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61.
Pablo C. B. Lollo Carolina S. Moura Priscila N. Morato Jaime Amaya-Farfan 《Journal of Sports Science and Medicine》2013,12(3):461-466
Running on a horizontal plane is known to increase the concentration of the stress biomarker heat-shock protein (HSP), but no comparison of the expression of HSP70 has yet been established between the uphill (predominantly concentric) and downhill (predominantly eccentric) muscle contractions exercise. The objective of the study was to investigate the relationships between eccentric and concentric contractions on the HSP70 response of the lung, kidney, gastrocnemius, soleus and heart. Twenty-four male Wistar weanling rats were divided into four groups: non-exercised and three different grades of treadmill exercise groups: horizontal, uphill (+7%) and downhill (-7% of inclination). At the optimal time-point of six hours after the exercise, serum uric acid, creatine kinase (CK) and lactate dehydrogenase (LDH) were determined by standard methods and HSP70 by the Western blot analysis. HSP70 responds differently to different types of running. For kidney, heart, soleus and gastrocnemius, the HSP70 expression increased, 230, 180, 150 and 120% respectively of the reference (horizontal). When the contraction was concentric (uphill) and compared to downhill the increase in response of HSP70 was greater in 80% for kidney, 75% for gastrocnemius, 60% for soleus and 280% for the heart. Uric acid was about 50% higher (0.64 ± 0.03 mg·dL−1) in the uphill group as compared to the horizontal or downhill groups. Similarly, the activities of serum CK and LDH were both 100% greater for both the uphill and downhill groups as compared to the horizontal group (2383 ± 253 and 647.00 ± 73 U/L, respectively). The responsiveness of HSP70 appeared to be quite different depending on the type of tissue, suggesting that the impact of exercise was not restricted to the muscles, but extended to the kidney tissue. The uphill exercise increases HSP70 beyond the eccentric type and the horizontal running was a lower HSP70 responsive stimulus.
Key Points
- Exercise can induce increases in HSP70 in the lung, kidney and heart, and in the soleus and gastrocnemius muscles, probably due to systemic alterations such as hypoxia, increase in temperature and the production of free radicals.
- Predominantly concentric contractions (running uphill), seem to be the most efficient way of increasing the HSP70 concentrations in the different tissues, followed by eccentric contraction (downhill) and lastly the concentric-eccentric cycle (horizontal).
- The energy demand, already known to influence HSP70, appears not to be the only factor responsible for the response of these proteins, considering that for the kidney and the soleus muscle, downhill running was more efficient in raising the HSP70 response than horizontal running.
- Future research should explore the mechanisms by which the eccentric, concentric and eccentric-concentric contractions are capable of influencing the responses of the heat shock proteins, opening possibilities for increasing the levels of these proteins in desirable situations, such as to protect against excess free radicals or injuries.
62.
Alana Pimentel Moura Mateus Grings Belisa dos Santos Parmeggiani Gustavo Flora Marcowich Anelise Miotti Tonin Carolina Maso Viegas Ângela Zanatta César Augusto João Ribeiro Moacir Wajner Guilhian Leipnitz 《Neurotoxicity research》2013,24(4):502-511
High tissue levels of glycine (GLY) are the biochemical hallmark of nonketotic hyperglycinemia (NKH), an inherited metabolic disease clinically characterized by severe neurological symptoms and brain abnormalities. Considering that the mechanisms underlying the neuropathology of this disease are not fully established, the present work investigated the in vivo effects of intracerebroventricular administration of GLY on important parameters of energy metabolism in cerebral cortex and striatum from young rats. Our results show that GLY reduced CO2 production using glucose as substrate and inhibited the activities of citrate synthase and isocitrate dehydrogenase in striatum, whereas no alterations of these parameters were verified in cerebral cortex 30 min after GLY injection. We also observed that GLY diminished the activities of complex IV in cerebral cortex and complex I–III in striatum at 30 min and inhibited complex I–III activity in striatum at 24 h after its injection. Furthermore, GLY reduced the activity of total and mitochondrial creatine kinase in both brain structures 30 min and 24 h after its administration. In contrast, the activity of Na+, K+-ATPase was not altered by GLY. Finally, the antioxidants N-acetylcysteine and creatine, and the NMDA receptor antagonist MK-801 attenuated or fully prevented the inhibitory effects of GLY on creatine kinase and respiratory complexes in cerebral cortex and striatum. Our data indicate that crucial pathways for energy production and intracellular energy transfer are severely compromised by GLY. It is proposed that bioenergetic impairment induced by GLY in vivo may contribute to the neurological dysfunction found in patients affected by NKH. 相似文献
63.
64.
