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991.
Although individual cases have been reported in the literature, serious infections of the central nervous system (CNS) such as arachnoiditis, meningitis, and abscess following spinal or epidural anesthesia are rare. However, recent epidemiologic series from Europe suggest that the frequency of infectious complications associated with neuraxial techniques may be increasing. Importantly, while meningitis and epidural abscess are both complications of neuraxial block, the risk factors and causative organisms are disparate. For example, staphylococcus is the organism most commonly associated epidural abscess; often these infections occurred in patients with impaired immunity. Conversely, meningitis follows dural puncture, and is typically caused by alpha-hemolytic streptococci, with the source of the organism the nasopharynx of the proceduralist. In order to reduce the risk of serious infection following neuraxial blockade, the clinician must be knowledgeable in the pathogenesis of CNS infections, patient selection, and use of meticulous aseptic technique. Finally, since delay in the diagnosis may result in morbidity and even death, it is crucial to be aware of the presenting signs and symptoms of meningitis and epidural abscess. 相似文献
992.
A novel spatial environment consists of several different types of information that may be encoded by cellular information storage mechanisms such as long-term potentiation (LTP) and long-term depression (LTD). Arousal, mediated, for example, by activation of the noradrenergic system, is a critical factor in information acquisition and may enhance the encoding of novel spatial information. Using electrophysiological recordings of hippocampal responses in freely moving rats during spatial learning, we investigated the role of the beta-adrenoreceptor in Schaeffer collateral-CA1 synaptic plasticity. We found that novel exploration of spatial context facilitates induction of LTD that is inhibited by intracerebroventricular application of the beta-adrenoreceptor antagonist, propranolol. Long-lasting homosynaptic LTD, that was electrically induced by low-frequency stimulation, was unaffected by the antagonist. Although application of a beta-adrenoreceptor agonist (isoproterenol) did not affect electrically induced LTD, agonist application facilitated short-term depression (STD) into LTD and mimicked the augmentation, through spatial exploration, of STD into LTD. Exploration of a novel empty environment facilitated LTP that was prevented by application of propranolol. These results suggest that beta-adrenoreceptors may facilitate encoding of spatial information through synaptic plasticity in the hippocampus and that noradrenaline is a key factor in effective information acquisition. 相似文献
993.
Gildengers AG Butters MA Chisholm D Reynolds CF Mulsant BH 《International journal of geriatric psychiatry》2008,23(7):693-698
OBJECTIVE: To determine whether donepezil is effective in enhancing cognitive functioning and instrumental activities of daily living (IADLs) in older adults with bipolar disorder. METHODS: Twelve elderly patients with bipolar I or II disorder, with evidence of mild cognitive decrements, were administered donepezil 5-10 mg daily for 3 months. Participants had cognitive and functional evaluation pre-, on-, and 3-months post donepezil administration. RESULTS: Three subjects dropped out of the study. In the remaining nine subjects, no significant effects were observed in cognitive and functional measures. Seven of the nine participants asked to resume the medication after completion of the study because of the perceived beneficial effects. CONCLUSIONS: In this small pilot study of older adults with bipolar disorder, acute treatment with donepezil was not associated with improvements in cognitive and IADL functioning. Given limitations of the study design, placebo effects could not be ruled out in the subjects who asked to resume donepezil. 相似文献
994.
995.
Schachter HM Girardi A Ly M Lacroix D Lumb AB van Berkom J Gill R 《Child and adolescent psychiatry and mental health》2008,2(1):18
Stigmatizing, or discriminatory, perspectives and behaviour, which target individuals on the basis of their mental health,
are observed in even the youngest school children. We conducted a systematic review of the published and unpublished, scientific
literature concerning the benefits and harms of school-based interventions, which were directed at students 18 years of age
or younger to prevent or eliminate such stigmatization. Forty relevant studies were identified, yet only a qualitative synthesis
was deemed appropriate. Five limitations within the evidence base constituted barriers to drawing conclusive inferences about
the effectiveness and harms of school-based interventions: poor reporting quality, a dearth of randomized controlled trial
evidence, poor methods quality for all research designs, considerable clinical heterogeneity, and inconsistent or null results.
Nevertheless, certain suggestive evidence derived both from within and beyond our evidence base has allowed us to recommend
the development, implementation and evaluation of a curriculum, which fosters the development of empathy and, in turn, an
orientation toward social inclusion and inclusiveness. These effects may be achieved largely by bringing especially but not
exclusively the youngest children into direct, structured contact with an infant, and likely only the oldest children and
youth into direct contact with individuals experiencing mental health difficulties. The possible value of using educational
activities, materials and contents to enhance hypothesized benefits accruing to direct contact also requires investigation.
Overall, the curriculum might serve as primary prevention for some students and as secondary prevention for others. 相似文献
996.
