全文获取类型
收费全文 | 8800篇 |
免费 | 656篇 |
国内免费 | 192篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 53篇 |
妇产科学 | 181篇 |
基础医学 | 282篇 |
口腔科学 | 72篇 |
临床医学 | 1489篇 |
内科学 | 183篇 |
皮肤病学 | 19篇 |
神经病学 | 440篇 |
特种医学 | 161篇 |
外国民族医学 | 2篇 |
外科学 | 2057篇 |
综合类 | 2256篇 |
现状与发展 | 1篇 |
预防医学 | 310篇 |
眼科学 | 10篇 |
药学 | 1468篇 |
17篇 | |
中国医学 | 473篇 |
肿瘤学 | 142篇 |
出版年
2024年 | 24篇 |
2023年 | 137篇 |
2022年 | 208篇 |
2021年 | 306篇 |
2020年 | 294篇 |
2019年 | 273篇 |
2018年 | 246篇 |
2017年 | 286篇 |
2016年 | 268篇 |
2015年 | 271篇 |
2014年 | 605篇 |
2013年 | 599篇 |
2012年 | 573篇 |
2011年 | 591篇 |
2010年 | 470篇 |
2009年 | 398篇 |
2008年 | 475篇 |
2007年 | 450篇 |
2006年 | 404篇 |
2005年 | 390篇 |
2004年 | 287篇 |
2003年 | 262篇 |
2002年 | 230篇 |
2001年 | 193篇 |
2000年 | 147篇 |
1999年 | 101篇 |
1998年 | 108篇 |
1997年 | 91篇 |
1996年 | 87篇 |
1995年 | 89篇 |
1994年 | 65篇 |
1993年 | 59篇 |
1992年 | 53篇 |
1991年 | 42篇 |
1990年 | 42篇 |
1989年 | 42篇 |
1988年 | 29篇 |
1987年 | 37篇 |
1986年 | 54篇 |
1985年 | 73篇 |
1984年 | 68篇 |
1983年 | 53篇 |
1982年 | 55篇 |
1981年 | 40篇 |
1980年 | 29篇 |
1979年 | 13篇 |
1978年 | 9篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 5篇 |
排序方式: 共有9648条查询结果,搜索用时 15 毫秒
41.
V. Ventafridda E. Oliveri A. Caraceni E. Spoldi F. De Conno L. Saita C. Ripamonti 《Journal of pain and symptom management》1987,2(2):77-81
The authors report a retrospective study of 390 cancer pain patients tested with oral morphine during a four-month period. Initial pain scores were reduced to one half after one week of treatment and then maintained throughout the study period. Mean daily dosages of morphine were lower in those patients 65 years and older. No significant changes in performance in relation to therapy were noted except for an increase in hours of sleep. An accurate titration of dosage and continued control of side effects are the main requirements of this method of administration. The presence of side effects and the cause of interruption of treatment are reported. 相似文献
42.
L. S. Nuuttnen M.D. E. Wuolijoki I. T. Pentikäinen 《Acta anaesthesiologica Scandinavica》1986,30(8):620-624
The effects of a prostaglandin synthesis inhibitor (diclofenac, Voltaren) and an opiate (oxycodone, Oxanest) on postoperative pain were compared. Included in the study were 85 candidates for various operations. Patients requesting an analgesic were given either 75 mg of diclofenac or 10 mg of oxycodone as an intramuscular injection. The onset of analgesic effect occurred within 13 +/- 4 min with oxycodone and within 16 +/- 8 min with diclofenac. The analgesic effect of diclofenac was slightly weaker than that of oxycodone (on a pain scale of 1-4, 1.6/2.1 after 0.5 h and 1.5/1.8 after 1 h). The patients again asked for an analgesic after an average of 4.6 h in the oxycodone group and after an average of 6.1 h in the diclofenac group. The average number of injections required until the first postoperative morning was 2.5 in the oxycodone group and 1.8 in the diclofenac group. Side-effects: 21 patients in the oxycodone group reported a total of 39 side-effects and eight patients in the diclofenac group a total of 10 side-effects. Diclofenac is an alternative to opiates in the management of postoperative pain. It is especially useful in patients in whom opiates cause side-effects. 相似文献
43.
