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81.
Summary For the initiation of an arousal reaction, the stimulation of the reticular activating system by square waves of frequencies varying from 50 to 400 c/s was studied. To evaluate the stimulation efficiency, the initial frequency of the rhinencephalic arousal reaction was used. The optimal stimulus frequency depends on the duration of the pulses. The optimal frequency was found to be 200 c/s at a pulse duration of 0.5 ms and 100 c/s at a pulse duration of 1.5 ms. 相似文献
82.
83.
G Mayer 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(11):879-882
Daily administration of synthetic ACTH (betaI-23 corticotrophine) from day 15 of pregnancy induces delay or inhibition of parturition in normal or ovariectomized Rats injected or not with estradiol. Parturition takes place at approximatively normal time, when ACTH is stopped and estradiol continued. Radio-immunological assays show an increase of blood progesterone level after ACTH administration in castrated, but not in castrated and adrenalectomized Rats. Mechanisms of ACTH action are discussed. 相似文献
84.
Zusammenfassung Es wird die Wirkung einer Behandlung mit verschiedenen Hormonen und Kostformen auf den Azetateinbau in Fettsäuren bei erblich fettsüchtigen Mäusen und ihren normalen Geschwistern aus dem gleichen Wurf untersucht. Insulin, mit und ohne Glukose verabreicht, steigert die Lipogenese bei beiden Mäusetypen. Wachstumshormon und Glukagon vermindern den Azetateinbau bei den fettsüchtigen, vermehren ihn aber bei nichtfetten Tieren. Glukagon bewirkt bei normalen Tieren eine Steigerung der Einbaurate, die der bei unbehandelten fettsüchtigen gleichkommt. Fütterung einer fettreichen Kost senkt die Lipogenese bei fettsüchtigen Mäusen in stärkerem Ausmass als bei nichtfettsüchtigen.
Supported in part by Grant No. A-49, National Institutes of Arthritis and Metabolism, National Institutes of Health, Bethesda, Maryland; Sugar Research Foundation, New York; Kellog Company, Battle Creek, Michigan; and The Nutrition Foundation, Inc., New York. 相似文献
Supported in part by Grant No. A-49, National Institutes of Arthritis and Metabolism, National Institutes of Health, Bethesda, Maryland; Sugar Research Foundation, New York; Kellog Company, Battle Creek, Michigan; and The Nutrition Foundation, Inc., New York. 相似文献
85.
Zusammenfassung Bei Mäusen und Ratten mit hypothalamischer Fettsucht beobachtet man bei Fütterungad libitum vermehrte Fettbildung, die zurückgeht, wenn man die Tiere hungern lässt. Diese Befunde lassen auf einen «regulatorischen» und nicht «metabolischen» Charakter dieser Fettsucht schliessen.
Supported in part by grants-in-aid from the National Institute of Arthritis and Metabolism (Grant No. A49C2R), National Institutes of Health, Public Health Service, U.S. Department of Health, Education, and Welfare; Sugar Research Foundation, New York City; Kellogg Co., Battle Creek, Michigan; and the J. M. Kaplan Fund, Inc., New York. 相似文献
Supported in part by grants-in-aid from the National Institute of Arthritis and Metabolism (Grant No. A49C2R), National Institutes of Health, Public Health Service, U.S. Department of Health, Education, and Welfare; Sugar Research Foundation, New York City; Kellogg Co., Battle Creek, Michigan; and the J. M. Kaplan Fund, Inc., New York. 相似文献
86.
87.
A. M. Mayer 《Cellular and molecular life sciences : CMLS》1959,15(4):158-158
Zusammenfassung Die fluorometrische Bestimmung von Nukleotiden in Pflanzenextrakten wird durch phenolische Stoffe gestört. Nukleotide können mit dieser Methode nicht routinemässig bestimmt werden. 相似文献
88.
Ruprecht K Mayer J Sauter M Roemer K Mueller-Lantzsch N 《Cellular and molecular life sciences : CMLS》2008,65(21):3366-3382
The genomes of vertebrates contain sequences that are similar to present-day exogenous retroviruses. Such sequences, called
endogenous retroviruses (ERVs), have resulted from ancestral germ line infections by exogenous retroviruses which have thereafter
been transmitted in a Mendelian fashion. By analogy to exogenous tumorigenic retroviruses, ERVs have been implicated in the
pathogenesis of cancer. Cumulative evidence from animal models indicates that ERVs may participate in the process of malignant
transformation or promote tumor growth, e.g. through insertional mutagenesis or via counteracting tumor immunosurveillance.
Here, we review the role of ERVs in tumorigenesis with focus on human ERVs (HERVs) in human cancer. Although available data
suggest a potential role of HERVs in human cancers, in particular germ cell tumors, the contributions of HERVs to human tumorigenesis
warrant further elucidation. (Part of a Multi-author Review) 相似文献
89.
孤岛油田馆(1 2)砂层组属于河流相沉积,其纵向、横向相变迅速,砂体难以大面积追踪,本利用河流结构单元分析法、标准层与辅助标志层控制下的“旋回-厚度”对比法,很好地解决了馆(1 2)地层的划分对比问题,其中馆(1 2)砂层组内辅助标志层的发现为地层的划分对比提供了重要的保证.根据结构单元分析、砂体的岩性特征、粒度特征、河流砂体的空间展布形态以及河流曲率的计算,对馆(1 2)河流沉积的垂向旋回性及沉积模式进行了研究。对比Miall的16种河流分类方案,孤岛油田馆(1 2)砂层组属于细粒曲流河沉积. 相似文献
90.
Safavi-Naeini AH Mayer Alegre TP Chan J Eichenfield M Winger M Lin Q Hill JT Chang DE Painter O 《Nature》2011,472(7341):69-73
Controlling the interaction between localized optical and mechanical excitations has recently become possible following advances in micro- and nanofabrication techniques. So far, most experimental studies of optomechanics have focused on measurement and control of the mechanical subsystem through its interaction with optics, and have led to the experimental demonstration of dynamical back-action cooling and optical rigidity of the mechanical system. Conversely, the optical response of these systems is also modified in the presence of mechanical interactions, leading to effects such as electromagnetically induced transparency (EIT) and parametric normal-mode splitting. In atomic systems, studies of slow and stopped light (applicable to modern optical networks and future quantum networks) have thrust EIT to the forefront of experimental study during the past two decades. Here we demonstrate EIT and tunable optical delays in a nanoscale optomechanical crystal, using the optomechanical nonlinearity to control the velocity of light by way of engineered photon-phonon interactions. Our device is fabricated by simply etching holes into a thin film of silicon. At low temperature (8.7 kelvin), we report an optically tunable delay of 50 nanoseconds with near-unity optical transparency, and superluminal light with a 1.4 microsecond signal advance. These results, while indicating significant progress towards an integrated quantum optomechanical memory, are also relevant to classical signal processing applications. Measurements at room temperature in the analogous regime of electromagnetically induced absorption show the utility of these chip-scale optomechanical systems for optical buffering, amplification, and filtering of microwave-over-optical signals. 相似文献