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51.
RENATA JACH ELŻBIETA MACHANIEC ALFRED UCHMAN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(3):342-355
Jach, R., Machaniec, E. & Uchman, A. 2011: The trace fossil Nummipera eocenica from the Tatra Mountains, Poland: morphology and palaeoenvironmental implications. Lethaia, Vol. 45, pp. 342–355. The tubular trace fossil Nummipera eocenica Hölder 1989 occurs in a single stratigraphical horizon in Eocene nummulitic limestones of the Tatra Mountains, Poland. The wall of N. eocenica is built of Discocyclina and Nummulities (larger foraminifera) tests, very rarely of the Ditrupa (Polychaeta) tube fragments, bivalve shell fragments, echinoid spines and coralline algae. Morphotype are distinguished on the basis of wall composition and structure. Morphotype A is dominated by fusiform Discocyclina tests, which were preferentially selected by the trace makers for construction of a well‐constructed and resistant wall. Morphotype B contains more robust tests of Nummulites, while morphotype C is dominated by saddle‐shaped tests of Discocyclina. Nummipera eocenica was produced during a period of seafloor stabilization caused by a deepening. The succession of the morphotypes B, A reflects diminishing energy and increasing water depth. Probably morphotype C represents even lower energy environment than morphotype A. The trace fossil is interpreted as a domichnion, which wall was constructed for protection. The trace maker can be considered between polychaetes and crustaceans; however, comparisons to the closest recent analogues, the polychaete Diopatra cuprea or alpheid shrimps, are not satisfactory. □Bartonian, burrow, Carpathians, large foraminifera, trace fossils. 相似文献
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D. VERDAGUER X. ARANDA A. JOFRÉ B. EL OMARI M. MOLINAS & I. FLECK 《Plant, cell & environment》2003,26(8):1407-1417
The total antioxidant activity (TAA) and the accumulation of small heat shock proteins (sHsps) were analysed under field conditions in Quercus ilex with regard to organ ontogeny and the physiological state of the plant. The results point toward the participation of sHsps and an increase of TAA in the general adaptation syndrome (GAS) of woody Mediterranean evergreens. In leaves and stems, there was a definite TAA seasonal pattern but no effect from diurnal variations or from the current stage of organ ontogeny. TAA was about twice as large in summer as in spring and winter and the hydrophilic antioxidant content was about 16 times greater than that of lipophilic antioxidants. The accumulation of sHsps in leaves also showed a seasonal pattern, but no effect from diurnal variations or from leaf ontogeny. In summer days, the sHsps content remained invariable even during the daylight hours in which the leaves were physiologically recovered. However, the accumulation of sHsps in stems did vary in relation to organ ontogeny. Old stems had a high accumulation of sHsps throughout the year, whereas in young stems, accumulation of sHsps was detected only in summer. This is probably due to a higher quantity of lignified and suberized tissues in the older stems. Using two‐dimensional immunodetection for leaves and stems, two sets of Hs protein species (17 and 10 kDa regions) were observed. In stems, there was an increase in 10 kDa proteins from winter to summer. These results are discussed and the possible role of the two types of polypeptides in the face of environmental and endogenous oxidative stress are considered. 相似文献
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D. Jabborova R.Z. Sayyed A. Azimov Z. Jabbarov A. Matchanov Y. Enakiev Alaa Baazeem Ayman EL Sabagh Subhan Danish Rahul Datta 《Saudi Journal of Biological Sciences》2021,28(9):5268-5274
Ginger is used as one of the important ingredients in traditional as well as modern medicine besides as a spice. It boosts immunity and is a rich source of many biologically active substances and minerals. Although it is a medicinally important crop, its productivity is, however, affected due to poor nutrient management and therefore it requires an adequate supply of nutrients in the form of inorganic fertilizers or organic manuring, or a mixture of both. In this context, the present study was aimed to investigate the effect of mineral fertilizers on the content of mineral elements in the ginger rhizome, on soil enzyme activity, and soil properties. Lysimeter experiments were conducted at the Institute of Genetics and Plant Experimental Biology, Kibray, Tashkent region, Uzbekistan. The experiment comprised of four treatments T1 – Control, T2 - N75P50K50 kg/ha, T3 - and T4 - N100P75K75 + B3Zn6Fe6 kg/ha. The results showed that the application of N125P100K100 kg/ha increased rhizome K content by 49%, P content by 20%, and