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91.
Emine Çìl 《Journal of biological education》2016,50(4):366-383
Plants are an integral part of nature. Many plant species in almost any part of the world are under serious threats due to various reasons such as deforestation, pollution–of air, water and soil–caused by industrialisation, overgrazing and rapid population growth. It is likely that people have strong positive attitudes towards conservation of plants. This study investigated the effectiveness of an instructional approach based on integration of botany with chemistry and art on students’ attitude towards plants. This study was carried out in a science summer school for 10–12-years-old students (N = 49) in Turkey. The Plant Attitude Questionnaire was used as pre-test and post-test to assess the effects of the instruction on the students’ attitudes towards plants. Moreover, the participating children were asked to keep journals throughout the instruction. The children’s journals served as a data collection tool. The findings of the study indicated that integration of botany with chemistry and art is a good way to support children’s positive attitudes towards plants, particularly for an instructional approach based on the integration of plants with various disciplines to support children’s interest and enjoyment of plants. Also, this approach could offer children opportunities to understand the importance of plants in the living environments of humans and other organisms, and material benefits from plants in industry. 相似文献
92.
Hulya Gocer Abdulselam Aslan Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2016,31(3):503-507
This study explores the correlation between human carbonic anhydrase (CA, EC 4.2.1.1) isoforms I and II (hCA I, II) and the inhibitory features of some spirobisnaphthalene derivatives. A group of spirobisnaphthalenes was synthesized and their hCA I and II inhibitory effects was investigated. The Ki values were similar for both CA isoenzymes, the compounds showing good inhibitory activity. Ki values ranged between 1.60 and 460.42?µM for hCA I and between 0.39 and 419.42?µM for hCA II, respectively. The spirobisnaphthalenes derivatives might be useful for designing CA inhibitors belonging to novel chemotypes compared to the highly investigated sulfonamides, sulfamates or coumarins. 相似文献
93.
Emine Anayol Allah Bakhsh Ömer Cem Karakoç Selma Onarıcı Deniz Köm Muhammad Aasim Sancar Fatih Özcan Surendra Barpete Saber D. Khabbazi Burak Önol Cengiz Sancak Khalid M. Khawar Levent Ünlü Sebahattin Özcan 《Plant biotechnology reports》2016,10(2):83-94
Most of the commercialized Bt crops express cry genes under 35S promoter that induces strong gene expression in all plant parts. However, targeted foreign gene expression in plants is esteemed more important as public may be likely to accept ‘less intrusive’ expression of transgene. We developed plant expression constructs harboring cry1Ac gene under control of wound-inducible promoter (AoPR1) to confine Bt gene expression in insect wounding parts of the plants in comparison with cry1Ac gene under the control of 35S promoter. The constructs were used to transform four Turkish cotton cultivars (GSN-12, STN-468, Ozbek-100 and Ayhan-107) through Agrobacterium tumefaciens strains GV2260 containing binary vectors p35SAcBAR.101 and AoPR1AcBAR.101 harboring cry1Ac gene under control of 35S and AoPR1, respectively. Phosphinothricin (PPT) was used at concentration of 5 mg L?1 for selection of primary transformants. The primary transformants were analyzed for transgene presence and expression standard molecular techniques. The transformants exhibited appreciable mortality rates against larvae of Spodoptera exigua and S. littoralis. It was found that mechanical wounding of T 1 transgenic plants was effective in inducing expression of cry1Ac protein as accumulated levels of cry1Ac protein increased during post-wounding period. We conclude that use of wound-inducible promoter to drive insecticidal gene(s) can be regarded as a valuable insect-resistant management strategy since the promoter activity is limited to insect biting sites of plant. There is no Bt toxin accumulation in unwounded plant organs, seed and crop residues, cotton products and by-products, thus minimizing food and environmental concerns. 相似文献
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96.
Arica MY Yalçin E Bayramoğlu G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,807(2):315-325
In this study, an affinity membrane containing L-histidine as an amino acid ligand was used in separation and purification of human immunoglobulin G (HIgG) from solution and human serum. The polarities and the surface free energies of the affinity membranes were determined by contact angle measurements. HIgG adsorption and purification onto the affinity membranes from aqueous solution and human serum were investigated in a batch and a continuous system. Effect of different system parameters such as ligand density, adsorbent dosage, pH, temperature, ionic strength and HIgG initial concentration on HIgG adsorption were investigated. The maximum adsorption capacity of p(HEMA-MAAH-4) membranes for HIgG was 13.06 mgml(-1). The reversible HIgG adsorption on the affinity membrane obeyed both the Langmuir and Freundlich isotherm models. The adsorption data was analysed using the first- and second-order kinetic model and the experimental data was well described by the first-order equations. In the continuous system, the purity of the eluted HIgG, as determined by HPLC, was 93% with recovery 58% for p(HEMA-MAAH-4) membrane. The affinity membranes are stable when subjected to sanitization with sodium hydroxide after repeated adsorption-elution cycles. 相似文献
97.
