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991.
Farel CE Chaitt DG Hahn BK Tavel JA Kovacs JA Polis MA Masur H Follmann DA Lane HC Davey RT 《Blood》2004,103(9):3282-3286
Studies establishing that intermittent subcutaneous interleukin-2 (IL-2) therapy can lead to substantial CD4 cell increases in many HIV-infected patients have generally been of limited duration. We studied 77 patients participating in active longitudinal studies of subcutaneous IL-2 therapy at our center in order to determine the long-term feasibility of this approach. Following initial induction, patients in each trial were eligible to receive intermittent 5-day cycles of subcutaneous IL-2 treatment at individualized doses and frequencies capable of maintaining CD4 counts at postinduction levels. The mean duration of study participation to date is 5.9 years (range, 1.0-9.3 years). Mean baseline CD4 cell count and CD4 percent values of 0.521 x 10(9)/L (521 cells/microL) and 27% have risen to 1.005 x 10(9)/L (1005 cells/microL) and 38%, respectively, at 90 months. The mean number of subcutaneous IL-2 cycles required to achieve and maintain these increases was 10 cycles (range, 3-29 cycles), and the current mean interval of cycling required to maintain these elevations is 39 months (median, 35 months; range, 2-91 months). We conclude that subcutaneous IL-2 therapy is capable of maintaining CD4 cell increases for an extended period using a remarkably low frequency of intermittent cycling. These observations may contribute to patients' acceptance of subcutaneous IL-2 as a favorable long-term treatment strategy. 相似文献
992.
Dingli D Kyle RA Rajkumar SV Nowakowski GS Larson DR Bida JP Gertz MA Therneau TM Melton LJ Dispenzieri A Katzmann JA 《Blood》2006,108(6):1979-1983
An abnormal serum immunoglobulin free light chain (FLC) ratio at diagnosis may identify risk of progression to myeloma in patients with solitary bone plasmacytoma (SBP). In the cohort of 116 patients, 43 have progressed to myeloma, with a median time to progression of 1.8 years. The FLC ratio was determined in all 116 patients on serum collected at time of diagnosis and was abnormal in 54 patients (47%). An abnormal FLC ratio was associated with a higher risk of progression to myeloma (P = .039). The risk of progression at 5 years was 44% in patients with an abnormal serum FLC ratio at diagnosis compared with 26% in those with a normal FLC ratio. One to 2 years following diagnosis, a persistent serum M protein level of 5 g/L (0.5 g/dL) or higher was an additional risk factor for progression. A risk stratification model was constructed using the 2 variables of FLC ratio and M protein level: patients with a normal FLC ratio at baseline and M protein level less than 5 g/L (0.5 g/dL) at 1 to 2 years following diagnosis (low risk, n = 31); with either risk factor abnormal (intermediate risk, n = 26); and with both an abnormal FLC ratio and M protein level of 5 g/L (0.5 g/dL) or higher (high risk, n = 18). The corresponding progression rates at 5 years were significantly different in the low, intermediate, and high groups: 13%, 26%, and 62%, respectively (P < .001). 相似文献
993.
Small-molecule XIAP inhibitors derepress downstream effector caspases and induce apoptosis of acute myeloid leukemia cells 总被引:16,自引:0,他引:16 下载免费PDF全文
Carter BZ Gronda M Wang Z Welsh K Pinilla C Andreeff M Schober WD Nefzi A Pond GR Mawji IA Houghten RA Ostresh J Brandwein J Minden MD Schuh AC Wells RA Messner H Chun K Reed JC Schimmer AD 《Blood》2005,105(10):4043-4050
We tested the effects of small-molecule XIAP antagonists based on a polyphenylurea pharmacophore on cultured acute myelogenous leukemia (AML) cell lines and primary patient samples. X-linked inhibitor of apoptosis protein (XIAP) antagonist N-[(5R)-6-[(anilinocarbonyl)amino]-5-((anilinocarbonyl){[(2R)-1-(4-cyclohexylbutyl)pyrrolidin-2-yl]methyl}amino)hexyl]-N-methyl-N'-phenylurea (1396-12), but not a structurally related control compound, induced apoptosis of primary leukemia samples with a lethal dose (LD50) of less than 10 microM in 16 of 27 (60%) samples. In contrast, XIAP antagonist 1396-12 was not lethal to the normal hematopoietic cells in short-term cytotoxicity assays. Response of primary AML specimens to XIAP inhibitor correlated with XIAP protein levels, with higher levels of XIAP associated with sensitivity. The XIAP antagonist 1396-12 induced activation of downstream caspases 3 and 7 prior to the activation of upstream caspase 8 and caspase 9. Apoptosis induction was also independent of B-cell lymphoma protein-2 (Bcl-2) or caspase 8, indicative of a downstream effect on apoptotic pathways. Thus, polyphenylurea-based XIAP antagonsists directly induce apoptosis of leukemia cells and AML patient samples at low micromolar concentrations through a mechanism of action distinct from conventional chemotherapeutic agents. 相似文献
994.
