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51.
Vicência Mara Rodrigues de Lima Claudia Pinto Marques Souza de Oliveira Letícia Yumi Sawada Hermes Vieira Barbeiro Evandro Sobroza de Mello Francisco Garcia Soriano Venancio Avancini Ferreira Alves Stephen H Caldwell Flair José Carrilho 《Liver international》2007,27(2):227-234
BACKGROUND: Oxidative stress plays a role in the pathogenesis of nonalcoholic steatohepatitis (NASH). Yo jyo hen shi ko (YHK) is a complex compound purported to reduce reactive oxygen species (ROS) by blocking the propagation of radical-induced reactions. The aim of this study was to evaluate the role of the effect of YHK in experimental NASH. METHODS: NASH was induced in male ob/ob mice by a high-fat (HF) diet or methionine/choline-deficient (MCD) diet for 4 weeks. YHK-treated animals received YHK solution orally (20 mg/kg/day) in both experimental diets (n=6; each group) while control animals received only vehicle. RESULTS: The MCD and HF groups developed moderate diffuse macrosteatosis, hepatocellular ballooning, and a diffuse inflammatory infiltrate. With the addition of YHK, there was a marked reduction in macrosteatosis in both groups. This was associated with decreased lipoperoxide and reduced glutathione-GSH concentrations as well as reduced serum aminotransferases and improved histological markers of inflammation. These changes were also associated with weight loss in the MCD+YHK group and diminished weight gain in the HF+YHK group. CONCLUSION: YHK therapy blunts the development of macrosteatosis in these models of NASH and significantly reduces markers of oxidative stress. YHK also diminishes weight gain in this obesity prone model. Our findings warrant further study on the mechanisms involved with these effects. 相似文献
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Diesel exhaust particulates affect cell signaling,mucin profiles,and apoptosis in trachea explants of Balb/C mice 下载免费PDF全文
Robson Seriani Mara de Souza Junqueira Alessandra Choqueta de Toledo Milton Arruda Martins Marcelo Seckler Adriano Mesquita Alencar Elnara Marcia Negri Luiz Fernando Ferraz Silva Thaís Mauad Paulo Hilário Nascimento Saldiva Mariangela Macchione 《Environmental toxicology》2015,30(11):1297-1308
Particulate matter from diesel exhaust (DEP) has toxic properties and can activate intracellular signaling pathways and induce metabolic changes. This study was conducted to evaluate the activation of extracellular signal‐regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) and to analyze the mucin profile (acid (AB+), neutral (PAS+), or mixed (AB/PAS+) mucus) and vacuolization (V) of tracheal explants after treatment with 50 or 100 μg/mL DEP for 30 or 60 min. Western blot analyses showed small increases in ERK1/2 and JNK phosphorylation after 30 min of 100 μg/mL DEP treatment compared with the control. An increase in JNK phosphorylation was observed after 60 min of treatment with 50 μg/mL DEP compared with the control. We did not observe any change in the level of ERK1/2 phosphorylation after treatment with 50 μg/mL DEP. Other groups of tracheas were subjected to histological sectioning and stained with periodic acid‐Schiff (PAS) reagent and Alcian Blue (AB). The stained tissue sections were then subjected to morphometric analysis. The results obtained were compared using ANOVA. Treatment with 50 μg/mL DEP for 30 min or 60 min showed a significant increase (p < 0.001) in the amount of acid mucus, a reduction in neutral mucus, a significant reduction in mixed mucus, and greater vacuolization. Our results suggest that compounds found in DEPs are able to activate acid mucus production and enhance vacuolization and cell signaling pathways, which can lead to airway diseases. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1297–1308, 2015. 相似文献
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Valdecira Rodrigues de Jesus Pricila Mara Novais de Oliveira Vivian Mara Gonçalves de Oliveira Azevedo 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(4):304-309
Background
The hammock positioning within the incubators simulates the intrauterine environment, however, there is little evidence of its benefits and possible risks.Objectives
The aim of this study was to assess the effects of hammock positioning on behavioral status, vital signs, and pain in very low birth weight preterm newborns.Methods
This is a quasi-experimental/case series study in which premature infants (<1500 g) were positioned in supine for one hour in a hammock. The preterm newborns were assessed 10 min before, during (2, 20, 40, and 60 min), and 10 min after hammock positioning with the Brazelton Neonatal Behavioral Assessment Scale, vital signs and pain by the Neonatal Facial Coding System.Results
28 preterm infants between 28 and 36 weeks of gestational age were evaluated. Regarding the behavioral state, the preterm newborns progressively evolved to light or deep sleep during hammock positioning. There was a statistically significant reduction of the heart and respiratory rate from 2 to 60th minute in a hammock, which was maintained after the positioning. The oxygen saturation remained within normal values. No changes in pain scores were observed.Conclusion
The hammock positioning can be considered a safe method of positioning that can be used to reduce the stress levels in very low birth weight preterm newborns. We did not observe worsening in either pain or vital signs. 相似文献56.
