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931.
M Tanaka T Setoguchi Y Ishidou Y Arishima M Hirotsu Y Saitoh S Nakamura H Kakoi S Nagano M Yokouchi J Kamizono S Komiya 《Diagnostic pathology》2012,7(1):108-5
ABSTRACT: We present a case of a 62-year-old man who underwent total hip arthroplasty for treatment of pathologic femoral neck fracture associated with adefovir dipivoxil-induced osteomalacia. He had a 13-month history of bone pain involving his shoulders, hips, and knee. He received adefovir dipivoxil for treatment of lamivudine-resistant hepatitis B virus infection for 5 years before the occurrence of femoral neck fracture. Orthopedic surgeons should be aware of osteomalacia and pathological hip fracture caused by drug-induced renal dysfunction, which results in Fanconi's syndrome.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1600344696739249. 相似文献
932.
Fei Jin Minxuan Sun Takashi Fujii Yurika Yamada Jin Wang Andrs D. Maturana Miki Wada Shichen Su Jinbiao Ma Hironori Takeda Tsukasa Kusakizako Atsuhiro Tomita Yoshiko Nakada-Nakura Kehong Liu Tomoko Uemura Yayoi Nomura Norimichi Nomura Koichi Ito Osamu Nureki Keiichi Namba So Iwata Ye Yu Motoyuki Hattori 《PLoS biology》2021,19(4)
MgtE is a Mg2+ channel conserved in organisms ranging from prokaryotes to eukaryotes, including humans, and plays an important role in Mg2+ homeostasis. The previously determined MgtE structures in the Mg2+-bound, closed-state, and structure-based functional analyses of MgtE revealed that the binding of Mg2+ ions to the MgtE cytoplasmic domain induces channel inactivation to maintain Mg2+ homeostasis. There are no structures of the transmembrane (TM) domain for MgtE in Mg2+-free conditions, and the pore-opening mechanism has thus remained unclear.Here, we determined the cryo-electron microscopy (cryo-EM) structure of the MgtE-Fab complex in the absence of Mg2+ ions. The Mg2+-free MgtE TM domain structure and its comparison with the Mg2+-bound, closed-state structure, together with functional analyses, showed the Mg2+-dependent pore opening of MgtE on the cytoplasmic side and revealed the kink motions of the TM2 and TM5 helices at the glycine residues, which are important for channel activity. Overall, our work provides structure-based mechanistic insights into the channel gating of MgtE.MgtE is a magnesium-selective ion channel whose gating is regulated by cytoplasmic magnesium concentration; this cryo-EM study reveals how MgtE undergoes magnesium-dependent structural changes to open the pore on the cytoplasmic side. 相似文献
933.
Hironori Ishizaki Akinori Suzuki Akira Isogai Hiromichi Nagasawa Saburo Tamura 《Journal of insect physiology》1977,23(10):1219-1222
The effects of various enzymatic and chemical treatments on the biological activity of the partially purified PTTH are described. PTTH was inactivated by pepsin, trypsin and α-chymotrypsin. Leucine aminopeptidase and carboxypeptidase A did not affect the biological activity of PTTH, suggesting that N- and C-terminus are blocked. Treatments with chemical reagents suggest that the tryptophan residue and disulfide bond are essential for the activity, whereas the sulfhydryl group is not. Tyrosinase exerted no effects. Glycosidases, neuraminidase, and periodate oxidation did not affect the activity, suggesting that carbohydrates are not essential for the biological activity of PTTH. 相似文献
934.
935.
Akira Mizoguchi Hironori Ishizaki 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1984,155(5):639-647
Summary Experiments using various light-dark (LD) conditions demonstrated that an endogenous circadian clock controls gut-purge timing in the saturniid mothSamia cynthia ricini. A phase-response curve (PRC) based on the application of brief (15 min) light pulses is used to characterize the underlying pacemaking oscillation. The entrainment of the pacemaker to various LD cycles is interpreted in terms of this PRC. The effect of light immediately preceding gut purge was analyzed to account for the deviation of the actual gut-purge rhythm from the prediction made by considering only the action of the oscillation. Lack of precision in gut-purge timing in LD cycles with a very short scotophase has been explained by the failure of the oscillation in these conditions to attain the specific phase-point at which the clock information dictating gut-purge timing is released.Abbreviations
AZT
arbitrary Zeitgeber time
-
CT
circadian time
-
PRC
phase response curve 相似文献
936.
