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   844篇
  免费   36篇
  国内免费   5篇
儿科学   27篇
妇产科学   8篇
基础医学   73篇
口腔科学   23篇
临床医学   65篇
内科学   134篇
皮肤病学   18篇
神经病学   15篇
特种医学   193篇
外科学   111篇
综合类   39篇
预防医学   30篇
眼科学   23篇
药学   73篇
中国医学   13篇
肿瘤学   40篇
  2023年   3篇
  2022年   5篇
  2021年   23篇
  2020年   11篇
  2019年   9篇
  2018年   14篇
  2017年   9篇
  2016年   15篇
  2015年   17篇
  2014年   22篇
  2013年   30篇
  2012年   43篇
  2011年   35篇
  2010年   37篇
  2009年   22篇
  2008年   41篇
  2007年   40篇
  2006年   26篇
  2005年   39篇
  2004年   17篇
  2003年   23篇
  2002年   21篇
  2001年   14篇
  2000年   17篇
  1999年   12篇
  1998年   21篇
  1997年   40篇
  1996年   28篇
  1995年   21篇
  1994年   15篇
  1993年   14篇
  1992年   9篇
  1991年   7篇
  1990年   11篇
  1989年   9篇
  1988年   15篇
  1987年   22篇
  1986年   21篇
  1985年   14篇
  1984年   10篇
  1983年   6篇
  1982年   11篇
  1981年   14篇
  1980年   13篇
  1979年   4篇
  1978年   7篇
  1977年   7篇
  1976年   8篇
  1975年   5篇
  1971年   2篇
排序方式: 共有885条查询结果,搜索用时 390 毫秒
81.
82.
Monitoring for undertransfusion   总被引:1,自引:0,他引:1  
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components.  相似文献   
83.
We investigated the efficacy, safety and tolerability compared with placebo of a second dose of oral sumatriptan 100 mg in 1349 general practice patients who had already treated a moderate or severe migraine headache with 100 mg sumatriptan 4 h earlier. Headache was relieved by the first sumatriptan dose in about 70% of patients, but the second dose did not produce significantly more relief than placebo, either in nonresponders or in the group as a whole, nor did it reduce other symptoms (photophobia, nausea, vomiting, etc,) at 8 h, or influence the incidence of headache recurrence. The drug was well-tolerated, and a further single dose was effective in treating recurrence after initial relief. A single 100 mg dose of sumatriptan is an effective acute treatment for migraine. A second dose should be reserved for treating headache recurrence.   相似文献   
84.
85.
Gamma-aminobutyric acid (GABA) and glutamate are implicated in numerous neuropsychiatric and substance abuse conditions, but their spectral overlap with other resonances makes them a challenge to quantify in humans. Gabapentin, marketed for the treatment of seizures and neuropathic pain, has been shown to increase in vivo GABA concentration in the brain of both rodents and humans. Gabapentin effects on glutamate are not known. We conducted a gabapentin (900 mg) challenge in healthy human subjects to confirm and explore its effects on GABA and glutamate concentrations, respectively, and to test the ability of single voxel localized proton magnetic resonance spectroscopy (1H-MRS) to reliably measure GABA and glutamate in the visual cortex at the ultra-high magnetic field of 7 Tesla. Reproducibility of GABA and glutamate measurements was determined in a comparison group without drug twice within day and 2 weeks apart. Although GABA concentration changes were small both within day (average 5.6%) and between day (average 4.8%), gabapentin administration was associated with an average increase in GABA concentration of 55.7% (6.9–91.0%). Importantly, drug-induced change in GABA levels was inversely correlated to the individual''s baseline GABA level (R2=0.72). Mean glutamate concentrations did not change significantly with or without drug administration. In conclusion, localized 1H-MRS at 7 Tesla can be successfully applied to the measurement of GABA concentration and is sensitive to acute drug-induced changes in cortical GABA. Whether baseline GABA concentrations predict clinical efficacy of gabapentin is an area worthy of exploration.  相似文献   
86.
OBJECTIVE: The aim of the present study was to describe an inpatient psychosocial rehabilitation programme in rural New South Wales and to assess the effectiveness of the programme using measures of clinically significant change. METHOD: The first 88 patients with a schizophrenia spectrum disorder to enter the Manara Clinic and Turon House, New South Wales, psychosocial rehabilitation programmes were assessed at admission and discharge using the Brief Psychiatric Rating Scale, the Health of the Nation Outcome Scales, and the Kessler-10 self-report measure. RESULTS: Significant improvements in psychiatric symptomatology, psychosocial functioning, and psychological distress were found over the course of the inpatient stay. Clinical significance analyses using patients in the community as the reference group indicated a reliable and clinically significant improvement for 33% of inpatients on psychiatric symptomatology, 39% of inpatients on psychosocial functioning, and 21% of inpatients on psychological distress. CONCLUSIONS: The psychosocial rehabilitation programme provides clinically significant initial benefits for patients with severe mental illnesses. More attention needs to be paid to evaluating which components of psychosocial rehabilitation contribute most to these benefits. Follow-up evaluation is required to determine whether the benefits of this programme are sustained in the community.  相似文献   
87.
Curcumin, a major active component of turmeric, is known to induce apoptosis in several types of cancer cells, but little is known about its activity in chemoresistant cells. Hence, the aim of the present study was to investigate the anticancer properties of curcumin in cisplatin-resistant human ovarian cancer cells in vitro. The results indicated that curcumin inhibited the proliferation of both cisplatin-resistant (CR) and sensitive (CS) human ovarian cancer cells almost equally. Enhanced superoxide generation was observed in both CR and CS cells treated with curcumin. Curcumin induced G(2)/M phase cell-cycle arrest in CR cells by enhancing the p53 phosphorylation and apoptosis through the activation of caspase-3 followed by PARP degradation. Curcumin also inhibited the phosphorylation of Akt while the phosphorylation of p38 MAPK was enhanced. In summary, our results showed that curcumin inhibits the proliferation of cisplatin-resistant ovarian cancer cells through the induction of superoxide generation, G(2)/M arrest, and apoptosis.  相似文献   
88.
89.
90.
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