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51.
Chris Barichievy Rob Sheldon Tim Wacher Othman Llewellyn Mohammed Al-Mutairy Abdulaziz Alagaili 《Saudi Journal of Biological Sciences》2018,25(2):290-292
Conservation in the Kingdom of Saudi Arabia is relatively young, yet have made considerable gains in conservation through strategic proclamation and reintroductions. Changes in land use, illegal hunting and competition with domestic stock has decimated the native ungulates, meaning that the survival of the native ungulate species is now completely dependent on protected area network. The challenge is to sustain this network to make meaningful conservation impact into the future. We review the status of ungulate conservation in Saudi Arabia and highlight that the conservation strategy is well developed. The major challenge faced in conservation in Saudi Arabia now is to implement what has been sanctioned. 相似文献
52.
In a survey of starch-based foods sampled from retail outlets in Malaysia, fungal colonies were mostly detected in wheat flour
(100%), followed by rice flour (74%), glutinous rice grains (72%), ordinary rice grains (60%), glutinous rice flour (48%)
and corn flour (26%). All positive samples of ordinary rice and glutinous rice grains had total fungal counts below 103 cfu/g
sample, while among the positive rice flour, glutinous rice flour and corn flour samples, the highest total fungal count was
more than 103 but less than 104 cfu/g sample respectively. However, in wheat flour samples total fungal count ranged from
102 cfu/g sample to slightly more than 104 cfu/g sample. Aflatoxigenic colonies were mostly detected in wheat flour (20%),
followed by ordinary rice grains (4%), glutinous rice grains (4%) and glutinous rice flour (2%). No aflatoxigenic colonies
were isolated from rice flour and corn flour samples. Screening of aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin
G2 using reversed-phase HPLC were carried out on 84 samples of ordinary rice grains and 83 samples of wheat flour. Two point
four percent (2.4%) of ordinary rice grains were positive for aflatoxin G1 and 3.6% were positive for aflatoxin G2. All the
positive samples were collected from private homes at concentrations ranging from 3.69–77.50 μg/kg. One point two percent
(1.2%) of wheat flour samples were positive for aflatoxin B1 at a concentration of 25.62 μ};g/kg, 4.8% were positive for aflatoxin
B2 at concentrations ranging from 11.25–252.50 μg/kg, 3.6% were positive for aflatoxin G1 at concentrations ranging from 25.00–289.38
μg/kg and 13.25% were positive for aflatoxin G2 at concentrations ranging from 16.25–436.25 μg/kg. Similarly, positive wheat
flour samples were mostly collected from private homes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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The present study reports weight-length (W-L) relationships and discusses the relative growth of the banded murex (Hexaplex trunculus) from intertidal and offshore areas of the Gulf of Gabès (southern Tunisia). Overall, 9634 H. trunculus were sampled (6608 from intertidal and 3026 from offshore), with both populations comprising broad ranges in shell length (intertidal: 13.6–78.5 mm; offshore: 22.9–91.1 mm) and total weight (intertidal: 0.2–63.8 g; offshore: 0.6–92.5 g). In both populations, W-L relationships were highly significant and the morphometric parameters were highly correlated (intertidal: r?=?0.967; offshore: r?=?0.973). Relative growth was significantly different between populations, with intertidal H. trunculus displaying a negative allometry (b?=?2.962) and offshore H. trunculus exhibiting isometric growth (b?=?3.013). Factors influencing total weight (soft-body weight and shell weight) and potentially responsible for differences in W-L relationships and relative growth between populations were discussed. In addition, a useful comparative analysis for fisheries biology, assessment and management purposes was performed with analogous information from other populations of H. trunculus from the Mediterranean Sea and the Atlantic Ocean. 相似文献
55.