Birat Kanchan Siddiqi Tariq Omar Mir Showkat Rasool Aslan Junaid Bansal Rakhi Khan Washim Dewangan Rikeshwer Prasad Panda Bibhu Prasad 《International microbiology》2022,25(2):275-284
International Microbiology - Vincristine, one of the major vinca alkaloid of Catharanthus roseus (L.) G. Don. (Apocynaceae), was enhanced under in vitro callus culture of C. roseus using fungal... 相似文献
98.
Belma Turan Nezahat Zaloglu Emine Koc Yüksel Saran Nuri Akkas 《Biological trace element research》1997,58(3):237-253
The present study was designed to investigate and compare the effects of dietary selenium (Se) and vitamin E on some physiological parameters and histological changes in liver, heart, and skin tissues, as well as the blood parameters and the related enzymes. Both sex young rabbits were fed with deficient (9.8 μg/kg diet), adequate (225 μg/kg diet), and rich (4.2 mg/kg diet) Se and vitamin E diets for 12–15 wk for this purpose. As the plasma Se levels and the erythrocyte glutathione (GSH) peroxidase activity decreased (79.8±9.4 ng/ml and 2.0±0.3 U/g Hb, respectively) in the deficient group, these values increased (100.4±2.7 ng/mL and 14.5±4.3 U/g Hb) in the rich group significantly with respect to the control group. The other antioxidant enzyme activities and the related element levels did not change significantly in either one of the experimental groups. Although the platelet counts of the two experimental groups were not different from the control values, the collagen and the adenosine diphosphate (ADP) stimulated platelet aggregation rate and intensity increased in the deficient group (p<0.05) and decreased very significantly (p<0.001) in the rich group. In both of the experimental groups, as the percentage values of the neutrophils decreased, the lymphocytes and the eosinophils increased significantly. According to the light microscopic investigations, the observed lesions of considerable intensity within the tissues that elicit cell degenerations were more pronounced in the animals fed with the rich diet than in those fed with the deficient diet. The deficiency as well as toxicity of Se and the deficiency of vitamin E caused several alterations in the physiological functions of the tissues, and these alterations were supported by the histological lesions within these tissues. 相似文献
99.
P53 is a tumor suppressor gene and a critical component of cellular mechanisms that respond to genotoxic stresses. During
normal fetal development, some of these cells lose their genomic stability because of intensive cell proliferation. They arrest
cell cycle progression and repair genomic stability by p53 induction or die via apoptosis. If p53 is overexpressed, some structures
may have different abnormalities. This study was conducted to investigate normal p53 expression in human male gonads during
second trimester. Twenty one normal human male fetuses’ testes in 2nd trimester were processed and immunohistochemistry was
applied. The spermatogonia with nuclear and perinuclear staining, were accepted as p53 (+). The number of p53 (+) spermatogonia
was counted in randomly 10 different seminiferous tubules. The results suggest that p53 expression in gonads of human male
fetuses significantly increases in the 20th week. 相似文献
100.
Several lichen species have been used for medicinal purposes throughout the ages, and they are reported to be effective in the treatment of different disorders including ulcer and cancer. It is revealed that lichens may be easily accessible sources of natural drugs and possible food supplements after their safety evaluations. The main objective in this study was to evaluate the roles of aqueous extracts of Xanthoria elegans (at 25, 50 and 100 μg/ml) upon mitomycin C (MMC; at 10−7 M) induced genotoxic and oxidative damages in cultured human lymphocytes. X. elegans were collected from the Erzurum and Artvin provinces (in Turkey) during August 2010. After the application of MMC and X. elegans extract (XEE), separate and together, human whole blood cultures were assessed by four genotoxicity end-points including chromosomal aberration, micronucleus, sister chromatid exchange (SCE) and 8-oxo-2-deoxyguanosine (8-OH-dG) assays. In addition, biochemical parameters [total antioxidant capacity (TAC) and total oxidative stress (TOS)] were examined to determine oxidative effects. According to our results, the frequencies of cytogenetic endpoints and 8-OH-dG levels were significantly increased by MMC compared with controls in human peripheral lymphocytes. MMC caused oxidative stress by altering TAC and TOS levels. On the contrary, XEE led to increases of TAC level without changing TOS level. XEE had no genotoxic effect. Furthermore, our findings revealed that MMC induced increases in the mean frequencies of four genotoxic indices were diminished by XEE in dose dependent manner, indicating its protective role towards cells from MMC exerted injury. In conclusion, the results obtained in the present study indicate for the first time that XEE is a potential source of natural antigenotoxicants. 相似文献