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61.
Cianciulli A Venturo I Leonardo F Antonaci S Greco C Lopez M Gandolfo G 《Oncology reports》1995,2(6):1021-1025
Thirty-two patients with multiple cancers were evaluated for in vitro sensitivity to mutagens and were compared with normal controls, Mutagen sensitivity was evaluated by exposing lymphocytes to mitomycin-C in vitro and estimating the mitomycin-induced chromosomal gaps and breaks (G/B) and sister chromatid exchanges (SCE) per cell. The results show significant differences between control and patient groups when spontaneous and induced G/B and SCE were evaluated. In addition, establishing the limit of normality for G/B and SCE, among the control group, the examined patients show largely positive levels in respect to both of the parameters used. In this study we discuss the usefulness of mutagen sensitivity as an indirect measure of DNA repair and genetic susceptibility to multiple primary cancers. 相似文献
62.
Pantoni L Leys D Fazekas F Longstreth WT Inzitari D Wallin A Filippi M Scheltens P Erkinjuntti T Hachinski V 《Alzheimer disease and associated disorders》1999,13(Z3):S49-S54
White matter changes are detected with high frequency by neuroimaging techniques in aged subjects with cerebrovascular risk factors or diseases and in cognitively impaired patients. Their direct role in causing cognitive deterioration has not been established, although their frequency is higher in demented subjects than in normal controls, and they are associated with specific cognitive deficits, particularly those related to impairment of frontal lobe functions. The aim of this paper is to critically review the existing knowledge about the role of white matter lesions in cognitive impairment of vascular origin. After reviewing the scarce evidence and the numerous clues suggesting a possible role of white matter lesions in causing mental decline, proposals are advanced about elements that could be a basis for revised criteria for vascular dementia for clinical trials. Finally, some items requiring future joint investigations in the fields of age-related white matter lesions are identified. 相似文献
63.
Emanuele Nicolai Alberto Cuocolo Leonardo Pace Antonio Nappi Pasquale Sullo Stefania Cardei Luigi Argenziano Fiorenzo Squame Peter J. Ell Marco Salvatore 《Journal of nuclear cardiology》1996,3(1):9-17
Background
Exercise and dipyridamole 99mTc-labeled methoxy isobutyl isonitrile (MIBI) myocardial scintigraphy have been widely used for the diagnosis of coronary artery disease (CAD). However, only limited data on adenosine 99mTc-labeled MIBI cardiac imaging are currently available. This study was designed to assess the accuracy of quantitative adenosinerest 99mTc-labeled MIBI tomography in the diagnosis and localization of CAD.Methods and Results
Fifty-seven consecutive patients with suspected CAD who underwent coronary angiography and 22 normal volunteers were studied. All patients underwent 99mTc-labeled MIBI tomography after administration of adenosine (140 μg/kg intravenously for 6 minutes) and at rest. A total of 171 vascular coronary territories were analyzed quantitatively. All patients with CAD (≥50% luminal stenosis) (n=55) had abnormal 99mTc-labeled MIBI tomograms. The normalcy rate was 86% by quantitative analysis. Overall sensitivity, specificity, and diagnostic accuracy for detection of individual stenosed vessels were 84%, 87%, and 85%, respectively. In patients with one-vessel CAD (n=24), sensitivity and diagnostic accuracy in the detection of individual stenosed vessels were significantly (p<0.05) higher compared with patients with multivessel CAD (n=31). Moreover, 75% of patients with one-vessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in only one coronary artery territory, and 74% of patients with multivessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in two or more coronary artery territories. Sensitivity, specificity, and diagnostic accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=18) compared with those with previous myocardial infarction (n=39). In myocardial territories related to noninfarcted areas (n=124), sensitivity and specificity in the detection of stenosed vessels were 75% and 88%. In infarcted areas (n=47), sensitivity and specificity in the detection of stenosed vessels were 98% and 80% (differences not significant vs noninfarcted areas).Conclusions
Adenosine-controlled coronary vasodilation combined with quantitative 99mTc-labeled MIBI tomography is accurate for identifying patients with CAD and localizing individual stenosed coronary arteries. 相似文献64.
