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排序方式: 共有1424条查询结果,搜索用时 15 毫秒
71.
Atrial automaticity and atrioventricular conduction in athletes: contribution of autonomic regulation 总被引:2,自引:0,他引:2
Stein R Moraes RS Cavalcanti AV Ferlin EL Zimerman LI Ribeiro JP 《European journal of applied physiology》2000,82(1-2):155-157
Little is known about the sinoatrial automatism and atrioventricular conduction of trained individuals who present a normal
resting electrocardiogram. We used transesophageal atrial stimulation, a minimally invasive technique, to evaluate aerobically
trained athletes (n=10) and sedentary individuals (n=10) with normal resting electrocardiograms, to test the hypothesis that parasympathetic tone, as detected by heart rate variability,
could be associated with changes in sinoatrial automatism and atrioventricular conduction. Corrected sinus node recovery time
tended to be longer in athletes than in sedentary individuals, but this difference did not reach statistical significance.
The Wenckebach point occurred at a lower rate in athletes than in the controls. Over a 24-h period of measurement, the mean
RR interval was longer in the athletes than in the sedentary individuals. The mean square root of successive differences (rMSSD)
tended to be higher in athletes than in controls, but this difference did not reach statistical significance. There was a
moderate correlation (r=0.48, P < 0.05) between the index of atrioventricular conduction, the rate at the Wenckebach point, and the logarithmically transformed
rMSSD. Thus, as a corollary to its effects on the sinus node, where increased parasympathetic tone, decreased sympathetic
tone, and non-autonomic components may contribute to sinus bradycardia, it is possible that athletic training may also induce
intrinsic adaptations in the conduction system, which could contribute to the higher prevalence of atrioventricular conduction
abnormalities observed in athletes.
Accepted: 2 January 2000 相似文献
72.
Gisah Amaral de Carvalho Gilberto Paz-Filho Teresa C. Cavalcanti Hans Graf 《Endocrine pathology》2009,20(4):204-208
Thyroid nodules can be biopsied by fine needle aspiration (FNA) or fine needle capillary (FNC) biopsies. However, there is
controversy on whether one technique is superior to another. In a randomized cytopathologist-blinded cross-sectional study,
260 patients (238 females, age 43.2 ± 12.6) with nodular (82.7%) and diffuse goiter (17.3%) underwent 520 FNAs and 520 FNCs
(not guided by ultrasound). Smears were scored for sample adequacy, and diagnosed as malignant, benign, suspicious, or nondiagnostic.
Diagnostic accuracy was calculated based on the histological findings of 58 patients submitted to surgery. Intra-technique
diagnostic accuracy and sample adequacy was seen in all samples. FNA and FNC provided similar cytological diagnosis, respectively
(benign: 75.8% vs. 74.2%, p = 0.600; malignant: 3.8% vs. 3.8%, p = 0.871; suspicious: 10.4% vs. 10.8%, p = 0.913; and nondiagnostic: 10.0% vs. 11.2%, p = 0.598). Adequacy scores were similar by FNA (7.94 ± 2.84) and FNC (7.96 ± 2.81, p = 0.909). The same proportion of adequate or superior samples was seen in both techniques (91.6%). Sensitivity was equal
to 85.7% for FNA and 100% for FNC. Similarly, specificity was 100% for both techniques. FNA and FNC provide the similar sample
adequacy and diagnostic accuracy. The choice of technique should be based on the operator’s personal preferences and experience. 相似文献
73.
S Bonvalot M Bonnay L Drouard-Troalen A Cavalcanti C Le Péchoux A Le Cesne J Y Blay F Laborde 《European journal of surgical oncology》2007,33(1):114-118
BACKGROUND: Isolated pelvic perfusion exposes tissue to high drug doses and may benefit patients with advanced malignancy. However, leakage is a limit to this technique. AIMS: The aim of the study is to increase the perfusion ratio between local and systemic compartments on isolated pelvic perfusion. We hypothesised that an inflated pressure-suit placed above the level of aortic and caval stop flow could decrease leakage from the regional to the systemic blood compartment in a bovine model. METHOD: As the size of the pressure-suit was adapted for use in humans, we performed our experimental study on 6 calves which are big enough to fit into the suit. We used an inflated pressure-suit placed at low (40mmHg) and high pressures (125mmHg) above the level of aortic and caval stop-flow. A pharmacokinetic study with cisplatinum was performed in both compartments. RESULTS: After injection of the drug, the mean ratio of drug concentration in the locoregional/systemic compartment was 43.1. After 30min, this mean ratio was 4 and 9.7 for a pressure-suit pressure of 40mmHg and 125mmHg, respectively. At pressure-suit pressures of 40mmHg and 125mmHg, pelvic perfusion achieved pelvic/systemic exposure ratios of 5.9 and 14.9 at 30min, respectively. Leakage at 30min was higher when the pressure-suit was inflated at low pressure (40mmHg, mean 18%). When the pressure-suit was inflated at high pressure, leakage was lower (125mmHg, mean 7%). CONCLUSIONS: The pressure-suit increased the perfusion ratio between pelvic and systemic compartments in a bovine model. 相似文献
74.
