全文获取类型
收费全文 | 206篇 |
免费 | 11篇 |
国内免费 | 1篇 |
专业分类
218篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 13篇 |
2020年 | 7篇 |
2019年 | 9篇 |
2018年 | 6篇 |
2017年 | 9篇 |
2016年 | 8篇 |
2015年 | 9篇 |
2014年 | 16篇 |
2013年 | 21篇 |
2012年 | 12篇 |
2011年 | 17篇 |
2010年 | 6篇 |
2009年 | 3篇 |
2008年 | 7篇 |
2007年 | 10篇 |
2006年 | 6篇 |
2005年 | 10篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1997年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 4篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有218条查询结果,搜索用时 8 毫秒
1.
2.
3.
Jae-Hoon HwangJeong-A Choi Reda A.I. Abou-Shanab Booki MinHocheol Song Yongje Kim Eung Seok LeeByong-Hun Jeon 《Bioresource technology》2011,102(2):1051-1058
Anaerobic fermentation for hydrogen (H2) production was studied in a two-stage fermentation system fed with different ripened fruit feedstocks (apple, pear, and grape). Among the feedstocks, ripened apple was the most efficient substrate for cumulative H2 production (4463.7 mL-H2 L−1-culture) with a maximum H2 yield (2.2 mol H2 mol−1 glucose) in the first stage at a hydraulic retention time (HRT) of 18 h. The additional cumulative biohydrogen (3337.4 mL-H2 L−1-culture) was produced in the second stage with the reused residual substrate from the first stage. The major byproducts in this study were butyrate, acetate, and ethanol, and butyrate was dominant among them in all test runs. During the two-stage system, the energy efficiency (H2 conversion) obtained from mixed ripened fruits (RF) increased from 4.6% (in the first stage) to 15.5% (in the second stage), which indicated the energy efficiency can be improved by combined hydrogen production process. The RF could be used as substrates for biohydrogen fermentation in a two-stage (dark/dark) fermentation system. 相似文献
4.
Ahlam Sayout Aicha Ouarhach Reda Rabie Ilham Dilagui Nabila Soraa Abderrahmane Romane 《化学与生物多样性》2020,17(1)
The genus Lavandula is known for its different uses in traditional medicine. This study is interested in the chemical composition of Lavandulapedunculata subsp.atlantica (Braun‐Blanq. ) Romo as well as evaluating its antibacterial potential against multi‐resistant strains. The analysis of Lavandulaatlantica essential oil (LAEO) allows the identification of 47 components representing 93.6 % of all identified. The main constituent of LAEO was camphor (50.4 %), followed by fenchone (14.1 %) and camphene (5.6 %). The antibacterial assays revealed that LAEO was active against all the studied bacteria. A preliminary study of the relationship between certain terpenoids and antibacterial activity was also carried out in order to note the compound(s) that are responsible for LAEO's antibacterial activity. This study showed that the activity of the essential oil may be due to the presence of certain minor compounds such as carvone, considering the presence of the synergistic effect between the essential oil. 相似文献
5.
6.
7.
Goldman AS Guisinger VH Aikins M Amarillo ML Belizario VY Garshong B Gyapong J Kabali C Kamal HA Kanjilal S Kyelem D Lizardo J Malecela M Mubyazi G Nitièma PA Ramzy RM Streit TG Wallace A Brady MA Rheingans R Ottesen EA Haddix AC 《PLoS neglected tropical diseases》2007,1(1):e67
Background
Because lymphatic filariasis (LF) elimination efforts are hampered by a dearth of economic information about the cost of mass drug administration (MDA) programs (using either albendazole with diethylcarbamazine [DEC] or albendazole with ivermectin), a multicenter study was undertaken to determine the costs of MDA programs to interrupt transmission of infection with LF. Such results are particularly important because LF programs have the necessary diagnostic and treatment tools to eliminate the disease as a public health problem globally, and already by 2006, the Global Programme to Eliminate LF had initiated treatment programs covering over 400 million of the 1.3 billion people at risk.Methodology/Principal Findings
To obtain annual costs to carry out the MDA strategy, researchers from seven countries developed and followed a common cost analysis protocol designed to estimate 1) the total annual cost of the LF program, 2) the average cost per person treated, and 3) the relative contributions of the endemic countries and the external partners. Costs per person treated ranged from $0.06 to $2.23. Principal reasons for the variation were 1) the age (newness) of the MDA program, 2) the use of volunteers, and 3) the size of the population treated. Substantial contributions by governments were documented – generally 60%–90% of program operation costs, excluding costs of donated medications.Conclusions/Significance
MDA for LF elimination is comparatively inexpensive in relation to most other public health programs. Governments and communities make the predominant financial contributions to actual MDA implementation, not counting the cost of the drugs themselves. The results highlight the impact of the use of volunteers on program costs and provide specific cost data for 7 different countries that can be used as a basis both for modifying current programs and for developing new ones. 相似文献8.