We have compared the performance of the Baxter disposable with the Graseby electronic patient-controlled analgesia system in 30 patients following major gynaecological surgery. Patients were allocated randomly to receive analgesia via the Baxter or Graseby device for postoperative pain relief. There were no significant differences between the two groups with regard to postoperative pain relief or sedation as measured by visual analogue scale. Requirements for antiemetic drugs and patient acceptability were similar. Mean (SEM) morphine demanded over 30 h was 35.7 (6.6) in the Graseby group and 35.1 (8.5) in the Baxter group. 相似文献
44.
老年病人上腹部手术后应用PCEA的临床效果观察 总被引:1,自引:1,他引:0
目的 观察老年人上腹部术后病人自控硬膜外镇痛 (PCEA)的疗效及对内分泌功能的影响。方法 6 3例择期行胃癌根治术的老年患者 ,ASAⅠ -Ⅱ级 ,随机分为 3组 (每组 2 1例 ) :A组术后行硬膜外镇痛 (PCEA) ;B组术后行静脉镇痛 (PCIA) ;C组术后按需肌肉注射哌替啶镇痛 ;对比术后镇痛效果并分别于麻醉前 ,切皮后 90分钟 ,术后 6 0及 1、2、3天分别抽取外周静脉血测定血糖、胰岛素、皮质醇、肾上腺素浓度。结果 A、B组镇痛效果均满意 ,C组镇痛效果欠佳 ,综合镇痛质量A组优于B组优于C组 ;3组于切皮后 90分钟血皮质醇、血糖浓度均升高 ,但A组低于C、B两组 (P <0 .0 5 ) ,术后 6 0分钟均达高峰 (P <0 0 1) ,术后 2 4至 4 8小时虽有下降 ,但仍明显高于麻醉前水平 (P <0 0 5 ) ;血胰岛素水平 ,A、B组术后 3天无明显变化 ,C组术后第 1、2天升高显著 (P <0 .0 1及P <0 .0 5 ) ;肾上腺素A、B组术后无明显升高 ,C组术后 6 0分钟明显升高 ,于术后 3天仍未恢复至术前水平。结论 老年病人上腹部术后PCIA及PCEA均能达到优良的镇痛效果 ,PCEA能有效地抑制术后机体的应激反应 ,有利于术后病人的恢复。 相似文献
45.
用小鼠热水缩尾法研究了高选择性的CCK-B受体拮抗剂PD134308的镇痛效应。PD134308在小鼠产生的镇痛有剂量依赖关系。阿片受体拮抗剂对抗其镇痛作用,表明阿片受体系统参与介导PD134308的镇痛。PD134308能加强吗啡的镇痛作用,但对α2受体激动剂可乐定的镇痛作用没有影响,表明CCK-B受体拮抗剂对阿片受体系统作用有选择性。脑啡肽酶抑制剂SCH32615加强PD134308的镇痛作用,说明PD134308可能是通过增加内源性阿片物质产生镇痛作用的。另外,PD134308还参与吗啡镇痛耐受性的形成。 相似文献
46.
通过对金锁匙口服液的药效学及毒性的研究表明:本品能明显抑制吗啡依赖性小白鼠停药后的跳跃反应,协同戊巴比妥钠催眠作用,提高小鼠热板法痛阈值,抑制醋酸引起的小鼠扭体反应,提示金锁匙口服液对吗啡类成瘾患者有一定的治疗作用,毒理研究表明;本品服用无药物依赖性、安全、无毒。 相似文献
47.
