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91.
M. L. Barjas-Castro M. C. P. Soares R. C. Menezes M. H. M. Carvalho F. F. Costa S. T. O. Saad 《Annals of human biology》2013,40(2):220-224
Background : The Parakanã is a group of Indians with cultural similarities to the extinct Tupi group. They are an isolated native population from East Brazilian Amazon. A number of different O alleles have been found at the blood group ABO locus in populations of several ethnic origins (Caucasians, Blacks, Amerindians). Aim : The present study describes the ABO blood group polymorphism gene of the Parakanã Indians. The Amerindian group was carefully selected for racial background. Subject and methods : The blood group polymorphism was analysed in genomic DNA from 62 Parakanã Indians. We determined the 261G deletion, the T646A and C771T mutations described in O 1variant and the G542A substitution, using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Results : All Amerindians studied were homozygous for the 261G deletion. The frequencies of the T646A and C771T mutations in Parakanãs (0.65) were lower than that observed in Kayapo, Yanomama and Arara Indians (0.91) ( h 2 = 18.24; p-v < 0.001. The G542A substitution in Parakanãs was also lower (0.22) than in other tribes (0.42) ( h 2 = 9.73; p-v = 0.001). Conclusions : The different O alleles including the G542A mutation are not distributed homogeneously among all Amazonian Amerindians. Our results are in agreement with other genetic markers studied previously in Parakanã Indians, whose distinct genetic pattern differs from Europeans and even from other Amerindians. 相似文献
92.
Mohamed Labib Salem Abdel-Aziz A. Zidan Randa Ezz El-Din El-Naggar Mohamed Attia Saad Mohamed El-Shanshory Usama Bakry Mona Zidan 《Human immunology》2021,82(1):36-45
BackgroundRelapse remains a critical challenge in children with acute lymphoblastic leukemia (ALL). The emergence of immunoregulatory cells, including myeloid-derived suppressor cells (MDSCs), and T regulatory (Treg) cells, has been considered one potential mechanism of relapse in children with ALL.AimThis study aimed to address the microRNAs (miRNAs) related to MDSCs and Treg cells and to explore their targeted immunoregulatory pathways.MethodsAffymetrix microarray was used for global miRNA profiling in B-ALL pediatric patients before, during, and after induction of chemotherapy. Bioinformatics analysis was performed on MDSCs and Treg cells-related dysregulated miRNAs, and miR-Pathway analysis was performed to explore their targeted immunoregulatory pathways.Results516 miRNAs were dysregulated in ALL patients as compared to the healthy donor. Among them, 13 miRNAs and 8 miRNAs related to MDSCs and Treg cells, respectively, were common in all patients. Besides, 12 miRNAs were shared between MDSCs and Treg cells; 4 of them were common in all patients. Four immune-related pathways; TNF, TGF-β, FoxO, and Hippo were found implicated.ConclusionOur pilot study concluded certain miRNAs related to MDSCs and Treg cells, these miRNAs were linked to immunoregulatory pathways. Our results open avenues for testing those miRNA as molecular biomarkers for the immunosuppressive tumor microenvironment. 相似文献
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Teik Hin Tan Zanariah Hussein Fathinul Fikri Ahmad Saad Ibrahim Lutfi Shuaib 《Nuclear Medicine and Molecular Imaging》2015,49(2):143-151
Purpose
To evaluate the diagnostic performance of 68Ga-DOTATATE 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT), 18F-FDG PET/CT and 131I-MIBG scintigraphy in the mapping of metastatic pheochromocytoma and paraganglioma.Materials and Methods
Seventeen patients (male = 8, female = 9; age range, 13–68 years) with clinically proven or suspicious metastatic pheochromocytoma or paraganglioma were included in this prospective study. Twelve patients underwent all three modalities, whereas five patients underwent 68Ga-DOTATATE and 131I-MIBG without 18F-FDG. A composite reference standard derived from anatomical and functional imaging findings, along with histopathological information, was used to validate the findings. Results were analysed on a per-patient and on per-lesion basis. Sensitivity and accuracy were assessed using McNemar’s test.Results
On a per-patient basis, 14/17 patients were detected in 68Ga-DOTATATE, 7/17 patients in 131I-MIBG, and 10/12 patients in 18F-FDG. The sensitivity and accuracy of 68Ga-DOTATATE, 131I-MIBG and 18F-FDG were (93.3 %, 94.1 %), (46.7 %, 52.9 %) and (90.9 %, 91.7 %) respectively. On a per-lesion basis, an overall of 472 positive lesions were detected; of which 432/472 were identified by 68Ga-DOTATATE, 74/472 by 131I-MIBG, and 154/300 (patient, n = 12) by 18F-FDG. The sensitivity and accuracy of 68Ga-DOTATATE, 131I-MIBG and 18F-FDG were (91.5 %, 92.6 % p < 0.0001), (15.7 %, 26.0 % p < 0.0001) and (51.3 %, 57.8 % p < 0.0001) respectively. Discordant lesions were demonstrated on 68Ga-DOTATATE, 131I-MIBG and 18F-FDG.Conclusions
Ga-DOTATATE PET/CT shows high diagnostic accuracy than 131I-MIBG scintigraphy and 18F-FDG PET/ CT in mapping metastatic pheochromocytoma and paraganglioma. 相似文献96.
