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   62807篇
  免费   3390篇
  国内免费   141篇
耳鼻咽喉   623篇
儿科学   1718篇
妇产科学   1590篇
基础医学   9945篇
口腔科学   672篇
临床医学   5414篇
内科学   14083篇
皮肤病学   1233篇
神经病学   5615篇
特种医学   2067篇
外国民族医学   32篇
外科学   9052篇
综合类   327篇
一般理论   23篇
预防医学   4295篇
眼科学   992篇
药学   4071篇
中国医学   114篇
肿瘤学   4472篇
  2023年   253篇
  2022年   214篇
  2021年   796篇
  2020年   487篇
  2019年   886篇
  2018年   1462篇
  2017年   1010篇
  2016年   1064篇
  2015年   1327篇
  2014年   1447篇
  2013年   2339篇
  2012年   3732篇
  2011年   3793篇
  2010年   2082篇
  2009年   1780篇
  2008年   3618篇
  2007年   3716篇
  2006年   3635篇
  2005年   3811篇
  2004年   3658篇
  2003年   3474篇
  2002年   3487篇
  2001年   1503篇
  2000年   1540篇
  1999年   1284篇
  1998年   552篇
  1997年   491篇
  1996年   436篇
  1995年   444篇
  1994年   381篇
  1993年   377篇
  1992年   831篇
  1991年   693篇
  1990年   701篇
  1989年   711篇
  1988年   624篇
  1987年   609篇
  1986年   538篇
  1985年   535篇
  1984年   422篇
  1983年   371篇
  1982年   267篇
  1981年   283篇
  1980年   242篇
  1979年   319篇
  1978年   236篇
  1977年   228篇
  1976年   200篇
  1975年   196篇
  1974年   194篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
BackgroundThe cost-effectiveness of the 70-gene signature (70-GS) (MammaPrint®) has earlier been estimated using retrospective validation data. Based on the prospective 5-year survival data of the microarRAy-prognoSTics-in-breast-cancER (RASTER) study, the aim here was to evaluate the cost-effectiveness reflecting the actual use in clinical practice, including reality-based compliance rates.MethodsCosts and outcomes (quality-adjusted-life-years (QALYs)) were calculated in node-negative (N?) patients included in the RASTER study (n = 427). Sensitivity and specificity of the 70-gene and Adjuvant! Online (AO) were based on 5-year distant-disease-free survival (DDFS). Subgroup analyses were performed for two groups for whom benefit of the 70-gene had earlier been reported: (1) ductal, oestrogen receptor-positive (ER+), tumour diameter 10–30 mm, grade II, age 40–70; (2) ductal, oestrogen receptor-positive, tumour diameter 5–30 mm, grade II/III and age 40–70.ResultsBased on 5-year survival data, the cost-effectiveness of the 70-gene signature versus AO was prospectively confirmed. The total health care costs per patient were €26,786 for the 70-gene and €29,187 for AO. The quality adjusted life years yielded 12.49 and 11.88, respectively. The subgroups retrieved slightly higher life gains and higher costs, but all resulted finally in a favourable position for the 70-gene signature.ConclusionsThe use of the 70-gene signature, as judged appropriate by doctors and patients and supported by a low risk 70-gene signature as an oncological safe choice, was also found to be cost-effective.  相似文献   
992.
Although vincristine (VCR) is sometimes prescribed for newly diagnosed immune thrombocytopenia (ITP), its efficacy in refractory ITP and sustained efficacy has yet to be demonstrated. We describe our clinical experience and recommend vincristine's correct place in ITP management. This retrospective study analysed data from 35 patients with newly diagnosed (ND), persistent (P) or chronic (C) ITP treated with VCR. The initial response rate, defined as >30 × 109 platelets/L, reached 86% after a median of 7 [interquartile range (IQR) 6–13] days. In ND and P ITP, even when previous therapies were inefficient, initial response was 87.5%, suggesting that this treatment could be used particularly in rescue. Median survival time, without failure or relapse, was 15 months (Kaplan–Meier curve). Predictive factors (univariate analysis) of an initial and long‐term response were a small number of prior treatments received. However, at 2 yr, only seven patients had sustained response. Eight (23%) patients experienced adverse events: neuropathy for seven and bowel obstruction for one. Vincristine efficacy in ITP was confirmed, and it could be a good strategy for treating resistant ITP, especially in emergencies. In this era of new therapeutics, VCR deserves to remain on the list of ITP treatments because of its initial efficacy, safety and low cost.  相似文献   
993.
994.
