全文获取类型
收费全文 | 1553篇 |
免费 | 76篇 |
国内免费 | 1篇 |
出版年
2022年 | 11篇 |
2021年 | 22篇 |
2020年 | 15篇 |
2019年 | 18篇 |
2018年 | 26篇 |
2017年 | 29篇 |
2016年 | 28篇 |
2015年 | 44篇 |
2014年 | 59篇 |
2013年 | 77篇 |
2012年 | 107篇 |
2011年 | 81篇 |
2010年 | 64篇 |
2009年 | 36篇 |
2008年 | 59篇 |
2007年 | 68篇 |
2006年 | 60篇 |
2005年 | 50篇 |
2004年 | 40篇 |
2003年 | 43篇 |
2002年 | 36篇 |
2001年 | 50篇 |
2000年 | 40篇 |
1999年 | 42篇 |
1998年 | 20篇 |
1997年 | 19篇 |
1996年 | 13篇 |
1995年 | 19篇 |
1994年 | 18篇 |
1993年 | 11篇 |
1992年 | 25篇 |
1991年 | 38篇 |
1990年 | 34篇 |
1989年 | 29篇 |
1988年 | 31篇 |
1987年 | 26篇 |
1986年 | 15篇 |
1985年 | 12篇 |
1984年 | 12篇 |
1983年 | 13篇 |
1982年 | 11篇 |
1981年 | 13篇 |
1979年 | 19篇 |
1978年 | 12篇 |
1974年 | 9篇 |
1973年 | 15篇 |
1972年 | 11篇 |
1971年 | 15篇 |
1970年 | 13篇 |
1969年 | 14篇 |
排序方式: 共有1630条查询结果,搜索用时 15 毫秒
991.
Melody J. Xu Mariana Cooke David Steinmetz Giorgos Karakousis Deeksha Saxena Edmund Bartlett Xiaowei Xu Stephen M. Hahn Jay F. Dorsey Gary D. Kao 《PloS one》2015,10(3)
Background
Circulating tumor cell (CTC) detection and genetic analysis may complement currently available disease assessments in patients with melanoma to improve risk stratification and monitoring. We therefore sought to establish the feasibility of a telomerase-based assay for detecting and isolating live melanoma CTCs.Methods
The telomerase-based CTC assay utilizes an adenoviral vector that, in the presence of elevated human telomerase activity, drives the amplification of green fluorescent protein. Tumor cells are then identified via an image processing system. The protocol was tested on melanoma cells in culture or spiked into control blood, and on samples from patients with metastatic melanoma. Genetic analysis of the isolated melanoma CTCs was then performed for BRAF mutation status.Results
The adenoviral vector was effective for all melanoma cell lines tested with sensitivity of 88.7% (95%CI 85.6-90.4%) and specificity of 99.9% (95%CI 99.8-99.9%). In a pilot trial of patients with metastatic disease, CTCs were identified in 9 of 10 patients, with a mean of 6.0 CTCs/mL. At a cutoff of 1.1 CTCs/mL, the telomerase-based assay exhibits test performance of 90.0% sensitivity and 91.7% specificity. BRAF mutation analysis of melanoma cells isolated from culture or spiked control blood, or from pilot patient samples was found to match the known BRAF mutation status of the cell lines and primary tumors.Conclusions
To our knowledge, this is the first report of a telomerase-based assay effective for detecting and isolating live melanoma CTCs. These promising findings support further studies, including towards integrating into the management of patients with melanoma receiving multimodality therapy. 相似文献992.
993.
Pallavi Sinha Vikas K. Singh Rachit K. Saxena Sandip M. Kale Yuqi Li Vanika Garg Tang Meifang Aamir W. Khan Kyung Do Kim Annapurna Chitikineni K. B. Saxena C. V. Sameer Kumar Xin Liu Xun Xu Scott Jackson Wayne Powell Eviatar Nevo Iain R. Searle Mukesh Lodha Rajeev K. Varshney 《Plant biotechnology journal》2020,18(8):1697-1710
994.
995.
K Pravina K R Ravindra K S Goudar D R Vinod A J Joshua P Wasim K Venkateshwarlu V S Saxena A Amit 《Phytomedicine》2007,14(5):301-308
BacoMind is an enriched phytochemical composition of Bacopa monniera (B. monniera), a common medicinal plant used in the traditional systems of medicine as a memory-enhancing agent. BacoMind was standardized with reference to bioactive compounds and was evaluated for short-term safety and tolerability in healthy adult volunteers. The study plan employed randomized, open label, dose escalation design. Each of 23 participants were orally given one single capsule of BacoMind daily for 30 days, i.e., 300 mg for first 15 days and 450 mg for next 15 days. Detailed examination of clinical, hematological, biochemical and electrocardiographic parameters done in pre and post-treatment periods did not indicate any untoward effects in any of the treated volunteers. Mild adverse events related to gastrointestinal system were observed in the trial, which subsided spontaneously. BacoMind was found to meet the safety criteria at the dose administered for the given duration of trial period in healthy adult volunteers. 相似文献
996.
The study of the flood-waters revealed that the breach of irrigation channels due to heavy downpour, triggered the floods, as the first flood-waters largely contained characteristic riverine fauna. Later on, the riverine fauna was outnumbered by pond fauna indicating the overflow from ponds, adding to the amount of flood-waters. The flood-waters play a significant role in the distribution of animals in general and vectors in particular. The chief vectors included Cyclops, Lymnaea, Planorbis and five genera of fishes. Pockets of stagnant flood-water provide a breeding ground for mosquitoes to create a future nuisance. The faunal study of flood-waters offers a proof to their origin, which otherwise requires a manual survey. 相似文献
997.
998.
The control of malaria has been complicated by the increasing resistance of malarial parasites to multiple drugs. However, artemisinin-based drugs offer hope in the fight against drug-resistant parasites. The mode of action of these drugs remains unclear, but evidence suggests a role for free radicals in their mechanism of action. In this study, we examined the relationship between the intracellular levels of glutathione (GSH) and antioxidant enzymes and resistance to the artemisinin-based drug arteether in experimentally selected arteether-resistant Plasmodium vinckei. GSH plays a critical role in the detoxification and protection of cells against oxidative stress. Our comparative studies showed a significant (2.9-fold) increase in the GSH level in arteether-resistant parasites as compared to arteether-sensitive parasites. Simultaneously, significantly increased activities of glutathione reductase, glutathione-S transferase and glucose-6-phosphate dehydrogenase and decreased activity of superoxide dismutase were recorded in resistant parasites; the activity of glutathione peroxidase was comparable in arteether-sensitive and -resistant parasites. Artemisinin derivatives act by generating free radicals and our results indicate that glutathione's antioxidant effects may counteract that drug effect and thereby contribute to the parasites' resistance to arteether and other artemisinin-based antimalarials. 相似文献
999.
The complexity of large computer systems has raised unprecedented challenges for system management. In practice, operators
often collect large volume of monitoring data from system components and set up many rules to check data and trigger alerts.
However, the alerts from various rules usually have different problem reporting accuracy because their thresholds are often
manually set based on operators’ experience and intuition. Meantime, due to system dependencies, a single problem may trigger
many alerts at the same time in large systems and the critical question is which alert should be analyzed first in the following
problem determination process. In this paper, we propose a novel peer review mechanism to rank the importance of alerts and
the top ranked alerts are more likely to be true positives. After comparing a metric value against its threshold to generate
alerts, we also compare the value with the equivalent thresholds from many other rules to determine the importance of alerts.
Our approach is evaluated with a real test bed system and experimental results are also included to demonstrate its effectiveness. 相似文献
1000.