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排序方式: 共有7301条查询结果,搜索用时 218 毫秒
171.
Opinion statement
相似文献
– | Under most circumstances, the goal of treatment of pulmonary embolism is the prevention of recurrent embolic events, achieved through conventional anticoagulant therapy with unfractionated heparin or a low molecular weight heparin, followed by warfarin therapy for a minimum of 6 months. |
– | When acute pulmonary embolism is associated with significant right ventricular dysfunction or systemic hypotension, more aggressive intervention may be warranted. Under these circumstances, potential interventions include thrombolytic therapy (either systemic or catheterdirected), placement of an inferior vena caval filter, catheter-based embolectomy, or surgical embolectomy. |
– | Chronic thromboembolic pulmonary hypertension may develop in a small minority of patients who survive an acute, massive embolic event or who have suffered recurrent thromboembolic events. Due to the fixed nature of the pulmonary vascular obstruction, vasodilator therapy has proven far less effective in chronic thromboembolic disease than it has in primary pulmonary hypertension and other secondary forms of pulmonary hypertension. Correction of hypoxemia and volume overload and the prevention of recurrent embolic events are essential. Definitive therapy, however, requires surgical intervention to remove the chronic thromboembolic obstruction and to restore patency of the pulmonary vascular bed. |
172.
Exacerbation of hypertension by nonsteroidal anti-inflammatory drugs in hypertensive patients remains controversial among
physicians and investigators. Because of the many differences among studies of oral nonsteroidal anti-inflammatory drugs and
blood pressure control in patients with hypertension, the authors critically evaluated the published clinical evidence on
this subject using standardized methodologic criferia. A search of the literature from 1965 to 1986 identified 31 relevant
studies, of which only eight were double-blind randomized controlled trials that provided the most clinically useful information.
Of these eight best-designed studies, five of the six that studied indomethacin concluded that it may interfere with antihypertensive
effectiveness in selected patients with treated, stable hypertension. The remaining double-blind randomized studies included
comparisons of other nonsteroidal anti-inflammatory drugs. Their limited results suggest that sulindac is less likely than
piroxicam, naproxen or indomethacin to cause an attenuation of antihypertensive therapy. More research on this subject is
needed, with greater attention to methodologic details and identification of predisposing risk factors for impairment of blood
pressure control by nonsteroidal anti-inflammatory drugs.
Received from the Department of Internal Medicine, University of Cincinnati, Medical Center, and the Department of Pharmacy.
University Hospital, Cincinnati, Ohio. 相似文献
173.
Herman P Pugliese V D'Albuquerque LA Saad WA Pinotti HW 《Arquivos de gastroenterologia》1998,35(3):186-189
Biliary cystadenoma is a rare benign disease, with unknown etiology and is considered as a pre-malignant lesion. Until 1988, only 71 cases had been reported. The authors present three cases and discuss the diagnosis and treatment and the disease. 相似文献
174.
Raffaele Ferrari Saad Dawoodi Merrill Raju Avinash Thumma Linda S. Hynan Shirin Hejazi Maasumi Joan S. Reisch Sid O'Bryant Marjorie Jenkins Robert Barber Parastoo Momeni 《Neurobiology of aging》2013
Women are at a 2-fold risk of developing late-onset Alzheimer's disease (AD) (onset at 65 years of age or older) compared with men. During perimenopausal years, women undergo hormonal changes that are accompanied by metabolic, cardiovascular, and inflammatory changes. These all together have been suggested as risk factors for late-onset AD. However, not all perimenopausal women develop AD; we hypothesize that certain genetic factors might underlie the increased susceptibility for developing AD in postmenopausal women. We investigated the Androgen Receptor gene (AR) in a clinical cohort of male and female AD patients and normal control subjects by sequencing all coding exons and evaluating the length and distribution of the CAG repeat in exon 1. We could not establish a correlation between the repeat length, sex, and the disease status, nor did we identify possible pathogenic variants. AR is located on the X chromosome; to assess its role in AD, X-inactivation patterns will need to be studied to directly correlate the actual expressed repeat length to a possible sex-specific phenotypic effect. 相似文献
175.
