用降眼压眼水的人数比以前增多(P<0.05)。结论健康教育能提高青光眼患者的疾病知识水平和自我护理水平及监查依从性。 相似文献
110.
We investigated airway response to propranolol in 48 asthmatics, 17 subjects with chronic bronchitis and 19 normal subjects. The positive rate for propranolol challenge was 93.8% in asthma group, 5.9% in chronic bronchitis group while none in normal group had positive response. The challenge was highly reproducible, and it had few side-effects. This indicated that the challenge was specific and sensitive in diagnosis of asthma, it was a safe, reliable method of measuring non-specific airway responsiveness. Furthermore we also demonstrated that PC20 for propranolol did not relate to PC20 for methacholine, and that the calibre of airway did not significantly influence the airway response to propranolol. 相似文献