Alexander Becker Ori Yaslowitz Joseph Dubose Kobi Peleg Yaakov Daskal Adi Givon Israel Trauma Group Boris Kessel 《中华创伤杂志(英文版)》2020,23(3):181-184
Purpose: Pelvic fracture evaluation with abdominopelvic computed tomography (CT) and formal CT cystography for rule out of urine bladder injury have been commonly employed in pediatric trauma patients. The additional delayed imaging required to obtain optimal CT cystography is, however, associated with increased doses of ionizing radiation to pelvic organs and represent a significant risk in the pediatric population for future carcinogenic risk. We hypothesized that avoidance of routine CT cystography among pediatric pelvic fracture victims would not result in an appreciable rate of missed bladder injuries and would aid in mitigating the radiation exposure risk associated with these additional
images.
Methods: A retrospective cohort study involving blunt trauma pelvic fractures among pediatric trauma patients (age<14) between the years 1997 and 2016 was conducted utilizing the Israeli National Trauma Registry. Statistical analysis was performed using SAS statistical software version 9.4 via the tests of Chisquare test and two-sided Fisher''s exact test. A p value of less than 0.05 was considered statistically significant.
Results: A total of 1072 children were identified from the registry for inclusion. Mean age of patients was 7.7 years (range 0-14) and 713 (66.5%) were male. Overall mortality in this population was 4.1% (44/1072). Only 2.1% (23) of pediatric patients with pelvic fractures had bladder injury identified, with just 9 children having intraperitoneal bladder rupture (0.8% of all the patients).
Conclusion: The vast majority of blunt pediatric trauma victims with pelvic fractures do not have urine bladder injuries. Based on our study results we do not recommend the routine utilization of CT cystography in this unique population. 相似文献
995.
Ex vivo development of functional human lymph node and bronchus-associated lymphoid tissue 下载免费PDF全文
Tirouvanziam R Khazaal I N'Sondé V Peyrat MA Lim A de Bentzmann S Fournié JJ Bonneville M Péault B 《Blood》2002,99(7):2483-2489
We introduce a novel in vivo model of human mucosal immunity, based on the implantation of human fetal bronchial mucosa and autologous peribronchial lymph node (PLN) in the severe combined immunodeficiency (SCID) mouse. In the SCID host, human fetal bronchi implanted alone retain macrophages and mast cells but lose T cells. In contrast, fetal bronchi co-implanted with PLN contain, in addition to macrophages and mast cells, numerous T cells and B cells, often clustered in intramucosal bronchus-associated lymphoid tissue (BALT). Functionally, bronchus-PLN cografts are able to mount robust alphabeta and gammadelta T-cell-mediated immune responses to Pseudomonas aeruginosa and 3,4-epoxy-3-methyl-1-butyl-diphosphate challenges. No other autologous lymphoid organ (bone marrow, thymus, liver) allows for BALT development in co-implanted bronchi, which suggests special ontogenetic and functional relations between extramucosal PLN and intramucosal BALT. Overall, the bronchus-PLN cograft appears as a promising model for human bronchial immune development and function. Our study is the first to document long-term ex vivo maintenance of functional human lymph nodes as native appendices to mucosal tissue. Our results, therefore, suggest a simple strategy for developing similar experimental models of human immune function in other mucosae. 相似文献
996.
