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81.
Roberts DR Ricci R Funke FW Ramsey P Kelley W Carroll JS Ramsey D Borckardt JJ Johnson K George MS 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,181(2):213-220
Temporary immobilization of the leg serves as a useful model for the brain’s adaptive responses to casting, long-term confinement
to bed rest and possibly to trauma. As part of a larger program using TMS to investigate changes associated with bed rest,
we sought to determine whether casting of the leg causes brain excitability changes measurable with TMS, and the time course
of resolution of these changes. In this study, eight adults wore a full leg cast for 10 days. TMS measures of motor cortex
excitability were gathered before the cast was placed, and then immediately after cast removal, and 24 and 48 h later. A control
group did not wear a cast and underwent the same TMS sessions. Significant excitability changes occurred and peaked at 24 h
post cast removal in the TMS experimental group but not the non-casted group. 相似文献
82.
Quintana H Cherlin EA Duesenberg DA Bangs ME Ramsey JL Feldman PD Allen AJ Kelsey DK 《Clinical therapeutics》2007,29(6):1168-1177
BACKGROUND: The primary treatment for attention-deficit/hyperactivity disorder (ADHD) has been psychostimulants. Recently developed nonpsychostimulant treatments have allowed certain patients to switch from a psychostimulant to a nonpsychostimulant. However, the outcomes of such switches have not been systematically studied. OBJECTIVE: The purpose of this pilot study was to assess treatment tolerance and efficacy during a cross-taper transition from methylphenidate or amphetamine to atomoxetine among children and adolescents with ADHD. METHODS: This pilot study was conducted in patients (aged 6-17 years) with incomplete responses (failure to obtain full reduction/elimination of symptoms) or intolerance of adverse events (AEs) during psychostimulant treatment. Patients continued ongoing psychostimulant treatment during the first week of the study. Transition to atomoxetine began by administering atomoxetine 0.5 mg/kg . d plus full-dose psychostimulant for 1 week, followed in the second week by 1.2 mg/kg . d atomoxetine plus half-dose psychostimulant. Patients remained on 1.2 mg/kg . d atomoxetine monotherapy for the remaining 5 weeks. This stepwise transition was enacted due to the difference in pharmacodynamics between the psychostimulants and atomoxetine. Applying a stepwise cross-titration allowed for better control of ADHD symptoms during the intervening period. Change in ADHD symptoms, as measured by the mean change in the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-administered and -scored (ADHDRS-IV-Parent:Inv), was assessed from baseline to end point. RESULTS: Of the 62 subjects enrolled in the study, 39 (62.9%) were diagnosed as ADHD-combined type. Similar proportions were receiving methylphenidate (51.6%) and amphetamine (48.4%). Slightly more wished to switch due to inadequate response (53.2%) than intolerability (46.8%). Nine subjects discontinued at various times during the course of the study (patient or parent/caregiver decision [4], AE [2], protocol violation [2], and lack of efficacy [1]). Mean (SD) ADHDRS-IV-Parent:Inv total scores (n = 59, last-observation-carried-forward) improved significantly from baseline (visit 2) to an end point (32.1 [10.5] vs 22.6 [14.0]; P < 0.001). Of the 58 subjects answering in the atomoxetine monotherapy phase, 38 (65.5%) reported a preference for atomoxetine treatment over their previous psychostimulant. Tolerability results were as follows: 26 (44.1%) of 59 patients reported >or=1 AE, the most common being somnolence (4 [6.8%]), fatigue (3 [5.1%]), decreased appetite (3 [5.1%]), cough (3 [5.1%]), headache (3 [5.1%]), and contact dermatitis (2 [3.4%]). No clinically severe AEs were reported. Both mean (SD) diastolic (2.4 [7.8] mm Hg; P = 0.031) and systolic (2.4 [7.9] mm Hg; P = 0.029) blood pressures increased significantly from baseline to end point. Electrocardiography revealed a significant increase in mean (SD) heart rate (9.2 [11.6] bpm; P < 0.001) and a corresponding decrease in mean (SD) RR interval (-77.8 [98.2] ms; P < 0.001). Statistically significant, but mild, increases in diastolic pressure and heart rate were observed. CONCLUSION: These children and adolescent patients were successfully switched from methylphenidate or amphetamine to atomoxetine treatment, with resulting improvement in ADHD symptom severity from baseline in this pilot study. 相似文献
83.
