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781.
Dr. Dharam V. Ablashi Paul H. Levine Caterina De Vinci James E. Whitman Jr. Giancarlo Pizza Dimitri Viza 《Biotherapy》1996,9(1-3):81-86
Specific Human Herpes virus-6 (HHV-6) transfer factor (TF) preparation, administered to two chronic fatigue syndrome patients,
inhibited the HHV-6 infection. Prior to treatment, both patients exhibited an activated HHV-6 infection. TF treatment significantly
improved the clinical manifestations of CFS in one patient who resumed normal duties within weeks, whereas no clinical improvement
was observed in the second patient. It is concluded that HHV-6 specific TF may be of significant value in controlling HHV-6
infection and related illnesses. 相似文献
782.
783.
Kuang Yu Chen Dimitri A. Kyriakidis E.S. Canellakis 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,716(1):72-78
The addition of fresh serum-containing growth medium to L1210 mouse leukemic cells in culture resulted in a 5-fold increase in ornithine decarboxylase (l-ornithine carboxy-lyase, EC 4.1.1.17) activity. The presence of microtubule disrupting agents (colchine, vinblastine) or cations (5–10 mM K+, Na+ or Mg2+) abolishes this increase of ornithine decarboxylase activity (Chen, K.Y., Heller, J.S. and Canellakis, E.S. (1976) Biochem. Biophys. Res. Commun. 70, 212–219). Based on these observations we proposed that fluctuation in cellular cation concentrations may act as a link between the membrane structure and ornithine decarboxylase. To test this proposal, we studied the effects of selective membrane perturbing agents such as ionophores and local anesthetics, on the serum-stimulated increase of ornithine decarboxylase activity in L1210 cells. Among the six inonophores tested, valinomycin was the most potent one, with I50 value (concentration that gives 50% inhibition of orthinine decarbocylase activity) of 6·10?9 M. Dibucaine and tetracaine were also effective inhibitors at 10?4?10?5 M. The I50 values of valinomycin on the protein synthesis and RNA synthesis, however, were greater than 1·10?6 M. These results substantiate the notion that ornithine decarboxylase activity can be regulated at plasma membrane level and such regulation is related to the perturbation of cellular cation pools. 相似文献
784.
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786.
G Paternot M Spiessens D Verstreken J Van Bauwel S Debrock TM D'Hooghe C Spiessens 《Reproductive biology and endocrinology : RB&E》2012,10(1):78
ABSTRACT: BACKGROUND: Cell-cell communication and adhesion are essential for the compaction process of early stage embryos. The aim of this study was to develop a noninvasive objective calculation system of embryo compaction in order to test the hypothesis that embryos with a larger mean contact surface result in a higher live birth rate compared to embryos with a lower mean contact surface. METHODS: Multilevel images of 474 embryos transferred on day 3 were evaluated by the Cellify software. This software calculates the contact surfaces between the blastomeres. The primary outcome of this study was live birth. An ideal range of contact surface was determined and the positive and negative predictive value, the sensitivity, the specificity and the area under the curve for this new characteristic were calculated. RESULTS: In total, 115 (24%) transferred embryos resulted in a live birth. Selection of an embryo for transfer on its mean contact surface could predict live birth with a high sensitivity (80%) and high negative predicting value (83%) but with a low positive predictive value (27%), a low specificity (31%) and low area under the ROC curve (0.56). The mean contact surface of embryos cultured in the single medium was significantly higher compared to the mean contact surface of embryos cultured in the sequential medium (p = 0.0003). CONCLUSIONS: Neither the mean contact surface nor the number of contact surfaces of a day 3 embryo had an additional value in the prediction of live birth. The type of culture medium, however, had an impact on the contact surface of an embryo. Embryos cultured in a single medium had a significant larger contact surface compared to embryos cultured in the sequential medium. 相似文献
787.
Abstract. The syllid polychaete Odontosyllis phosphorea produces brilliant displays of green bioluminescence during mating swarms. We studied freshly collected individuals of O. phosphorea in the laboratory to understand the characteristics of its luminescent system. Light emission appeared as an intense glow after stimulation with potassium chloride, and was associated with secreted mucus. The mucus was viscous, blue in color, and exhibited a long-lasting glow that was greatly intensified by addition of peroxidase or ammonium persulfate. The emission spectrum of mucus-associated bioluminescence was unimodal, with a maximum emission in the green spectrum between 494 and 504 nm. The fluorescence emission spectrum was similar, but the fluorescence intensity was low unless it originated from mucus that had already produced light, suggesting that the oxidized product of the light production is the source of fluorescence. Individuals as small as 0.5–1.0 mm produced bioluminescence that was mainly internal and not secreted as mucus. The early occurrence of bioluminescence in the life cycle of members of O. phosphorea suggests that bioluminescence may be used for purposes other than attracting mates. The luminous system was functional at temperatures as low as −20°C and was degraded above 40°C. Mixing hot and cold extracts of the mucus did not result in reconstituting original levels of light emission. Additionally, mucus samples exposed to oxygen depletion by bubbling with argon or nitrogen were still able to produce intense bioluminescence. These results suggest that bioluminescence from the mucus may involve a photoprotein rather than a luciferin–luciferase reaction. 相似文献
788.
789.
790.
Biotinylation of chemically glycosylated bovine serum albumin, yielding a panel of neoglycoproteins, and of desialylated, naturally occurring glycoproteins allowed to systematically evaluate presence and distribution of various types of endogenous sugar receptors in the sections of human glioblastomas and gangliocytomas by a routine histochemical procedure. Pronounced cytoplasmic staining with markers, carrying constituents of natural glycoconjugates, e.g. for beta-galactoside-specific receptors, contrasted with the different intensities, noticed for alpha- and beta-glucoside-specific receptors. Significant qualitative differences between the two tumor types were detected with N-acetyl-D-galactosamine- and sialic acid-carrying probes. Nuclear staining with only a part of the applied panel underscored the specificity of the protein-carbohydrate interaction. Fine structural features of the synthetic neoglycoproteins, e.g. the mode of coupling of the carbohydrate moiety to the protein, were found to exert a significant influence on their suitability as histochemical markers. On the basis of the histochemical results, exemplary biochemical analysis of certain classes of endogenous sugar receptors by affinity chromatography and subsequent gel electrophoresis, namely of beta-galactoside-, alpha-fucoside-, alpha-mannoside- and alpha-glucoside-specific proteins, revealed presence and characteristics of respective sugar receptors that can contribute to the histochemical staining. Similar extent of histochemical staining with the respective probes notwithstanding, the different tumor types exhibited qualitative differences in the expression of individual endogenous sugar receptors. The combined histochemical and biochemical analysis is supposed to be of conspicuous value for biological and clinical investigations on endogenous sugar receptors. 相似文献