Adoptive transfer of gene-engineered CD4+ helper T cells induces potent primary and secondary tumor rejection 下载免费PDF全文
Moeller M Haynes NM Kershaw MH Jackson JT Teng MW Street SE Cerutti L Jane SM Trapani JA Smyth MJ Darcy PK 《Blood》2005,106(9):2995-3003
Because CD4+ T cells play a key role in aiding cellular immune responses, we wanted to assess whether increasing numbers of gene-engineered antigen-restricted CD4+ T cells could enhance an antitumor response mediated by similarly gene-engineered CD8+ T cells. In this study, we have used retroviral transduction to generate erbB2-reactive mouse T-cell populations composed of various proportions of CD4+ and CD8+ cells and then determined the antitumor reactivity of these mixtures. Gene-modified CD4+ and CD8+ T cells were shown to specifically secrete Tc1 (T cytotoxic-1) or Tc2 cytokines, proliferate, and lyse erbB2+ tumor targets following antigen ligation in vitro. In adoptive transfer experiments using severe combined immunodeficient (scid) mice, we demonstrated that injection of equivalent numbers of antigen-specific engineered CD8+ and CD4+ T cells led to significant improvement in survival of mice bearing established lung metastases compared with transfer of unfractionated (largely CD8+) engineered T cells. Transferred CD4+ T cells had to be antigen-specific (not just activated) and secrete interferon gamma (IFN-gamma) to potentiate the antitumor effect. Importantly, antitumor responses in these mice correlated with localization and persistence of gene-engineered T cells at the tumor site. Strikingly, mice that survived primary tumor challenge could reject a subsequent rechallenge. Overall, this study has highlighted the therapeutic potential of using combined transfer of antigen-specific gene-modified CD8+ and CD4+ T cells to significantly enhance T-cell adoptive transfer strategies for cancer therapy. 相似文献
997.
Antibody responses to H-Y minor histocompatibility antigens correlate with chronic graft-versus-host disease and disease remission 总被引:7,自引:4,他引:7 下载免费PDF全文
Miklos DB Kim HT Miller KH Guo L Zorn E Lee SJ Hochberg EP Wu CJ Alyea EP Cutler C Ho V Soiffer RJ Antin JH Ritz J 《Blood》2005,105(7):2973-2978
Minor histocompatibility antigens (mHAs) are known targets of donor T cells after allogeneic hematopoietic stem cell transplantation (HSCT). In contrast, B-cell responses to mHAs have not been extensively characterized and the clinical significance of antibodies to mHAs is unknown. We tested 121 patients who underwent HSCT and 134 healthy donors for immunoglobulin G (IgG) antibodies against 5 mHAs encoded by genes on the Y chromosome (DBY, UTY, ZFY, RPS4Y, and EIF1AY). Antibodies to at least one H-Y protein developed in 52% of male patients with female donors compared with 8.7% of male patients with male donors (P < .0001), and in 41.4% of healthy females compared with 7.8% of healthy males (P < .0001). H-Y antibodies develop 4 to 12 months after transplantation and persist for long periods. The clinical significance of H-Y antibodies was characterized in 75 male patients with hematologic malignancies who received stem cells from female donors (F --> M HSCT). The presence of H-Y antibodies correlated with chronic graft-versus-host disease (GVHD) by univariate (odds ratio [OR] = 15.5; P < .0001) and multivariable logistic regression analysis (OR = 56.5; P < .0001). Antibody response to Y-chromosome encoded histocompatibility antigens (H-Y antigens) was also associated with maintenance of disease remission (P < .0001). B cells may provide a new target for immune intervention in chronic GVHD. 相似文献
998.
