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711.
Masa-oki Yamada Takeshi Minami Masayo Ichii Yuko Okazaki Masako Utsumi Setsuko Tohno Yoshiyuki Tohno 《Biological trace element research》1996,52(2):155-161
Trace element analysis in excavated bones is complicated by the lack of a reliable index for estimating the original amount
of bone material. In this study, we subjected modern human bones to alkali treatment to simulate aging. Alkali treatment of
vertebrae with attached muscle did not affect sulfur (S) content; it increased the magnesium (Mg), phosphorus (P), and zinc
(Zn) contents, and tended to decrease iron (Fe) content of the bones. When vertebrae cleaned of muscle were used, alkali treatment
did not affect S and Fe contents but increased Mg, P, Ca, and Zn contents Ca and S contents were higher in excavated bones
(200–1300 yr old) than in their surrounding soils. In contrast, S, Mg, and Ca contents per dry weight did not differ between
the excavated bones and the alkali-treated modern bones. These results indicate that S can provide a more accurate index of
excavated bones than the often-used Ca content or dry wt measures, especially for bones excavated from calcium-rich soils. 相似文献
712.
The effects of 5 alpha-dihydrotestosterone (DHT) and thyroxine (T4) on glucose-6-phosphate dehydrogenase (G-6-PDH) activity in mouse submandibular gland were investigated histochemically. A strong positive histochemical reaction for G-6-PDH was observed in the excretory ducts of untreated male and female mice, with a slight reaction in the basal portion of the convoluted tubules (striated ducts) of males. Administration of DHT to female mice increased G-6-PDH activity specifically in the convoluted tubules. T4 increased the enzyme activity in the tubules more than DHT. The induction of G-6-PDH activity by T4 in adrenalectomized mice suggests that T4 has a direct effect on the submandibular gland. 相似文献
713.
Limnology - Cyanobacteria are the major producers of the taste and odour compounds geosmin and 2-methylisoborneol (2-MIB) in drinking water and fish worldwide. In recent years, the outbreaks of... 相似文献
714.
Takeshi Minami Kouji Hashii Ichiro Tateyama Eizi Kadota Yoshiyuki Tohno Setsuko Tohno Masako Utsumi Masa-Oki Yamada Masayo Ichii Kiyohiro Namikawa Yuko Okazaki 《Biological trace element research》1994,42(3):253-257
Platinum was determined by the inductively coupled plasma mass spectrometry (ICP-MS) in the intervertebral discs and vertebrae of ovarian tumor bearing patients treated withcis-diamminedichloro-platinum (II) (cisplatin). Platinum was 0.05 ng/mL at the absolute detection limit, and platinum was undetectable in the intervertebral discs and vertebrae of human specimens without cisplatin treatments. On the other hand, platinum was detected in the intervertebral discs and vertebrae of patients administered cisplatin, and platinum concentration was at levels of 1.06–10.31 μg/g dry tissue in the intervertebral discs and 0.60–1.28 μg/g dry tissue in the vertebrae, respectively. The platinum level of intervertebral discs was 4.3-fold higher than that of the vertebrae. Thus, platinum accumulates greatly in the intervertebral discs and somewhat in the vertebrae after administering cisplatin to patients for therapy. 相似文献
715.
S Okada M Yabuki T Kanno K Hamazaki T Yoshioka T Yasuda A A Horton K Utsumi 《Cell structure and function》1999,24(3):161-168
Geranylgeranylacetone (GGA) induces apoptosis in human leukemia HL-60 cells in a dose- and time-dependent manner. This effect was completely prevented by the pan-caspase inhibitor z-Val-Ala-Asp(OMe) fluoromethylketone, thereby implicating the caspase cascade in the process. Prior to DNA fragmentation, GGA treatment markedly activated caspase-3(-like) proteases, which might be responsible for the observed apoptosis. In addition, GGA treatment interfered with the processing and membrane localization of Rap1 and Ras, and these changes may be a result of apoptosis. Moreover, nitric oxide donors significantly accentuated the GGA-induced apoptosis, suggesting that the apoptotic pathway induced by GGA might be regulated by a redox-sensitive mechanism. Taken together, these data suggest that the isoprenoid, GGA, is an effective inducer of apoptotic cell death in HL-60 cells. 相似文献
716.
