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The CD31 antigen, a member of the immunoglobulin superfamily with a possible cell adhesion function, is expressed on approximately 50% of peripheral blood lymphoid cells at relatively low intensity (10-20% of the level on monocytes). In the accompanying paper we showed that a mAb, 5A2.G5, which identifies a glycosylation-dependent epitope of the CD31 antigen, bound to fewer lymphocytes than two other CD31 mAb, B2B1 and 2BD4, although the 3 antibodies bound equally well to monocytes. We have now analyzed the pattern of expression of epitopes of the CD31 antigen on lymphoid cell subpopulations using two-color immunofluorescence and flow cytometry. Large granular lymphocytes (CD16+), CD8-positive T cells and B cells (SMIg+) were mostly CD31-positive as indicated by the binding of mAb B2B1 and 2BD4. Single populations displaying some overlap with the negative control were obtained in each case. In contrast, CD4-positive T cells fell into two discrete populations with respect to CD31 antigen expression. mAb 5A2.G5 displayed weaker binding to all lymphoid cell types, indicating that the pattern of glycosylation of the CD31 antigen differs between lymphocytes (of all types) and cells of the myeloid lineages. The heterogeneity of CD31 antigen expression by CD4-positive cells was further examined by dual-labelling of purified CD4 cells with mAb B2B1 and CD45RA or CD29 mAb which identify naive and memory T cells respectively. The CD31 antigen was found to be preferentially expressed by the CD45RA-positive, naive cell population. 相似文献
13.
John Gordon Graeme Guy Leonie Walker Paul Nathan Ruth Exley Mike Clemens 《Medical oncology (Northwood, London, England)》1986,3(3-4):269-273
The autocrine growth profile of human B lymphocytes transformed with Epstein-Barr virus (EBV) was found to comprise three distinct components: a B-cell growth factor (BCGF); an interleukin-1 (IL-1)-like activity; an activity requiring cell-to-cell contact for its action. Observations on the inhibition of the EBV-carrying Daudi lymphoma line by α-interferon indicated that loss of response to these autostimulatory factors was underlying growth cessation. Furthermore, a putative for BCGF was found to be down-regulated on B cells stimulated with non-transforming mitogens but constitutively expressed following EBV-transformation. Taken together with recent evidence that normal B cells produce autostimulatory factors, these findings suggest that the special feature of autocrine growth by EBV-immortalized cells is a maintenance of what should normally be a transient phenotype, possibly through deregulation of receptor expression. This hypothesis is discussed. 相似文献
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Lisa S. Barsties Leonie A. Daalderop Jacqueline Lagendijk Frank van Steenbergen Jasper V. Been Loes C.M. Bertens Adja J.M. Waelput Hanneke van Zoest Derk Loorbach Eric A.P. Steegers 《Health policy (Amsterdam, Netherlands)》2021,125(3):385-392
BackgroundHealth inequities are already present at birth and affect individuals’ health and socioeconomic outcomes across the life course. Addressing these inequities requires a cross-sectoral approach, covering the first 1,000 days of life. We believe that - in the Dutch context - municipal governments can be the main responsible actor to drive such an approach, since they are primarily responsible for organising adequate public health. Therefore, we aim to identify and develop transformative change towards the implementation of perinatal health into municipal approaches and policies concerning health inequities.MethodsA transition analysis will be combined with action research in six Dutch municipalities. Interviews and interactive group sessions with professionals and organisations that are relevant for the institutional embedding of perinatal health into approaches and policies regarding health inequities, will be organised in each municipality. As a follow-up, a questionnaire will be administered among all participants one year after completion of the group sessions.DiscussionWe expect to gain insights into the role of municipalities in addressing perinatal health inequities, learn more about the interaction between different key stakeholders, and identify barriers and facilitators for a cross-sectoral approach to perinatal health. This knowledge will serve to inform the development of approaches to perinatal health inequities in areas with relatively poor perinatal health outcomes, both in the Netherlands and abroad. 相似文献
16.
Journal of Public Health - Media reporting can influence the perception and development of attitudes through the frequency and the way certain topics are presented. The German Medical Journal... 相似文献
17.
