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101.
Medical sciences are rapidly emerging as a data rich discipline where the amount of databases and their dimensionality increases
exponentially with time. Data integration algorithms often rely upon discovering embedded, useful, and novel relationships
between feature attributes that describe the data. Such algorithms require data integration prior to knowledge discovery,
which can lack the timeliness, scalability, robustness, and reliability of discovered knowledge. Knowledge integration algorithms
offer pattern discovery on segmented and distributed databases but require sophisticated methods for pattern merging and evaluating
integration quality. We propose a unique computational framework for discovering and integrating frequent sets of features
from distributed databases and then exploiting them for unsupervised learning from the integrated space. Assorted indices
of cluster quality are used to assess the accuracy of knowledge merging. The approach preserves significant cluster quality
under various cluster distributions and noise conditions. Exhaustive experimentation is performed to further evaluate the
scalability and robustness of the proposed methodology. 相似文献
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103.
Micro-RNA (miRNA) mediated regulation of messenger RNA (mRNA) complexity in the central nervous system (CNS) is emerging as a critical factor in the control of CNS-specific gene expression during development, plasticity, aging and disease. In these studies, miRNA array and Northern blot based tracking of specific miRNA abundances and decay kinetics in human neural (HN) cells in primary culture and in short post-mortem interval (PMI, ∼1 h) human brain tissues showed a limited stability and relatively short half-life (∼1–3.5 h) for specific brain-enriched miRNAs. In short PMI Alzheimer's disease (AD)-affected temporal lobe neocortex, miRNA-9, miRNA-125b and miRNA-146a were found to be significantly up-regulated, an effect that was not seen in several related neurological disorders. The results suggest (a) that unless specifically stabilized, certain brain-enriched miRNAs represent a rapidly executed signaling system employing highly transient effectors of CNS gene expression, and (b) that in AD temporal lobe neocortex specific brain miRNAs are significantly up-regulated in abundance and strongly correlate with the presence of AD-type neuropatholgical change. 相似文献
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105.
Dahai Gao Shishir P. S. Chundawat Anurag Sethi Venkatesh Balan S. Gnanakaran Bruce E. Dale 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(27):10922-10927
Substrate binding is typically one of the rate-limiting steps preceding enzyme catalytic action during homogeneous reactions. However, interfacial-based enzyme catalysis on insoluble crystalline substrates, like cellulose, has additional bottlenecks of individual biopolymer chain decrystallization from the substrate interface followed by its processive depolymerization to soluble sugars. This additional decrystallization step has ramifications on the role of enzyme–substrate binding and its relationship to overall catalytic efficiency. We found that altering the crystalline structure of cellulose from its native allomorph Iβ to IIII results in 40–50% lower binding partition coefficient for fungal cellulases, but surprisingly, it enhanced hydrolytic activity on the latter allomorph. We developed a comprehensive kinetic model for processive cellulases acting on insoluble substrates to explain this anomalous finding. Our model predicts that a reduction in the effective binding affinity to the substrate coupled with an increase in the decrystallization procession rate of individual cellulose chains from the substrate surface into the enzyme active site can reproduce our anomalous experimental findings. 相似文献
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Patients at times present with neurological symptoms and signs for which at times extensive investigation fails to identify any structural or organic pathology within the nervous system. These pseudo neurological syndromes can mimic almost any organic disease of the central and peripheral nervous system. Some such as pseudo seizures also referred to as psychogenic non-epileptic seizures (PNES) are more commonly encountered than others. Pseudo neurological syndromes presenting as mononeuropathies have been documented in the neurological literature. We document here a patient presenting with wrist drop suggestive of radial nerve palsy and illustrate a simple clinical test which can help differentiate between true and false (pseudo) radial nerve palsy. 相似文献
109.
A total of 20 previously untreated children with growth hormone deficiency (GHD) were treated for one year with biosynthetic human growth hormone (hGH). The mean chronologic age was 9.43±3.52 years with a height age of 5.02 years, and bone age 9.43±3.52 (TW2-RUS) 6.42 years. The mean pretreatment growth velocity was 2.43±0.90 cm/year. Of these 14 children had complete GHD (peak GH levels less than 5 ng/ml) and 6 had partial GHD. They were treated with recombinant GH in a dose of 0.5 IU/kg/week divided into 6–7 injections per week subcutaneously at night. The mean growth velocity increased to 8.88±2.10 cm/yr at the end of 6 months and 8.00±2.21 cm/yr at 12 months. The actual gain ranged from 6–11 cm in a year. There were no local adverse reactions. One child developed vitiligo of the face and another transient hyperglycemia. 相似文献
110.
The burden of disease due to injuries has elicited virtually no public health response in the countries of central and eastern Europe, even though injuries have long been a much greater problem in the east of Europe than in the west, with children especially affected. This paper seeks to identify factors that have inhibited policy development on this topic and to draw lessons for health policy development in this region more generally. Several factors emerge. Deaths from injuries have had low visibility. Data have not been assembled in a way that would facilitate identification of the burden of disease that they constitute. Those organizations responsible for public health, whether within government or at local level, were typically very weak with little capacity either to identify the nature and scale of threats to the health of their populations or to develop strategies to address them. There was uncertainty about ownership, with fragmentation of responsibility but no tradition of intersectoral working. Non-governmental organizations, which have placed injuries on the health policy agenda in the west, are weak or non-existent. International donors, who could have had a role, have focused on issues such as health care reform. This analysis provides a potential framework for examining policy responses, or lack thereof, to other health challenges in this region. It highlights the need for a better understanding of the potential for using available data, which, in turn, requires a major strengthening of capacity. However, in many countries, there is a need for new ways of working, involving a broadening of the sense of ownership, with clearly designated responsibilities but designed in ways that encourage rather than inhibit intersectoral action. There is also a need to develop non-governmental organizations that have sufficient capacity to undertake their own analyses and to place issues on the agenda. 相似文献