Fourteen adult patients undergoing elective major abdominal surgery were divided into two groups. One group received epidural and general anesthesia (epidural group), and 20 ml of 0.125% bupivacaine and 2 mg of morphine were administered epidurally about 30 min before the end of the operation for post-anesthetic analgesia. The other group (control group) received general anesthesia alone with nitrous oxide, oxygen and enfiurane. Flow-directed pulmonary arterial and radial arterial catheters were inserted preoperatively, and hemodynamic, respiratory, neuroendocrine and metabolic variables were measured serially. The data were compared during anesthesia and the immediate post-anesthetic recovery period. In the control group, the plasma epinephrine level in the post-anesthetic recovery period increased about four times over the anesthetic period. Oxygen consumption was increased and mixed venous oxygen saturation was decreased significantly. There was a close linear correlation between oxygen consumption (Y) and plasma epinephrine (X) level: Y = 285.7X + 90.5 (P < 0.01, r = 0.72). On the other hand, plasma epinephrine, oxygen consumption and mixed venous oxygen saturation did not change significantly in the epidural group in the post-anesthetic recovery period. There was also a close linear correlation between oxygen consumption (Y) and oxygen delivery (X): Y = 0.22X -32.0 (P < 0.01, r = 0.89). We conclude that the surgical stress and anesthetic reversal may seriously influence neuroendocrine responses and subsequently increase plasma epinephrine. Tissue oxygenation and metabolic imbalance may occur due to the rapid increase of epinephrine in the postanesthetic recovery period. Epidural analgesia at this period may play a more important role and have a more favorable effect on the tissue metabolism. 相似文献
48.
The relationship between the age and the spread of analgesia from different epidural anesthetic doses was examined by studying analgesic dose responses in cervical epidural analgesia. Two different anesthetic doses (5ml or 10ml) of 2% mepivacaine were injected into the cervical epidural space at a constant pressure (80mmHg) using an intravenous apparatus, and the spread of analgesia to pinprick was assessed. The significant correlation was found between the patients age and the number of spinal segments blocked (5ml:r = 0.8498, P < 0.01, 10ml:r = 0.5988, P < 0.01). The inverse linear relationship was found between the patients age and the segmental dose requirement (5ml:r = –0.6754, P < 0.01, 10ml:r = –0.5784, P < 0.01). Patients under 39 years of age showed a direct relationship between the dose injected and the number of spinal segments blocked, enabling prediction of the number of segments blocked with a given dose of local anesthetic. Doubling the epidural dose approximately doubled the number of spinal segments blocked. The analgesic dose-response relation in patients over 60 years of age differed from that in patients under 39 years of age and doubling the epidural dose did not double the number of spinal segments blocked. Progressively more extensive analgesia was obtained from a given dose of local anesthetic with advancing age. It was difficult to limit the extent of analgesia by injecting a smaller dose of local anaesthetic in the elderly.(Hirabayashi Y, Matsuda I, Inoue S et al.: Analgesic dose-response relation in cervical epidural block. J Anesth 2: 22–27, 1988) 相似文献
49.
目的:比较对乙酰氨基酚联合自控硬膜外镇痛的多模式术后镇痛与单纯自控硬膜外镇痛用于剖宫产产妇术后镇痛效果。方法:200名行剖宫产的产妇随机分为实验组(S组)和对照组(C组),S组产妇在术前15min静脉注射对乙酰氨基酚1g,C组产妇在术前15min静脉注射安慰剂(生理盐水)。两组产妇均采用腰硬联合麻醉方案,缝合切口时启动自控硬膜外镇痛泵。术前、术后即刻、术后1天、术后2天观察疼痛强度和血清IL-6、IL -10水平;记录新生儿出生Apgar评分、术后阿片类药物使用量及术后不良反应、产妇满意度和对母乳喂养的影响程度。结果:术后1天疼痛评分S组显著低于C组。术后即刻、术后1天S组IL-6表达水平低于C组,而该时点S组IL-10表达水平高于C组(P<0.05)。两组间不良反应、新生儿出生Apgar评分、产妇满意度和母乳喂养情况无统计学差异(P>0.05)。结论:剖宫产术前静脉注射对乙酰氨基酚联合自控硬膜外镇痛比单独应用自控硬膜外镇痛能够为产妇提供更好的术后疼痛管理。 相似文献
50.
Chronic experiments on cats showed that analgesics, in subanalgesic doses, not only exhibit an antinociceptive effect when accompanied by subthreshold stimulation of the mesencephalon, but also potentiate the analgesic action of central stimulation. Tranquilizers only facilitate the development of an analgesic effect during subthreshold mesencephalic stimulation. The possible reasons for differences in the action of these substances are discussed.Department of Pharmacology, I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR S. V. Anichkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 1, pp. 36–41, January, 1978. 相似文献