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1.
Solid-phase extraction method was developed for the preconcentration of thorium (Th). Fungal biomass Agaricus bisporus was immobilized to Amberlite XAD-4 as solid-phase sorbent. The critical parameters such as pH of the sample solution, flow rate of the sample, volume of the sample, and the effect of major ions that affect the preconcentration of thorium in this system were evaluated. The optimum pH for the sorption of Th is 6.0, and quantitative elution occurs with 1.0 mol L?1HCl. The loading capacity was determined as 0.079 mmol g?1. The optimized method was validated through analysis of the certified reference material of tea leaves (NCS ZC73014) and successfully applied to the determination of Th in a real ore sample with satisfactory results. 相似文献
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Silan F Gultekin Y Atik S Kilinc D Alan C Yildiz F Uludag A Ozdemir O 《Molecular biology reports》2012,39(2):1595-1599
Prostate cancer is a common malignancy that develops by structural mutation(s) and/or other genetic alterations in specific
genes.The G to T transversions in codon 12 and C to T transitions in codon 13 of KRAS proto-oncogene are predominant point
mutations that occur in about 20% of different cancers in human. In the current study it was aimed to investigate the prevalence
and predictive significance of KRAS mutations in patients with prostate carcinomas. In a total of 30 fresh tumoural tissue
specimens were investigated in patients with prostate carcinoma. All tumoural specimens were histo-pathologically diagnosed
and genotyped for codon 12, 13 KRAS point mutations by reverse hybridisation and direct sequencing methods. KRAS mutations
were found in 12 (40%) samples with 29 samples deriving from adenocarcinomas and 1 sample was small cell prostate carcinoma.
In 1 (3.44%) sample codon 12 was found to be mutated and in 2 (6.8%) samples codon 13 and in 9 (31%) samples combined codon
12 and 13 were found to be mutated particularly in higher grade of tumoural tissues. Our study, based on representative collection
of human prostate tumours, indicates that combined mutations in codons 12 and 13 KRAS are relatively infrequent and most commonly
occur in prostate carcinomas. 相似文献
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Şahin Burcu Öztürk Sibel Çalık Pınar Özdamar Tunçer H. 《Bioprocess and biosystems engineering》2015,38(10):1855-1865
Bioprocess and Biosystems Engineering - Defined and semi-defined medium-based feeding strategies were developed to enhance recombinant human growth hormone (rhGH) production by Bacillus subtilis... 相似文献
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Elif Varhan Oral Sadin Ozdemir Ibrahim Dolak Veysi Okumus Abdurrahman Dundar Berrin Ziyadanogullari 《Bioremediation Journal》2015,19(2):139-150
A new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1–immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0 ml of 1.0 mol L?1 HCI and 10.0 ml of 0.25 mol L?1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 ± 1.57% and 100.3 ± 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3 s, N = 10) were found to be 0.8 and 1.6 μg L?1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbak?r and Elaz??, Lake of Hazar in Elaz??, and tap water in Diyarbak?r. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar). 相似文献
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The pathogenic fungus Aspergillus alliaceus has been shown to have potential for the biocontrol of Orobanche spp. (broomrape), a root parasitic plant. The effectiveness of A. alliaceus in reducing Orobanche infection was analysed using pesta granules prepared with different food formulations. The results showed that pesta granules comprising of fungal mycelia/spore mixtures from liquid and solid culture, sclerotia and fungal mycelia reduced Orobanche infection to a greater extent in below ground conditions when applied early and at high doses before crop sowing. In addition, pesta granules eliminated the risk of broomrape contamination within a 0.2–0.3 cm diameter of the granules. The sclerotial pathogenicity of A. alliaceus was compared with those of other fungi reported in other studies. In addition, some morphological and histological studies on the fungal pathogenicity on broomrape plants after infection are presented. The present study reveals the potential of sclerotial A. alliaceus pesta granule applications for long-term broomrape biocontrol under field conditions. 相似文献
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Nisin production of Lactococcus lactis N8 with hemin‐stimulated cell respiration in fed‐batch fermentation system 下载免费PDF全文
In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed‐batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed‐batch fermentation system with high fidelity (R2 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L?1 h?1, 3 μg mL?1 and 40%, respectively. While 1711 IU mL?1 nisin was produced by L. lactis N8 in control fed‐batch fermentation, 5410 IU mL?1 nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed‐batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed‐batch fermentation. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:678–685, 2015 相似文献
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Ozt��rk Ozdemir Ilhan Sezgin Hande Kucuk Kurtulgan Ferhan Candan Binnur Koksal Haldun Sumer Dilara Icagasioglu Atilla Uslu Fazilet Yildiz Sulhattin Arslan Selma Cetinkaya Senol Citli Zekeriya Oztemur Mansur Kayatas 《Molecular biology reports》2011,38(5):3195-3200
The Familial Mediterranean Fever (FMF) shows an autosomal recessive pattern of inheritance and affects certain ethnic groups. Disease is caused by mutations in MEFV gene and more than 180 mutations have been defined in affected individuals. Current study aimed to determine the frequency-type of the mutations for MEFV gene in Sivas??middle Anatolian city. The cohort was composed of 3340 patients. MEFV gene mutations were studied by multiplex PCR based reverse hybridization stripAssay method. Patients?? clinical features were; family history: 68%, erysipelas-like erythema: 17.6%, fever: 89.9%, abdominal pain: 84.2%, peritonitis: 90.2%, arthritis: 33%, pleuritis: 14.2%, parental consanguinity: 21.2%. Current results revealed that M694V is the most frequent mutation (43.12%), followed by E148Q (20.18), M680I(G/C) (15.00%) and V726A (11.32%). The study population has a high rate of carriers and the E148Q mutation frequency was found to be highest when compared to the other regions of Turkey and other Mediterranean groups. 相似文献