Na content by 58% as compared to control without fertilizer. While the application of N100P75K75 + B3Zn6Fe6 kg/ha showed a significant enhancement in rhizome K, Ca, P, Mg, Na, Fe, Mn, Zn, Cu, Cr, Mo, and Si contents over the control. This treatment also improved active P content by 29%, total P content by 80%, total K content 16%, and N content by 33% content, and the activities of urease, invertase, and catalase activities as compared to control of without mineral fertilizer and control respectively. Thus the application of NPK + BZnFe at the rate of 100:75:75:3:6:6 kg/ha helps in improving macroelements and microelements in the ginger rhizome and activities of soil enzymes that helps in mineral nutrition of the rhizome. 相似文献
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Sayed M. Riyadh Shojaa A. El‐Motairi Hany E. A. Ahmed Khaled D. Khalil EL‐Sayed E. Habib 《化学与生物多样性》2018,15(9)
2‐(1‐{4‐[(4‐Methylphenyl)sulfonamido]phenyl}ethylidene)thiosemicarbazide ( 3 ) was exploited as a starting material for the synthesis of two novel series of 5‐arylazo‐2‐hydrazonothiazoles 6a – 6j and 2‐hydrazono[1,3,4]thiadiazoles 10a – 10d , incorporating sulfonamide group, through its reactions with appropriate hydrazonoyl halides. The structures of the newly synthesized products were confirmed by spectral and elemental analyses. Also, the antimicrobial, anticancer, and DHFR inhibition potency for two series of thiazoles and [1,3,4]thiadiazoles were evaluated and explained by molecular docking studies and SAR analysis. 相似文献
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Polly J Phillips-Mason Sonya EL Craig Susann M Brady-Kalnay 《Cell Adhesion & Migration》2011,5(4):298-305
Dissolution of cell-cell adhesive contacts and increased cell-extracellular matrix adhesion are hallmarks of the migratory and invasive phenotype of cancer cells. These changes are facilitated by growth factor binding to receptor protein tyrosine kinases (RTKs). In normal cells, cell-cell adhesion molecules (CAMs), including some receptor protein tyrosine phosphatases (RPTPs), antagonize RTK signaling by promoting adhesion over migration. In cancer, RTK signaling is constitutive due to mutated or amplified RTKs, which leads to growth factor independence or autonomy. An alternative route for a tumor cell to achieve autonomy is to inactivate cell-cell CAMs such as RPTPs. RPTPs directly mediate cell adhesion and regulate both cadherin-dependent adhesion and signaling. In addition, RPTPs antagonize RTK signaling by dephosphorylating molecules activated following ligand binding. Both RPTPs and cadherins are downregulated in tumor cells by cleavage at the cell surface. This results in shedding of the extracellular, adhesive segment and displacement of the intracellular segment, altering its subcellular localization and access to substrates or binding partners. In this commentary we discuss the signals that are altered following RPTP and cadherin cleavage to promote cell migration. Tumor cells both step on the gas (RTKs) and disconnect the brakes (RPTPs and cadherins) during their invasive and metastatic journey.Key words: receptor protein tyrosine kinase, receptor-like protein tyrosine phosphatase, cadherins, cell adhesion, signal transduction, phospholipase C gamma, protein kinase C, catenins, IQGAP1 protein, regulated intramembrane proteolysis 相似文献
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Crown-gall tumor initiation by Agrobacterium tumefaciens (SMITHand TOWN.) CONN, strain B6, on Phaseolus vulgaris L. var. "Pinto"was found to be sensitive to the addition of various salts tothe freshly inoculated primary leaves. Calcium, magnesium, zincand ammonium sulfates, cobalt and nickel chlorides and potassiumnitrate increased the number of tumors on inoculated leavesby 100 to 200 percent. Maximal promotions were obtained at concentrationsof 107 to 105 M with all of these salts exceptpotassium nitrate which was most active at 102M. Sodium,potassium, calcium, magnesium and aluminum chlorides, and sodium,potassium and nickel sulfates had little or no effect on tumorinitiation. The combination of sodium sulfate with magnesiumchloride gave promotions comparable to those obtained with magnesiumsulfate, indicating that both the magnesium and sulfate ionswere necessary for the promotion obtained with this latter salt.Combining any two of the active salts at their optimum concentrationsfor promotion resulted in a reciprocal inhibition of the promotionobtained with either salt alone, suggesting these salts to beactive by different and potentially antagonistic mechanisms.The possible nature of these promotions is discussed, but theyremain too obscure to warrant a specific proposal for theirmode of action.
1Present adress: Department of Botany, University of Khartoum,Khartoum, Sudan. 相似文献