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51.
52.
Rutger L. van Bezooijen Marco C. DeRuiter Nathalie Vilain Rui M. Monteiro Annemieke Visser Lianne van der Wee‐Pals Conny J. van Munsteren Pancras C.W. Hogendoorn Michel Aguet Christine L. Mummery Socrates E. Papapoulos Peter Ten Dijke Clemens W.G.M. Löwik 《Developmental dynamics》2007,236(2):606-612
Spatial-temporal regulation of bone morphogenetic protein (BMP) and Wnt activity is essential for normal cardiovascular development, and altered activity of these growth factors causes maldevelopment of the cardiac outflow tract and great arteries. In the present study, we show that SOST, a Dan family member reported to antagonize BMP and Wnt activity, is expressed within the medial vessel wall of the great arteries containing smooth muscle cells. The ascending aorta, aortic arch, brachiocephalic artery, common carotids, and pulmonary trunk were all associated with SOST expressing smooth muscle cells, while the heart itself, including the valves, and more distal arteries, that is, pulmonary arteries, subclavian arteries, and descending aorta, were negative. SOST was expressed from embryonic day 15.5 up to the neonatal period. SOST expression, however, did not correspond with inhibition of Smad-dependent BMP activity or beta-catenin-dependent Wnt activity in the great arteries. Activity of both signaling pathways was already down-regulated before induction of SOST expression. 相似文献
53.
Kirsten Mehlig Christopher Holmberg Leonie H. Bogl Eva Erhardt Charalambos Hadjigeorgiou Antje Hebestreit Jaakko Kaprio Fabio Lauria Nathalie Michels Iris Pigeot Lucia A. Reisch Toomas Veidebaum Lauren Lissner 《Obesity facts》2021,14(1):121
BackgroundDuring adolescence, health behaviors and weight status are increasingly influenced by friendship and peer networks. This paper examines resemblances in weight-related characteristics and how they differ by sociodemographic factors.MethodsOver 3,000 friendships were reported by 1,603 adolescents, aged 11–16 years, who participated in the school-based I. Family study in 6 European countries. Each “source child” named 1–10 friends for whom standardized weight-related traits were available in the same survey. The mean value of the friends'' traits weighted by time spent together was calculated, and related to the source child''s trait. Country, age and sex of the source child, parental education, and immigrant background were considered for confounding and moderation.ResultsSource children''s z-scores of body fat percent and BMI were positively associated with their friends'' characteristics, in particular if they had highly educated parents. Positive associations were also found regarding the frequency of fast-food consumption, impulsivity, screen time, preference for sugar-sweetened foods, and hours spent in sports clubs, in increasing order of effect size. Additionally, correlations were observed between friends'' cognitive and school functioning and being bullied. No associations were seen for a preference for high-fat foods, weight concerns, and health-related quality of life. Finally, parental education and immigrant background were associated between friends in all countries except Sweden, where no associations were observed.ConclusionAdolescent friends shared a number of weight-related characteristics. For weight measures per se, positive associations with friends'' characteristics were only observed in adolescents with high parental education. Associations regarding energy-balance behaviors and indicators of school-related well-being did not differ by parental education. Parental education and immigrant background correlated positively in friends in most countries showing that social aggregation is already occurring in adolescence. The wide spectrum of friendship associations in weight-related traits and behaviors suggests that health promotion initiatives in adolescents should be directed towards peer groups in both school-related and leisure-time environments.ISRCTN RegistryPan-European IDEFICS/I. Family children cohort (ID ISRCTN62310987; https://doi.org/10.1186/ISRCTN62310987). 相似文献
54.
Reciprocal translocations in breast tumor cell lines: cloning of a t(3;20) that targets the FHIT gene 总被引:1,自引:0,他引:1
55.
