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961.
From axon–glial signalling to myelination: the integrating role of oligodendroglial Fyn kinase 总被引:1,自引:1,他引:0
Central nervous system myelination requires recognition and signalling processes between neuronal axons and oligodendrocytes.
Complex cellular rearrangements occur in myelination-competent oligodendrocytes requiring spatio-temporal control mechanisms.
Although the molecular repertoire is becoming increasingly transparent, the signalling mechanisms governing myelination initiation
are only poorly understood. The non-receptor tyrosine kinase Fyn has been implicated in axon–glial signal transduction and
in several cellular processes required for oligodendrocyte maturation and myelination. Here, we review oligodendroglial Fyn
signalling and discuss the role of Fyn in axon–glia interaction mediating myelination. 相似文献
962.
Johansson ME Ambort D Pelaseyed T Schütte A Gustafsson JK Ermund A Subramani DB Holmén-Larsson JM Thomsson KA Bergström JH van der Post S Rodriguez-Piñeiro AM Sjövall H Bäckström M Hansson GC 《Cellular and molecular life sciences : CMLS》2011,68(22):3635-3641
In discussions on intestinal protection, the protective capacity of mucus has not been very much considered. The progress in the last years in understanding the molecular nature of mucins, the main building blocks of mucus, has, however, changed this. The intestinal enterocytes have their apical surfaces covered by transmembrane mucins and the whole intestinal surface is further covered by mucus, built around the gel-forming mucin MUC2. The mucus of the small intestine has only one layer, whereas the large intestine has a two-layered mucus where the inner, attached layer has a protective function for the intestine, as it is impermeable to the luminal bacteria. 相似文献
963.
964.
Lin JS Anaclet C Sergeeva OA Haas HL 《Cellular and molecular life sciences : CMLS》2011,68(15):2499-2512
Wakefulness and consciousness depend on perturbation of the cortical soliloquy. Ascending activation of the cerebral cortex
is characteristic for both waking and paradoxical (REM) sleep. These evolutionary conserved activating systems build a network
in the brainstem, midbrain, and diencephalon that contains the neurotransmitters and neuromodulators glutamate, histamine,
acetylcholine, the catecholamines, serotonin, and some neuropeptides orchestrating the different behavioral states. Inhibition
of these waking systems by GABAergic neurons allows sleep. Over the past decades, a prominent role became evident for the
histaminergic and the orexinergic neurons as a hypothalamic waking center. 相似文献
965.
Truman JP Al Gadban MM Smith KJ Hammad SM 《Cellular and molecular life sciences : CMLS》2011,68(20):3293-3305
Macrophages play a central role in innate immune responses, in disposal of cholesterol, and in tissue homeostasis and remodeling.
To perform these vital functions macrophages display high endosomal/lysosomal activities. Recent studies have highlighted
that acid sphingomyelinase (ASMase), which generates ceramide from sphingomyelin, is involved in modulation of membrane structures
and signal transduction in addition to its metabolic role in the lysosome. In this review, we bring together studies on ASMase,
its different forms and locations that are necessary for the macrophage to accomplish its diverse functions. We also address
the importance of ASMase to several disease processes that are mediated by activated macrophages. 相似文献
966.
The history of the Parallelogram Rule for composing physical quantities, such as motions and forces, is marked by conceptual difficulties leading to false starts and halting progress. In particular, authors resisted the required assumption that the magnitude and the direction of a quantity can interact and are jointly necessary to represent the quantity. Consequently, the origins of the Rule cannot be traced to Pseudo-Aristotle or Stevin, as commonly held, but to Fermat, Hobbes, and subsequent developments in the latter part of the seventeenth century. 相似文献
967.
The chaperone protein PapD mediates assembly of pili in Escherichia coli. Its polypeptide chain folds into two immunoglobulin-type domains that are homologous in sequence to the human lymphocyte differentiation antigen Leu-1/CD5. 相似文献
968.
We have investigated the reactivity of different human, rat and cat muscles to a monoclonal antibody directed against human alpha-cardiac myosin heavy chain. We have found that special fiber subpopulations of human masseter and extraocular muscles, as well as the bag fibers of human, rat and cat muscle spindles, were reactive to this antibody, indicating that these fibers expressed alpha-cardiac myosin heavy chain or a closely related isoform. This isomyosin was present in the spindle bag fibers at early fetal stages, whereas its expression in masseter and extraocular muscle fibers was not detected during the first 22 weeks of gestation. Our results add to the list of muscle proteins which are expressed in locations or at developmental stages other than those initially described, suggesting that a revision of the present nomenclature of the subgroups of myosin heavy chains might be considered in the future. 相似文献
969.
The mouse insulin-like growth factor type-2 receptor is imprinted and closely linked to the Tme locus. 总被引:49,自引:0,他引:49
T-associated maternal effect (Tme) is the only known maternal-effect mutation in the mouse. The defect is nuclear-encoded and embryos that inherit a deletion of the Tme locus from their mother die at day 15 of gestation. There are many genomically imprinted regions known in the mouse genome but so far no imprinted genes have been cloned. The Tme locus is absent in two chromosome-17 deletion mutants, Thp and the tLub2, and its position has been localized using these deletions to a 1-cM region. We report here that the genes for insulin-like growth factor type-2 receptor (Igf2r) and mitochondrial superoxide dismutase-2 (Sod-2) are absent from both deletions. Probes for these genes and for plasminogen (Plg) and T-complex peptide 1 (Tcp-1) were used in pulsed-field gel mapping to show that Tme must lie within a region of 800-1,100 kb. We also demonstrate that embryos express Igf2r only from the maternal chromosome, and that Tcp-1, Plg and Sod-2 are expressed from both chromosomes. Therefore Igf2r is imprinted and closely linked or identical to Tme. 相似文献
970.
Blastocyst implantation depends on maternal expression of leukaemia inhibitory factor. 总被引:87,自引:0,他引:87
C L Stewart P Kaspar L J Brunet H Bhatt I Gadi F K?ntgen S J Abbondanzo 《Nature》1992,359(6390):76-79
A critical point during mammalian pregnancy is the implantation of the blastocyst when the embryo attaches to the wall of the uterus. The autonomously developing preimplantation embryo then becomes dependent on the maternal environment for its continued development. Little is known about the regulation of implantation, except that a complex interaction between peptide and steroid hormones synchronizes the preparation of the uterus for implantation with the development of the embryo. Whether the implantation event is under maternal or embryonic control is also unclear (reviewed in refs 1, 2). We have previously shown that a cytokine, leukaemia inhibitory factor (LIF), is expressed in the uterine endometrial glands specifically on the fourth day of pregnancy. This burst of expression is under maternal control and always precedes implantation of the blastocyst. Here we report that transient expression of LIF in mice is essential for implantation. Females lacking a functional LIF gene are fertile, but their blastocysts fail to implant and do not develop. The blastocysts, however, are viable and, when transferred to wild-type pseudopregnant recipients, they can implant and develop to term. 相似文献