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101.
Mohammadhossein Esnaashary Mohammadhossein Fathi Mahdi Ahmadian 《Biotechnology letters》2014,36(6):1343-1347
The effect of the fluorine content and nano-structure of fluoridated hydroxyapatite (FHA) on human osteoblast-like (HO) cell behavior were investigated. FHA nanopowders and bulk nanostructured FHA, produced via mechanical alloying and two-step sintering, respectively, were used. The cytotoxicity of FHA nanopowders was assessed by MTT. Cell attachment to the surface of the bulk nanostructured FHA was evaluated by culturing of HO cells. Although HO cells proliferated 10 % more in contact with FHA nanopowders compared to culture medium without FHA nanopowders, an increase in the fluorine content of FHA caused a delay in the cell proliferation by about 2 days. Cell attachment on the bulk nanostructured FHA did not change the fluorine content. 相似文献
102.
Chellapandian Balachandran Alagumalai Vishali Natarajan Arun Nagendran Kathirvelu Baskar Abeer Hashem Elsayed Fathi Abd_Allah 《Saudi Journal of Biological Sciences》2021,28(8):4263-4269
Marine microbes are potential source for novel metabolites. They are efficient in producing these metabolites utilizing agrowastes. Protease is one of the enzymes which find wide industrial applications. In the present study, protease producing bacteria was isolated from marine sediments and the organism was identified as Bacillus halodurans. The organism was subjected to protease production under solid state fermentation (SSF) using different agrowastes as substrates. Among the substrates used, wheat bran yielded maximum quantity of protease. The fermentation process was carried out under different cultural conditions to optimize the parameters influencing the enzyme production. The results of the stain removal studies by the enzyme revealed the increased efficiency of the microbial enzyme than the commercial detergent. 相似文献
103.
Arbuscular mycorrhizal fungi regulate the oxidative system,hormones and ionic equilibrium to trigger salt stress tolerance in Cucumis sativus L. 总被引:1,自引:0,他引:1
Abeer Hashem Abdulaziz A. Alqarawi Ramalingam Radhakrishnan Al-Bandari Fahad Al-Arjani Horiah Abdulaziz Aldehaish Dilfuza Egamberdieva Elsayed Fathi Abd_Allah 《Saudi Journal of Biological Sciences》2018,25(6):1102-1114
Arbuscular mycorrhizal fungi (AMF) association increases plant stress tolerance. This study aimed to determine the mitigation effect of AMF on the growth and metabolic changes of cucumbers under adverse impact of salt stress. Salinity reduced the water content and synthesis of pigments. However, AMF inoculation ameliorated negative effects by enhancing the biomass, synthesis of pigments, activity of antioxidant enzymes, including superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase, and the content of ascorbic acid, which might be the result of lower level lipid peroxidation and electrolyte leakage. An accumulation of phenols and proline in AMF-inoculated plants also mediated the elimination of superoxide radicals. In addition, jasmonic acid, salicylic acid and several important mineral elements (K, Ca, Mg, Zn, Fe, Mn and Cu) were enhanced with significant reductions in the uptake of deleterious ions like Na+. These results suggested that AMF can protect cucumber growth from salt stress. 相似文献
104.
Nida Idrees B. Tabassum Elsayed Fathi Abd_Allah Abeer Hashem Robeena Sarah Mohammad Hashim 《Saudi Journal of Biological Sciences》2018,25(7):1365-1368
Water is considered a vital resource because it is necessary for all aspects of human and ecosystem survival. However, due to natural processes and anthropogenic activities, various pollutants have been added to the ground water system. Among these, heavy metals are some of the most serious pollutants. Cd, a toxic heavy metal used in Ni-Cd batteries, the colouration of plastic and various discarded electronic products released into the water system causes serious health issues. The chronic exposure to Cd produces a wide variety of acute and chronic effects in humans. Cd accumulates in the human body, especially in the kidneys, resulting in kidney damage (renal tubular damage), which is a critical health effect. Other effects of Cd exposure are disturbances in calcium metabolism, hypercalciuria and the formation of kidney stones. High exposure to Cd can lead to lung cancer and prostate cancer; hence, poor quality water that may result in Cd toxicity has become a global concern. Thus, the aim of this study is to determine the concentration of Cd in underground water sources in western U.P. regions. Water samples were acidified to 1% with nitric acid and then stored in double-capped polyethylene bottles for further analysis by an atomic absorption spectrophotometer. After comparing the data to the WHO (2011) permissible limit, the study revealed that the concentration of Cd was higher than the regulatory threshold; therefore, the underground water system is seriously affected by Cd toxicity. 相似文献
105.