Pasquale Sullo Alberto Cuocolo Emanuele Nicolai Stefania Cardei Antonio Nappi Fiorenzo Squame Eugenio M. Covelli Leonardo Pace Marco Salvatore 《European journal of nuclear medicine and molecular imaging》1996,23(6):648-655
The aim of this study was to evaluate the accuracy of quantitative 1-day exercise-rest technetium-99m tetrofosmin tomography in the identification of patients with coronary artery disease (CAD) and in the detection of individual stenosed coronary vessels. Sixty-one patients with suspected CAD who underwent coronary angiography and 13 normal volunteers were studied. All patients were submitted to two i.v. injections of99mTc-tetrofosmin, one at peak exercise (370 MBq) and the other (1110 MBq) at rest 3 h after exercise (images 15–30 min after injection for both studies). All patients with CAD (0% luminal stenosis) (n=50) had an abnormal99mTc-tetrofosmin tomogram. Only one patient without significant coronary narrowing showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the detection of individual stenosed vessels were 77%, 93% and 85%, respectively. Sensitivity and diagnostic accuracy in the identification of individuals stenosed coronary vessels were significantly higher (P<0.05) in patients with single-vessel disease (n=21) than in those with multivessel disease (n=29). Sensitivity, specificity and accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=26) and in those with previous myocardial infarction (n=35). In myocardial territories related to non-infarcted areas (n=128), sensitivity and specificity in the detection of stenosed vessels were 70% and 95%, respectively. In infarcted areas (n=55), sensitivity and specificity in the detection of stenosed vessels were 85% (P=NS vs non-infarcted areas) and 75% (P<0.05 vs non-infarcted areas), respectively. Finally, sensitivity was significantly lower (P<0.05) in vascular territories supplied by vessels with moderate stenosis (50%–75%) than in those supplied by vessels with severe stenosis (>75%). The results of this study demonstrate that quantitative 1-day exercise-rest99mTc-tetrofosmin single-photon emission tomographic imaging is a suitable and accurate technique to identify patients with CAD and to detect individual stenosed coronary vessels. 相似文献
65.
A group of six patients with a marked gastric lymphoid "hyperplasia", two of these with generalised lymphoma and the others suspected for primary gastric lymphoma, were investigated to discriminate between simple reactive hyperplasias and lymphomatous proliferations. Microscopical and ultrastructural examinations were not useful for this purpose but immunological data can give evidence of a two-fold nature of gastric lymphoid hyperplasia. Some cases are without immunological disorders, others are met with peripheral blood signs of immunological alterations similar to those observed in malignant lymphomas and in chronic lymphocytic leukemia. Only these latter cases should, in our opinion, be regarded as primitive gastric lymphomas. 相似文献
66.
The Scandinavian Multi-Infarct Dementia Trial: a double-blind, placebo-controlled trial on nimodipine in multi-infarct dementia 总被引:8,自引:0,他引:8
Pantoni L Bianchi C Beneke M Inzitari D Wallin A Erkinjuntti T 《Journal of the neurological sciences》2000,175(2):116-123
Vascular dementia is a major cause of mental and physical disability in Western countries. Treatment of vascular dementia is currently based on the recognition and control of vascular risk factors, while specific drugs have not been approved yet. The aim of the present multinational, double-blind, placebo-controlled study was to evaluate the safety and efficacy of nimodipine administered for as long as 26 weeks in improving cognition or slowing cognitive deterioration in patients defined as having multi-infarct dementia (DSM-III-R criteria). Two hundred and fifty-nine patients were included (128 nimodipine, 131 placebo), and 251 were available for the intention-to-treat analysis. No significant difference between drug-treated and placebo patients was noted on the Gottfries-Brane-Steen scale score (primary efficacy criterion), the remaining neuropsychological tests (Zahlen-Verbindungs-Test, Fuld-Object-Memory Evaluation, Word Fluency Test, Digit Span, Mini-Mental State Examination), and the functional scales (index of Activity of Daily Living, Instrumental Activity of Daily Living, Rapid Disability Scale, Clinical Dementia Rating), although the majority of changes were in favor of the active drug group. A lower incidence of cerebrovascular and cardiac events was observed in the nimodipine-treated patients in comparison with the placebo group. This study failed to show a significant effect of nimodipine on cognitive, social or global assessments in patients defined as affected by multi-infarct dementia according to the DSM-III-R criteria. A post-hoc analysis (presented in an accompanying paper) suggests that nimodipine may have a favorable effect in the subgroup of patients defined as affected by subcortical (small vessel) vascular dementia. 相似文献
67.
