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   1085篇
  免费   41篇
  国内免费   10篇
耳鼻咽喉   15篇
儿科学   111篇
妇产科学   73篇
基础医学   90篇
口腔科学   46篇
临床医学   101篇
内科学   199篇
皮肤病学   25篇
神经病学   105篇
特种医学   22篇
外科学   139篇
综合类   20篇
预防医学   45篇
眼科学   24篇
药学   30篇
中国医学   2篇
肿瘤学   89篇
  2023年   8篇
  2022年   18篇
  2021年   32篇
  2020年   16篇
  2019年   23篇
  2018年   41篇
  2017年   42篇
  2016年   37篇
  2015年   33篇
  2014年   46篇
  2013年   57篇
  2012年   72篇
  2011年   76篇
  2010年   56篇
  2009年   43篇
  2008年   79篇
  2007年   88篇
  2006年   82篇
  2005年   70篇
  2004年   59篇
  2003年   43篇
  2002年   50篇
  2001年   13篇
  2000年   2篇
  1999年   4篇
  1998年   3篇
  1997年   7篇
  1996年   8篇
  1995年   9篇
  1994年   2篇
  1993年   3篇
  1992年   2篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   2篇
  1985年   1篇
  1981年   2篇
  1980年   1篇
  1968年   1篇
排序方式: 共有1136条查询结果,搜索用时 93 毫秒
1.
2.
3.
Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error.  相似文献   
4.
5.
Casonis skin test and indirect haemagglutination test (IHA) are still used in Turkey. The preoperative IHA test or Casonis skin test results of 120 patients with surgically confirmed hydatidosis were retrospectively studied during 1997–2004. At the same period, 306 patients with non-hydatid disease had serologic results for echinococcosis. The sensitivity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 70, 62, and 56%, respectively. Casonis skin test components had higher sensitivity than IHA (P<0.01). The specificity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 87, 85, and 84%, respectively. Cystic lesions in non-hydatid patients were localised commonly in the lungs. The occurrence of hydatid disease for pulmonary, hepatic, and renal cysts was 19, 54, and 5%, respectively. An immediate skin reaction to crude hydatid antigens is more useful than IHA.  相似文献   
6.

Background

Hereditary angioedema (HAE) attacks can be provoked with psychological factors. The aim of this study was to assess the effects of anxiety, depression and stress related to COVID-19 pandemic on disease activity of HAE patients during the quarantine period (QP) and the return to normal period (RTNP).

Methods

This study was conducted between March 2020 and September 2020 in four allergy centres. Demographic, clinical features and mental health status were evaluated in QP (from March to the beginning of June) and RTNP (from June to the beginning of September) applied by the government. The 10-point visual analogue scale (VAS10) was used to define the severity of HAE attacks. Depression, Anxiety and Stress Scales-21 (DASS-21) and Fear of COVID-19 (FC-19) scale were performed to assess mental health status.

Results

139 HAE patients were included in the study. In QP, median attack numbers and median VAS10 scores were 5 (min-max: 0–45) and 6 (min-max: 0–10), respectively. HAE attack numbers, DASS-21 stress, anxiety, depression and total DASS-21 scores, and FC-19 scores were higher in QP than RTNP (p = 0.001, p < 0.001, p = 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). However, there was no difference in attack severity scores between the two periods (p > 0.05).

Conclusions

This study revealed that the restriction measures during COVID-19 outbreak cause an increase in the number of HAE attacks in relation to anxiety, depression, stress and fear of COVID-19 pandemic. Therefore, it is important to provide psychological support to HAE patients during the pandemic.
  相似文献   
7.
8.
Infantile spasm is an age-specific epileptic encephalopathy. Long-term intellectual outcome of affected infants remains poor. The pathogenesis of infantile spasms, as well as the development of mental retardation, remains unclear. Increased excitatory amino acid neurotransmission may play a role in neuronal dysfunction and epilepsy. To study the significance of cerebrospinal fluid excitatory amino acids in infantile spasms, we determined glutamate and aspartate concentrations in cerebrospinal fluid of 13 patients with infantile spasms and 13 controls. The aspartate level in cerebrospinal fluid of the patients with infantile spasms (968 ± 416 nmol/1) was higher than the control group (426 ± 272nmol/l). No difference in the mean glutamate levels was found between the patients (966 ± 395 nmol/1) and the controls (1135 ± 594 nmol/1). The elevated aspartate levels in cerebrospinal fluid of the patients with infantile spasms might be secondary to change in metabolism of aspartate. Aspartate is an excitatory and neurotoxic neurotransmitter, which might have a role in triggering the spasms and the development of neuronal dysfunctions in the patients with infantile spasms.  相似文献   
9.
10.
Suffering comes in many ways for patients confronting cancer. One of these is an unspecifiable fear about death, which is an existential issue. The aim of this study was to investigate the relationship between death anxiety and its correlates in cancer patients. Seventy cancer patients were assessed using SCID-I, Templer's Death Anxiety Scale, the Hospital Anxiety (A) and Depression (D) Scale, the Distress Thermometer, the Visual Analogue Scale for pain (VAS), the Global Assessment of Functioning, and Glock and Stark's Dimensions of Religious Commitment scales, and these assessments were compared between cancer patients with and without death anxiety. Multiple regression analysis was conducted after correlation analysis between death anxiety and sociodemographic and clinical variables. Axis I psychiatric diagnosis, pain scores, and negative believes about what will happen after death were found to be higher in patients having death anxiety than patients not having death anxiety. Also life expectancy was perceived as shortened in patients with death anxiety. Death anxiety was associated with anxiety, depressive symptoms, and beliefs about what will happen after death. In conclusion, death anxiety could not be regarded as a natural consequence of having cancer; it is associated with the unresolved psychological and physical distress.  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