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91.
The determinations of the amino acid pools, including tryptophan (by fluorescence spectrometry), in the arterial and venous blood of the mother, the arterial and venous blood of the fetus (cord blood), the amniotic fluid and the placenta was done in eight women at the moment of delivery. Only nine amino acids (asp, try, met, phe, ser, cys, lys, gly, thr) were significantly retained and four (arg, glu, pro and glu-NH2) were significantly released by the fetal tissues. In contrast with this behavior most amino acids were retained by the maternal tissue, try, phe and hist showing the highest retention. When the amino acids are grouped as essential and nonessentials, the maternal tissues retained both categories without apparent discrimination, while the fetal tissues retained essential amino acids preferentially. Our results emphasize the importance of the placenta as the regulating system of the fetal milieu under normal conditions. Thus human fetal blood levels of amino acids are patterned after the placental ones and not after the maternal values obtained at the same time. It is apparent that the placenta seems to function as a nonspecific retention filter for outgoing amino acids, but that its function is selective in respect to the release of amino acids into the fetal circulation. 相似文献
92.
Alana E. Sigmund Yixin Fang Matthew Chin Harmony R. Reynolds Leora I. Horwitz Ezra Dweck Eduardo Iturrate 《Mayo Clinic proceedings. Mayo Clinic》2017,92(1):98-105
Objective
To determine the clinical significance of tachycardia in the postoperative period.Patients and Methods
Individuals 18 years or older undergoing hip and knee arthroplasty were included in the study. Two data sets were collected from different time periods: development data set from January 1, 2011, through December 31, 2011, and validation data set from December 1, 2012, through September 1, 2014. We used the development data set to identify the optimal definition of tachycardia with the strongest association with the vascular composite outcome (pulmonary embolism and myocardial necrosis and infarction). The predictive value of this definition was assessed in the validation data set for each outcome of interest, pulmonary embolism, myocardial necrosis and infarction, and infection using multiple logistic regression to control for known risk factors.Results
In 1755 patients in the development data set, a maximum heart rate (HR) greater than 110 beats/min was found to be the best cutoff as a correlate of the composite vascular outcome. Of the 4621 patients who underwent arthroplasty in the validation data set, 40 (0.9%) had pulmonary embolism. The maximum HR greater than 110 beats/min had an odds ratio (OR) of 9.39 (95% CI, 4.67-18.87; sensitivity, 72.5%; specificity, 78.0%; positive predictive value, 2.8%; negative predictive value, 99.7%) for pulmonary embolism. Ninety-seven patients (2.1%) had myocardial necrosis (elevated troponin). The maximum HR greater than 110 beats/min had an OR of 4.71 (95% CI, 3.06-7.24; sensitivity, 47.4%; specificity, 78.1%; positive predictive value, 4.4%; negative predictive value, 98.6%) for this outcome. Thirteen (.3%) patients had myocardial infarction according to our predetermined definition, and the maximum HR greater than 110 beats/min had an OR of 1.72 (95% CI, 0.47-6.27).Conclusion
Postoperative tachycardia within the first 4 days of surgery should not be dismissed as a postoperative variation in HR, but may precede clinically significant adverse outcomes. 相似文献93.
C Gutiérrez J Vila C Garcia-Sala J Velázquez M Otero M Santos S Ruíz-Company M Gobernado 《Journal of pediatric surgery》1987,22(9):865-868
This is a prospective and randomized study of 100 patients with acute appendicitis who were less than 10 years old, in which four different antibiotic regimens commonly in use against gram-negative and anaerobic bacteria were compared in terms of postoperative septic complications. The antibiotics were begun immediately preoperatively and continued for five days. Ten percent of the patients developed infection complications, with 4% requiring further surgery. The best results were obtained with cefoxitin (4% of infection), metronidazole plus amikacin and latamoxef (8%), while the regimen of clindamycin plus amikacin was associated with the greatest number of complications (20%). On analyzing the main microbiologic findings of the study, we conclude that some sort of antibiotic treatment is indicated in all types of appendicitis, due to the occult presence of bacteria in the peritoneal cavity, even without clinical evidence of gangrene or perforation. Further, we emphasize the significance of Streptococcus faecalis as being responsible, along with Escherichia coli and Bacteroides fragilis, for serious postoperative complications. 相似文献
94.
