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81.
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Wayne E. Jones Jr. Jasper Chiguma Edwin Johnson Ashok Pachamuthu Daryl Santos 《Materials》2010,3(2):1478-1496
Nanocomposites made up of polymer matrices and carbon nanotubes are a class of advanced materials with great application potential in electronics packaging. Nanocomposites with carbon nanotubes as fillers have been designed with the aim of exploiting the high thermal, electrical and mechanical properties characteristic of carbon nanotubes. Heat dissipation in electronic devices requires interface materials with high thermal conductivity. Here, current developments and challenges in the application of nanotubes as fillers in polymer matrices are explored. The blending together of nanotubes and polymers result in what are known as nanocomposites. Among the most pressing current issues related to nanocomposite fabrication are (i) dispersion of carbon nanotubes in the polymer host, (ii) carbon nanotube-polymer interaction and the nature of the interface, and (iii) alignment of carbon nanotubes in a polymer matrix. These issues are believed to be directly related to the electrical and thermal performance of nanocomposites. The recent progress in the fabrication of nanocomposites with carbon nanotubes as fillers and their potential application in electronics packaging as thermal interface materials is also reported. 相似文献
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Jasper E. Visser MD PhD David J. Schretlen PhD Bastiaan R. Bloem MD PhD Hyder A. Jinnah MD PhD 《Movement disorders》2011,26(4):746-749
Lesch‐Nyhan disease (LND) is characterized by dystonia, cognitive abnormalities, and self‐injurious behavior. No effective therapies are available. LND is associated with a presynaptic dopaminergic deficit, but the reported effects of dopamine replacement therapy are conflicting. The current prospective open‐label study assesses the effects of levodopa on both neurological and behavioral features of LND. All 6 study participants discontinued levodopa early, due to lack of effect and sometimes worsening of motor function. The results provide important clues for pathophysiological mechanisms and suggestions for future treatment options. © 2011 Movement Disorder Society 相似文献
85.
Endocrine regulation of the balance between skeletal muscle anabolism and catabolism has been investigated extensively. Factors determining whether hormones exert anabolic or catabolic influences are multifaceted and often unclear. Testosterone, growth hormone, insulin and insulin-like growth factor-I have complex anabolic effects, some of which have only recently been elucidated, and are important regulators of muscle remodeling, whereas glucocorticoids have direct catabolic effects and induce muscle protein loss. The effects of estrogen are poorly understood and warrant further study. We review recent literature and evaluate the hormones driving skeletal muscle anabolism and catabolism, which ultimately dictate the endocrinology and metabolism of skeletal muscle in humans. Understanding hormonal regulation of skeletal muscle remodeling might facilitate development of improved hormone-mediated therapies for muscle wasting conditions. 相似文献
86.
Trevelyan J Brull DJ Needham EW Montgomery HE Morris A Mattu RK 《The American journal of cardiology》2004,94(5):564-569
Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers may have anti-inflammatory actions, an effect that could explain some of their beneficial effects on cardiovascular events in clinical trials. Coronary artery bypass grafting (CABG) is associated with a systemic inflammatory response and provides a convenient model to examine the effects of such agents. Genetic polymorphisms may be important in influencing the expression of cytokines, such as interleukin-6 (IL-6). We randomized men awaiting CABG to treatment with enalapril, losartan, or control for 2 months before surgery. Systemic IL-6, IL-8, IL-10, and IL-1 receptor agonists were measured before and after surgery, and genotypes for the -174 G/C and -572 G/C IL-6 gene polymorphisms were determined. Total release of the IL-1 receptor agonist was decreased 29% by enalapril and 31% by losartan (adjusted p = 0.041). IL-6 was decreased 17% by enalapril and 20% by losartan. Subjects possessing the -174 GG genotype produced 20% more IL-6 (adjusted p = 0.029). In these high producers of IL-6, release of IL-6 was decreased 51% by enalapril (adjusted p = 0.001) and 32% by losartan (adjusted p = 0.068). Release of IL-10 was nonsignificantly decreased 26% by enalapril and 21% by losartan, whereas IL-8 was not detected. In conclusion, enalapril and losartan significantly decreased release of the IL-1 receptor agonist after CABG. Enalapril produced a highly significant decrease of 51% in the release of IL-6 in patients identified as high producers of IL-6 by the -174 G/C polymorphism, whereas losartan has a similar but less marked effect. The production of IL-6 in this setting is influenced by the -174 G/C polymorphism. 相似文献
87.
We prospectively and blindly assessed the diagnostic and prognostic impact of implementation of the European Society of Cardiology/American College of Cardiology recommendations for redefinition of myocardial infarction (MI) in an unselected cohort of patients with suspected cardiac chest pain, with particular attention to prespecified clinical groups. All patients admitted to our institute with suspected cardiac chest pain were enrolled. Physicians provided usual care using serial electrocardiograms/creatine kinase (CK)/aspartate transaminase according to World Health Organization (WHO) criteria for MI, while blinded to additional measurements of cardiac troponin T (cTnT) and CK-MB mass. After discharge, diagnoses based on WHO and new criteria were compared, and major adverse cardiac events monitored for 6 months. Implementation of the new recommendations classified an additional 26.1% of patients as having MI compared with WHO criteria, and produced an overall diagnostic alteration in 11.5%. Two thirds of the additional patients with MI were previously diagnosed with unstable angina, whereas one third had "other cardiac" or "noncardiac" diagnoses. A similar MI cohort to the cTnT diagnosis was identified using a CK-MB mass discriminator value of 5 microg/L, but not 10 microg/L. The 6-month prognosis was similar in patients diagnosed with MI by new (cTnT) and WHO criteria, with the new criteria thus identifying a further high-risk cohort in the WHO negative group. In our cohort, the new Joint European Society of Cardiology/American College of Cardiology recommendations identify one fourth more patients as having MI. The 6-month prognosis of those patients reclassified as having MI was similar to those diagnosed with MI by both criteria. 相似文献
88.
Green JB Fricke B Chetty MC von Düring M Preston GF Stewart GW 《Blood cells, molecules & diseases》2004,32(3):411-422
The 32kD membrane protein stomatin was first studied because it is deficient from the red cell membrane in two forms of the class of haemolytic anaemias known as "hereditary stomatocytosis." The hallmark of these conditions is a plasma membrane leak to the monovalent cations Na+ and K+: the protein is missing only in the most severely leaky of these conditions. No mutation has ever been found in the stomatin gene in these conditions. Stomatin-like proteins have been identified in all three domains of biology, yet their function remains enigmatic. Although the murine knock-out is without phenotype, we have identified a family showing a splicing defect in the stomatin mRNA, in which affected children showed a catastrophic multisystem disease not inconsistent with the now-known wide tissue distribution of stomatin. We report here a study of strongly homologous stomatin-like genes in prokaryotes, which reveals a close connection with a never-studied gene erroneously known as "nfed." This gene codes for a hydrophobic protein with a probable serine protease motif. It is possible that these stomatin-like genes and those which are known as"nfed" form an operon, suggesting that the two protein products are aimed at a common function. The corollary is that stomatin could be a partner protein for a membrane-bound proteolytic process, in both prokaryotes and in eukaryotes generally: this idea is consistent with experimental evidence. 相似文献
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90.
Pierre-Eric Juif Matthias Hoch Daniele D’Ambrosio Jasper Dingemanse 《Drugs in R&D》2015,15(2):203-210