Andrulis IL Anton-Culver H Beck J Bove B Boyd J Buys S Godwin AK Hopper JL Li F Neuhausen SL Ozcelik H Peel D Santella RM Southey MC van Orsouw NJ Venter DJ Vijg J Whittemore AS;Cooperative Family Registry for Breast Cancer studies 《Human mutation》2002,20(1):65-73
A number of methods are used for mutational analysis of BRCA1, a large multi-exon gene. A comparison was made of five methods to detect mutations generating premature stop codons that are predicted to result in synthesis of a truncated protein in BRCA1. These included four DNA-based methods: two-dimensional gene scanning (TDGS), denaturing high performance liquid chromatography (DHPLC), enzymatic mutation detection (EMD), and single strand conformation polymorphism analysis (SSCP) and an RNA/DNA-based protein truncation test (PTT) with and without complementary 5' sequencing. DNA and RNA samples isolated from 21 coded lymphoblastoid cell line samples were tested. These specimens had previously been analyzed by direct automated DNA sequencing, considered to be the optimum method for mutation detection. The set of 21 cell lines included 14 samples with 13 unique frameshift or nonsense mutations, three samples with two unique splice site mutations, and four samples without deleterious mutations. The present study focused on the detection of protein-truncating mutations, those that have been reported most often to be disease-causing alterations that segregate with cancer in families. PTT with complementary 5' sequencing correctly identified all 15 deleterious mutations. Not surprisingly, the DNA-based techniques did not detect a deletion of exon 22. EMD and DHPLC identified all of the mutations with the exception of the exon 22 deletion. Two mutations were initially missed by TDGS, but could be detected after slight changes in the test design, and five truncating mutations were missed by SSCP. It will continue to be important to use complementary methods for mutational analysis. 相似文献
56.
Ferrer I Kapfhammer JP Hindelang C Kemp S Troffer-Charlier N Broccoli V Callyzot N Mooyer P Selhorst J Vreken P Wanders RJ Mandel JL Pujol A 《Human molecular genetics》2005,14(23):3565-3577
ATP-binding cassette (ABC) transporters facilitate unidirectional translocation of chemically diverse substances, ranging from peptides to lipids, across cell or organelle membranes. In peroxisomes, a subfamily of four ABC transporters (ABCD1 to ABCD4) has been related to fatty acid transport, because patients with mutations in ABCD1 (ALD gene) suffer from X-linked adrenoleukodystrophy (X-ALD), a disease characterized by an accumulation of very-long-chain fatty acids (VLCFAs). Inactivation in the mouse of the abcd1 gene leads to a late-onset neurodegenerative condition, comparable to the late-onset form of X-ALD [Pujol, A., Hindelang, C., Callizot, N., Bartsch, U., Schachner, M. and Mandel, J.L. (2002) Late onset neurological phenotype of the X-ALD gene inactivation in mice: a mouse model for adrenomyeloneuropathy. Hum. Mol. Genet., 11, 499-505.]. In the present work, we have generated and characterized a mouse deficient for abcd2, the closest paralog to abcd1. The main pathological feature in abcd2-/- mice is a late-onset cerebellar and sensory ataxia, with loss of cerebellar Purkinje cells and dorsal root ganglia cell degeneration, correlating with accumulation of VLCFAs in the latter cellular population. Axonal degeneration was present in dorsal and ventral columns in spinal cord. We have identified mitochondrial, Golgi and endoplasmic reticulum damage as the underlying pathological mechanism, thus providing evidence of a disturbed organelle cross-talk, which may be at the origin of the pathological cascade. 相似文献
57.
Faucher M Guillot C Marqueste T Kipson N Mayet-Sornay MH Desplanches D Jammes Y Badier M 《Pflügers Archiv : European journal of physiology》2005,450(1):45-52
This study tried to differentiate the consequences of chronic hypoxia on the electrophysiological and physiological properties and the histological characteristics of slow and fast muscles in rats. Animals inhaled a 10% O2 concentration for a 1-month period. Then, slow [soleus (SOL)] and fast [extensor digitorum longus (EDL)] muscles were analyzed in vitro by physiological and electrophysiological measurements and histological analyses. The results were compared to those obtained in corresponding muscles of an age-matched normoxic group. After exposure to hypoxia: (1) in SOL, there was a tendency to elevated Fmax, a significant increase in twitch force and tetanic frequency and a shortening of M-wave duration, and a reduced percentage of type I fibres, whereas the proportion of type IIa fibres doubled; (2) in EDL, Fmax and tetanic frequency were lowered, the muscle became less resistant to fatigue, and the proportion of type IId/x fibres was halved. Then, after 1 month of hypoxia, in the SOL muscle, both the contractile and histological properties resemble those of a fast muscle. By contrast, the EDL became slower, despite its histology was modestly affected. Reduced muscle use in hypoxia could explain the tendency for deteriorating adaptations in EDL, and the faster properties of SOL could result from hypoxia-induced inhibition of the growth-related fast-to-slow shift in muscle fibre types. 相似文献
58.
