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   9480篇
  免费   881篇
  国内免费   196篇
耳鼻咽喉   28篇
儿科学   172篇
妇产科学   150篇
基础医学   521篇
口腔科学   73篇
临床医学   917篇
内科学   835篇
皮肤病学   101篇
神经病学   665篇
特种医学   146篇
外科学   397篇
综合类   1149篇
一般理论   1篇
预防医学   1161篇
眼科学   26篇
药学   3401篇
  6篇
中国医学   390篇
肿瘤学   418篇
  2024年   12篇
  2023年   233篇
  2022年   477篇
  2021年   633篇
  2020年   544篇
  2019年   477篇
  2018年   421篇
  2017年   435篇
  2016年   454篇
  2015年   445篇
  2014年   937篇
  2013年   915篇
  2012年   776篇
  2011年   794篇
  2010年   605篇
  2009年   444篇
  2008年   416篇
  2007年   346篇
  2006年   249篇
  2005年   211篇
  2004年   126篇
  2003年   98篇
  2002年   69篇
  2001年   59篇
  2000年   44篇
  1999年   47篇
  1998年   37篇
  1997年   31篇
  1996年   28篇
  1995年   34篇
  1994年   24篇
  1993年   23篇
  1992年   15篇
  1991年   9篇
  1990年   15篇
  1989年   10篇
  1988年   7篇
  1987年   5篇
  1986年   16篇
  1985年   9篇
  1984年   12篇
  1983年   2篇
  1982年   3篇
  1981年   2篇
  1980年   2篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
  1970年   1篇
  1968年   1篇
排序方式: 共有10000条查询结果,搜索用时 312 毫秒
31.
Non-ionic contrast media (CM) are proven to be significantly safer than the high osmolar ionic contrast media (HOCM). Nevertheless deaths are reported after administration of non-ionic agents. The aim of the study was to investigate the rate of adverse reactions to non-ionic CM with special regard to high-risk patients and the effects of premedication with H1-and H2-receptor antagonists.In a prospective study conducted over about 2 years 12 995 examinations with intravenous or intra-arterial non-ionic CM were evaluated. Premedication with H1-and H2-antagonists was used in 1276 high-risk patients with known adverse reaction to CM, history of allergy or severe cardiac or pulmonary disease. 229 patients received no premedication inspite of known risk factors. In total, there were 143 (1.10%) adverse reactions (mild in 0.58%, moderate in 0.41% and severe in 0.05%). In high-risk patients there were adverse reactions in 4.37% without and in 1.57% with premedication. There were no severe adverse reactions in the high-risk patients after premedication. The age of the patient, CM dosage and CM concentration were not shown to be risk factors in the present study. In conclusion, the additional premedication with H1- and H2-antagonists could be an effective agent to reduce the risk of mild and moderate adverse reactions and to avoid severe adverse reactions in high-risk patients. Correspondence to: U. Fink  相似文献   
32.
This study investigates functional disability among some of the nation's most vulnerable older adults: rural Medicaid recipients. Data were provided by 221 older adults (mean age = 75.9 years; 82% women) who were receiving community-based long-term care services through Medicaid. Participants self-reported functional ability involving the completion of six basic activities of daily living (BADLs), three cognitive instrumental activities of daily living (IADLS), and four physical IADLs. Self-reports of depressed affect and the number of physical health conditions were also obtained. Path analysis was used to examine all of the associations among age, gender, number of chronic health conditions, depressed affect and functional disability. The tested model was significant [chi2 (DF = 3, n = 221) = 5.052, p = 0.168; TLI = 0.945; CFI = 0.992; RMSEA = 0.056] and explained 45.1% of the variance in BADL disability. Depressed affect significantly predicted disability in cognitive IADLs and physical IADLs, which predicted disability in BADLs. Age and gender had indirect effects on BADL, through their association with cognitive IADLs and physical IADLs. The number of chronic health conditions exerted both indirect and direct effects on BADL disability. Results are discussed within the context of the growing literature that suggests the importance of psychological variables as predictors of functional disability. Moreover, we discuss whether community-based long-term care is appropriate for older adults with high levels of functional disability.  相似文献   
33.
目的探讨欧乃影在临床应用中不良反应的发生和预防措施。方法观察2003年10月至2006年7月所作1000例增强扫描者静脉注射欧乃影0.2mL/kg(其量浓度(c)为0.5mol/L)后,不良反应发生的情况。结果1000例患者中,出现不良反应6例,其中,非过敏反应3例,轻度过敏反应3例,无中度及重度过敏反应。结论欧乃影在磁共振增强扫描中不良反应发生率低,临床应用安全。  相似文献   
34.
