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51.
Damaris J. Rohsenow Jonathan Howland Luisa Alvarez Kerrie Nelson Breanne Langlois Joris C. Verster Heather Sherrard J. Todd Arnedt 《Addictive behaviors》2014
Aims
Beliefs about the effects of mixing caffeine and alcohol on hangover or sleep may play a role in motivation to consume these mixtures; therefore, information is needed about actual effects. We investigated whether intoxication with caffeinated vs. non-caffeinated beer differentially affected perceived sleep quality, sleepiness, and hangover incidence and severity the next morning.Methods
University students (89%) and recent graduate drinkers were randomized to receive: (1) beer with the equivalent of 69 mg caffeine/12 oz glass of regular beer (n = 28) or (2) beer without caffeine (n = 36), in sufficient quantity to attain a BrAC of 0.12 g%. After an 8-h supervised sleep period, participants completed measures of hangover, sleep quality, sleep latency and time asleep, and sleepiness.Results
While caffeinated beer improved perceived sleep quality, effect sizes were greater for morning alertness than for quality while sleeping, with no effect on sleep latency or total sleep time. No effects were seen on hangover incidence or severity.Conclusions
Mixing caffeine and alcohol does not significantly impair amount of sleep or sleep latency, hangover, or sleepiness the morning after drinking to intoxication in this population. 相似文献52.
53.
The principal neutralization determinant of simian immunodeficiency virus differs from that of human immunodeficiency virus type 1. 总被引:16,自引:0,他引:16
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K Javaherian A J Langlois S Schmidt M Kaufmann N Cates J P Langedijk R H Meloen R C Desrosiers D P Burns D P Bolognesi et al. 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(4):1418-1422
To identify the principal neutralization determinant (PND) of simian immunodeficiency virus (SIV), antisera were generated using recombinant gp110 [the SIV analog of the human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein, gp120], gp140, several large recombinant and proteolytic envelope fragments, and synthetic peptides of the SIVmac251 isolate. When purified under conditions that retain its native structure, gp110 bound CD4 and elicited antisera that neutralized SIVmac251 with high titer. Native gp110 also completely inhibited neutralizing antibody in sera from SIVmac251-infected macaques. In contrast, denatured gp110 and gp140, large envelope fragments, and synthetic peptides (including peptides analogous to the HIV-1 PND) elicited very low or undetectable neutralizing antibody titers and did not inhibit neutralizing antibody in infected macaque sera. Enzymatically deglycosylated gp110 efficiently absorbed neutralizing antibodies from macaque sera, showing that neutralizing antibodies primarily bind the protein backbone. A 45-kDa protease digest product, mapping to the carboxyl-terminal third of gp110, also completely absorbed neutralizing antibodies from infected macaque sera. These results show that the PND(s) of this SIV isolate depends on the native conformation and that linear peptides corresponding to the V3 loop of SIV envelope, in contrast to that of HIV-1, do not elicit neutralizing antibody. This may affect the usefulness of SIVmac for evaluating HIV-1 envelope vaccine approaches that rely on eliciting neutralizing antibody. 相似文献
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56.
Tobias Tritschler Nomie Kraaijpoel Philippe Girard Harry R. Büller Nicole Langlois Marc Righini Sam Schulman Annelise Segers Grgoire Le Gal 《Journal of thrombosis and haemostasis》2020,18(6):1495-1500
Pulmonary embolism (PE)‐related death is often a component of the primary outcome in venous thromboembolism (VTE) clinical studies. Definitions for PE‐related death vary widely, which may lead to biased risk estimates of clinical outcomes, thereby affecting both internal and external validity of study results. We here provide a standardized definition of PE‐related death and propose guidance for classification and reporting of the cause of death for clinical studies in VTE. The proposal was developed in a four‐step process, including a systematic review of definitions used for PE‐related death in previous studies, two subsequent surveys with VTE experts, and meetings held within the Scientific and Standardization Committee (SSC) working group until consensus on the proposal was reached. The proposed classification comprises three categories: Category A: PE‐related death, category B: undetermined cause of death, and category C: cause of death other than PE. Category A includes A1: autopsy‐confirmed PE in the absence of another more likely cause of death; A2: objectively confirmed PE before death in the absence of another more likely cause of death; and A3: PE is not objectively confirmed, but is most likely the main cause of death. Category B includes B1: cause of death is undetermined, despite available information; and B2: insufficient clinical information available to determine the cause of death. The use of the proposed definition will hopefully improve the accuracy of study outcomes, between‐study comparisons, meta‐analyses, and validity of future clinical VTE studies. 相似文献
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58.
