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241.
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Erik N. T. P. Bakker Brian J. Bacskai Michal Arbel-Ornath Roxana Aldea Beatrice Bedussi Alan W. J. Morris Roy O. Weller Roxana O. Carare 《Cellular and molecular neurobiology》2016,36(2):181-194
The lymphatic clearance pathways of the brain are different compared to the other organs of the body and have been the subject of heated debates. Drainage of brain extracellular fluids, particularly interstitial fluid (ISF) and cerebrospinal fluid (CSF), is not only important for volume regulation, but also for removal of waste products such as amyloid beta (Aβ). CSF plays a special role in clinical medicine, as it is available for analysis of biomarkers for Alzheimer’s disease. Despite the lack of a complete anatomical and physiological picture of the communications between the subarachnoid space (SAS) and the brain parenchyma, it is often assumed that Aβ is cleared from the cerebral ISF into the CSF. Recent work suggests that clearance of the brain mainly occurs during sleep, with a specific role for peri- and para-vascular spaces as drainage pathways from the brain parenchyma. However, the direction of flow, the anatomical structures involved and the driving forces remain elusive, with partially conflicting data in literature. The presence of Aβ in the glia limitans in Alzheimer’s disease suggests a direct communication of ISF with CSF. Nonetheless, there is also the well-described pathology of cerebral amyloid angiopathy associated with the failure of perivascular drainage of Aβ. Herein, we review the role of the vasculature and the impact of vascular pathology on the peri- and para-vascular clearance pathways of the brain. The different views on the possible routes for ISF drainage of the brain are discussed in the context of pathological significance. 相似文献
243.
Markus V. Heppt Thomas K. Eigentler Katharina C. Kähler Rudolf A. Herbst Daniela Göppner Thilo Gambichler Jens Ulrich Edgar Dippel Carmen Loquai Beatrice Schell Bastian Schilling Susanne G. Schäd Erwin S. Schultz Fanny Matheis Julia K. Tietze Carola Berking 《Cancer immunology, immunotherapy : CII》2016,65(8):951-959
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Na,K-ATPase (EC, 3.6.1.37, Na,K-ATPase) is a fundamental vital membrane transport and receptor system which, after biosynthesis,
is exported to the plasma membrane in inside-out vesicles. Na,K-ATPase can be extracted form the natural membrane and inserted
into artificially formed phosphatidylcholine vesicles (liposomes). The ultrastructure of the reconstituted vesicles has been
fully described. In the present work, the Na,K-ATPase-vesicles were labeled with fluorescent tracers either in their water
or membrane phase, incubated with freshly isolated human lymphocytes, and the resulting cellular fluorescence measured with
fluorescence activated cell sorting (FACS), confocal microscopy and spectrofluorometry. The FACS data show that all lymphocytes
take up Na,K-ATPase-vesicles in a dose-and temperature-dependent fashion. Three-dimensional analysis of the fluorescence by
confocal microscopy reveals that the fluorescence is contained within the cells. Quantitative determination by spectrofluorometry
indicates that depending on the vesicle/cell ratio, a single lymphocyte takes up 650 to 36,500 vesicles within 30 min at 37°C
together with up to about 200,000 renal Na,K-ATPase molecules. 相似文献
246.
Suzanne C. Dieudonn Janet M. Kerr Tianshun Xu Beatrice Sommer Anna R. DeRubeis Sergei A. Kuznetsov In‐San Kim Pamela Gehron Robey Marian F. Young 《Journal of cellular biochemistry》2000,76(2):231-243
Human bone marrow stromal cells (hBMSC) are pluripotent cells that have the ability to differentiate into bone, cartilage, hematopoietic‐supportive stroma, and adipocytes in a process modulated by dexamethasone (DEX). To characterize changes in hBMSC in response to DEX, we carried out differential display experiments using hBMSC cultured for 1 week in the presence or absence of 10−8 M DEX. When RNA from these cells was used for differential display, numerous cDNA bands were identified that were up‐regulated and down‐regulated by DEX. The cDNA bands were reamplified by PCR and directly used to screen an hBMSC cDNA library. Seven clones were isolated and characterized by DNA sequencing and found to encode the following genes: transforming growth factor‐β‐induced gene product (βig‐h3), calphobindin II, cytosolic thyroid‐binding protein, 22‐kDA smooth muscle protein (SM22), and the extracellular matrix proteins osteonectin/SPARC, type III collagen, and fibronectin. To confirm that these genes were regulated by DEX, the cells were treated continuously with this hormone for periods ranging from 2 to 30 days, and steady‐state mRNA levels were measured by Northern blot analysis. All genes showed some level of regulation by DEX. The most profound regulation by DEX was observed in the βig‐h3 gene, which showed a relative 10‐fold decrease in mRNA levels after 6 days of treatment. Interestingly, βig‐h3 expression was not altered by DEX in fibroblasts from other human tissues, including thymus stromal fibroblasts, spleen stromal fibroblasts, and foreskin fibroblasts. In summary, differential display of DEX‐treated hBMSC revealed unique patterns of gene expression and has provided new information about phenotypic changes that accompany the differentiation of hBMSC toward osteogenesis. J. Cell. Biochem. 76:231–243, 1999. Published 1999 Wiley‐Liss, Inc. 相似文献
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Salvatore de Maria Vittoria Metafora Salvatore Metafora Gianpietro Ravagnan Maria Cartení Gabriele Pontoni Angelo Facchiano Marilena Lepretti Beatrice Severino Giuseppe Caliendo Vincenzo Santagada Ingrid Langer Patrick Robberecht 《Journal of peptide science》2008,14(1):102-109
Increase of VPAC receptor s binding to the (16)gamma-glutamyl diaminopropane vasoactive intestinal peptide (VIP-DAP) agonist, a vasoactive intestinal polypeptide (VIP) structural analogue containing a positive charge at position 16, has confirmed the importance of a positive charge at this site. By investigating the effect of distance from the peptide backbone Calpha of a positive charge in position 16, data are reported here concerning: (i) a novel chemical method used for the synthesis of a new family of (16)gamma-glutamyl diamine VIP derivatives differing among them for single carbon atoms and including diaminoethane (VIP-DAE2), diaminopropane (VIP-DAP3), diaminobutane (VIP-DAB4), diaminopentane (VIP-DAP5), and diaminohexane (VIP-DAH6); (ii) functional characterization of these compounds on human VPAC1 and VPAC2 receptors. In more detail, the EC50 and IC50 values, when measured as a function of the alkylic chain length, show in more detail, that the use of VIP-DAB4 derivative changes the IC50 but not the EC50, thus indicating on hVPAC2 receptor an unexpected relationship between binding and activity that differs from that obtained on hVPAC1. 相似文献
250.
Elkan AC Sjöberg B Kolsrud B Ringertz B Hafström I Frostegård J 《Arthritis research & therapy》2008,10(2):R34