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   18800篇
  免费   941篇
  国内免费   133篇
耳鼻咽喉   162篇
儿科学   303篇
妇产科学   233篇
基础医学   2165篇
口腔科学   296篇
临床医学   1292篇
内科学   5071篇
皮肤病学   320篇
神经病学   1098篇
特种医学   712篇
外科学   3909篇
综合类   116篇
预防医学   599篇
眼科学   234篇
药学   1091篇
  4篇
中国医学   50篇
肿瘤学   2219篇
  2023年   184篇
  2022年   293篇
  2021年   500篇
  2020年   287篇
  2019年   356篇
  2018年   468篇
  2017年   330篇
  2016年   453篇
  2015年   474篇
  2014年   577篇
  2013年   635篇
  2012年   1131篇
  2011年   1209篇
  2010年   672篇
  2009年   533篇
  2008年   1024篇
  2007年   1114篇
  2006年   1024篇
  2005年   1053篇
  2004年   989篇
  2003年   864篇
  2002年   906篇
  2001年   430篇
  2000年   418篇
  1999年   400篇
  1998年   225篇
  1997年   187篇
  1996年   161篇
  1995年   136篇
  1994年   115篇
  1993年   127篇
  1992年   240篇
  1991年   203篇
  1990年   193篇
  1989年   187篇
  1988年   178篇
  1987年   178篇
  1986年   156篇
  1985年   169篇
  1984年   126篇
  1983年   111篇
  1982年   50篇
  1980年   43篇
  1979年   82篇
  1978年   61篇
  1977年   53篇
  1974年   49篇
  1973年   48篇
  1971年   48篇
  1968年   45篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
The effectiveness of Tc-99m bleomycin (BLM) and Tc(V)-99m DMSA are compared with that of Ga-67 citrate, which is currently the most widely used agent. In four patients with lipomatous tumors, the clinical significance of tumor imaging with each of these three agents is discussed and compared. Results indicate that both Tc-99m BLM and Tc(V)-99m DMSA are superior in detecting the extension or localization of liposarcomas.  相似文献   
22.
23.
24.
To clarify the role of serotonin in cerebral ischemia, we examined the effects of selective serotonin reuptake inhibitors, citalopram and clomipramine, on ischemic neuronal damage in the gerbil. Pretreatment with citalopram (40 mg/kg i.p.) and clomipramine (20 mg/kg i.p.) protected against neuronal destruction of hippocampal CA1 pyramidal cells following 5 min of forebrain ischemia. Furthermore, microdialysis assays showed that a striking increase in extracellular excitatory amino acid levels during ischemia was significantly inhibited by pretreatment with citalopram and clomipramine. However, citalopram (40 mg/kg i.p.) did not alter the extracellular amino acid concentrations in normal gerbils. Thus, serotonin reuptake inhibitors have a protective effect against ischemic neuronal damage. Furthermore, the present result suggests that the protective effect is mediated through prevention of the accumulation of extracellular excitatory amino acids during and after ischemia.  相似文献   
25.
Late Effects of Childhood Acute Leukemia and Its Treatment   总被引:1,自引:0,他引:1  
Late effects of childhood acute leukemia and its treatment were studied in 766 patients (684 ALL, 73 ANLL, and 9 others) in Japan who had remained in remission for more than 1 year after their first complete remission. Delayed adverse sequelae involve a wide variety of organs and their functions. Short stature was present in 2.61%, obesity in 3.79%, abnormalities of growth hormone secretion in 1.5%, delayed secondary sex characteristics in 1.5% of males and 0.6% of females, motor disturbances in 1.17%, sensory disturbances in 0.91%, intellectual and learning disabilities in 2.48%, abnormal findings in routine neurologic examinations in 1.31%, EEG abnormalities in 4.30%, brain CT abnormalities in 5.09% and cardiac dysfunction in 1.07%. Various other disorders were seen in 20 patients. Many of these delayed adverse sequelae are caused by or related to central nervous system prophylaxis and systemic combination chemotherapy. The results suggest that it is needed to improve therapeutic methods through the stratification of patients by risk factors and detailed analysis of prognostic factors. Moreover it is important to render medical and psychosocial support to long-term survivors of childhood leukemia through interactions between the patient, parents and medical staff.  相似文献   
26.
27.
28.
Hypertension after extracorporeal shock wave lithotripsy (ESWL) has been a controversial subject. Changes in blood pressure were studied in 262 patients (mean age 47.8 years) 18.6 months after ESWL. According to World Health Organization criteria the number of patients who showed a decrease exceeded those who showed an increase in blood pressure. The patients who have been on antihypertensive therapy showed a significantly greater decrease in blood pressure than those without medication. Of 192 normotensive patients diastolic pressure increased 1.2 mm. Hg and 2 (1.0%) had hypertension 18.4 months after ESWL. Annualized increase in diastolic pressure and new onset of hypertension were calculated to be 0.78 mm. Hg and 0.65%, respectively. Significant elevation of diastolic pressure was noted in the patients who received a larger number of shock waves. Blood pressure should be carefully followed after ESWL especially in patients who have been treated by a greater number of shock waves.  相似文献   
29.
OBJECTIVE: There might be a difference between non-working and working women in their perception of rights and privileges which may influence their contraceptive behavior. The purpose of this study was to examine contraceptive behavior among non-working and working women in Bangladesh determining associated factors. METHOD: Analysis was based on data from the 1999-2000 Bangladesh Demographic and Health Survey which employs nationally representative sample. RESULTS: The prevalence of current contraceptive use (any method) was 58.2% among non-working women and 65.5% among working women. Both rates are still low for the country. Some factors, such as discussed family planning with husband, husband approves family planning, desire for more children, and husband lives together, were influential determinants of lower contraceptive prevalence among the non-working women. CONCLUSION: The results indicate a necessity for social activities promoting husband-wife communication and women's participation in employment to enhance the use of contraceptives among Bangladeshi women, especially non-working women.  相似文献   
30.
Amygdaloid-kindled rats received intravenous human copper-zinc superoxide dismutase (CuZn-SOD) either in free form or entrapped within liposomes (SOD-L), at 5, 10 or 20 mg/kg. The animals were stimulated at the generalized seizure-triggering threshold 5 min, 2 h and then every 24 h after the drug was given, until 5 consecutive stage 5 seizures were induced. Free CuZn-SOD had little or no effect. However, SOD-L, particularly at 10 mg/kg, had a prolonged anticonvulsant effect, although there was great individual variation in the onset and duration of seizure suppression. This effect of SOD-L may be due to the ability of liposomes to act as a depot for the sustained release of drugs.  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