Joseph W. Owen Kathryn J. Fowler Maria B. Doyle Nael E. Saad David C. Linehan William C. Chapman 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2016,18(3):296-303
Background
Hepatobiliary contrast enhanced MRI is known to be the most sensitive imaging modality for detection of colorectal hepatic metastasis. To date no study has investigated the rate of disappearing lesions with gadoxetic acid MR (Eovist/Primovist), or characterized the pathologic response of lesions which disappear on gadoxetic acid MR.Methods
Retrospective review of hepatic resections for colorectal metastases between 01/2008 and 01/2014 was performed to evaluated the rate of disappearance of lesions on gadoxetic acid MR and the rate of complete pathologic response in the lesions that disappear. “Disappearing lesions” were lesions on baseline imaging that were not identifiable on pre-operative Eovist MRI. Complete pathologic response was defined as no viable tumor on pathology or by lack of recurrence within 1 year.Results
In 23 patients, 200 colorectal metastases were identified on baseline imaging. On pre-operative Eovist MR 77 of the 200 lesions (38.5%) were “disappearing” lesions. At surgical pathology or 1 year follow-up imaging, 42 of 77 lesions (55%) demonstrated viable tumor (21) or recurrence (21). Thirty of 77 lesions (39%) were nonviable at pathology (10) or without evidence of recurrence at 1 year (20). 5 lesions were indeterminate.Discussion
Despite disappearance on Eovist MR imaging (the most sensitive available imaging modality), 38.5% of all colorectal metastases disappeared and of those, 55% were viable. 相似文献97.
PURPOSE OF REVIEW: A bacterial cause is found in about half of all severe chronic obstructive pulmonary disease exacerbations. The aim of this review is to discuss recent findings regarding prevalence, risk factors and outcome of severe chronic obstructive pulmonary disease exacerbations caused by multidrug-resistant bacteria. RECENT FINDINGS: According to the results of recent studies, multidrug-resistant bacteria represented a large proportion of bacteria isolated in chronic obstructive pulmonary disease exacerbations. Prior antibiotic treatment, prior endotracheal intubation, long-term inhaled or systemic corticosteroid use and severe impairment of lung function were identified as risk factors for severe chronic obstructive pulmonary disease exacerbations related to multidrug-resistant bacteria. Although the mortality rate was higher in patients with multidrug-resistant bacteria as compared with patients with other bacteria, multidrug resistance was not independently associated with mortality in these patients. Multidrug-resistant bacteria were, however, significantly associated with inappropriate initial antibiotic treatment. Higher rates of subsequent ventilator-associated pneumonia and mortality were found in patients with severe chronic obstructive pulmonary disease exacerbation who received inappropriate initial antibiotic treatment when compared with those who received appropriate treatment. SUMMARY: Further studies should determine whether administration of broad-spectrum antibiotic treatment could improve the outcome of patients with severe chronic obstructive pulmonary disease exacerbation caused by multidrug-resistant bacteria. 相似文献
98.
Arterial vasodilatation was obtained by a slow injection of nicardipine (0.1 microgram/20 min) to normotensive Long Evans rats. Reflex tachycardia was a consequence of a sympathetic activation as labetalol injected prior to nicardipine prevented the calcium antagonist-induced heart rate changes. The slope of the mean blood pressure (mmHg) - heart period (msec) curve was reproducible after a 75 min interval. This index of baroreflex sensitivity was calculated before and after a transient cerebral ischemia. Hemispheric ischemia was induced by electrocauterization of the vertebral arteries and a transient occlusion of the common carotid arteries for 10 min. Brainstem perfusion was maintained with this protocol. The second dose of nicardipine was injected 15 min after recirculation. The tachycardic response to the vasodilatation was markedly reduced after ischemia (1st slope: 0.48 +/- 0.05 msec/mmHg, 2nd slope: 0.12 +/- 0.05 msec/mmHg, n = 12, p less than 0.001, paired t test). We conclude that nicardipine injection is applicable to the study of baroreflex sensitivity in rats. The impairment of baroreflex sensitivity after a transient hemispheric ischemia could reflect a hemispheric interference with brainstem cardiovascular centres involved in the baroreceptor-heart rate reflex. 相似文献
99.
Bone Marrow Assessment in Asymptomatic IgM Monoclonal Gammopathies – Reply to Varettoni et al 下载免费PDF全文
Roger G. Owen Guy Pratt Rebecca L. Auer Rita Flatley Charalampia Kyriakou Michael P. Lunn Francis Matthey Helen McCarthy Feargal P. McNicholl Saad M. Rassam Simon D. Wagner Matthew Streetly Shirley D'Sa the British Committee for Standards in Haematology 《British journal of haematology》2015,168(2):302-303