Lisanne E. de Koning Jessica Warnink-Kavelaars Marion A. van Rossum Diederik Bosman Leonie A. Menke Fransiska Malfait Rosa de Boer Jaap Oosterlaan Raoul H. H. Engelbert Lies Rombaut And the Pediatric Heritable Connective Tissue Disorders Study Group 《American journal of medical genetics. Part A》2023,191(7):1792-1803
The aim of the present study was to investigate the nature and prevalence of nonspecific somatic symptoms, pain and catastrophizing in children with Heritable Connective Tissue Disorders (HCTD), and to determine their association with disability. This observational, multicenter study included 127 children, aged 4–18 years, with Marfan syndrome (MFS) (59%), Loeys-Dietz syndrome (LDS) (8%), Ehlers-Danlos syndromes (EDS) (12%) and hypermobile Ehlers-Danlos syndrome (hEDS) (23%). The assessments included the Children's Somatization Inventory or parent proxy (CSI, PCSI), pain visual-analogue scale (VAS), SUPERKIDZ body diagram, Pain Catastrophizing Scale Child or parent proxy (PCS-C, PCS-P) and Childhood Health Assessment Questionnaire (CHAQ-30). Data from children aged ≥8 years were compared to normative data. In children ≥ 8 years (n = 90), pain was present in 59%, with a median of 4 (IQR = 3–9) pain areas. Compared to normative data, the HCTD group reported significantly higher on the CSI (p ≤ 0.001, d = 0.85), VAS pain intensity (p ≤ 0.001, d = 1.22) and CHAQ-30 (p ≤ 0.001, d = 1.16) and lower on the PCS-C (p = 0.017, d = −0.82) and PCS-P (p ≤ 0.001, d = −0.49). The intensity of nonspecific somatic symptoms and pain explained 45% of the variance in disability (r2 = 0.45 F(2,48) = 19.70, p ≤ 0.001). In children ≤ 7 years (n = 37), pain was present in 35% with a median of 5(IQR = 1–13) pain areas. The mean(SD) VAS scores for pain intensity was 1.5(2.9). Functional disability was moderately correlated to the number of pain areas (r = 0.56, p ≤ 0.001), intensity of nonspecific somatic symptoms (r = 0.63, p ≤ 0.001) and pain (r = 0.83, p ≤ 0.001). In conclusion, this study supports the need for comprehensive assessment of nonspecific somatic symptoms, pain, and disability in children with HCTD to allow tailored treatment. 相似文献
18.
Leonie J. M. Rijks Gerard J. Boer Erik Endert Kora de Bruin Jan C. van den Bos Peter A. P. M. van Doremalen Willem G. E. J. Schoonen Anton G. M. Janssen Eric A. van Royen 《European journal of nuclear medicine and molecular imaging》1996,23(3):295-307
We studied the potential of both stereoisomers of 17-[123I]iodovinyloestradiol (E- andZ-[123I]IVE) and of 11-methoxy-17-[123I]iodovinyloestradiol (E-andZ-[123I]MIVE) as suitable radioligands for the imaging of oestrogen receptor(ER)-positive human breast tumours. The 17-[123I]iodovinyloestradiols were prepared stereospecifically by oxidative radio-iododestannylation of the corresponding 17-tri-n-butylstannylvi-nyloestradiol precursors. Competitive binding studies were performed in order to determine the relative binding affinity (RBA) of the unlabelled 17-iodovinyloes-tradiols for the ER in both human MCF-7 breast tumour cells and rat uterine tissue, compared with that of diethylstilboestrol (DES). Target tissue uptake, retention and uptake selectivity of their123I-labelled analogues were studied in immature female rats. All four 17-iodovi-nyloestradiols showed high affinity for the ER in human MCF-7 cells, as well as rat uterus. Their RBA for the ER showed the following order of decreasing potency: RBA of DES >Z-IVE >Z-MIVE >E-MIVE E-IVE. Neither of these 17-iodovinyloestradiols showed any significant binding to the sex hormone binding globulin in human plasma. The biodistribution studies showed ER-mediated uptake in the uterus, ovaries and pituitary, that ofE- andZ-[123I]MIVE being higher than that ofE- andZ-[123I]IVE. High target-to-non-target tissue uptake ratios, especially at longer periods after injection (up to 24 h), were exhibited by both isomers of [123I]MIVE. The uterus-to-blood uptake ratio was higher forE-[123I]MIVE. However, the uterus-to-fat uptake ratio appeared to be higher for theZ-isomer of [123I]MIVE, especially at 24 h after injection. Metabolic properties and temperature effects, which play a more important role in vivo, probably cause the discrepancies seen between in vitro and in vivo binding results. On the basis of their in vitro binding properties and in vivo distribution characteristics we conclude thatE- andZ-[123I]MIVE could be suitable radioligands for the diagnostic imaging of ER in human breast cancer. Therefore, further studies with these radioligands in mature normal and tumour-bearing rats are warranted. 相似文献
19.