The effect of prey behaviour on prey acquisition by a predator was examined in the laboratory, using three larval mosquitoes.Aedes albopictus was acquired by the predator,Toxorhynchites towadensis, at a higher rate thanOrthopodomiya anopheloides. Toxorphynchites towadensis was a sit-and-wait predator.Aedes albopictus was more active thanO. anopheloides. Orthopodomiya anopheloides ran away before the predator attacked, butA. albopictus did not. The escape ratio inO. anopheloides was higher than that inA. albopictus. These results suggest that the difference in the prey acquisition ratio by the predator between prey species is caused by
different behavioural patterns of the prey to the predator. 相似文献
937.
Abstract 1. The literature on ladybirds indicates that males are consistently smaller than females but take the same length of time to complete their development. Rearing Adalia bipunctata at 20 and 25 °C confirmed that protandry cannot account for sexual size dimorphism in this species, nor can a difference in egg size.
2. Female larvae consumed more food and had a higher relative growth rate in the fourth instar than did male larvae.
3. When food is limited, small males appear to be more successful at mating than are large males.
4. To account for these results, it is hypothesised that the gonads of male larvae compete more strongly with the soma for resources and that this reduces the growth potential of the soma of male larvae relative to that of female larvae. The greater mating success of small males when food is limited supports the eat or mate hypothesis, which predicts that when food is limited small males will spend less time feeding and more time mating than will large males. 相似文献
2. Female larvae consumed more food and had a higher relative growth rate in the fourth instar than did male larvae.
3. When food is limited, small males appear to be more successful at mating than are large males.
4. To account for these results, it is hypothesised that the gonads of male larvae compete more strongly with the soma for resources and that this reduces the growth potential of the soma of male larvae relative to that of female larvae. The greater mating success of small males when food is limited supports the eat or mate hypothesis, which predicts that when food is limited small males will spend less time feeding and more time mating than will large males. 相似文献
938.
Tokishi Hayashi Hironori Tsuchiya Hiroshi Naruse 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1983,273(2):245-252
This paper describes a sensitive high performance liquid chromatographic method for the quantitative determination of α-keto acids in plasma using a fluorescence detector. This method is about ten times more sensitive than that reported in a previous paper. Only 50 μl of plasma are needed for the determination of α-keto acids. However, p-hydroxyphenylpyruvic acid could not be analysed because the quinoxalinol derived from it does not exhibit fluorescence. 相似文献
939.
Satoru SATO Hironori YASUDA Edward W. EVANS Anthony F. G. DIXON 《Entomological Science》2009,12(2):111-115
Vulnerability of larvae of two species of aphidophagous ladybirds, Adalia bipunctata Linnaeus and Harmonia axyridis Pallas, to cannibalism and intraguild predation was assessed in the laboratory. In the first experiment, a first instar of one of the two above species was kept with a fourth instar of the other species in a Petri dish. The number of times each first instar larva was encountered by the fourth instar larva and the fate of the first instar was determined over a period of 10 min. The fourth instar larvae captured and killed all the first instar larvae of their own species at the first encounter. However, when presented with fourth instar larvae of the other species the first instar larvae of A. bipunctata and H. axyridis were encountered 6.4 ± 1.3 ( n = 10) and 19.4 ± 2.1 ( n = 10), respectively. In this experiment no first instar larvae of H. axyridis , whereas all those of A. bipunctata , were killed. 相似文献
940.
Sho Okamoto Kanji Furuya Shingo Nozaki Keita Aoki Hironori Niki 《Eukaryotic cell》2013,12(9):1235-1243
Many fungi respond to light and regulate fungal development and behavior. A blue light-activated complex has been identified in Neurospora crassa as the product of the wc-1 and wc-2 genes. Orthologs of WC-1 and WC-2 have hitherto been found only in filamentous fungi and not in yeast, with the exception of the basidiomycete pathogenic yeast Cryptococcus. Here, we report that the fission yeast Schizosaccharomyces japonicus responds to blue light depending on Wcs1 and Wcs2, orthologs of components of the WC complex. Surprisingly, those of ascomycete S. japonicus are more closely related to those of the basidiomycete. S. japonicus reversibly changes from yeast to hyphae in response to environmental stresses. After incubation at 30°C, a colony of yeast was formed, and then hyphal cells extended from the periphery of the colony. When light cycles were applied, distinct dark- and bright-colored hyphal cell stripes were formed because the growing hyphal cells had synchronously activated cytokinesis. In addition, temperature cycles of 30°C for 12 h and 35°C for 12 h or of 25°C for 12 h and 30°C for 12 h during incubation in the dark induced a response in the hyphal cells similar to that of light. The stripe formation of the temperature cycles was independent of the wcs genes. Both light and temperature, which are daily external cues, have the same effect on growing hyphal cells. A dual sensing mechanism of external cues allows organisms to adapt to daily changes of environmental alteration. 相似文献