Anna Kolecka Kantarawee Khayhan Marizeth Groenewald Bart Theelen Michael Arabatzis Aristea Velegraki Markus Kostrzewa Mihai Mares Saad J. Taj-Aldeen Teun Boekhout 《Journal of clinical microbiology》2013,51(8):2491-2500
Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) was used for an extensive identification study of arthroconidial yeasts, using 85 reference strains from the CBS-KNAW yeast collection and 134 clinical isolates collected from medical centers in Qatar, Greece, and Romania. The test set included 72 strains of ascomycetous yeasts (Galactomyces, Geotrichum, Saprochaete, and Magnusiomyces spp.) and 147 strains of basidiomycetous yeasts (Trichosporon and Guehomyces spp.). With minimal preparation time, MALDI-TOF MS proved to be an excellent diagnostic tool that provided reliable identification of most (98%) of the tested strains to the species level, with good discriminatory power. The majority of strains were correctly identified at the species level with good scores (>2.0) and seven of the tested strains with log score values between 1.7 and 2.0. The MALDI-TOF MS results obtained were consistent with validated internal transcribed spacer (ITS) and/or large subunit (LSU) ribosomal DNA sequencing results. Expanding the mass spectrum database by increasing the number of reference strains for closely related species, including those of nonclinical origin, should enhance the usefulness of MALDI-TOF MS-based diagnostic analysis of these arthroconidial fungi in medical and other laboratories. 相似文献
176.
177.
Samar Samir Youssef Asmaa Mostafa Abd El-Aal Amr Saad Moataza Hassan Omran Taher El Zanaty Sameh Mohamed Seif 《Disease markers》2013,35(5):431-437
Introduction. Hepatitis C virus (HCV) infection affects almost 3% of the world''s population with the highest prevalence in Egypt (15%). The standard therapy; pegylated interferon (PEG-IFN) and ribavirin, is effective in only 60% of Egyptian patients; moreover it is costly, prolonged, and has severe side effects, so prediction of response is essential to reduce burden of unfavorable treatment. Several viral and host factors have been proved to affect response to the treatment PEG-IFN and ribavirin; the strongest of them is polymorphisms near IL28B; nonetheless, nonresponse in patients with favorable IL28B is still unexplained, which implies the importance of studying other immunological factors that may correlate with response. Interleukin 12 (IL-12) is one of the most important proinflammatory cytokine presented with the initiation of immune response, determining Th1 and Th2 differentiation. A functional single nucleotide polymorphism (A/C) at the 3′ untranslated region (3′UTR) at position 1188 (NCBI SNP database no 3212227) was reported to be associated with responding more efficiently to antiviral combination therapy in HCV genotype 1 infected patients. The present study aims to evaluate association between this polymorphism with fibrosis stages, necroinflammation activity, response to the combined therapy, and gender in Egyptian HCV genotype 4. Material and Methods. A total of 133 Egyptian chronic HCV (CHCV) patients were treated with IFN/RBV and were followed up. IL12B 1188 A/C genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PRC-RFLP) analysis. Results. A nonsignificant trend for higher sustained virological response (SVR) was observed in patients homozygote for IL12B 1188 A/C SNP CC genotype (69% SVR versus 30.8% NR) only but not in AC and AA genotypes. No association was detected between IL12B 1188 A/C polymorphism and less severe fibrosis or less liver activity. By stratification of response according to gender genotype, a significant difference in response between males and females was seen among AA genotype carriers only due to high number of non responder females. Conclusion. IL12B CC genotype appears to have some influence on SVR achievement but not on severe fibrosis and severe necroinflamation activity. Females carrying A/A genotype of IL12B 1188 A/C SNP achieve less SVR than those carrying AC and CC genotypes. 相似文献
178.
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
179.
Solriamfetol for Excessive Daytime Sleepiness in Parkinson's Disease: Phase 2 Proof-of-Concept Trial
180.
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