D. N. Velázquez Martínez M. Valencia Flores M. López Cabrera J. E. Villarreal 《Psychopharmacology》1995,117(1):91-101
Indorenate (TR3369, 5-methoxytryptamine b-methylcarboxylate HCl) is a 5-HT1-like receptor agonist with hypotensive activity. Here, we describe that indorenate also decreases food intake (ED50 26.1 mg/kg) without an appreciable effect in water intake (the estimated ED50 for water was 589.8 mg/kg). The anorectic activity of indorenate was compared to the effects of amphetamine and other serotonin agonists; the effect of indorenate was smaller than those of the other compounds; however, the effect of indorenate was specific to food, whereas all the other drugs also produced significant decrements in water intake. The serotonin antagonists cinanserin, cyproheptadine, methergoline and methysergide effectively prevented the decrease in food intake produced by indorenate and fenfluramine. Haloperidol, a dopaminergic antagonist, was ineffective in preventing the effect of indorenate although it prevented the anorectic effect of amphetamine. The present results suggest the participation of serotoninergic, but not dopaminergic mechanisms, in the decrease in food intake produced by indorenate. 相似文献
95.
Rosen LN 《Violence against women》2007,13(9):945-960
This study involves a test of the cultural spillover hypothesis through a state-level analysis of the relationship between rape rates and the proportion of military personnel in the population. A statistically significant correlation not predicted by this hypothesis was found between rape rates and the proportion of Air Force personnel in the population. Further exploration revealed that this was largely because of the high correlation between the Air Force and the Indian population. Multivariate analyses revealed that the proportion of Indian women in the population was the main predictor of rape rates. Per capita alcohol consumption was also found to be positively correlated with both rape rates and Air Force personnel but was not significantly related to rape in the multivariate analysis. 相似文献
96.
Baliharová V Velík J Fimanová K Lamka J Szotáková B Savlík M Skálová L 《Pharmacological reports : PR》2005,57(1):97-106
Cytochromes P450 (CYP) belong to the most important biotransformation enzymes, therefore, their inhibition may lead to serious pharmacological and toxicological consequences. Albendazole (ABZ) is a benzimidazole anthelmintic widely used in human and veterinary medicine. The effects of ABZ on CYP were investigated on the rat (Rattus norvergicus) and mouflon (Ovis musimon) hepatic microsomes. Besides ABZ, its two main metabolites (albendazole sulfoxide, ABZSO, and albendazole sulfone, ABZSOO) were tested to clarify which compound is responsible for the inhibitory effect. After preincubation of microsomes with the benzimidazoles (1, 5 and 25 microM), CYP activities, ethoxyresorufin O-deethylase (EROD) and benzyloxyresorufin O-dearylase activities were measured. The results showed that both ABZ and ABZSO, but not ABZSOO, exhibited significant potency to inhibit CYP activities measured in both tested species. Since ABZ as well as ABZSO are known inducers of EROD activity, our results clearly demonstrate that the drug can act as inducer and also as inhibitor of the same enzyme. In in vitro studies the CYP inhibition may mask the CYP induction. The extent of inhibition observed in mouflon was significantly higher than in rat. This finding emphasizes the importance of performance of inhibition studies in target animal species. Possible consequences of CYP inhibition should be taken into account during the anthelmintic therapy of mouflons with ABZ. 相似文献
97.
Karen L Smith Rahul R Rao Clara Velázquez-Sánchez Marta Valenza Chiara Giuliano Barry J Everitt Valentina Sabino Pietro Cottone 《Neuropsychopharmacology》2015,40(5):1163-1171
Binge-eating disorder is characterized by excessive, uncontrollable consumption of palatable food within brief periods of time. The role of the glutamatergic N-methyl-D-aspartate (NMDA) receptor system in hedonic feeding is poorly understood. The aim of this study was to characterize the effects of the uncompetitive NMDA receptor antagonist memantine on palatable food-induced behavioral adaptations using a rat model, which mimics the characteristic symptomatology observed in binge-eating disorder. For this purpose, we allowed male Wistar rats to respond to obtain a highly palatable, sugary diet (Palatable group) or a regular chow diet (Chow control group), for 1 h a day, under a fixed-ratio 1 (FR1) schedule of reinforcement. Upon stabilization of food responding, we tested the effects of memantine on the Chow and Palatable food groups'' intake. Then, we tested the effects of memantine on food-seeking behavior, under a second-order schedule of reinforcement. Furthermore, we investigated the effects of memantine on the intake of food when it was offered in an aversive, bright compartment of a light/dark conflict test. Finally, we evaluated the effects of memantine on FR1 responding for food, when microinfused into the nucleus accumbens (NAcc) shell or core. Memantine dose-dependently decreased binge-like eating and fully blocked food-seeking behavior and compulsive eating, selectively in the Palatable food group. The drug treatment did not affect performance of the control Chow food group. Finally, intra-NAcc shell, but not core, microinfusion of memantine decreased binge-like eating. Together, these findings substantiate a role of memantine as a potential pharmacological treatment for binge-eating disorder. 相似文献
98.
