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981.
Wadden TA Neiberg RH Wing RR Clark JM Delahanty LM Hill JO Krakoff J Otto A Ryan DH Vitolins MZ;Look AHEAD Research Group 《Obesity (Silver Spring, Md.)》2011,19(10):1987-1998
This report provides a further analysis of the year 4 weight losses in the Look AHEAD (Action for Health in Diabetes) study and identifies factors associated with long-term success. A total of 5,145 overweight/obese men and women with type 2 diabetes were randomly assigned to an intensive lifestyle intervention (ILI) or a usual care group, referred to as Diabetes Support and Education (DSE). ILI participants were provided approximately weekly group or individual treatment in year 1; continued but less frequent contact was provided in years 2-4. DSE participants received three group educational sessions in all years. As reported previously, at year 4, ILI participants lost an average of 4.7% of initial weight, compared with 1.1% for DSE (P < 0.0001). More ILI than DSE participants lost ≥ 5% (46% vs. 25%, P < 0.0001) and ≥ 10% (23% vs. 10%, P < 0.0001) of initial weight. Within the ILI, achievement of both the 5% and 10% categorical weight losses at year 4 was strongly related to meeting these goals at year 1. A total of 887 participants in ILI lost ≥ 10% at year 1, of whom 374 (42.2%) achieved this loss at year 4. Participants who maintained the loss, compared with those who did not, attended more treatment sessions and reported more favorable physical activity and food intake at year 4. These results provide critical evidence that a comprehensive lifestyle intervention can induce clinically significant weight loss (i.e., ≥ 5%) in overweight/obese participants with type 2 diabetes and maintain this loss in more than 45% of patients at 4 years. 相似文献
982.
Benedetti G Morais KL Guerreiro JR de Oliveira EF Hoshida MS Oliveira L Sass N Lebrun I Ulrich H Lameu C de Camargo AC 《PloS one》2011,6(8):e23680
Preeclampsia, a pregnancy-specific syndrome characterized by hypertension, proteinuria and edema, is a major cause of fetal and maternal morbidity and mortality especially in developing countries. Bj-PRO-10c, a proline-rich peptide isolated from Bothrops jararaca venom, has been attributed with potent anti-hypertensive effects. Recently, we have shown that Bj-PRO-10c-induced anti-hypertensive actions involved NO production in spontaneous hypertensive rats. Using in vitro studies we now show that Bj-PRO-10c was able to increase NO production in human umbilical vein endothelial cells from hypertensive pregnant women (HUVEC-PE) to levels observed in HUVEC of normotensive women. Moreover, in the presence of the peptide, eNOS expression as well as argininosuccinate synthase activity, the key rate-limiting enzyme of the citrulline-NO cycle, were enhanced. In addition, excessive superoxide production due to NO deficiency, one of the major deleterious effects of the disease, was inhibited by Bj-PRO-10c. Bj-PRO-10c induced intracellular calcium fluxes in both, HUVEC-PE and HUVEC, which, however, led to activation of eNOS expression only in HUVEC-PE. Since Bj-PRO-10c promoted biological effects in HUVEC from patients suffering from the disorder and not in normotensive pregnant women, we hypothesize that Bj-PRO-10c induces its anti-hypertensive effect in mothers with preeclampsia. Such properties may initiate the development of novel therapeutics for treating preeclampsia. 相似文献
983.
Caveolae-Dependent and -Independent Uptake of Albumin in Cultured Rodent Pulmonary Endothelial Cells
Hui-Hua Li Jin Li Karla J. Wasserloos Callen Wallace Mara G. Sullivan Philip M. Bauer Donna B. Stolz Janet S. Lee Simon C. Watkins Claudette M. St Croix Bruce R. Pitt Li-Ming Zhang 《PloS one》2013,8(11)
Although a critical role for caveolae-mediated albumin transcytosis in pulmonary endothelium is well established, considerably less is known about caveolae-independent pathways. In this current study, we confirmed that cultured rat pulmonary microvascular (RPMEC) and pulmonary artery (RPAEC) endothelium endocytosed Alexa488-labeled albumin in a saturable, temperature-sensitive mode and internalization resulted in co-localization by fluorescence microscopy with cholera B toxin and caveolin-1. Although siRNA to caveolin-1 (cav-1) in RPAEC significantly inhibited albumin uptake, a remnant portion of albumin uptake was cav-1-independent, suggesting alternative pathways for albumin uptake. Thus, we isolated and cultured mouse lung endothelial cells (MLEC) from wild type and cav-1-/- mice and noted that ~ 65% of albumin uptake, as determined by confocal imaging or live cell total internal reflectance fluorescence microscopy (TIRF), persisted in total absence of cav-1. Uptake of colloidal gold labeled albumin was evaluated by electron microscopy and demonstrated that albumin uptake in MLEC from cav-1-/- mice was through caveolae-independent pathway(s) including clathrin-coated pits that resulted in endosomal accumulation of albumin. Finally, we noted that albumin uptake in RPMEC was in part sensitive to pharmacological agents (amiloride [sodium transport inhibitor], Gö6976 [protein kinase C inhibitor], and cytochalasin D [inhibitor of actin polymerization]) consistent with a macropinocytosis-like process. The amiloride sensitivity accounting for macropinocytosis also exists in albumin uptake by both wild type and cav-1-/- MLEC. We conclude from these studies that in addition to the well described caveolar-dependent pulmonary endothelial cell endocytosis of albumin, a portion of overall uptake in pulmonary endothelial cells is cav-1 insensitive and appears to involve clathrin-mediated endocytosis and macropinocytosis-like process. 相似文献
984.