Debono B Proust F Langlois O Clavier E Douvrin F Derrey S Freger P 《Neuro-Chirurgie》2004,50(1):21-32
BACKGROUND AND PURPOSE: The respective roles of endovascular and surgical treatment must be clearly defined in the management of ruptured anterior communicating artery (AcoA) aneurysm. The aim of our study was to report our results, using the aneurysm direction as the main morphological argument to choose between microsurgery and endovascular embolization. Morbidity and mortality, causes of unfavorable outcome and morphological results were also assessed. PATIENTS AND METHODS: Our prospective study included 119 patients: 89 treated by microsurgery and 30 undergoing embolization with Guglielmi Detachable Coils (GDC). When the aneurysm had an anterior direction (fundus of the aneurysm in front of the pericallosal arteries), we attempted microsurgery. If the fundus of the aneurysm was behind the pericallosal arteries, we selected the most adapted procedure after discussion with the neurovascular team, taking into account the physiological status, treatment risk and neck size. Preoperative status of the patients was assessed according to the Hunt and Hess (HH) classification. Cerebral CT-scan and angiograms were routinely performed after treatment to determine causes of unfavorable outcome (GOS>1) and the morphological results. RESULT: Overall clinical outcome was excellent (GOS1) for 63.0% of patients, good (GOS2) for 10.1%, fair (GOS3) for 13.4%, poor (GOS4) for 2.5%. The mortality rate was 10.9%. Among the 82 patients in good preoperative grade (HHIII), 8 (21.6%) achieved an excellent outcome. However permanent morbidity or death occurred in 15 patients (78.4%). Permanent disability and death were related to initial subarachnoid hemorrhage and were observed 21.3% of patients in the microsurgical group and 30.0% in the endovascular group [Fisher's Exact Test; p=0.33]. Procedure-related permanent disability and death rates were 9.0% for the microsurgical group and 23.3% for the endovascular group (p=0.06) respectively. In the microsurgical group, the only morphologic characteristic which significantly correlated with the occurrence of vessel occlusion was the fundus direction (p=0.03). The difference between endovascular and microsurgical procedures in the achievement of complete occlusion was considered significant (p=0.04). CONCLUSION: In our experience, the direction of the aneurysm was the main morphological criterion in choosing between microsurgery or endovascular procedure for the treatment of AcoA aneurysm. We propose that microsurgical clipping should be preferred for AcoA aneurysms with anterior direction, and depending on morphological criteria, endovascular packing for those with posterior direction. 相似文献
59.
Langlois RG Trebes JE Dalmasso EA Ying Y Davies RW Curzi MP Colston BW Turteltaub KW Perkins J Chromy BA Choi MW Murphy GA Fitch JP McCutchen-Maloney SL 《American journal of nephrology》2004,24(2):268-274
BACKGROUND: Serum protein profiling patterns can reflect the pathological state of a patient and therefore may be useful for clinical diagnostics. Here, we present results from a pilot study of proteomic expression patterns in hemodialysis patients designed to evaluate the range of serum proteomic alterations in this population. METHODS: Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to analyze serum obtained from patients on periodic hemodialysis treatment and healthy controls. Serum samples from patients and controls were first fractionated into six eluants on a strong anion exchange column, followed by application to four array chemistries representing cation exchange, anion exchange, metal affinity and hydrophobic surfaces. A total of 144 SELDI-TOF-MS spectra were obtained from each serum sample. RESULTS: The overall profiles of the patient and control samples were consistent and reproducible. However, 30 well-defined protein differences were observed; 15 proteins were elevated and 15 were decreased in patients compared to controls. Serum from 1 patient exhibited novel protein peaks suggesting possible additional changes due to a secondary disease process. CONCLUSION: SELDI-TOF-MS demonstrated consistent serum protein profile differences between patients and controls. Similarity in protein profiles among dialysis patients suggests that patient physiological responses to end-stage renal disease and/or dialysis therapy have a major effect on serum protein profiles. 相似文献
60.
The use of 7-amino actinomycin D in identifying apoptosis: simplicity of use and broad spectrum of application compared with other techniques 总被引:9,自引:5,他引:9
Philpott NJ; Turner AJ; Scopes J; Westby M; Marsh JC; Gordon-Smith EC; Dalgleish AG; Gibson FM 《Blood》1996,87(6):2244-2251
The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states. 相似文献