Ricardo Augusto Barbieri Alessandro Moura Zagatto Fabio Milioni Fabio Augusto Barbieri 《Sport Sciences for Health》2016,12(2):247-253
Purpose
This study investigated the effects of 12-week of specific futsal training on body composition, oxygen uptake (VO2max), anaerobic capacity, and agility of male semi-professional futsal players.Methods
Thirteen athletes were subjected to a 12-week program of specific training for futsal with the external load of sessions prescribed from rated perceived exertion. VO2max, agility, anaerobic index, and body composition were assessed before and after the 12-week training program.Results
The main findings were that the 12-week training period was able to significantly reduce the fat percentage of body composition (?7.5 %) and to improve the agility (3.9 %), aerobic capacity (>7 %), and anaerobic index (6–25 %).Conclusions
Based on these results, it can be concluded that a 12-week program of specific training for futsal with the external load of sessions prescribed from rated perceived exertion can significantly improve the body composition, agility and aerobic and anaerobic capacity of semi-professional futsal players.65.
Carlos Eduardo Bezerra Moura Naisandra Bezerra Silva Juliana Carvalho Sa Geraldo Barroso Cavalcanti Junior Silvia Regina Batistuzzo de Medeiros Hugo Alexandre Oliveira Rocha Paula Carvalho Papa Clodomiro Alves Jr 《Artificial organs》2016,40(5):497-504
To evaluate the effect of topography in nanoscale, titanium surfaces were bombarded by argon ions (a chemically inert gas), in an atmosphere of plasma. The effects of surface parameters on morphology, adhesion, proliferation, and MC3T3‐E1 preosteoblasts differentiation were analyzed. Nontreated (smooth) surfaces were used as a control. The levels of average roughness (Ra) observed in bombarded and smooth titanium surfaces were of 95 and 14 nm, respectively. The wettability increased on treated surfaces. The number of attached cells (30 and 60 min) was significantly higher on the bombarded surface. The cell proliferation after 3 and 7 days was also significantly higher on the ion‐bombarded surface. In addition, the ALP activity and expression of osteocalcin were higher in cells grown on the treated surface. The results showed that bombardment with argon ions increased the roughness and the wettability of the Ti surface, promoting a significant increase in the adhesion, proliferation, and differentiation of preosteoblasts. 相似文献
66.
Ageing and Toll-like receptor expression by innate immune cells in chronic human schistosomiasis 下载免费PDF全文
Comin F Speziali E Martins-Filho OA Caldas IR Moura V Gazzinelli A Correa-Oliveira R Faria AM 《Clinical and experimental immunology》2007,149(2):274-284
There has been no systematic study of the immune response of individuals aged over 60 years living in Schistosomiasis mansoni-endemic areas, although senescence is reportedly associated with susceptibility to infection and progressive decline in immune function. We have shown previously, in two endemic areas in Minas Gerais, Brazil, that the frequency of individuals aged over 60 years with chronic schistosomiasis is no longer negligible. Moreover, several elderly individuals who have always lived in these endemic areas stay protected from infection. An important question for studies of ageing and disease control in developing countries is which differences in the immunological profile of these negatively tested (non-infected) individuals can account for their resistance to either infection or reinfection. We show, in the present study, that non-infected (negative) elderly individuals develop innate immune mechanisms of protection that replace the age-associated decline in T cell function. Non-infected elderly individuals from endemic areas of schistosome infection present an increase in the frequency of the natural killer (NK) CD56(low) subset of NK cells expressing Toll-like receptors (TLR)-1, -2, -3 and -4 as determined by flow cytometry analysis. In addition, the proportion of dendritic cells expressing TLR-1 is elevated as well as the frequency of monocytes expressing TLR-1 and -4. These results suggest that TLR expression by cells of the innate immune system may be related to the negative status of infection in some elderly individuals who are constantly exposed to S. mansoni. Developing mechanisms of protection from infection may represent a biomarker for healthy ageing in this population. 相似文献
67.