Sana Ben Othman Nakako Katsuno Akemi Kitayama Makoto Fujimura Kohji Kitaguchi 《Free radical research》2016,50(9):949-958
Oxidative stress is involved in the development of aging-related diseases, such as neurodegenerative diseases. Dietary antioxidants that can protect neuronal cells from oxidative damage play an important role in preventing such diseases. Previously, we reported that water-soluble fractions purified from defatted sesame seed flour exhibit good antioxidant activity in vitro. In the present study, we investigated the protective effects of white and gold sesame seed water-soluble fractions (WS-wsf and GS-wsf, respectively) against 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) and hydrogen peroxide (H2O2) induced oxidative stress in human neuroblast SH-SY5Y cells. Pretreatment with WS-wsf and GS-wsf did not protect cells against AAPH-induced cytotoxicity, while simultaneous co-treatment with AAPH significantly improved cell viability and inhibited membrane lipid peroxidation. These results suggest that WS-wsf and GS-wsf protect cells from AAPH-induced extracellular oxidative damage via direct scavenging of peroxyl radicals. When oxidative stress was induced by H2O2, pretreatment WS-wsf and GS-wsf significantly enhanced cell viability. These results suggest that in addition to radical scavenging, WS-wsf and GS-wsf enhance cellular resistance to intracellular oxidative stress by activation of the Nrf-2/ARE pathway as confirmed by the increased Nrf2 protein level in the nucleus and increased heme oxygenase 1 (HO-1) mRNA expression. The roles of ferulic and vanillic acids as bioactive antioxidants in these fractions were also confirmed. In conclusion, our results indicated that WS-wsf and GS-wsf, which showed antioxidant activity in vitro, are also efficient antioxidants in a cell system protecting SH-SY5Y cells against both extracellular and intracellular oxidative stress. 相似文献
56.
Hamed Zakikhani Mohd. Khanif Yusop Mohamed Musa Hanafi Radziah Othman Amin Soltangheisi 《Chemical Speciation and Bioavailability》2016,28(1-4):170-181
Intermittently submergence and drainage status of paddy fields can cause alterations in morphological and chemical characteristics of soils. We conducted a sequential fractionation study to provide an insight into solubility of Sulfur (S) and Molybdenum (Mo) in flooded alluvial paddy soils. The samples (0–15 and 15–30 cm) were taken from marine and riverine alluvial soils in Kedah and Kelantan areas, respectively, and were sequentially extracted with NaHCO3, NaOH, HCl, and HClO4–HNO3. Total S in upper and lower layers of Kedah and Kelantan ranged between 273 and 1121 mg kg?1, and 177 to 1509 mg kg?1, respectively. In upper layers and subsoil of Kedah, average total Mo were 0.34 and 0.27 mg kg?1, respectively. Average total Mo in Kelantan were 0.25 mg kg?1 (surface layer) and 0.28 mg kg?1 (subsoil). Cation exchange capacity (CEC) was positively correlated with plant available amounts of Mo in upper layers of Kedah area. Also, total and medium-term plant-available S was correlated with total carbon (C) at lower layers of Kelantan soil series. But in surface layers of Kelantan soil series, CEC was strongly correlated with total and medium-term plant-available S. Our results indicates that the influence of flooding conditions on soil S and Mo contents in paddy fields may cause long-term changes in S and Mo chemical reactivities. 相似文献
57.
The demand for cloud computing is increasing dramatically due to the high computational requirements of business, social, web and scientific applications. Nowadays, applications and services are hosted on the cloud in order to reduce the costs of hardware, software and maintenance. To satisfy this high demand, the number of large-scale data centers has increased, which consumes a high volume of electrical power, has a negative impact on the environment, and comes with high operational costs. In this paper, we discuss many ongoing or implemented energy aware resource allocation techniques for cloud environments. We also present a comprehensive review on the different energy aware resource allocation and selection algorithms for virtual machines in the cloud. Finally, we come up with further research issues and challenges for future cloud environments. 相似文献
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Two DNA fingerprinting techniques, random amplified polymorphic DNA (RAPD) and inter-retrotransposon amplified polymorphism
(IRAP), were used to characterize somaclonal variants of banana. IRAP primers were designed on the basis of repetitive and
genome-wide dispersed long terminal repeat (LTR) retrotransposon families for assessing the somaclonal variation in 2Musa clones resistant and susceptible toFusarium oxysporum f. sp.cubense race 4. RAPD markers successfully detected genetic variation within and between individuals of the clones. IRAP makers amplified
either by a single primer or a combination of primers based on LTR orientation successfully amplified different retrotransposons
dispersed in theMusa genome and detected new events of insertions. RAPD markers proved more polymorphic than IRAP markers. Somaclonal variation
seems to be the result of numerous indels occurring genome-wide accompanied by the activation of retroelements, as a result
of stress caused by micropropagation. It is concluded that characterization of the somaclonal variants requires more than
one DNA marker system to detect variation in diverse components of the genome. 相似文献