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571.
Maolu Tian Yanjun Long Yang Hong Xiangyan Zhang Yan Zha 《Environmental microbiology》2020,22(8):3588-3592
We reported 20 cases of discharged COVID-19 patients whose RT-PCR test results showed ‘re-positive’. After finding ‘re-positive’, these patients were admitted to hospital for the second time and were followed up until the end of May 2020. We recorded detailed treatment and follow-up process, and collected relevant data. The possible causes and potential clinical significance of this phenomenon are discussed. 相似文献
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Peng He Bing Zhang Yuan Zou Yan Zhang Zhihao Zha Yali Long Jia Qiu Wanqing Shen Xiaoping Lin Zhoulei Li Xiangsong Zhang 《Translational oncology》2021,14(5)
L-ascorbic acid (AA) was reported to have an anti-cancer effect over 40 years. In recent years, several ongoing clinical trials are exploring the safety and efficacy of intravenous high-dose AA for cancer treatment. The lack of appropriate imaging modality limits the identification of potentially suitable patients for AA treatment. This study focuses on identifying AA-sensitive tumor cells using molecular imaging. 6-Deoxy-6-[18F] fluoro-L-ascorbic Acid (18F-DFA), a structural analog of AA, was synthesized and labeled to visualize the metabolism of AA in vivo. Colorectal cancer (CRC) cell lines with high and low expression of sodium-dependent vitamin C transporters 2 (SVCT2) were used for a series of cellular uptake tests. PET imaging was performed on xenograft tumor-bearing mice. More AA uptake was observed in CRC cells with high SVCT2 expression than in cells with low SVCT2 expression. The substrate (unlabeled AA) can competitively inhibit the 18F-DFA tracer uptake by CRC cells. The biodistribution of 18F-DFA in mice showed high radioactivity was seen in organs such as adrenal glands, kidneys, and liver that were known to have high concentrations of AA. Both PET imaging and tissue distribution showed that cancer cells with high SVCT2 expression enhanced the accumulation of 18F-DFA in mice after tumor formation. Immunohistochemistry was used to verify the corresponding results. As a radiotracer, 18F-DFA can provide powerful imaging information to identify tumor with high affinity of AA, and SVCT2 can be a potential biomarker in this process. 相似文献
575.
Wei‐Guang Shan Zhao‐Ying Wu Wei‐Wei Pang Lie‐Feng Ma You‐Min Ying Zha‐Jun Zhan 《化学与生物多样性》2015,12(11):1718-1724
One new diketopiperazine alkaloid amauromine B ( 1 ), along with three known meroterpenoids, austalide B ( 2 ), austalides N and O ( 3 and 4 ), and two known steroids ( 5 and 6 ), was isolated and identified from the culture broth of the fungus Aspergillus terreus 3.05358. Their structures were elucidated by extensive spectroscopic techniques, including 2D‐NMR and MS analysis, the absolute configuration of 1 was unambiguously established by single crystal X‐ray diffraction analysis. All the isolates were evaluated for their inhibitory effects on α‐glucosidase. Amauromine B ( 1 ) and austalide N ( 3 ) exhibited more potent α‐glucosidase inhibitory activities than the positive control acarbose. 相似文献
576.
Xiaowei Fu Le Hong Zhengjiang Yang Yi Tu Wanpeng Xin Ming Zha Shuju Tu Gen Sun Yong Li Weidong Xiao 《Journal of cellular and molecular medicine》2020,24(22):13020
Although miR‐148a‐3p has been reported to function as a tumour suppressor in various cancers, the molecular mechanism of miR‐148a‐3p in regulating epithelial‐to‐mesenchymal transition (EMT) and stemness properties of pancreatic cancer (PC) cells remains to be elucidated. In the present study, we demonstrated that miR‐148a‐3p expression was remarkably down‐regulated in PC tissues and cell lines. Moreover, low expression of miR‐148a‐3p was associated with poorer overall survival (OS) in patients with PC. In vitro, gain‐of‐function and loss‐of‐function experiments showed that miR‐148a‐3p suppressed EMT and stemness properties as well as the proliferation, migration and invasion of PC cells. A dual‐luciferase reporter assay demonstrated that Wnt1 was a direct target of miR‐148a‐3p, and its expression was inversely associated with miR‐148a‐3p in PC tissues. Furthermore, miR‐148a‐3p suppressed the Wnt/β‐catenin pathway via down‐regulation of Wnt1. The effects of ectopic miR‐148a‐3p were rescued by Wnt1 overexpression. These biological functions of miR‐148a‐3p in PC were also confirmed in a nude mouse xenograft model. Taken together, these findings suggest that miR‐148a‐3p suppresses PC cell proliferation, invasion, EMT and stemness properties via inhibiting Wnt1‐mediated Wnt/β‐catenin pathway and could be a potential prognostic biomarker as well as a therapeutic target in PC. 相似文献
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