68.
Mariana Borgognone Leonardo M Pérez Cecilia L Basiglio Justina E Ochoa Marcelo G Roma 《Toxicological sciences》2005,83(1):114-125
Hydrophobic bile salts induce either necrosis or apoptosis depending on the severity of the injury caused by them. Since bile salt-induced apoptosis is influenced by Ca2+- and protein kinase-signaling pathways, and both necrosis and apoptosis share common initiating mechanisms, we analyzed whether these signaling cascades also influence bile salt-induced necrosis in isolated rat hepatocytes. Taurochenodeoxycholate (TCDC, 0.25-1.50 mM, 2 h) reduced, in a dose-dependent manner, the percentage of viable hepatocytes, and increased the release of the cytosolic enzyme, lactate dehydrogenase (LDH) and alanine aminotransferase (ALAT), and that of the plasma membrane enzyme, alkaline phosphatase (AP). The PKC inhibitors, H7 (100 microM) and chelerythrine (2.5 microM), both prevented significantly TCDC-induced necrosis. On the contrary, the PKA activator, dibutyryl-cAMP, exacerbated TCDC-induced cell damage in a dose-dependent manner; this effect was more likely due to cAMP-mediated PKA activation, as the PKA inhibitor, KT5720 (1 microM), counteracted this effect. Instead, the intracellular Ca2+ chelator, BAPTA/AM (20 microM), was without effect. TCDC (1 mM) increased lipid peroxidation from 0.7 +/- 0.2 to 7.5 +/- 0.9 nmol of malondialdehyde per mg of protein, p < 0.001; the addition of the free radical scavenger, diphenyl-p-phenylendiamine, completely blocked this increase and prevented significantly TCDC-induced necrosis. PKC inhibition induced only a slight attenuation of TCDC-induced lipid peroxidation. Possible mechanisms accounting for the modulatory effect of signal transduction pathways on TCDC-induced necrosis, including signaling influence on TCDC transport events and TCDC-induced oxidative stress, are discussed. 相似文献
69.
Earl R. Burrell Heather A. Pines Edward Robbie Leonardo Coleman Ryan D. Murphy Kristen L. Hess Peter Anton Pamina M. Gorbach 《AIDS and behavior》2012,16(7):1816-1820
Mobile phone social networking applications such as GRINDR are potential tools for recruitment of men who have sex with men (MSM) for HIV prevention research. Demographics and sexual risk behaviors of men recruited through GRINDR and through traditional media were compared. GRINDR participants were younger (mean age 31 vs. 42, p?<?0.0001), more White identified (44 vs. 30?%, p?<?0.01), and had more sex partners in the previous 14 days (1.88 vs. 1.10, p?<?0.05) than other recruits. Email responses were less successful for enrollment than phone calls (5 vs. 50?%). This approach resulted in successful recruitment of younger and more educated, White identified MSM. 相似文献
70.
Leonardo Manzari Ann M. Burgess Ian S. Curthoys 《European archives of oto-rhino-laryngology》2012,269(2):685-691
Lermoyez syndrome (LS) has been regarded as a variant of Ménière’s disease (MD), but so far there have been very few cases
of LS reported in the literature, so such a conclusion is debatable. Specifying the pattern of auditory and vestibular changes
at attack using objective quantitative measures is important for understanding the mechanism responsible for MD and LS. Here
we report the first objective measures of dynamic otolith function and dynamic semicircular canal function in an LS patient
at the time of the attack as well as at quiescence, documenting the fluctuation in otolith and semicircular canal function
in the patient. The very rapid changes in dynamic vestibular function at the time of the LS attack appear to complement some
of the rapid changes in auditory and vestibular function at the attack in Ménière’s disease, supporting the contention that
LS is a variant of MD. 相似文献