Summary All the clinical, laboratory and electrocardiographic adverse events detected during 24 Phase I studies in the same unit over a 5 y period are reported here. 430 healthy male volunteers were involved, corresponding to 5488 days of follow-up.The overall incidence of adverse events was 13.5%, with a significant difference between active drug (15.3%) and placebo (7.4%) treatments. There were 69 distinct types of adverse events. Headache was the most frequent symptom (2%). There were severe adverse events in 20 cases (0.36%), with an incidence of 20/430 per subject (4.6%). There were no deaths or life-threatening events.Although the main objective of Phase I studies is to determine the maximum dose tolerated, cause-effect relationships with adverse events are hard to establish, because of the frequency of adverse events with placebo, and because of the limited number of subjects included such studies.  相似文献   
35.
We describe how adverse drug reactions (ADRs) can play an important role in pharmaceutical research and drug development. Not only do ADRs represent the risks and drawbacks associated with drugs but they can also be related to other knowledge available in pharmaceutical and medical research. We offer a model that can be used to systematically map the pathways through which ADRs can lead to innovative research. These pathways include chemical, therapeutic or pathophysiological steps that can be taken to arrive at new knowledge based on ADRs. We used the development of angiotensin-converting enzyme inhibitors, especially captopril, as a case study. The similarity between the ADR profiles of captopril and penicillamine was a starting point for further innovation. Historical analysis shows that in several instances research in the field of angiotensin-converting enzyme inhibitors has been triggered by ADRs. The model presented here might be applicable to other areas of innovative drug research.  相似文献   
36.
A prospective survey was performed in 17 nuclear medicine departments during 1996 in an attempt to provide reliable data on the prevalence of adverse reactions to radiopharmaceuticals. All adverse events following radiopharmaceutical administration were recorded, irrespective of the severity or likelihood of causality, and subsequently analysed using an algorithm developed by Silberstein et al., designed to establish a cause-effect relationship. A prevalence of 11 events per 105 administrations was obtained (95% confidence limits 3.3–19.2). No serious of life-threatening events were reported. This rate is slightly higher than that obtained in a larger scale study in the United States (2.3 events per 105 administrations, 95% confidence limits 1.2–3.4). The difference may be due to the decision to include or exclude vasovagal events from the analysis, the way in which the algorithm was used and the comparative size and time scale of the two studies. The prevalence of adverse reactions is approximately 1000-fold than less that occurring with iodinated contrast media and drugs.  相似文献   
37.
In the cerebellar type of multiple system atrophy (MSA-C), the burden of pathological changes involves the cerebellum and its associated brainstem structures in the basis pontis and the inferior olivary nucleus, and as a result, the clinical phenotype is dominated early on by the cerebellar dysfunction. We report our clinical and post mortem findings in a patient with MSA-C who exhibited pathological laughter in the absence of any congruent changes of mood. A review of the clinical notes of 27 other patients with MSA-C revealed a problem with pathological laughter, or crying, or both in 9 more patients. Our finding of about 36% occurrence suggests that the problem of dysregulation of emotional expression is more prevalent in MSA-C than the paucity of reports in the literature suggests. Our findings are consistent with the view that the cerebellum and its interconnected structures may be involved in the regulation of emotional expression.  相似文献   
38.
目的 探讨基层药品不良反应监测网络建设模式,为药品不良反应监测组织体系的完善提供参考.方法 通过建立山东省基层药品不良反应监测网络的实践,研究、分析基层药品不良反应监测网络的建设模式.结果 建立了高效、快捷的三级药品不良反应监测网络,促进了山东省药品不良反应监测工作的全面发展.结论 建立健全机构设施完备、职责明确、运作规范的基层监测网络,有利于完善我国药品不良反应监测组织体系,推动药品不良反应监测工作的深入开展.  相似文献   
39.
Summary:  Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV.  相似文献   
40.
平阳霉素治疗脉管性疾病不良反应105例临床分析   总被引:2,自引:0,他引:2  
目的:总结平阳霉素(PYM)治疗口面部等脉管性疾病的不良反应,为临床预防或减少其不良反应提供依据。方法:收集1991年6月至2004年6月,用PYM治疗各种脉管性疾病1 142例,其中有不良反应的105例,男49例,女56例,年龄3个月至30岁的病人,作回顾性统计分析。结果:用PYM治疗脉管性疾病的病例中,有不良反应105例,不良反应率为9.19%(105/1 142),其中食欲不振45例占3.94%,发热42例占3.68%,皮疹17例占1.49%,休克1例占0.08%。结论:食欲不振与用PYM相对剂量较大有关,预防的方法是适当减少PYM的剂量。注射PYM前先肌注DXM不仅可预防或减少PYM的发热反应,还可防治PYM的过敏反应。用PYM治疗脉管性疾病时,一旦出现皮疹等过敏反应,就不能再用此药冶疗。  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