全文获取类型
收费全文 | 2064篇 |
免费 | 86篇 |
出版年
2024年 | 1篇 |
2023年 | 44篇 |
2022年 | 30篇 |
2021年 | 65篇 |
2020年 | 50篇 |
2019年 | 60篇 |
2018年 | 74篇 |
2017年 | 66篇 |
2016年 | 90篇 |
2015年 | 77篇 |
2014年 | 135篇 |
2013年 | 195篇 |
2012年 | 155篇 |
2011年 | 188篇 |
2010年 | 133篇 |
2009年 | 103篇 |
2008年 | 107篇 |
2007年 | 100篇 |
2006年 | 106篇 |
2005年 | 81篇 |
2004年 | 81篇 |
2003年 | 60篇 |
2002年 | 49篇 |
2001年 | 15篇 |
2000年 | 15篇 |
1999年 | 12篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1976年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有2150条查询结果,搜索用时 31 毫秒
971.
Deniz Ekinci Hüseyin Çavdar Oktay Talaz Murat Şentürk Claudiu T. Supuran 《Bioorganic & medicinal chemistry》2010,18(10):3559-3563
Carbonic anhydrase (CA, EC 4.2.1.1) inhibitors (CAIs) are a class of pharmaceuticals used as antiglaucoma agents, diuretics, antiepileptics, in the management of mountain sickness, gastric and duodenal ulcers, neurological disorders, or osteoporosis. We report here the inhibitory capacities of some organic nitrates against two human (hCA) isozymes, hCA I and hCA II. The IC50 values of compounds 1–12 against hCA I ranged between 7.13 mM and 124 mM, and against hCA II between 65.1 μM and 0.79 mM. Nitrate esters are thus interesting hCA I and II inhibitors, and might be used as leads for generating enzyme inhibitors eventually targeting other isoforms which have not been assayed yet for their interactions with such agents. 相似文献
972.
Mehmet Kayrak Zeynettin Kaya Enes Elvin Gul Mehmet S Ulgen Mehmet Yazici Serter Gumus Yahya Paksoy 《Indian pacing and electrophysiology journal》2010,10(4):179-183
Within recent years, much scientific attention has been devoted to adults with congenital heart disease (CHD) and probable complications. Congenitally corrected transposition of the great arteries (CCTGA) is a rare, complex form of congenital heart defects. CCTGA is characterized by atrioventricular (AV) and ventriculoarterial (VA) discordance and, hence, by a physiologically normal direction of blood flow. The development of complete AV block and global ventricular dysfunction has been identified as the cause of cardiac death. Although the development of arrhythmias represents a major cause of morbidity and mortality in patients with CHD, the account of all implantations of pacemakers and implantable cardioverter defibrillators (ICD) is less than one percent. This paper presents a case of CCTGA with severe rhythm disorders, discusses probable treatment options, and offers indications of ICD implantation in patients with CHD. 相似文献
973.
974.
Zahoor Ahmad Ejaz Ahmad Waraich Celaleddin Barutçular Akbar Hossain Murat Erman Fatih ÇIĞ Hany Gharib Ayman EL Sabagh 《Phyton》2020,89(3):529-539
The main objective of the research is to assess the role of foliar application of silicon (Si) for enhancing the survival ability of wheat under drought stress
through improving its morphology, physicochemical and antioxidants activities.
Treatments were five doses of Si at the rate of 2, 4, 6 and 8 mM and a control. After
completion of seeds germination, pots were divided into four distinct groups at various field capacity (FC) levels, such as 100% FC (well-irrigated condition), 75% FC
(slight water deficit), 50% FC (modest water deficit) and 25% FC (severe water deficit stress condition). Foliar application of Si at the rate of 2, 4, 6 and 8 mM and a
control were given after 30 days of sowing at the tillering stage of wheat. Findings
of the present investigation indicated that increasing the level of water deficit stress
reduced the morphological parameters (such as root and shoot fresh and dry-biomass weight) and physico-biochemical events ((such as chlorophyll contents by
estimating SPAD value), total free amino acid (TFAA), total soluble sugar (TSS),
total soluble protein (TSP), total proline (TP), CAT (catalase), POD (peroxidase),
SOD (superoxide dismutase) and APX (ascorbate peroxidase)) of wheat; while
foliar application of Si at 6 mM at tillering stage enhanced the drought tolerance
in wheat by increasing morphology and physiochemical characters under all levels
of drought stress. Similarly, antioxidants activities in wheat also enhanced by the
application of Si at 6 mM under normal as well as all drought stress levels. Therefore, it may be concluded that foliar application of Si at 6 mM at the tillering stage
of wheat is an important indication for increasing the drought tolerance by improving the morphology, physico-biochemical and antioxidants activities in plants under
deficit water (drought) conditions. 相似文献
975.