717.
Yuki Yoshimura Reina Hirayama Natsuko Miura Ryotaro Utsumi Kouichi Kuroda Mitsuyoshi Ueda Michihiko Kataoka 《Cell biology international》2021,45(8):1776-1783
At normal oxygen concentration, glycolytic enzymes are scattered in the cytoplasm of Saccharomyces cerevisiae. Under hypoxia, however, most of these enzymes, including enolase, pyruvate kinase, and phosphoglycerate mutase, spatially reorganize to form cytoplasmic foci. We tested various small-scale hypoxic culture systems and showed that enolase foci formation occurs in all the systems tested, including in liquid and on solid media. Notably, a small-scale hypoxic culture in a bench-top multi-gas incubator enabled the regulation of oxygen concentration in the media and faster foci formation. Here, we demonstrate that the foci formation of enolase starts within few hours after changing the oxygen concentration to 1% in a small-scale cultivation system. The order of foci formation by each enzyme is tightly regulated, and of the three enzymes, enolase was the fastest to respond to hypoxia. We further tested the use of the small-scale cultivation method to screen reagents that can control the spatial reorganization of enzymes under hypoxia. An AMPK inhibitor, dorsomorphin, was found to delay formation of the foci in all three glycolytic enzymes tested. These methods and results provide efficient ways to investigate the spatial reorganization of proteins under hypoxia to form a multienzyme assembly, the META body, thereby contributing to understanding and utilizing natural systems to control cellular metabolism via the spatial reorganization of enzymes. 相似文献
718.
Marcos Ryotaro Hara Alberto Jos Cavalheiro Pedro Gnaspini Deborah Y.A.C. Santos 《Biochemical Systematics and Ecology》2005,33(12):1210-1225
The arachnids of the order Opiliones (harvestmen) produce substances used in defense. In the present paper, we analyzed 22 species of Gonyleptidae to explore the use of defensive substances in taxonomy and evolutionary biology. Thirty-seven different compounds were detected, 18 of which were preliminarily identified. These compounds were mapped onto a phylogenetic tree showing the relationships within the Gonyleptidae. Data from Cosmetidae were used as an outgroup. Five ketones and six alkyl phenols were reported for the first time in harvestmen. 相似文献
719.
Further studies are described with a radiation-sensitive clone of V79 Chinese hamster cells, designated V79-AL162/S-10. Extended postirradiation treatment with caffeine causes V79-AL162/S-10 cells to respond like repair-competent V79 cells, but both kinds of cells suffer enhanced killing by caffeine, in a similar fashion, when the postirradiation treatment period is relatively brief. Extended postirradiation treatment of repair-competent cells causes them to respond like sensitive cells without caffeine post-treatment. Treating irradiated V79-AL162/S-10 cells with hypertonic saline appreciably reduces the survival rescue which can be effected by caffeine. This latter observation leads to the inference that the sectors of damage affected by anisotonic shock and caffeine post-treatment overlap. From these and other results we propose that the DNA replicational machinery of the cell is the locus of action of these radiation damage/repair processes. 相似文献
720.
Teiko Yamashita Jun-ichiro Murayama Hideo Utsumi Akira Hamada 《Biochimica et Biophysica Acta (BBA)/General Subjects》1985,839(1):26-31
Dog glycophorin, the major sialoglycoprotein of dog erythrocyte membranes, contains either N-acetyl- or N-glycolylneuraminic acid, depending upon the strain of dog. Glycolipids also contained the same sialic acid as those found in glycophorin when both materials are prepared from erythrocyte membranes of individual dogs. The O-glycosidic oligosaccharides were released from glycophorin, prepared from individual dogs, by alkaline borohydride treatment, and purified by gel filtration and ion-exchange chromatography. The structures of the reduced oligosaccharides were determined by methylation analysis and gas-liquid chromatography-mass spectrometry. The O-glycosidic oligoscharides identified were one tetrasaccharide - Neu5Ac(2→3)Gal)1→3)[Neu5Ac(2→6)[GalNAcol - two trisaccharides - Neu5Ac(2→3)Gal1→3)GaINAcol and Gal(1→3)[Neu5Ac(2→6)]GalNAcol. 相似文献