84.
Emanuel Schwarz Nico J. M. van Beveren Jordan Ramsey F. Markus Leweke Matthias Rothermundt Bernhard Bogerts Johann Steiner Paul C. Guest Sabine Bahn 《Schizophrenia bulletin》2014,40(4):787-795
Schizophrenia is a heterogeneous disorder normally diagnosed using the Diagnostic and Statistical Manual of Mental Disorders criteria. However, these criteria do not necessarily reflect differences in underlying molecular abnormalities of the disorder. Here, we have used multiplexed immunoassay analyses to measure immune molecules, growth factors, and hormones important to schizophrenia in acutely ill antipsychotic-naive patients (n = 180) and matched controls (n = 398). We found that using the resulting molecular profiles, we were capable of separating schizophrenia patients into 2 significantly distinct subgroups with predominant molecular abnormalities in either immune molecules or growth factors and hormones. These molecular profiles were tested using an independent cohort, and this showed the same separation into 2 subgroups. This suggests that distinct abnormalities occur in specific molecular pathways in schizophrenia patients. This may be of relevance for intervention studies that specifically target particular molecular mechanisms and could be a first step to further define the complex schizophrenia syndrome based on molecular profiles.Key words: schizophrenia, subtypes, diagnosis, molecular profiling, immune factors, growth factors 相似文献
85.
Candace H. Feldman Cameron Speyer Rachel Ashby Bonnie L. Bermas Shamik Bhattacharyya Eliza Chakravarty Brendan Everett Elizabeth Ferucci Aimee O. Hersh Francisco M. Marty Joseph F. Merola Rosalind Ramsey‐Goldman Brad H. Rovin Mary Beth Son Laura Tarter Sushrut Waikar Jinoos Yazdany Joel S. Weissman Karen H. Costenbader 《Arthritis care & research》2021,73(1):146-157
86.
Mitchell L. Ramsey Erin Talbert Daniel Ahn Tanios Bekaii-Saab Niharika Badi P. Mark Bloomston Darwin L. Conwell Zobeida Cruz-Monserrate Mary Dillhoff Matthew R. Farren Alice Hinton Somashekar G. Krishna Gregory B. Lesinski Thomas Mace Andrei Manilchuk Anne Noonan Timothy M. Pawlik Priyani V. Rajasekera Phil A. Hart 《Pancreatology》2019,19(1):80-87
Background
Cachexia is a wasting syndrome characterized by involuntary loss of >5% body weight due to depletion of adipose and skeletal muscle mass. In cancer, the pro-inflammatory cytokine interleukin-6 (IL-6) is considered a mediator of cachexia and a potential biomarker, but the relationship between IL-6, weight loss, and cancer stage is unknown. In this study we sought to evaluate IL-6 as a biomarker of cancer cachexia while accounting for disease progression.Methods
We retrospectively studied 136 subjects with biopsy-proven pancreatic ductal adenocarcinoma (PDAC), considering the high prevalence of cachexia is this population. Clinical data were abstracted from subjects in all cancer stages, and plasma IL-6 levels were measured using a multiplex array and a more sensitive ELISA. Data were evaluated with univariate comparisons, including Kaplan-Meier survival curves, and multivariate Cox survival models.Results
On multiplex, a total of 43 (31.4%) subjects had detectable levels of plasma IL-6, while by ELISA all subjects had detectable IL-6 levels. We found that increased plasma IL-6 levels, defined as detectable for multiplex and greater than median for ELISA, were not associated with weight loss at diagnosis, but rather with the presence of metastasis (p?<?0.001 for multiplex and p?=?0.007 for ELISA). Further, while >5% weight loss was not associated with worse survival, increased plasma IL-6 by either methodology was.Conclusion
Circulating IL-6 levels do not correlate with cachexia (when defined by weight loss), but rather with advanced cancer stage. This suggests that IL-6 may mediate wasting, but should not be considered a diagnostic biomarker for PDAC-induced cachexia. 相似文献87.