Leonie N. Robin Dr. Michael Kalloniatis 《Documenta ophthalmologica. Advances in ophthalmology》1992,80(4):273-300
Conditions causing a reduction of oxygen availability (anoxia), such as stroke or diabetes, result in drastic changes in ion movements, levels of neurotransmitters and metabolites and subsequent neural death. Currently, there is no clinically available treatment for anoxia induced neural cell death resulting in drastic and permanent central nervous system dysfunction. However, there have been some exciting developments in experimentally induced anoxic conditions where several classes of drugs appear to significantly reduce neural cell death. This report aims to provide the foundations for understanding both the basic mechanisms involved in retinal ischaemic damage and experimental treatments used to prevent such damage. We discuss the normal release, actions and uptake of the fast retinal neurotransmitters, glutamate and GABA, in the vertebrate retina. Immunocytochemistry is used to demonstrate that both glutamate and GABA are found in the macaque retina. Following this is a discussion on how ischaemia may enhance neurotransmitter release or disrupt its uptake, thus causing an increase in extracellular concentration of these neurotransmitters and subsequent neuronal damage. The mechanisms involved in glutamate neurotoxicity are reviewed, because excess glutamate is the likely cause of retinal ischaemic damage. Finally, the mechanisms behind four possible modes of treatment of neurotransmitter toxicity and their advantages and disadvantages are discussed. Hopefully, further research in this area will lead to the development of a rational therapy for retinal, as well as cerebral ischaemia.Abbreviations -KG
-ketoglutarate
- AAT
aspartate amino transferase
- AC
amacrine cell
- ACL
amacrine cell layer
- BC
bipolar cell
- CNS
central nervous system
- EAA
excitatory amino acids
- G'ase
glutaminase
- GABA
-amino butyric acid
- GABA-T
GABA transaminase
- GAD
glumatic acid decarboxylase
- GC
ganglion cell
- GCL
ganglion cell layer
- GDH
glutamate dehydrogenase
- gj
gap junction
- GS
glutamine synthetase
- HC
horizontal cell
- ILM
inner limiting membrane
- INL
inner nuclear layer
- IPC
inter-plexiform cell
- IPL
inner plexiform layer
- IS
inner segment of photoreceptor
- NFL
nerve fibre layer
- NMDA
N-methyl-D-aspartate
- OLM
outer limiting membrane
- ONL
outer nuclear layer
- OPL
outer plexiform layer
- OS
outer segment of photoreceptor
- Ox
acetateoxaloacetate
- RL
receptor layer
- SSAD
succinate semi-aldehyde decarboxylase
- Succinate SA
succinate semi aldehyde
- TCA cycle
tricarboxylic acid cycle 相似文献
20.
Rosie Ashbolt Jenny Barralet Robert Bell Dennis Bittisnich Andrew Black Barry Combs Christine Carson Scott Crerar Craig Dalton Joy Gregory Michelle Harlock Gillian Hall Geoff Hogg Martyn Kirk Karin Lalor Tony Merritt Sally Munnoch Jennie Musto Lillian Mwanri Leonie Neville Chris Oxenford Rhonda Owen Jane Raupach Cameron Sault Russell Stafford Barbara Telfer Hassan Vally Kefle Yohannes 《Communicable diseases intelligence》2005,29(1):85-88