Abdallah E. Abdallah Reda R. Mabrouk Maged Mohammed Saleh Al Ward Sally I. Eissa Eslam B. Elkaeed Ahmed B. M. Mehany Mariam A. Abo-Saif Ola A. El-Feky Mohamed S. Alesawy Mohamed Ayman El-Zahabi 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):573
Based on quinazoline, quinoxaline, and nitrobenzene scaffolds and on pharmacophoric features of VEGFR-2 inhibitors, 17 novel compounds were designed and synthesised. VEGFR-2 IC50 values ranged from 60.00 to 123.85 nM for the new derivatives compared to 54.00 nM for sorafenib. Compounds 15a, 15b, and 15d showed IC50 from 17.39 to 47.10 µM against human cancer cell lines; hepatocellular carcinoma (HepG2), prostate cancer (PC3), and breast cancer (MCF-7). Meanwhile, the first in terms of VEGFR-2 inhibition was compound 15d which came second with regard to antitumor assay with IC50 = 24.10, 40.90, and 33.40 µM against aforementioned cell lines, respectively. Furthermore, Compound 15d increased apoptosis rate of HepG2 from 1.20 to 12.46% as it significantly increased levels of Caspase-3, BAX, and P53 from 49.6274, 40.62, and 42.84 to 561.427, 395.04, and 415.027 pg/mL, respectively. Moreover, 15d showed IC50 of 253 and 381 nM against HER2 and FGFR, respectively. 相似文献
9.
Reda H. ElMazoudy Azza A. Attia 《Birth defects research. Part B, Developmental and reproductive toxicology》2012,95(6):444-459
Ginkgo extract, EGb 761 is known as a vasoregulatory variable for the conventional reproduction therapy. EGb 761 was orally administered in 0 (control), 3.7, 7.4, and 14.8 mg/kg bw/day for 28 days (thereafter mated with normal fertile male), from day 1 to day 7 of pregnancy or from the 10th to 18th day of pregnancy, respectively. Vaginal smears were performed daily. On 20th day of pregnancy, the females were killed by cervical dislocation and their kidneys, liver, brain, placenta, spleen and ovaries were removed and weighed. The ovaries were prepared for histological examinations, and then ovarian follicles were counted. Maternal toxicity, estrous cycle, reproductive hormones, ovarian follicle counts, resorption index, implantation index, fetal viability and fetuses, and placenta mean weights were evaluated. There was a dose‐dependent ovarian toxic effect of EGb 761. Ovarian follicle counts, resorption index, implantation index, fetal viability were significantly reduced in 14.8 mg/kg bw/day dose. Treatment with 14.8 mg/kg bw/day EGb 761 induced disruption of estrous cycle and caused maternal toxicity, in addition to fetal toxicity. Therefore, the data obtained indicate that Ginkgo biloba extract at 14.8 mg/kg bw/day dose level exhibit toxic effect on reproductive cyclicity and could have anti‐implantation and abotifacient properties in female mice. 相似文献
10.
Fatma Reda 《Planta》1976,130(3):265-268
Summary The soybean callus assay was used to study the effect of vernalization on the endogenous cytokinin levels of the grains of winter wheat (Triticum vulgare L.), cv. Ferto and Fema. Vernalization of the grains was carried out at 3° C in the dark for 0, 9, 18, 27, 36 and 45 days. Cytokinin activities could be detected in both the aqueous and butanol extracts of vernalized grains of both cultivars. It is suggested that flowering of winter wheat may involve changes in the levels of endogenous cytokinins during vernalization. 相似文献