A woman with a medical history of breast cancer presented with chronic pain of the right hemithorax. To alleviate pain, a continuous paravertebral block was performed using a pigtail end catheter, introduced using ultrasound visualization (transversal technique at the inferior articular process of T6). Complete pain relief was observed. A few hours later, urinary retention was diagnosed and discharge from the ambulatory setting was canceled. On the following day, a new injection of local anesthetics through the catheter triggered paresthesia in the contralateral leg and a new urinary retention was diagnosed. A CT scan confirmed the epidural misplacement of the catheter. The latter was withdrawn, and the patient was released to home after the complete disappearance of her neurological symptoms. This case report highlights the risk of inadvertently misplacing the catheter into the epidural space during thoracic paravertebral block, even with a “pigtail” distal end type of catheter.  相似文献   
995.
996.
997.
We have investigated the localization and regulation of growth hormone (GH) receptor-related proteins in the ovine mammary gland. Using a new rabbit polyclonal antibody (7122A) directed against the recombinant extracellular domain of GH receptor (GHR-ECD) for western blot assays, we found two bands with apparent molecular weights of 70,000 and 50–60,000?Da in ovine mammary gland solubilized proteins. The 70,000-protein was consistent with a membrane GH receptor form deprived of post-translational modifications such as phosphorylation, glycosylation or ubiquitin binding. The 50–60,000?Da was consistent with soluble GH binding protein, generated by the cleavage of membrane GH receptor. The intensity of related GHR proteins increased slightly throughout mammary gland development and was correlated with the amount of GHR immunoreactivity observed in the mammary gland sections. Moreover, a temporal and spatial regulation of GHR immunoreactivity was found in alveolar epithelial cells. Clearly, marked GHR immunoreactivity was associated with the apical membranes of alveolar epithelial cells at lactation. The up-regulation of related GHR proteins during the differentiation of mammary tissue supports the hypothesis that GH may act specifically via its own receptors. In ovine mammary cells, GH was able to promote a time-dependent activation of MAP kinases such as prolactin (Prl) and placental lactogen (PL). GH was also able to promote slight and transient Stat5 DNA-binding activity. Differences in the time dependence of Stat5 DNA-binding activation by the three different ligands, GH, Prl and PL, were found. All these results emphasize the direct action of GH on ovine mammary cells and highlight the specificity of action of this ligand.  相似文献   
998.
ObjectivesSexual dysfunction is currently the most common complication of cancer. Most of the time, patients who are concerned by locally advanced cervical cancer are in a period of sexual activity. The primary objective of this study was to assess the quality of life and sexual function of patients with locally advanced cervical cancer who were in remission. The secondary objective was to correlate the prognostic factor with sexual dysfunction.Patients and methodsThis multicentric and prospective study included the patients with locally advanced cervical cancer diagnosis from three centres. Thirty-one patients with diagnosis of locally advanced cervical cancer were enrolled from February 2007 to October 2008. The mean age was 49 years old. Inclusion criteria were to have received the standard therapy by chemoradiotherapy and have been in remission for 2 years. Both self-administered questionnaires BISF-W and EORTC QLQ-CX24 allowed scoring quality of life and sexual function.ResultsThe rate of completion was 42%. The results confirmed that sexual function was impaired in accordance with sexual satisfaction. After therapy, the frequency of sexual activity was decreased. The functional quality of life was significantly correlated with sexual function. Marital status was a significant prognostic factor. Age, stage and the type of centre were not.Discussion and conclusionThis preliminary study suggests that after 2 years of remission of the disease after treatment, patients and their partners need to be helped as regards their sexual function. We propose to perform a prospective study on a larger cohort.  相似文献   
999.
1000.
Background. Routine lateral turning of patients has become an accepted standard of care to prevent complications of immobility. The haemodynamic and oxygenation effects for patients in both lateral positions (45°) are still a matter of debate. We aimed to study the effect of these positions on blood pressure, heart rate and oxygenation in a general intensive care population. Design. Observational study. Method. Twenty stable intensive care unit patients had intra‐arterial blood pressure recordings in the supine and lateral positions with the correction of hydrostatic height compared with a fixed reference point (phlebostatic level). A multilevel model was used to analyse the data. Results. Mean arterial pressure readings in the lateral positions were, on average, 5 mmHg higher than in the supine position (p < 0·001). There were no significant differences between mean arterial pressure recordings in the left and right lateral position (p = 1·0). No important differences in oxygenation and heart rate were observed. After correction for covariates, the effects persisted. Conclusion. Our study demonstrated an increase, albeit small, in blood pressure in the lateral positions. No major differences between the left and right lateral position were found. No important differences in oxygenation and heart rate were observed. Relevance to clinical practice. Turning haemodynamically stable patients in the intensive care unit has no important effects on blood pressure measurements when continuous hydrostatic height correction is applied.  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