P D L Lima D S Leite M C Vasconcellos B C Cavalcanti R A Santos L V Costa-Lotufo C Pessoa M O Moraes R R Burbano 《Food and chemical toxicology》2007,45(7):1154-1159
Aluminum (Al) is the most abundant metal and the third common chemical element on earth. It is known that Al is toxic, especially its trivalent form (Al(3+)), that represents the its most soluble form. Al intoxication is related to some pathogenic disorders, principally neurodegeneratives ones as Parkinson and Alzheimer diseases. The present study aimed to evaluate the mutagenic potential of aluminum chloride (AlCl(3)). Comet assay and chromosome aberrations analysis were applied to evaluate the DNA-damaging and clastogenic effects of AlCl(3), respectively, in different phases of the cell cycle. Cultured human lymphocytes were treated with 5, 10, 15 and 25 microM aluminum chloride during the G1, G1/S, S (pulses of 1 and 6h), and G2 phases of the cell cycle. All tested concentrations were cytotoxic and reduced significantly the mitotic index in all phases of cell cycle. They also induced DNA damage and were clastogenic in all phases of cell cycle, specially in S phase. AlCl(3) also induced endoreduplication and polyploidy in treatments performed during G1 phase. The presence of genotoxicity and polyploidy on interphase and mitosis, respectively, suggests that aluminum chloride is clastogenic and indirectly affects the construction of mitotic fuse in all tested concentrations. 相似文献
75.
OBJECTIVES: A study was conducted to determine the prevalence of HPV infection in cervical lesions of Brazilian women and to search for specific risk factors associated to progression to malignancy. METHODS: Five hundred and fourteen paraffin-embedded biopsies obtained from female cervical lesions were classified according to the Bethesda System in low grade squamous intraepithelial lesion (LSIL), high grade SIL (HSIL) and squamous cell carcinoma (SCC). Specimens were tested for the presence of human papillomavirus (HPV) types 6/11,16/18 and 31/33/35 DNA using non-isotopic in situ hybridization. RESULTS: HPV prevalence ranged from 85.6% in LSIL to 55.2% in SCC. Patients were analysed through an 8 year period: 27. 1% of the lesions spontaneously regressed while 43.6% persisted and 29.3% progressed to carcinoma. High risk types were present in 80.5% (Crude OR 13.8, P=0.0003) of the progressive lesions. Possible co-factors have also been evaluated: history of other sexually transmitted diseases, mainly syphilis, showed to be positively related to progression (Adjusted OR 13.0, P=0.0003) while oral contraceptive use and tobacco smoking were not significantly related to it (P>O.1). Association of two or more co-factors also proved to be related to progression. CONCLUSIONS: Oncogenic HPV types 16 and 18 and history of other concurrent sexually transmitted diseases were found to be significantly associated with progression to cancer. Smoking and the use of oral contraceptives did not show a relation to cancer establishment, but when they were associated a significant co-operative role in progression was demonstrated. Our study indicated that HPV and other risk factors for cancer can act together, corroborating the observation of a poor prognosis for Brazilian women presenting SILs. 相似文献
76.
Erdheim-Chester disease in Brazil 总被引:1,自引:1,他引:0
77.
Goldenhar's syndrome--case report 总被引:1,自引:0,他引:1
Goldenhar's syndrome is a rare condition described initially in the early 1950's. It is characterized by a combination of anomalies: dermal epibulbar cysts, auricular appendices and malformation of the ears. In 1963, Gorlin suggested the name oculo-auriculo-vertebral (OAV) dysplasia for this condition and also included vertebral anomalies as signs of the syndrome. The etiology of this rare disease is not fully understood, as it has shown itself variable genetically and of unclear causes. This work reports a case of Goldenhar's syndrome in an 11-year-old female, who presented all classical signs of this rare condition 相似文献
78.
Mancini MC Teixeira S de Araújo LG Paixão ML Magalhães Lde C Coelho ZA Gontijo AP Furtado SR Sampaio RF da Fonseca ST 《Arquivos de neuro-psiquiatria》2002,60(4):974-980
OBJECTIVE: To compare the development of motor function in children born preterm with those born at term, at 8 and 12 months of age. To investigate the relation of motor function quality at the age of 8 months with motor ability at 12 months. METHOD: Thirty-two children participated in this study: 16 were born preterm (risk group) and 16 were born at term (control group). The spontaneous movements of the children were assessed at 8 months and their mobility skills and independence were assessed at 12 months (corrected ages for the preterm group), using standardized developmental tests (AIMS and PEDI, respectively). Data were analysed using independent t-tests (between-group comparison) and Pearson correlation coefficients (within-group comparison). RESULTS: There was no significant difference in motor function, between those born preterm with those born at term, either at 8 or at 12 months of age. In the control group, there was significant association (r=0.67; p=0.004) between movement at 8 months and mobility skills at 12 months. In the risk group, there was significant relationship between skills and independence in mobility, at 12 months corrected age (r=0.80; p=0.0001). CONCLUSION: Preterm born children, without other disorders and with age correction, might show a similar motor development as those born at term. The path for the acquisition of motor abilities in preterm born children appears to differ among those infants. 相似文献
79.
Radiological findings in an unusual osteosarcoma in the maxilla 总被引:1,自引:0,他引:1
An unusual case of osteosarcoma of the maxilla, which was initially diagnosed as fibrous dysplasia on the basis of the clinical CT and histopathological findings, is presented. However, panoramic and periapical radiography suggested a malignant neoplasm. After surgery, the tumor was diagnosed histopathologically as a low-grade osteosarcoma. We conclude that panoramic and periapical radiographs are important adjuncts and should be included in any investigation of the jaws where CT scanning is unable to differentiate between osteosarcoma and fibrous dysplasia. 相似文献
80.
Laércio Marques da Luz Neto Flávia Maria Nassar de Vasconcelos Jacqueline Elineuza da Silva Tiago Coimbra Costa Pinto Éverton Botelho Sougey Rosana Christine Cavalcanti Ximenes 《Jornal de pediatria》2019,95(1):18-26