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31.
Summary Bayesian analysis is given of a random effects binary probit model that allows for heteroscedasticity. Real and simulated examples illustrate the approach and show that ignoring heteroscedasticity when it exists may lead to biased estimates and poor prediction. The computation is carried out by an efficient Markov chain Monte Carlo sampling scheme that generates the parameters in blocks. We use the Bayes factor, cross‐validation of the predictive density, the deviance information criterion and Receiver Operating Characteristic (ROC) curves for model comparison. 相似文献
32.
Reframing climate change as a public health issue: an exploratory study of public reactions 总被引:1,自引:0,他引:1
Edward W Maibach Matthew Nisbet Paula Baldwin Karen Akerlof Guoqing Diao 《BMC public health》2010,10(1):299
Background
Climate change is taking a toll on human health, and some leaders in the public health community have urged their colleagues to give voice to its health implications. Previous research has shown that Americans are only dimly aware of the health implications of climate change, yet the literature on issue framing suggests that providing a novel frame - such as human health - may be potentially useful in enhancing public engagement. We conducted an exploratory study in the United States of people's reactions to a public health-framed short essay on climate change. 相似文献33.
34.
Edward H Livingston 《Surgery for obesity and related diseases》2007,3(1):14-20; discussion 20
BACKGROUND: Administrative databases have increasingly been used to assess bariatric surgery outcomes, resulting in policy recommendations about bariatric practice. However, surgical outcomes must be risk adjusted to compare patients of varying potential risk fairly with those to whom the policies will apply. To date, the risk adjustment tools used for database analysis of bariatric surgical outcomes have been those designed for other purposes, and their sensitivity for bariatric outcomes has not been established. METHODS: Bariatric surgical procedures contained in the National Hospital Discharge Summary for 1993-2003 were assembled into a database. The standard set of Elixhauser co-morbidity variables used by the Agency for Healthcare Research and Quality were entered into the database. Those variables that were significantly associated with adverse outcomes were entered into a stepwise-elimination logistic regression equation, yielding a set of variables related to adverse outcomes from bariatric surgery. These were then prospectively applied to another database (the National Inpatient Survey) to determine their sensitivity for predicting outcomes and were compared with the commonly used Charlson score. RESULTS: The variables significantly correlating with bariatric adverse events included chronic pulmonary disease, hypertension, diabetes with chronic complications, fluid and electrolyte disorders, deficiency anemias, and depression. Age and male gender were also signficantly related to adverse events. The c-index (a correlative index, with .5 showing no, and 1, a perfect, relationship) for bariatric surgery mortality with the Charlson index is .52. For the Elixhauser-based system we developed, it is .72. CONCLUSIONS: We have developed a new risk-adjustment tool for bariatric surgery outcomes studies that use administrative databases. Its performance was clearly better than that of the commonly used Charlson co-morbidity score. Bariatric studies that have used the Charlson index should not be considered adequately risk adjusted. 相似文献
35.
Genetic variation in serotonin transporter alters resting brain function in healthy individuals. 总被引:1,自引:0,他引:1
Hengyi Rao Seth J Gillihan Jiongjiong Wang Marc Korczykowski Geena Mary V Sankoorikal Kristin A Kaercher Edward S Brodkin John A Detre Martha J Farah 《Neuropsychopharmacology》2007,62(6):600-606
BACKGROUND: Perfusion functional magnetic resonance imaging (fMRI) was used to investigate the effect of genetic variation of the human serotonin transporter (5-HTT) gene (5-HTTLPR, SLC6A4) on resting brain function of healthy individuals. METHODS: Twenty-six healthy subjects, half homozygous for the 5-HTTLPR short allele (s/s group) and half homozygous for the long allele (l/l group), underwent perfusion functional and structural magnetic resonance imaging during a resting state. The two genotype groups had no psychiatric illness and were similar in age, gender, and personality scores. RESULTS: Compared with the l/l group, the s/s group showed significantly increased resting cerebral blood flow (CBF) in the amygdala and decreased CBF in the ventromedial prefrontal cortex. The effect of functional modulation in these regions by 5-HTTLPR genotype cannot be accounted for by variations in brain anatomy, personality, or self-reported mood. CONCLUSIONS: The 5-HTTLPR genotype alters resting brain function in emotion-related regions in healthy individuals, including the amygdala and ventromedial prefrontal cortex. Such alterations suggest a broad role of the 5-HTT gene in brain function that may be associated with the genetic susceptibility for mood disorders such as depression. 相似文献
36.