Simone Mara de Araújo Ferreira Thais de Oliveira Gozzo Marislei Sanches Panobianco Manoel Ant?nio dos Santos Ana Maria de Almeida 《Revista latino-americana de enfermagem》2015,23(1):82-89
AIM:
qualitative study, which aimed to identify the barriers that influence nursing care practices related to the sexuality of women with gynecological and breast cancer.METHODS:
the study was conducted with 16 professionals of the nursing area (nurses, nursing technicians and nursing assistants) from two sectors of a university hospital situated in the state of São Paulo, Brazil. The data was collected using semi-structured, in-depth individual interviews. All the interviews were recorded and the participants'' responses were identified and categorized using Content Analysis.RESULTS:
three major themes were identified. These are as follows: 1) barriers related to the biomedical model; 2) barriers related to institutional dynamics and 3) barriers related to the social interpretations of sexuality.CONCLUSIONS:
the results of this study showed that the systematized inclusion of this issue in nursing care routines requires changes in the health paradigm and in the work dynamic, as well as reflection on the personal values and social interpretations related to the topic. A major challenge is to divest sexuality of the taboos and prejudices which accompany it, as well as to contribute to the nursing team being more aware of the difficulties faced by women with gynaecological and breast cancer. 相似文献57.
Elena Makovac Sarah N Garfinkel Andrea Bassi Barbara Basile Emiliano Macaluso Mara Cercignani Giovanni Calcagnini Eugenio Mattei Daniela Agalliu Pietro Cortelli Carlo Caltagirone Marco Bozzali Hugo Critchley 《Neuropsychopharmacology》2015,40(7):1649-1658
Autonomic nervous system activity is an important component of human emotion. Mental processes influence bodily physiology, which in turn feeds back to influence thoughts and feelings. Afferent cardiovascular signals from arterial baroreceptors in the carotid sinuses are processed within the brain and contribute to this two-way communication with the body. These carotid baroreceptors can be stimulated non-invasively by externally applying focal negative pressure bilaterally to the neck. In an experiment combining functional neuroimaging (fMRI) with carotid stimulation in healthy participants, we tested the hypothesis that manipulating afferent cardiovascular signals alters the central processing of emotional information (fearful and neutral facial expressions). Carotid stimulation, compared with sham stimulation, broadly attenuated activity across cortical and brainstem regions. Modulation of emotional processing was apparent as a significant expression-by-stimulation interaction within left amygdala, where responses during appraisal of fearful faces were selectively reduced by carotid stimulation. Moreover, activity reductions within insula, amygdala, and hippocampus correlated with the degree of stimulation-evoked change in the explicit emotional ratings of fearful faces. Across participants, individual differences in autonomic state (heart rate variability, a proxy measure of autonomic balance toward parasympathetic activity) predicted the extent to which carotid stimulation influenced neural (amygdala) responses during appraisal and subjective rating of fearful faces. Together our results provide mechanistic insight into the visceral component of emotion by identifying the neural substrates mediating cardiovascular influences on the processing of fear signals, potentially implicating central baroreflex mechanisms for anxiolytic treatment targets. 相似文献
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Antonio Gasbarrini Giovanni Addolorato Mara Simoncini Giovanni Gasbarrini Paolo Fantozzi Francesca Mancini Luigi Montanari Mirella Nardini Andrea Ghiselli Cristina Scaccini 《Digestive diseases and sciences》1998,43(6):1332-1338
The relationship between chronic moderate beerconsumption and oxidative stress was studied in rats.Animals were fed three different isocaloric diets forsix weeks: a beercontaining diet (30% w/w), an ethanol-supplemented diet (1.1 g/100 g, thesame as in the beer diet) and an alcohol-free basaldiet. At the end of the feeding period, rats wereanalyzed for plasma and liver oxidative status. Somelivers were isolated and exposed toischemiareperfusion to assess the additional oxidativestress determined by reperfusion. No significantdifferences in plasma antioxidant status were foundamong the three dietary groups. Lipoproteins from the beer group,however, showed a greater propensity to resist lipidperoxidation. Ischemia caused a decrease in liver energyand antioxidant status in all groups. Nevertheless, ATP was lower in the livers of rats exposed tothe ethanol diet. During reperfusion, lipoperoxidationincreased significantly in all groups. However, liversobtained from ethanoltreated rats showed the higher formation of lipoperoxides. Inconclusion, a moderate consumption of beer in awell-balanced diet did not appear to cause oxidativestress in rats; moreover, probably through its minorcomponents, beer could attenuate the oxidative action ofethanol by itself. 相似文献