Rahila Amber Muhammad Adnan Akash Tariq Shahid Niaz Khan Sakina Mussarat Abeer Hashem Asma A. Al-huqail Al-Bandari Fahad Al-Arjani Elsayed Fathi Abd_Allah 《Saudi Journal of Biological Sciences》2018,25(1):154-161
The present study aimed to investigate the efficacy of traditionally used anti-mastitis plants (Allium sativum, Bunium persicum, Oryza sativa and Triticum aestivum) in northwest Pakistan against bacterial pathogens. Selected plants were phytochemically screened for Alkaloids, Flavonoids, and Saponins and checked for in vitro antibacterial activity at concentration of 50 mg/ml against S. aureus, E. coli and K. pneumoniae by agar well diffusion method. Minimum inhibitory concentration and minimum bactericidal concentration was determined against multidrug resistant bacteria using tube dilution method. All extracts were found to significantly inhibit (p < 0.01, p < 0.05) the activity against bacterial strains examined. Among phytochemicals, alkaloids of all tested antimastitis plants produced significantly higher inhibition zones against bacteria. The minimum inhibitory concentration and minimum bactericidal concentration of phytochemicals and crude methanolic extracts against tested bacterial strains ranged between 12.5–50 mg/ml and 25–50 mg/ml, respectively. Medicinal plants traditionally used against mastitis are therapeutically active against bacterial pathogens. A. sativum and B. persicum were found to be potential candidate species for the development of novel veterinary drugs with low cost and fewer side effects. 相似文献
106.
In this study two carbohydrate biopolymers were used to entrap vitamin D3. In order to optimize the microencapsulation parameters, response surface methodology was applied to evaluate the effects of three independent variables (alginate percentage, vitamin: alginate weight ratio, and ultrasound time) on the efficiency of microencapsulation and loading capacity. According to the results, 0.23% alginate (W/V), 1: 5 weight ratio of vitamin D3: alginate, and 13.7 min ultrasound time were determined as the optimal conditions for obtaining maximum microencapsulation efficiency (92.86%) and loading capacity (30.1%). Then, the optimized carrier was coated by chitosan followed by the examinations of morphological characteristics, mean particle size, Fourier transform infrared (FTIR) spectrometry, in vitro release characteristics, and release modeling. Scanning electron microscopy examinations showed that the alginate and alginate-chitosan microcapsules had irregular and interlacing forms. The average particle sizes of alginate and alginate-chitosan were 11.3 and 23.3, respectively, which decreased to 9.8 and 14.0 μm after drying. Results of FTIR indicated a physical interaction between alginate and vitamin D3. The Weibull II model was found to be the best one to predict vitamin release behavior. The results of this study showed the potential application of developed carriers to encapsulate hydrophobic compounds. 相似文献
107.
Elsayed Fathi Abd_Allah Abdulaziz A. Alqarawi Abeer Hashem Ramalingam Radhakrishnan Asma A. Al-Huqail Fatma Olyan Naser Al-Otibi 《Journal of Plant Interactions》2018,13(1):37-44
Plant growth-promoting endophytic bacteria can stimulate the growth, nutrient acquisition, symbiotic performance and stress tolerance of chickpea plants under saline soil conditions. The aim of this study was to investigate the stress-adaptive mechanisms of chickpea plants mediated by Bacillus subtilis (BERA 71) under saline conditions. Inoculation with BERA 71 enhanced plant biomass and the synthesis of photosynthetic pigments and reduced the levels of reactive oxygen species (ROS) and lipid peroxidation in plants under conditions of stress. Furthermore, the activities of ROS-scavenging antioxidant enzymes (superoxide dismutase, peroxidase, catalase and glutathione reductase), the levels of non-enzymatic antioxidants (ascorbic acid and glutathione) and the total phenol content were increased in stressed plants during bacterial association. The bacteria decreased sodium accumulation and enhanced the nitrogen, potassium, calcium and magnesium content in the plants. The suppression of ROS generation and of lipid peroxidation and the accumulation of proline in BERA-71-inoculated plants enhanced the membrane stability under salinity stress and non-stress conditions. 相似文献
108.
Liam Chung Erik Thiele Orberg Abby L. Geis June L. Chan Kai Fu Christina E. DeStefano Shields Christine M. Dejea Payam Fathi Jie Chen Benjamin B. Finard Ada J. Tam Florencia McAllister Hongni Fan Xinqun Wu Sudipto Ganguly Andriana Lebid Paul Metz Sara W. Van Meerbeke Franck Housseau 《Cell host & microbe》2018,23(3):421
109.
Biological Trace Element Research - Unlike the role of mesenchymal stem cells (MSCs) in regenerative medicine, their application in cell therapy can be complicated by factors such as a reduction in... 相似文献
110.