AbstractToday, the need for energy is increasing and fossil fuels are constituting one of the most important energy sources in the world. Therefore, the efficient use of fossil fuels has become inevitable. In order to better use the opportunities offered by nature, we have turned to nature’s own resources. In this study, fungal strains of potential use in coal processing technology, isolated from Turkey’s largest lignite mine and identified. Our goal was to obtain active isolates for the biotechnological applications using the mine’s own source. For this aim, lignite samples were collected from different regions of the Af?in–Elbistan lignite mine, isolation studies were done and eventually, distinguished fungal isolates were identified by using conventional and molecular techniques. Hereby, fungal biodiversity of Turkey’s largest lignite mine has been investigated for the first time. Furthermore, 20 fungal isolates belong to Alternaria, Aspergillus, and Penicillium genera were cultured to provide resources for the development of future biotechnological coal processing techniques. 相似文献
976.
Cavdar Zahide Oktan Mehmet Asi Ural Cemre Calisir Meryem Kocak Ayse Heybeli Cihan Yildiz Serkan Arici Aylin Ellidokuz Hulya Celik Ali Yilmaz Osman Sarioglu Sulen Cavdar Caner 《Biological trace element research》2020,193(2):483-493
Biological Trace Element Research - We aimed to investigate the protective effect of alpha lipoic acid (ALA), a powerful antioxidant, against oxidative kidney damage induced by iron overload in... 相似文献
977.
Çağlar Akçay S. Elizabeth Campbell Saethra Darling Michael D. Beecher 《Ethology : formerly Zeitschrift fur Tierpsychologie》2020,126(7):694-703
In most songbirds, the processes of song learning and territory establishment overlap in the early life and a young bird usually winds up with songs matching those of his territorial neighbors in his first breeding season. In the present study, we examined the relationships among the timing of territory establishment, the pattern of song learning and territorial success in a sedentary population of song sparrows (Melospiza melodia). Males in this population tend to learn their songs from their neighbors and consequently they show high song sharing with neighbors and use these shared songs preferentially in interactions with them. Males also show significant variation in the timing of territory establishment, ranging from their natal summer to the next spring. Using a three-year dataset, we found that the timing of territory establishment did not systematically affect the composition of the song repertoire of the tutee: early establishers and late establishers learned equally as much from their primary tutors and had a similar number of tutors and similar repertoire sizes, nor did timing of territory establishment affect subsequent survival on territory. Therefore, the song-learning program of song sparrows seems versatile enough to lead to high song sharing even for birds that establish territories relatively late. 相似文献
978.
Demirci Tunhan Akçay Ufuk Çelikkol Göktürk Baydar Nilgün 《In vitro cellular & developmental biology. Plant》2020,56(6):875-881
In Vitro Cellular & Developmental Biology - Plant - Echinacea (Echinacea purpurea L.), also known as purple coneflower, is one of the important medicinal plants commonly used for respiratory... 相似文献
979.
Lashkarinia S. Samaneh Çoban Gürsan Ermek Erhan Çelik Merve Pekkan Kerem 《Biomechanics and modeling in mechanobiology》2020,19(5):1897-1915
Biomechanics and Modeling in Mechanobiology - The microstructure for mature vessels has been investigated in detail, while there is limited information about the embryonic stages, in spite of their... 相似文献
980.
Muhammad Abu Bakar Zia Ufuk Demirel Muhammad Azhar Nadeem Mehmet Emin aliskan 《Physiology and Molecular Biology of Plants》2020,26(5):1003-1020
Potato is one of the most important food crops all over the world. Breeding activities for this crop are mainly aimed to improve the quality and yield of tuber. However, genetic architecture of various traits contributing to the quality and yield of potato are not yet completely understood. Genome wide association studies provides a broader way to identify the genomic regions associated with various traits. Panels of 237 tetraploid potato genotypes from different countries were grown for two consecutive years 2016 and 2017 at experimental research area of Potato research center Niğde, Turkey. A genome wide association study using SolCAP 12K array was performed for various morpho-agronomic traits. Structure algorithm and neighborhood joining analysis clearly divided all genotypes into 4 clusters on the basis of their origin. For the marker trait association, Mixed Linear Model in TASSEL was performed and 36 genomic regions were found for the traits under study. The mean r2 value was found to be 0.92 and mean significant LD was 47.5% in the populations. LD patterns reflected the breeding history of potato. The findings of present study provide a framework which could be useful for future potato breeding programs to enhance the production and to reduce the challenges in the coming years to feed world’s population. 相似文献