5‐HT2B Receptor Antagonists Reduce Nerve Injury‐Induced Tactile Allodynia and Expression of 5‐HT2B Receptors 下载免费PDF全文
Jorge B. Pineda‐Farias Isabel Velázquez‐Lagunas Paulino Barragán‐Iglesias Claudia Cervantes‐Durán Vinicio Granados‐Soto 《Drug development research》2015,76(1):31-39
Preclinical Research |
99.
Analysis of cytotoxic effects of silver nanoclusters on human peripheral blood mononuclear cells ‘in vitro’ 下载免费PDF全文
Sandra Teresa Orta‐García Germán Plascencia‐Villa Angeles Catalina Ochoa‐Martínez Tania Ruiz‐Vera Francisco Javier Pérez‐Vázquez J Jesús Velázquez‐Salazar Miguel José Yacamán Hugo Ricardo Navarro‐Contreras Iván N. Pérez‐Maldonado 《Journal of applied toxicology : JAT》2015,35(10):1189-1199
The antimicrobial properties of silver nanoparticles (AgNPs) have made these particles one of the most used nanomaterials in consumer products. Therefore, an understanding of the interactions (unwanted toxicity) between nanoparticles and human cells is of significant interest. The aim of this study was to assess the in vitro cytotoxicity effects of silver nanoclusters (AgNC, < 2 nm diameter) on peripheral blood mononuclear cells (PBMC). Using flow cytometry and comet assay methods, we demonstrate that exposure of PBMC to AgNC induced intracellular reactive oxygen species (ROS) generation, DNA damage and apoptosis at 3, 6 and 12 h, with a dose‐dependent response (0.1, 1, 3, 5 and 30 µg ml–1). Advanced electron microscopy imaging of complete and ultrathin‐sections of PBMC confirmed the cytotoxic effects and cell damage caused by AgNC. The present study showed that AgNC produced without coating agents induced significant cytotoxic effects on PBMC owing to their high aspect ratio and active surface area, even at much lower concentrations (<1 µg ml–1) than those applied in previous studies, resembling what would occur under real exposure conditions to nanosilver‐functionalized consumer products. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
100.
Effect of Serenoa Repens on Oxidative Stress,Inflammatory and Growth Factors in Obese Wistar Rats with Benign Prostatic Hyperplasia 下载免费PDF全文
Juventino III Colado‐Velázquez Patrick Mailloux‐Salinas JML Medina‐Contreras David Cruz‐Robles Guadalupe Bravo 《Phytotherapy research : PTR》2015,29(10):1525-1531
Serenoa repens has been widely used to treat benign prostatic hyperplasia and lower urinary tract symptoms; however, most of the studies have been conducted in individuals with normal weight and not obese. In this study, the effects of a lipidic extract of S. repens, in markers of oxidative stress, inflammation, and growth factors, in obese rats with testosterone‐induced prostatic hyperplasia, were investigated. Total nitrites, malondialdehyde, total glutathione, superoxide dismutase (SOD), and catalase activity were measured; in addition, assays for inflammatory cytokines TNF‐α, IL‐1β, IL‐6 and the growth factors basic fibroblast growth factor (FGFb) and vascular endothelial growth factor (VEGF) were performed. The obese rats had a higher prostate weight compared with controls. S. repens significantly decreased prostate weight, total nitrites, and malondialdehyde; improved total glutathione, SOD, and catalase activity; and significantly reduced inflammatory (TNF‐α, IL‐1β and IL‐6) and growth factors (VEGF and FGFb). S. repens showed high antioxidant and antiinflammatory activity in obese rats, suggesting that their use could be beneficial in the treatment of benign prostatic hyperplasia. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献