首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   26733篇
  免费   1301篇
  国内免费   1527篇
耳鼻咽喉   259篇
儿科学   508篇
妇产科学   415篇
基础医学   3498篇
口腔科学   317篇
临床医学   2350篇
内科学   4291篇
皮肤病学   395篇
神经病学   1322篇
特种医学   881篇
外国民族医学   23篇
外科学   2618篇
综合类   3730篇
现状与发展   29篇
一般理论   6篇
预防医学   1657篇
眼科学   1027篇
药学   2524篇
  10篇
中国医学   1116篇
肿瘤学   2585篇
  2024年   123篇
  2023年   435篇
  2022年   350篇
  2021年   315篇
  2020年   235篇
  2019年   200篇
  2018年   216篇
  2017年   155篇
  2016年   195篇
  2015年   203篇
  2014年   474篇
  2013年   383篇
  2012年   3560篇
  2011年   3831篇
  2010年   875篇
  2009年   538篇
  2008年   2471篇
  2007年   2329篇
  2006年   2124篇
  2005年   1861篇
  2004年   1702篇
  2003年   1417篇
  2002年   1239篇
  2001年   797篇
  2000年   1030篇
  1999年   484篇
  1998年   286篇
  1997年   219篇
  1996年   164篇
  1995年   152篇
  1994年   147篇
  1993年   119篇
  1992年   113篇
  1991年   109篇
  1990年   90篇
  1989年   103篇
  1988年   73篇
  1987年   72篇
  1986年   54篇
  1985年   55篇
  1984年   26篇
  1983年   34篇
  1982年   32篇
  1981年   25篇
  1980年   23篇
  1979年   12篇
  1964年   10篇
  1962年   10篇
  1959年   9篇
  1957年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
目的:探讨乳腺癌患者的保乳术中采用放射状切口及弧行切口的效果差异。方法:选取2015年2月-2017年2月在笔者医院接受保乳术治疗的乳腺癌患者106例,通过随机数字表法分成对照组和观察组,每组53例。对照组接受放射状切口保乳术治疗,观察组接受弧行切口保乳术治疗。比较两组患者手术前后的生活质量评分以及术后美容效果。结果:治疗前两组患者的躯体健康、躯体角色功能、躯体疼痛、社会功能、情绪角色功能、心理健康、精力、总体健康以及总分等各项目评分比较,差异均无统计学意义(P0.05)。治疗后观察组的生活质量各项目评分均显著高于对照组,差异有统计学意义(P0.05)。观察组美容优良率为94.34%高于对照组的81.13%,差异有统计学意义(P0.05)。结论:临床上在针对乳腺癌患者实施保乳术中,行弧行切口效果良好,术后患者的生活质量显著改善,且美容效果良好,具有较高的临床价值。  相似文献   
4.
INTRODUCTION Alzheimer disease can be classified into familial Alzheimer disease (FAD) and sporadic Alzheimer disease (SAD)[1]. Among FAD, ear- ly-onset FAD(EOFAD) is a familialform in which the onset ofsymptoms occurs before the age of 60 to 65 years, an…  相似文献   
5.
Objective: To observe the clinical effect of Neiyifang (NYF) in treating endometriosis and to explore its therapeutic mechanism through observing its influence on plasma β-endorphin (β-EP) in different menstrual stages and levels of prostaglandins (PGs) in menstruation.Methods:NYF was administered to 104 patients with endometriosis one dose daily with 3 successive menstrual cycles as one therapeutic course. Peripheral blood β-EP level in follicular, luteal and menstrual stages, as well as PGF, PGE2, thromboxane B2 and 6-keto-PGFl α levels in menstrual stage were detected by RIA, and controlled with those in 15 healthy persons.Results: (1) The total effective rate of NYF was 81.3% and it showed significant effect in improving patients’ clinical symptoms and physical signs; (2) In menstrual stage, the levels of β-EP, 6-keto-PGFα/ TXB2 were lower(P <0.05) and levels of PGF, PGE2, TXB2 and 6-keto-PGF were higher (P< 0. 05) in patients than those in control, and the higher the level of PGE2, the severer the menalgia, (3) NYF could increase levels of β-EP, 6-keto-PGF, and reduce levels of PGF, PGE in menstrual stage of patients (all P<0.05).Conclusion: (1) NYF has good clinical effect in treating endometriosis; (2) Patients’ symptom of menalgia is closely related with the excessive high levels of PGF and PGE2, PGI2/TXA2 ratio disturbance, and excessive low level of β-EP; (3) NYF could significantly decrease the PGE2, PGF levels, increase the 6-keto-PGF/TXB2 ratio and the level of β-EP, so as to alleviate the menalgia in patients with endometriosis. This item was supported by National Funds of Natural Sciences(No. 30070942)  相似文献   
6.
外科术后病人深静脉血栓形成的预防及护理   总被引:2,自引:0,他引:2  
  相似文献   
7.
支架型人工血管植入术治疗全主动脉夹层和狭窄一例   总被引:5,自引:0,他引:5  
1 病例摘要患者 ,女性 ,46岁 ,2 0 0 1年 1月 9日在排便用力时突感胸部剧烈疼痛伴呼吸困难急诊入院。查体 :体温 3 7.2℃ ,心率 1 1 6次 / min,呼吸2 5次 / min,血压 1 71 / 99mm Hg。呼吸窘迫状态 ,唇稍紫 ,左上腹轻压痛。 EKG:S-T段抬高 ,急性心肌缺血表现。彩色多普勒示 :主动脉夹层动脉瘤 ,自升主动脉一直撕裂到双侧髂总动脉。立即予“硝酸甘油、曲马多”止痛、降压。入院第3天行磁共振血管造影诊断为 :马凡氏综合症 ,De Bakey 型主动脉夹层。入院第 1 0天行主动脉血管造影发现 :升降主动脉被假腔压迫而致严重狭窄 ,在升主动脉远侧…  相似文献   
8.
前言     
生物进化已有数十亿年历史,在5~6亿年前的寒武(Cambrian)纪爆发了基因突变现象。当时大气中氧浓度比现在低,不足百分之几,但其后约2亿年的光景,地球才形成了目前的氧环境。但是,包括人在内的动物体内,至今却仍保有着类似寒武纪时的低氧环境部位,尤其是消化道内就是寒武纪以前的环境。这样的低氧环境一旦在脑和心脏等重要器官内发生,就会诱发严重的缺血、再循环障碍等。这时,能量代谢和白细胞的性状将发生剧变,脂质、蛋白质、基因等由于受到氧化应激的伤害而引起各种各样的疾病。目前,活性氧的研究盛行,再加上大众传媒报道,出现了“活性氧是…  相似文献   
9.
Changes in T .lymphocyte subsets after severe traumatic brain inJury   总被引:2,自引:0,他引:2  
BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14- 15 points), including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS: (1) The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. (2) The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. (1) Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77 - 3.26, P 〈 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06 - 2.24, P 〈 0.05), and generally recovered to the normal levels at 14 days (P 〉 0.05). (2) Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, x2=37.29, P 〈 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号