985.
Tree–grass coexistence is broadly observed in tropical savannas. Recent studies indicate that, in arid savannas, such coexistence is stable and related to water availability. The role of different factors (from niche separation to demographic structure) has been explored. Nevertheless, spatial mechanisms of water–vegetation interactions have been rarely taken into account, despite their well-known importance for vegetation distribution. Here, we introduce a spatial model including tree and grass biomass dynamics, together with soil and surface water dynamics. We consider two water–vegetation feedbacks. Grasses increase water infiltration into the soil, while tree shadow limits evaporation, and both mechanisms increase soil water availability, leading to positive feedbacks. The infiltration feedback can also lead to spatial pattern formation. Despite the fact that trees and grasses compete for the same resource, namely water, we observe stable coexistence as a possible model outcome. The system displays a complex behavior, with multiple stable states and possible catastrophic shifts between states, e.g., patterned grassland, bare soil and forest. In our model, coexistence is always linked with multi-stability and spatial pattern formation, driven by grass infiltration feedback. Given such complex model solutions, we expect that, under real conditions, heterogeneities and disturbances, acting on the multi-stable states, may further foster coexistence. 相似文献
986.
Buchbinder M 《Medical anthropology quarterly》2011,25(4):457-478
This article examines an explanation circulating within a U.S. multidisciplinary pediatric pain clinic that links the neurobiology of functional pain disorders to desirable personal attributes such as smartness and creativity. Drawing on ethnographic observations and the analysis of video-recorded clinical interactions and focusing on two cases, I introduce the term personhood diagnostics to explore how the explanatory framework worked not only to pinpoint a pathophysiological mechanism for pain to legitimize it as "real" but also to cast patients as virtuous persons. In doing so, it laid the groundwork for an ethic of clinical care that privileged the patient's responsibility for treatment. Within this narrative logic, diagnostic explanations reveal not only causal pathways but also predictive claims about recovery. By considering what is at stake when personal attributes are marshaled within a neurobiological diagnostic register that also lays out the patient's role in healing, this article complicates psychosomatic accounts of pain. 相似文献
987.
Maxwel?A.?Abegg Rodrigo?Lucietto Paulo?V.?G.?Alabarse Marcus?F.?A.?Mendes Mara?Silveira?BenfatoEmail author 《Mycopathologia》2011,171(1):35-41
Resistance to the toxic effects of reactive oxygen species produced by phagocytes and production of hydrolytic enzymes are
important aspects of Candida albicans virulence. In this report, we compared twelve C. albicans isolates for their in vitro capacity to resist oxidants—hydrogen peroxide, menadione and paraquat; and to produce hydrolytic
enzymes—phospholipase and protease. Different C. albicans isolates showed different degrees of resistance to oxidants as well as differences in production of hydrolytic enzymes. Resistance
to oxidative stress did not correlate with production of hydrolytic enzymes. This reinforces the view that C. albicans differentially regulates the expression of virulence factors in response to local environmental conditions. 相似文献
988.
Sporotrichosis is a subcutaneous mycosis caused by Sporothrix schenckii. Zoonotic transmission to man can occur after scratches or bites of animals, mainly cats. In this study, the gamma radiation
effects on yeast of S. schenckii were analyzed with a view of developing a radioattenuated vaccine for veterinary use. The cultures were irradiated at doses
ranging from 1.0 to 9.0 kGy. The reproductive capacity was measured by the ability of cells to form colonies. No colonies
could be recovered above 8.0 kGy, using inocula up to 107 cells. Nevertheless, yeast cells irradiated with 7.0 kGy already were unable to produce infection in immunosuppressed mice.
Evaluation by the FungaLight™ Kit (Invitrogen) indicated that yeast cells remained viable up to 9.0 kGy. At 7.0 kGy, protein
synthesis, estimated by the incorporation of [L-35S] methionine, continues at levels slightly lower than the controls, but a significant decrease was observed at 9.0 kGy. The
DNA of 7.0 kGy irradiated cells, analyzed by electrophoresis in agarose gel, was degraded. Cytoplasmic vacuolation was the
main change verified in these cells by transmission electron microscopy. The dose of 7.0 kGy was considered satisfactory for
yeast attenuation since irradiated cells were unable to produce infection but retained viability, metabolic activity, and
morphology. 相似文献
989.
990.
Ferreira AV Segatto M Menezes Z Macedo AM Gelape C de Oliveira Andrade L Nagajyothi F Scherer PE Teixeira MM Tanowitz HB 《Microbes and infection / Institut Pasteur》2011,13(12-13):1002-1005
Trypanosoma cruzi the cause of Chagas disease persists in tissues of infected experimental animals and humans. Here we demonstrate the persistence of the parasite in adipose tissue from of three of 10 elderly seropositive patients with chronic chagasic heart disease. Nine control patients had no parasites in the fat. We also demonstrate that T. cruzi parasitizes primary adipocytes in vitro. Thus, in humans as in mice the parasite may persist in adipose tissue for decades and become a reservoir of infection. 相似文献