Almeida-Gomes M Vrcibradic D Siqueira CC Kiefer MC Klaion T Almeida-Santos P Nascimento D Ariani CV Borges-Junior VN Freitas-Filho RF van Sluys M Rocha CF 《Anais da Academia Brasileira de Ciências》2008,80(2):291-300
We studied the herpetofaunal community from the Atlantic forest of Morro S?o Jo?o, in Rio de Janeiro State, Brazil, and present data on species composition, richness, relative abundance and densities. We combined three sampling methods: plot sampling, visual encounter surveys and pit-fall traps. We recorded sixteen species of amphibians and nine of reptiles. The estimated densities (based on results of plot sampling) were 4.5 ind/100 m2 for amphibians and 0.8 ind/100 m2 for lizards, and the overall density (amphibians and lizards) was 5.3 ind/100 m2. For amphibians, Eleutherodactylus and Scinax were the most speciose genera with three species each, and Eleutherodactylus binotatus was the most abundant species (mean density of 3.0 frogs/100 m2). The reptile community of Morro S?o Jo?o was dominated by species of the families Gekkonidae and Gymnophtalmidae (Lacertilia) and Colubridae (Serpentes). The gymnophtalmid lizard Leposoma scincoides was the most abundant reptile species (mean density of 0.3 ind/100 m2). We compare densities obtained in our study data with those of other studied rainforest sites in various tropical regions of the world. 相似文献
997.
Viana ML Pontes RM Garcia WE Fávero ME Prete DC Matsuo T 《Arquivos de gastroenterologia》2007,44(3):210-214
BACKGROUND: Crohn's disease is an inflammatory bowel disease associated with a wide variety of complications and manifestations secondary to the effects of underlie inflammatory process. In about 30% of the patients with Crohn's disease can be found extra-intestinals symptoms. Nephrolithiasis is one of them and the appearance of kidney stones, mainly of oxalate of calcium, is more common in these patients than in general population. AIM: To evaluate urinary metabolic factors potentially involved in renal stones formation on patients with Crohn's disease. METHODS: We evaluated 29 patients with Crohn's disease followed in the Outpatient Bowel Inflammatory Disease Clinics of State University Hospital, Londrina, PR, Brazil, from January to December of 2004. The metabolic evaluation included measured of blood and urine substances related to renal stones formation, kidneys, ureters and bladder ultrasonography and calculation of urinary supersaturation for calcium oxalate, uric acid and calcium phosphate. RESULTS: Twenty-nine of the evaluated patients were female or 65.5% and 34.5% were males. Among the metabolic urinary studied, we identified the following potential disturbances associated with nephrolithiasis: hypocitraturia in 21 patients (72.4%), hypomagnesuria in 12 (41.4%), hyperoxaluria in 4 (13.6%) and urinary volume low in 5 (17.2%). Renal stones were identified in 13 patients (44.8%). Oxalate urinary excretion was higher in patients submitted to bowel surgery and also in patients with ileum resection. The urinary supersaturation of calcium oxalate and brushita in patients with bowels surgery was higher than the other patients not submitted to any surgery. Data to compare patients who underwent to surgery or not were analyzed by Mann-Whitney test (U test), and Qui-square test or the accurate test of Fisher have been used to determine variables association. For all tests 5% of significance level was considered. CONCLUSION: This study shows that the frequency of renal stones in patients suffering from Crohns disease is higher than in general population and, also, higher than that described elsewhere for this disease. We identified hypocitraturia and hypomagnesiuria as the main factors which could explain our data. The impact of these metabolic disturbances can be also evaluated by means of the high supersaturation obtained for calcium oxalate and calcium phosphate which suggests the way those factors could be influencing crystal nucleation and, consequently, lead to renal stones formation in this group of patients. 相似文献
998.
999.
1000.
Gu TL Mercher T Tyner JW Goss VL Walters DK Cornejo MG Reeves C Popova L Lee K Heinrich MC Rush J Daibata M Miyoshi I Gilliland DG Druker BJ Polakiewicz RD 《Blood》2007,110(1):323-333
Activated tyrosine kinases have been frequently implicated in the pathogenesis of cancer, including acute myeloid leukemia (AML), and are validated targets for therapeutic intervention with small-molecule kinase inhibitors. To identify novel activated tyrosine kinases in AML, we used a discovery platform consisting of immunoaffinity profiling coupled to mass spectrometry that identifies large numbers of tyrosine-phosphorylated proteins, including active kinases. This method revealed the presence of an activated colony-stimulating factor 1 receptor (CSF1R) kinase in the acute megakaryoblastic leukemia (AMKL) cell line MKPL-1. Further studies using siRNA and a small-molecule inhibitor showed that CSF1R is essential for the growth and survival of MKPL-1 cells. DNA sequence analysis of cDNA generated by 5'RACE from CSF1R coding sequences identified a novel fusion of the RNA binding motif 6 (RBM6) gene to CSF1R gene generated presumably by a t(3;5)(p21;q33) translocation. Expression of the RBM6-CSF1R fusion protein conferred interleukin-3 (IL-3)-independent growth in BaF3 cells, and induces a myeloid proliferative disease (MPD) with features of megakaryoblastic leukemia in a murine transplant model. These findings identify a novel potential therapeutic target in leukemogenesis, and demonstrate the utility of phosphoproteomic strategies for discovery of tyrosine kinase alleles. 相似文献