Kanamaru Y Arcos-Fajardo M Moura IC Tsuge T Cohen H Essig M Vrtovsnik F Loirat C Peuchmaur M Beaudoin L Launay P Lehuen A Blank U Monteiro RC 《European journal of immunology》2007,37(4):1116-1128
Myeloid cells bear Fc receptors (FcR) that mediate inflammatory signaling through the ITAM-containing FcRgamma adaptor. They express FcRgamma-associated FcalphaRI, which modulate either activating or inhibitory signaling depending on the type of ligand interaction. The role of FcalphaRIgamma in disease progression remains unknown, notably in IgA nephropathy (IgAN), one of major causes of end-stage renal disease, in which large amounts of circulating IgA-immune complexes (IC) may mediate receptor activation. To analyze the involvement of FcalphaRI activation in glomerulonephritis (GN), we generated Tg mice expressing a mutated, signaling-incompetent, human FcalphaRI(R209L) that cannot associate with FcRgamma. Like FcalphaRI(wt)-Tg mice, they developed mesangial IgA deposits but not macrophage infiltration. FcalphaRI activation in FcalphaRI(wt), but not in FcalphaRI(R209L), Tg mice resulted in marked inflammation with severe proteinuria and leukocyte infiltration in spontaneous IgAN or anti-glomerular basement membrane Ab-induced GN models. Receptor triggering of syngenically transferred FcalphaRI(wt) Tg macrophages into non-Tg animals induced their recruitment into injured kidneys during GN development. FcalphaRI(wt) cross-linking on macrophages activated MAP kinases and production of TNF-alpha and MCP-1. Moreover, IgA-IC from IgAN patients activated FcalphaRI and induced TNF-alpha production. Thus, FcalphaRI activation mediates GN progression by initiating a cytokine/chemokine cascade that promotes leukocyte recruitment and kidney damage. 相似文献
68.
Ramon Oliveira Souza Tadeu Henrique de Lima Rodrigo Lambert Oréfice Marcelo Gonzaga de Freitas Araújo Sandra Aparecida de Lima Moura Juliana Teixeira Magalhães Gisele Rodrigues da Silva 《Journal of pharmaceutical sciences》2018,107(10):2674-2685
Vulvovaginal candidiasis is an inflammation localized in the vulvovaginal area. It is mostly caused by Candida albicans. Its treatment is based on the systemic and local administration of antifungal drugs. However, this conventional therapy can fail owing to the resistance of the Candida species and noncompliance of patients. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers are single-use, antifungal, controlled drug delivery systems, and represent an alternative therapeutic scheme for the local treatment of vulvovaginal candidiasis. Nanofibers were characterized by analytical techniques and with an in vitro drug delivery study. In vitro and in vivo fungicidal activity of amphotericin B released from nanofibers was evaluated using the agar diffusion method and an experimental murine model of vulvovaginal candidiasis, respectively. Analytical techniques showed that amphotericin B was physically mixed in the polymeric nanofibers. Nanofibers controlled the delivery of therapeutic doses of amphotericin B for 8 consecutive days, providing effective in vitro antifungal activity and eliminated the in vivo vaginal fungal burden after 3 days of treatment and with only one local application. Amphotericin B-loaded poly(lactic-co-glycolic acid) nanofibers could be potentially applied as an alternative strategy for the local treatment of vulvovaginal candidiasis without inducing fungal resistance, yet ensuring patient compliance. 相似文献
69.
Felippe Lazar-Neto Andressa C. Sposato Louzada Ricardo Faé de Moura Fernando Morelli Calixto Marcia C. Castro 《Journal of immigrant and minority health / Center for Minority Public Health》2018,20(4):832-840
The goal of this paper is to assess the frequency of depression symptoms among Brazilian immigrants living in Massachusetts, the second largest Brazilian immigrant population in the United States, and to identify correlates of depression. A convenience sample of Brazilian immigrants aged 18 or older residing in Massachusetts was used. Data were collected from December 2013 to March 2014, in the Consulate General of Brazil in Boston and in three religious events, using a structure questionnaire and the Center for Epidemiological Studies Depression Scale (CES-D). Depression symptoms were observed in 35.3% of the respondents, with equal distribution by sex. Correlates of depression were low income, being single, poor English proficiency, and poor self-perception of health. These results suggest a need for community outreach, sensitization, and counseling, in Portuguese and adapted to the culture of Brazilian immigrants. 相似文献
70.
Arcuri EA de Araújo TL Veiga EV de Oliveira SM Lamas JL Santos JL 《Revista da Escola de Enfermagem da U S P》2007,41(1):147-153
This article pays homage to Sergei Nicolai Korotkoff, for the centenary of the auscultatory method discovery. It refers to his discover of blood pressure auscultatory method in Russia, in 1905; presents the evidence that resulted in the development of sphygmomanometry studies in Brasil; describes the important contribution of the Nursing School of the University of S?o Paulo to the development of blood pressure measurement research; and analyses the results of the research field of "Cuff width influence in blood pressure measurement", created at the Nursing School of The University of S?o Paulo, in 1974. The scientific results of doctoral studies are presented, identifying the research groups that are contributing to defying knowledge in this area. The article demonstrates the consolidation of the results related to the initial doctoral program studies developed in the area. Confirmation of hypothesis in longitudinal studies is emphasized. 相似文献