Rosenfeld M Gibson RL McNamara S Emerson J Burns JL Castile R Hiatt P McCoy K Wilson CB Inglis A Smith A Martin TR Ramsey BW 《Pediatric pulmonology》2001,32(5):356-366
A thorough understanding of the early natural history of cystic fibrosis (CF) lung disease is critical for the development of effective interventions in the youngest patients. We assessed the evolution of pulmonary infection, inflammation, and clinical course among 40 infants over a 2-year period through annual bronchoalveolar lavage (BAL) for culture and measurements of pro- and anti-inflammatory cytokines, semiannual infant pulmonary function testing, and quarterly clinical evaluations. Both the prevalence of CF pathogens and their density in BAL fluid increased with age. Infants had neutrophilic lower airway inflammation and elevated IL-8 concentrations independent of whether CF pathogens were recovered. Total leukocyte and neutrophil densities and IL-8 concentrations increased with density of CF pathogens in BAL fluid, whether the isolated organism was P. aeruginosa or another pathogen. IL-10 concentrations were similar in CF subjects and non-CF historical controls. Infants generally had suboptimal growth (low weight and height percentiles) and obstructive lung disease (decreased expiratory flows and air trapping). Subjects from whom CF pathogens were isolated at > 10(5) cfu/mL had the worst air trapping and lowest Brasfield chest X-ray scores. Our findings provide a foundation for future studies of early intervention in CF lung disease, including antimicrobial and anti-inflammatory therapy. 相似文献
88.
89.
Haley Ramsey Qi Zhang Diane E. Brown David P. Steensma Charles P. Lin Mei X. Wu 《Haematologica》2014,99(2):282-291
Expression of the immediate early response gene X-1 (IEX-1, IER3) is diminished significantly in hematopoietic stem cells in a subgroup of patients with early stage myelodysplastic syndromes, but it is not clear whether the deregulation contributes to the disease. The current study demonstrates increased apoptosis and a concomitant decrease in the number of hematopoietic stem cells lacking this early response gene. Null mutation of the gene also impeded platelet differentiation and shortened a lifespan of red blood cells. When bone marrow cells deficient in the gene were transplanted into wild-type mice, the deficient stem cells produced significantly fewer circulating platelets and red blood cells, despite their enhanced repopulation capability. Moreover, after exposure to a non-myeloablative dose of radiation, absence of the gene predisposed to thrombocytopenia, a significant decline in red blood cells, and dysplastic bone marrow morphology, typical characteristics of myelodysplastic syndromes. These findings highlight a previously unappreciated role for this early response gene in multiple differentiation steps within hematopoiesis, including thrombopoiesis, erythropoiesis and in the regulation of hematopoietic stem cell quiescence. The deficient mice offer a novel model for studying the initiation and progression of myelodysplastic syndromes as well as strategies to prevent this disorder. 相似文献
90.
Ramsey N. Majzoub Chia-Ling Chan Kai K. Ewert Bruno F.B. Silva Keng S. Liang Erica L. Jacovetty Bridget Carragher Clinton S. Potter Cyrus R. Safinya 《Biomaterials》2014
Steric stabilization of cationic liposome–DNA (CL–DNA) complexes is required for in vivo applications such as gene therapy. PEGylation (PEG: poly(ethylene glycol)) of CL–DNA complexes by addition of PEG2000-lipids yields sterically stabilized nanoparticles but strongly reduces their gene delivery efficacy. PEGylation-induced weakening of the electrostatic binding of CL–DNA nanoparticles to cells (leading to reduced uptake) has been considered as a possible cause, but experimental results have been ambiguous. Using quantitative live-cell imaging in vitro, we have investigated cell attachment and uptake of PEGylated CL–DNA nanoparticles with and without a custom synthesized RGD-peptide grafted to the distal ends of PEG2000-lipids. The RGD-tagged nanoparticles exhibit strongly increased cellular attachment as well as uptake compared to nanoparticles without grafted peptide. Transfection efficiency of RGD-tagged PEGylated CL–DNA NPs increases by about an order of magnitude between NPs with low and high membrane charge density (σM; the average charge per unit area of the membrane; controlled by the molar ratio of cationic to neutral lipid), even though imaging data show that uptake of RGD-tagged particles is only slightly enhanced by high σM. This suggests that endosomal escape and, as a result, transfection efficiency of RGD-tagged NPs is facilitated by high σM. We present a model describing the interactions between PEGylated CL–DNA nanoparticles and the anionic cell membrane which shows how the PEG grafting density and membrane charge density affect adhesion of nanoparticles to the cell surface. 相似文献