High-dose immunosuppressive therapy and autologous peripheral blood stem cell transplantation for severe multiple sclerosis 总被引:10,自引:1,他引:10
Nash RA Bowen JD McSweeney PA Pavletic SZ Maravilla KR Park MS Storek J Sullivan KM Al-Omaishi J Corboy JR DiPersio J Georges GE Gooley TA Holmberg LA LeMaistre CF Ryan K Openshaw H Sunderhaus J Storb R Zunt J Kraft GH 《Blood》2003,102(7):2364-2372
There were 26 patients enrolled in a pilot study of high-dose immunosuppressive therapy (HDIT) for severe multiple sclerosis (MS). Median baseline expanded disability status scale (EDSS) was 7.0 (range, 5.0-8.0). HDIT consisted of total body irradiation, cyclophosphamide, and antithymocyte globulin (ATG) and was followed by transplantation of autologous, granulocyte colony-stimulating factor (G-CSF)-mobilized CD34-selected stem cells. Regimen-related toxicities were mild. Because of bladder dysfunction, there were 8 infectious events of the lower urinary tract. One patient died from Epstein-Barr virus (EBV)-related posttransplantation lymphoproliferative disorder (PTLD) associated with a change from horse-derived to rabbit-derived ATG in the HDIT regimen. An engraftment syndrome characterized by noninfectious fever with or without rash developed in 13 of the first 18 patients and was associated in some cases with transient worsening of neurologic symptoms. There were 2 significant adverse neurologic events that occurred, including a flare of MS during mobilization and an episode of irreversible neurologic deterioration after HDIT associated with fever. With a median follow-up of 24 (range, 3-36) months, the Kaplan-Meier estimate of progression (>/= 1.0 point EDSS) at 3 years was 27%. Of 12 patients who had oligoclonal bands in the cerebrospinal fluid at baseline, 9 had persistence after HDIT. After HDIT, 4 patients developed new enhancing lesions on magnetic resonance imaging of the brain. The estimate of survival at 3 years was 91%. Important clinical issues in the use of HDIT and stem cell transplantation for MS were identified; however, modifications of the initial approaches appear to reduce treatment risks. This was a heterogeneous high-risk group, and a phase 3 study is planned to fully assess efficacy. 相似文献
999.
Shalaila S. Haas Linda A. Antonucci Julian Wenzel Anne Ruef Bruno Biagianti Marco Paolini Boris-Stephan Rauchmann Johanna Weiske Joseph Kambeitz Stefan Borgwardt Paolo Brambilla Eva Meisenzahl Raimo K. R. Salokangas Rachel Upthegrove Stephen J. Wood Nikolaos Koutsouleris Lana Kambeitz-Ilankovic 《Neuropsychopharmacology》2021,46(4):828
Two decades of studies suggest that computerized cognitive training (CCT) has an effect on cognitive improvement and the restoration of brain activity. Nevertheless, individual response to CCT remains heterogenous, and the predictive potential of neuroimaging in gauging response to CCT remains unknown. We employed multivariate pattern analysis (MVPA) on whole-brain resting-state functional connectivity (rsFC) to (neuro)monitor clinical outcome defined as psychosis-likeness change after 10-hours of CCT in recent onset psychosis (ROP) patients. Additionally, we investigated if sensory processing (SP) change during CCT is associated with individual psychosis-likeness change and cognitive gains after CCT. 26 ROP patients were divided into maintainers and improvers based on their SP change during CCT. A support vector machine (SVM) classifier separating 56 healthy controls (HC) from 35 ROP patients using rsFC (balanced accuracy of 65.5%, P < 0.01) was built in an independent sample to create a naturalistic model representing the HC-ROP hyperplane. This model was out-of-sample cross-validated in the ROP patients from the CCT trial to assess associations between rsFC pattern change, cognitive gains and SP during CCT. Patients with intact SP threshold at baseline showed improved attention despite psychosis status on the SVM hyperplane at follow-up (p < 0.05). Contrarily, the attentional gains occurred in the ROP patients who showed impaired SP at baseline only if rsfMRI diagnosis status shifted to the healthy-like side of the SVM continuum. Our results reveal the utility of MVPA for elucidating treatment response neuromarkers based on rsFC-SP change and pave the road to more personalized interventions.Subject terms: Predictive markers, Psychosis 相似文献
1000.
Warren Clements Joseph Mathew Mark C. Fitzgerald Jim Koukounaras 《Journal of vascular and interventional radiology : JVIR》2021,32(4):586-592
Patients treated with splenic artery embolization (SAE) >48 hours after a blunt injury for a delayed splenic rupture (DSR) were assessed for the need for a subsequent splenectomy. Thirty-four patients underwent SAE for DSR over 10 years at our level 1 trauma center, performed at a median of 4.5 days after the injury (interquartile range = 5.5), and the patients were followed up for a median of 11 months (interquartile range = 31). There were 3 occurrences of rebleeds, and 2 patients required splenectomy (5.9%). This study showed that treatment with SAE after DSR results in splenic salvage in 94.1% of patients. 相似文献