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   752篇
  免费   78篇
  国内免费   8篇
耳鼻咽喉   5篇
儿科学   66篇
妇产科学   6篇
基础医学   124篇
口腔科学   30篇
临床医学   72篇
内科学   139篇
皮肤病学   19篇
神经病学   23篇
特种医学   128篇
外科学   93篇
综合类   42篇
预防医学   25篇
眼科学   29篇
药学   12篇
肿瘤学   25篇
  2023年   1篇
  2022年   3篇
  2021年   4篇
  2020年   7篇
  2019年   7篇
  2018年   21篇
  2017年   7篇
  2016年   21篇
  2015年   22篇
  2014年   26篇
  2013年   44篇
  2012年   19篇
  2011年   13篇
  2010年   45篇
  2009年   47篇
  2008年   16篇
  2007年   28篇
  2006年   15篇
  2005年   21篇
  2004年   9篇
  2003年   12篇
  2002年   11篇
  2001年   9篇
  2000年   9篇
  1999年   11篇
  1998年   41篇
  1997年   43篇
  1996年   43篇
  1995年   36篇
  1994年   23篇
  1993年   29篇
  1992年   5篇
  1991年   9篇
  1990年   10篇
  1989年   25篇
  1988年   23篇
  1987年   13篇
  1986年   18篇
  1985年   18篇
  1984年   9篇
  1983年   12篇
  1982年   5篇
  1981年   13篇
  1980年   7篇
  1979年   4篇
  1978年   4篇
  1977年   8篇
  1976年   9篇
  1975年   2篇
  1884年   1篇
排序方式: 共有838条查询结果,搜索用时 15 毫秒
41.
42.
由于治疗方法的进步,近80%的儿童和青少年癌症患者能够长期生存。在美国,约有270000例儿童癌症的幸存者,即每640名20至39岁成年人中就有一名幸存者。大量的幸存者有利于儿童癌症治疗后长期健康结果的研究。现在可以明确的是,化疗和放疗所致的儿童各器官系统损害在临床上可能潜伏多年。为了全面了解治疗儿童癌症而继发的健康问题,重要的是衡量三项长期结果:健康状况、死亡率和患病率。这三项中,关于前两项已有相当好的研究报道。在一项对20227例癌症5年生存者的回顾性分析中,Mertens等发现以下原因导致的超额死亡率具有统计学意义:继发癌症(…  相似文献   
43.
目的探讨高脂血症性急性胰腺炎(HAP)和非高脂血症性急性胰腺炎的特点及临床救治效果。方法回顾分析我院在2013年1月至2013年12月收治的99例急性胰腺炎的临床资料,根据患者有无高脂血症将其分为HAP组(高脂血症患者)和对照组(无高脂血症的AP患者);患者均接受标准化临床治疗,比较2组患者病情、血浆生化指标、治疗转归、住院时间与费用、复发等情况。结果 HAP组重度胰腺炎比例(13.6%)明显高于对照组(7.8%),HAP组血糖和尿酸均显著高于对照组,其中HAP组血糖平均值达到对照组的171%,而HAP组的血淀粉酶却仅为对照组的44.5%;HAP组1年内的复发率(13.6%)显著高对于照组(2.6%),P0.01差异有统计学意义。结论高血脂对急性胰腺炎的病情、表现和治疗结果均有明显影响,应引起高度重视。  相似文献   
44.
We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63 467 women aged ≥ 45 years, of whom 12 613 (19.9%) reported any history of migraine and 9195 had active migraine. Compared with women without migraine and a BMI < 23 kg/m2, women with a BMI ≥ 35 kg/m2 had adjusted odds ratios (ORs) (95% confidence intervals) of 1.03 (0.95, 1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of ≥ 35 kg/m2 had increased risk for low and high migraine frequency, with the highest estimate for women who reported daily migraine. Compared with women with the lowest associated risk (migraine frequency < 6 times/year; BMI between 27.0 and 29.9 kg/m2), women with a BMI ≥ 35 kg/m2 had an OR of daily migraine of 3.11 (1.12, 8.67). Among the women with active migraine, a BMI ≥ 35 kg/m2 was associated with increased risk of phonophobia and photophobia and decreased risk of a unilateral pain characteristic and migraine aura. Our data confirm previous findings that the association between BMI with migraine is limited to migraine frequency and specific migraine features.  相似文献   
45.
46.
47.
Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine.  相似文献   
48.
A cross sectional study assessed the bone mineral density (BMD) of 20 young adult patients who received a renal transplantation in childhood. The BMD of the lumbar spine, mainly trabecular bone, and of the total body, mainly cortical bone, were measured and expressed as an SD score. Fourteen patients (70%) had a BMD SD score of the lumbar spine below -1, of whom six patients were below -2. Fifteen patients (75%) had a BMD SD score of the total body below -1, of whom seven patients were below -2, Both trabecular and cortical bone appeared to be involved in the osteopenic process. The cumulative dose of prednisone was inversely correlated to both lumbar spine and total body BMD SD score. In a multiple regression analysis the cumulative dose of prednisone appeared to be the only factor with a significant effect on BMD SD score. Most young adult patients who had received a renal transplantation in childhood had moderate to severe osteopenia. Corticosteroid treatment played a major part in the development of osteopenia in these patients.  相似文献   
49.
Obesity in children may cause overt clinical disease in childhood. The complex endocrine and metabolic changes of obesity and insulin resistance in adolescents result in hyperinsulinemia, dyslipidemia, hypertension, steatohepatitis, glucose intolerance, type 2 diabetes, acanthosis nigricans and ovarian hyperandrogenemia, commonly known as polycystic ovarian syndrome (PCOS). Type 2 diabetes and PCOS in adolescents are new endocrine diseases in this age group that require unique approaches to diagnosis and treatment. The direct correlation between duration of disease and control of the disease, and subsequent long term complications of these two diseases, predict serious morbidity in young adult life for the affected adolescents. Pediatricians have an important role in the prevention, diagnosis and treatment of obesity, insulin resistance syndrome, type 2 diabetes and PCOS.  相似文献   
50.
The relationship between homovanillic acid (HVA), vanillylmandelic acid (VMA), and creatinine in the urine of 6 month old babies has been studied and reference ranges in the form of centiles constructed for HVA and VMA against creatinine. Over 10,000 urine samples were collected from babies in four health districts in the north of England. HVA and VMA concentration, either independently or when divided by creatinine concentration, were dependent upon the absolute concentration of creatinine in the sample. After adjustment for creatinine significant differences in the mean concentration of HVA were found between sexes. No such differences were found for VMA. HVA and VMA were also found to be age dependent. Centiles were constructed using a procedure which makes no distributional assumptions about the data. The net effect of utilising these centiles was to increase the predictive value of a positive screening test from 20% to 40% without any increase in the false negative rate.  相似文献   
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