Origin and filiation of human plasmacytoid dendritic cells 总被引:8,自引:0,他引:8
Brière F Bendriss-Vermare N Delale T Burg S Corbet C Rissoan MC Chaperot L Plumas J Jacob MC Trinchieri G Bates EE 《Human immunology》2002,63(12):1081-1093
Human plasmacytoid dendritic cells represent a rare population of leukocytes which produce high amounts of type I interferon in response to certain viruses. Although those cells were first described in 1958, there are still unsolved issues related to their origin and function. Recently, a leukemic counterpart of plasmacytoid dendritic cells was identified. Molecular approaches using either normal or leukemic plasmacytoid dendritic cells provide some new insights into the controversial lymphoid origin of those cells. The need for specific markers is still a critical aspect for the identification of plasmacytoid dendritic cells, whatever stage of differentiation, in normal as well as in pathological conditions. Hopefully, novel markers will allow delineation of the relationships between dendritic cells at different stages of differentiation/maturation along the myeloid and lymphoid lineages. 相似文献
59.
Margaux Serey‐Gaut Marcello Scala Bruno Reversade Lyse Ruaud Christelle Cabrol Francesco Musacchia Annalaura Torella Andrea Accogli Nathalie Escande‐Beillard Jean Langlais Gianluca Piatelli Alessandro Consales Vincenzo Nigro Valeria Capra Lionel Van Maldergem 《American journal of medical genetics. Part A》2020,182(6):1466-1472
The clinical and radiological spectrum of spondylocostal dysostosis syndromes encompasses distinctive costo‐vertebral anomalies. RIPPLY2 biallelic pathogenic variants were described in two distinct cervical spine malformation syndromes: Klippel–Feil syndrome and posterior cervical spine malformation. RIPPLY2 is involved in the determination of rostro‐caudal polarity and somite patterning during development. To date, only four cases have been reported. The current report aims at further delineating the posterior malformation in three new patients. Three patients from two unrelated families underwent clinical and radiological examination through X‐ray, 3D computed tomography and brain magnetic resonance imaging. After informed consent was obtained, family‐based whole exome sequencing (WES) was performed. Complex vertebral segmentation defects in the cervico‐thoracic spine were observed in all patients. WES led to the identification of the homozygous splicing variant c.240‐4T>G in all subjects. This variant is predicted to result in aberrant splicing of Exon 4. The current report highlights a subtype of cervical spine malformation with major atlo‐axoidal malformation compromising spinal cord integrity. This distinctive mutation‐specific pattern of malformation differs from Klippel–Feil syndrome and broadens the current classification, defining a sub‐type of RIPPLY2‐related skeletal disorder. Of note, the phenotype of one patient overlaps with oculo‐auriculo‐vertebral spectrum disorder. 相似文献
60.
Contreras X Bennasser Y Chazal N Moreau M Leclerc C Tkaczuk J Bahraoui E 《Virology》2005,332(1):316-328
HIV-1 Tat protein, acting at the cell membrane, stimulates the production by human monocytes of TNF-α, a cytokine implicated in both HIV-1 replication and pathogenesis. Here, we analyze, in primary human monocytes, the mechanisms involved in Tat-stimulated calcium mobilization and its relationship with TNF-α production. We show that the Tat protein induces a calcium signal by mobilizing calcium from extracellular stores. This calcium signal is totally blocked when cells are stimulated in the presence of DHP receptor inhibitors such as nimodipine or calcicludine, thus suggesting the implication of this L-type calcium channel. By using RT-PCR amplification, Western blot with antibodies directed against the α1D subunit, binding assays with specific agonists or antagonists, and inhibition with specific antisense oligonucleotides, we show that DHP receptors are expressed and functional in primary human monocytes. Interestingly, we demonstrate that Tat-induced calcium mobilization is tightly linked to TNF-α production, thus indicating that Tat-induced mobilization and TNF-α production are entirely mediated by DHP receptors, as shown by their total inhibition by nimodipine, calcicludine, or anti-α1D antisense oligonucleotides. 相似文献