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51.
The number and concentration of haemopoietic stem cells in the femoral bone marrow and spleen of Wistar rats of different ages were investigated. Stem cells were assayed by the spleen colony technique in irradiated rat recipients. The ability of the recipient spleen to harvest transplanted tissue as a macroscopic colony was found to be dependent on the recipient's age. Changes with senescence were observed also in the concentration and the size of the stem cell compartment both in the marrow and spleen. No differences were demonstrated in the seeding of transplanted colony-forming units into the spleen of recipients of 1 and 4 months of age. A rats-mice strain difference in the effect of senescence on the haemopoietic stem cells is discussed. 相似文献
52.
Deniz EKİNCİ 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):1034-1039
The in vitro effects of the analgesic drugs, lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine, on the activity of purified human serum paraoxonase (hPON1) (EC 3.1.8.1.) were evaluated. hPON1 was purified from human serum with a final specific activity of 3840 U mg?1 and a purity of 25.3 % using simple chromatographic methods, including DEAE-Sephadex anion exchange and Sepharose 4B-L-tyrozine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis indicated a single protein band corresponding to hPON1. The six analgesics dose-dependently decreased in vitro hPON1 activity, with IC50 values for lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine of 0.136, 0.195, 0.340, 1.639, 6.23 and 9.638 mM, respectively. Ki constants were 0.009, 0.097, 0.306, 0.805, 13.010 and 11.116 mM, respectively. Analgesics showed different inhibition mechanisms: lornoxicam, diclofenac sodium and lincomycine were uncompetitive, indomethacin and tenoxicam were competitive, ketoprofen was noncompetitive. According to the results, inhibition potency was lornoxicam>indomethacin>tenoxicam> diclofenac sodium>ketoprofen> lincomycine. 相似文献
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Commercial probiotic capsules that contain probiotic bacteria, kefir, koumiss and yogurt contain beneficial microorganisms that affect cholesterol levels and immune response, and are used for treatment of some diseases. We investigated using immunohistochemistry the effects of kefir, koumiss, yogurt and a commercial probiotic formulation on the expression levels of peroxisome proliferator-activated receptor-α (PPARα) and peroxisome proliferator-activated receptor-β/δ (PPAR-β/δ), which are members of the nuclear steroid hormone receptor superfamily in mouse kidney. Mice were assigned to five groups: group 1, commercial probiotic capsules; group 2, kefir; group 3, koumiss; group 4, yogurt; group 5, control. After oral administration for 15 days, body weights were recorded and kidney tissue samples were obtained. Hematoxylin & eosin staining and the streptavidin-biotin peroxidase complex (ABC) method were applied to tissue sections to examine histology and to determine the localization of PPARα and PPAR-β/δ in the kidneys. We found that the weights of the mice in the kefir, koumiss, yogurt and commercial probiotic capsules groups were increased compared to controls. No differences in kidney histology were observed in any of the experimental groups. Kefir, koumiss, yogurt and the commercial probiotic preparation increased PPARα and PPAR-β/δ expressions. 相似文献
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Spice EK Whitesel TA McFarlane CT Docker MF 《Genetics and molecular research : GMR》2011,10(4):3246-3250
The Pacific lamprey (Entosphenus tridentatus) is an anadromous fish that is of conservation concern in North America and Asia. Data on Pacific lamprey population structure are scarce and conflicting, impeding conservation efforts. We optimized 12 polymorphic microsatellite loci for the Pacific lamprey. Three to 13 alleles per locus were observed in a sample of 51 fish collected from the West Fork Illinois River, Oregon. Observed heterozygosity ranged from 0.235 to 0.902 and expected heterozygosity ranged from 0.214 to 0.750. Cross-species amplification produced 8 to 12 polymorphic loci in four other Entosphenus species and in the western brook lamprey (Lampetra richardsoni). Two loci appear to be diagnostic for distinguishing Entosphenus from Lampetra. These markers will be valuable for evaluating population structure and making conservation decisions for E. tridentatus and other lamprey species. 相似文献
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Endemic atyids of southern Europe have been ascribed to Dugastella, and to subterranean Typhlatya and Troglocaris: Dugastella is epigean, and Typhlatya and Troglocaris are subterranean. An extensive collection from all centres of distribution in southern Europe (excepting the Caucasus) was morphologically examined. A taxonomic redefinition of the group, at different levels, is based on recently published and newly generated molecular phylogeny, whereas newly established taxa have also been morphologically defined. The accordance between the phylogenetic tree and the geographical distributions suggested that a re‐evaluation of some traditionally used morphological characters should generate the most parsimonious solution: this enabled a novel taxonomic division. Gallocaris gen. nov. is erected for the French Troglocaris inermis Fage, 1937, which is more closely related to the epigean Dugastella valentina (Ferrer Galdiano, 1924) than to its supposed congeners. Both western Mediterranean Typhlatya species are closely related to their Caribbean congeners. All other European cave shrimps constitute a monophylum, Troglocaris, which is divisible into subgenera (already with available names): the holo‐Dinaric Troglocaris (Troglocaris) Dormitzer, 1853, south‐eastern mero‐Dinaric Troglocaris (Troglocaridella) Babi?, 1922, and Troglocaris (Spelaeocaris) Matja?i?, 1956, and the Caucasian Troglocaris (Xiphocaridinella) Sadovsky, 1930. Four new species are described: Troglocaris (Troglocaris) bosnica sp. nov. , Troglocaris (Spelaeocaris) prasence sp. nov. , Troglocaris (Spelaeocaris) kapelana sp. nov. , and Troglocaris (Spelaeocaris) neglecta sp. nov. The distribution of all established species is shown, and the value of the morphological characters is discussed. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 786–818. 相似文献
58.
CONSUELO SENDINO KAMIL ZÁGORŠEK PAUL D. TAYLOR 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(3):423-431
Sendino, C., Zágor?ek, K. & Taylor, P.D. 2012: Asymmetry in an Ordovician conulariid cnidarian. Lethaia, Vol. 45, pp. 423–431. Conulariids are fossils of the presumed polyps of an extinct scyphozoan cnidarian group. Their cone‐shaped skeletons normally show perfect tetraradial symmetry. However, in the Ordovician species Metaconularia anomala ( Barrande 1867 ) from Drabov (Czech Republic), tetraradial symmetry is compromised in three ways: (1) the skeleton often shows torsion; (2) the four sides may vary in width at the same level within one individual; and (3) one side may be deleted to give a triradial skeleton. Almost 2000 specimens were studied in museum collections. About 56% of analysed specimens are twisted in an anticlockwise direction (sinistral) when viewed from the apex towards the aperture, 28% show no torsion, 1% exhibit clockwise torsion (dextral) and the remaining 15% cannot be classified. Maximum measured torsion rate was 1.5°/mm. A significant negative correlation between torsion rate and length suggests that more highly torted individuals may have survived less well. Almost 5% of individuals show loss of one side for at least part of their lengths. Although many individuals have four sides of equal width, in a significant proportion the sides are of unequal width, up to a maximum/minimum side width ratio of 2 (i.e. widest face twice the width of the narrowest). In the absence of a satisfactory taphonomic model to explain the asymmetries, they are regarded as mirroring asymmetries in the living conulariids, with the strong preference for sinistral torsion interpreted as an example of a fixed asymmetry that was genetically controlled and heritable. It is speculated that the signalling protein Nodal as well as Hox‐like genes were involved in controlling the asymmetries described in M. anomala. 相似文献
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