Satellite cells express distinct patterns of myogenic proteins in immature skeletal muscle. 总被引:1,自引:0,他引:1
Edward Schultz Connie Chamberlain Kathleen M McCormick Paul E Mozdziak 《Developmental dynamics》2006,235(12):3230-3239
Satellite cells are the myogenic cells lying between the myofiber sarcolemma and basal lamina. The objective of this study was to determine the expression patterns of MyoD, myogenin, and Pax7 within the satellite cell population in the growing rat soleus and extensor digitorum longus (EDL) muscles. Secondly, the expression of the myogenic markers was also studied within the interstitial cell compartment and myonuclei. It was discovered that the soleus contained a higher number of Pax7, MyoD, or myogenin-positive nuclei compared with the EDL. Similarly, myogenin was expressed at a lower level in the myonuclei of the soleus compared with the EDL, and myogenin was expressed at a higher level in the interstitial compartment of the soleus compared with the EDL. When interstitial nuclei, myonuclei, and double-labeled nuclei were used in the estimate of the satellite cell population, it was discovered that approximately of 13% of the myofibers in a transverse section of the soleus muscle and 4.1% of EDL myofibers exhibit a labeled satellite cell nucleus. Overall, results from this study suggest that expression patterns of these markers vary predictably among muscles with different growth dynamics and phenotypic characteristics. 相似文献
37.
Beyond C4d: Other Complement-Related Diagnostic Approaches to Antibody-Mediated Rejection 总被引:3,自引:0,他引:3
William M. Baldwin III Edward K. Kasper rea A. Zachary Barbara A. Wasowska E. Rene Rodriguez 《American journal of transplantation》2004,4(3):311-318
Complement is a multifunctional system of receptors and regulators as well as effector molecules. Both the pathogenic and diagnostic power of complement is based on the capacity of the complement system to amplify innate and adaptive immunity. This amplification is accomplished through two strategies: (1) enzymatic reactions in the complement cascade, and (2) stimulation of leukocytes, platelets and parenchymal cells through specific receptors or receptor-independent pore formation. The mechanisms by which complement mediates and modifies nonspecific inflammation, antibody-mediated injury and T-cell responses are of particular significance to the pathogenesis of transplant rejection. Understanding the mechanisms by which complement integrates the interactions of leukocytes, platelets and parenchymal cells offers opportunities to further refine the diagnosis of rejection. 相似文献
38.
Ian F. Dunn Pankaj K. Agarwalla Alexander M. Papanastassiou William E. Butler Edward R. Smith 《Child's nervous system》2007,23(10):1191-1194
Objective Approximately 10% of patients with neurofibromatosis I (NFI) patients will have central nervous system (CNS) tumors. The most
common of these are hypothalamic–optic gliomas, followed by brainstem and cerebellar pilocytic astrocytomas. While isolated
pilocytic astrocytomas in NFI are well described, the appearance of multiple pilocytic astrocytomas in an individual patient
is less common. The most frequent combination in NFI patients with more than one pilocytic astrocytoma is optic tract/hypothalamic
and brainstem. Other combinations are exceedingly rare; multiple pilocytic astrocytomas have only been reported once in the
cerebral hemispheres in a patient with NFI. This report presents the first documented case, to our knowledge, of multiple
pilocytic astrocytomas in the cerebellum of a patient with NF1.
Methods Case report.
Conclusion The finding of multiple cerebellar pilocytic astrocytomas in a patient with NF1 is important because it expands the spectrum
of presentations for patients with NF1 and also highlights specific diagnostic and therapeutic challenges faced by the treating
physicians. The genetic and molecular basis of NF1 is reviewed. Strategies of diagnosis and treatment outlined here are relevant
to both patients with NF1 and all patients with multiple posterior fossa tumors. 相似文献
39.