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991.
Flávia Aparecida de Oliveira Eliza Carla Barroso Duarte Cláudia Teixeira Taveira Aline Abreu Máximo Érica Carvalho de Aquino Rita de Cássia Alencar Eneida Franco Vencio 《Head and neck pathology》2009,3(4):271-275
Salivary gland tumors consist of a group of heterogeneous lesions with complex clinicopathological characteristics and distinct
biological behaviors. Worldwide series show a contrast in the relative incidence of salivary gland tumors, with some discrepancies
in clinicopathological data. The main aim of this study was to describe demographic characteristics of 599 cases in a population
from Central Brazil over a 10-year period and compare these with other epidemiological studies. Benign tumors represented
78.3% of the cases. Women were the most affected (61%) and the male:female ratio was 1:1.6. Parotid gland tumors were the
most frequent (68.5% of cases) and patient age ranged from 1 to 88 years-old (median of 45 years old). The most frequent tumors
were pleomorphic adenomas (68.4%) and benign tumors were significantly more frequent in the parotid (75.9%), while malignant
tumors were more frequent in the minor salivary glands (40%) (P < 0.05). In conclusion, women and the parotid gland were the most affected and pleomorphic adenoma was the most frequent
lesion, followed by adenoid cystic carcinoma and Warthin’s tumor. 相似文献
992.
WANG Lei GUO Ji-feng ME Li-luo ZHANG Hai-nan SHEN Lu JIANG Hong PAN Qian XIA Kun TANG Bei-sha YAN Xin-xiang 《中华医学杂志(英文版)》2009,122(24):3082-3085
Parkinson's disease (PD) is the second most common neurodegenerative disorder characterized by a selective loss of nigrostriatal dopaminergic neurons. Clinical manifestations of this complex disease include resting tremor, bradykinesia, postural instability, gait difficulty and rigidity. Approximately 5%-10% of patients have genetic factors, yet etiology of PD remains unclear. Genetic deficits, environmental exposure, oxidative stress, mitochondrial dysfunction, 相似文献
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994.
Prediger RD Franco JL Pandolfo P Medeiros R Duarte FS Di Giunta G Figueiredo CP Farina M Calixto JB Takahashi RN Dafre AL 《Behavioural brain research》2007,177(2):205-213
Considerable evidence supports the role of oxidative stress in the pathogenesis of Alzheimer's disease (AD). Previous studies suggest that the central nervous system (CNS) administration of beta-amyloid peptide, the major constituent of senile plaque in AD, induces oxidative stress in rodents which may contribute to the learning and memory deficits verified in the beta-amyloid model of AD. In the present study, we compared the effects of a single intracerebroventricular (i.c.v.) injection of aggregated beta-amyloid peptide-(1-40) (Abeta(1-40)) (400pmol/mouse) on spatial learning and memory performance, synaptic density and the glutathione (GSH)-dependent antioxidant status in adult male C57BL/6 and Swiss albino mice. Seven days after Abeta(1-40) administration, C57BL/6 and Swiss mice presented similar spatial learning and memory impairments, as evaluated in the water maze task, although these impairments were not found in Abeta(40-1)-treated mice. Moreover, a similar decline of synaptophysin levels was observed in the hippocampus (HC) and prefrontal cortex (PFC) of both Swiss and C57BL/6 mice treated with Abeta(1-40), which suggests synaptic loss. C57BL/6 mice presented lower levels of glutathione-related antioxidant defences (total glutathione (GSH-t) levels, glutathione peroxidase (GPx) and glutathione reductase (GR) activity) in the HC and PFC in comparison to Swiss mice. Despite the reduced basal GSH-dependent antioxidant defences observed in C57BL/6 mice, Abeta(1-40) administration induced significant alterations in the brain antioxidant parameters only in Swiss mice, decreasing GSH-t levels and increasing GPx and GR activity in the HC and PFC 24h after treatment. These results indicate strain differences in the susceptibility to Abeta(1-40)-induced changes in the GSH-dependent antioxidant defences in mice, which should be taken into account in further studies using the Abeta model of AD in mice. In addition, the present findings suggest that the spatial learning and memory deficits induced by beta-amyloid peptides in rodents may not be entirely related to glutathione-dependent antioxidant response. 相似文献
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998.
“Nutcracker esophagus” (NE) is a primary esophageal motor disorder, first described in patients with noncardiac chest pain.
In recent years NE has been associated with gastroesophageal reflux disease (GERD). In this study we compare patients with
NE with and without GERD, as defined by pHmetry or endoscopy, with respect to clinical, endoscopic, radiologic, and manometric
findings. Fifty-two patients with NE were studied. They were divided in two groups: GERD (17–32.6%) and non-GERD (35–67.4%)
patients. Females predominated in both groups, with no significant difference in age (p > 0.05). Chest pain was the chief complaint in both groups (p > 0.05). Clinical findings in patients with and without reflux included chest pain (52.9% and 51.4%), dysphagia (58.8% and
42.8%), and heartburn (64.7% and 42.8%), followed by regurgitation, dyspepsia, ear, nose, and throat (ENT) complaints, respiratory
symptoms, and odynophagia (p > 0.05). Erosive esophagitis was found in three patients (5.7%). There were no differences between groups in the findings
of barium swallow studies and all manometric findings were similar for both groups (p > 0.05). We conclude that there were no differences in patients with NE with or without associated reflux disease. It is
important to diagnose reflux properly so patients can be treated adequately. 相似文献
999.
Molecular screening of Plasmodium sp. asymptomatic carriers among transfusion centers from Brazilian Amazon region 总被引:1,自引:0,他引:1
Fugikaha E Fornazari PA Penhalbel Rde S Lorenzetti A Maroso RD Amoras JT Saraiva AS Silva RU Bonini-Domingos CR Mattos LC Rossit AR Cavasini CE Machado RL 《Revista do Instituto de Medicina Tropical de S?o Paulo》2007,49(1):1-4
The transmission of malaria in Brazil is heterogeneous throughout endemic areas and the presence of asymptomatic Plasmodium sp. carriers (APCs) in the Brazilian Amazon has already been demonstrated. Malaria screening in blood banks is based on the selection of donors in respect to possible risks associated with travel or residence, clinical evidence and/or inaccurate diagnostic methods thereby increasing the probability of transfusion-transmitted infection. We evaluated the frequency of APCs in four blood services in distinct areas of the Brazilian Amazon region. DNA was obtained from 400 human blood samples for testing using the phenol-chloroform method followed by a nested-PCR protocol with species-specific primers. The positivity rate varied from 1 to 3% of blood donors from the four areas with an average of 2.3%. All positive individuals had mixed infections for Plasmodium vivax and Plasmodium falciparum. No significant differences in the results were detected among these areas; the majority of cases originated from the transfusion centres of Porto Velho, Rond?nia State and Macapá, Amapá State. Although it is still unclear whether APC individuals may act as reservoirs of the parasite, efficient screening of APCs and malaria patients in Brazilian blood services from endemic areas needs to be improved. 相似文献
1000.
de Oliveira DC Malta MM Pinheiro JA Piegas LS 《Arquivos brasileiros de cardiologia》2007,88(2):e36-e39
Noncompaction of the myocardium (NCM) is a rare congenital heart defect. It was first described 15 years ago, and few cases are published. The purpose of this study is to describe a NCM case. Clinical findings and imaging test results of a 37-year-old female patient with isolated NCM are presented. The patient complained of palpitations; her physical examination revealed extrasystoles, and her 12-lead electrocardiogram showed ventricular bigeminy. Three-dimensional Doppler echocardiography revealed numerous prominent trabeculations with deep intertrabecular recesses with blood flow which communicated with the ventricular cavity, which were more intense in the septal apical region. Cardiac magnetic resonance imaging corroborated the echocardiographic findings. The clinical presentation and the patients laboratory test results confirmed the diagnosis of isolated NCM. The knowledge of the echocardiographic findings of this disease enables an early diagnosis and a more adequate treatment. 相似文献