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排序方式: 共有3999条查询结果,搜索用时 15 毫秒
41.
Eugen Frišman Oliver Rácz Anna Chmelárová 《Burns : journal of the International Society for Burn Injuries》2013
Red cell superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were measured in 66 burned patients (57 men, 9 women, age 16–78 years). BSAB varied from 15 to 93% and ABSI from 3 to 14 points. In the first week after injury the activity of SOD was significantly decreased as compared with the activity of the enzymes in the control group and was also below the reference values. Later the activity of SOD increased up to the normal range. The activity of CAT followed a similar pattern but the differences were not significant. No significant changes in red cell GPX were found during the monitored period. We did not find any significant association between the antioxidant enzyme activities and the markers of burns severity. On the other side there was a significant indirect association between the change of SOD activity (calculated as a difference between the first week values after the injury and the activities measured later) and BSAB. 相似文献
42.
Investigating the human immunodeficiency virus type 1-infected monocyte-derived macrophage secretome
Ciborowski P Kadiu I Rozek W Smith L Bernhardt K Fladseth M Ricardo-Dukelow M Gendelman HE 《Virology》2007,363(1):198-209
Mononuclear phagocytes (bone marrow monocyte-derived macrophages, alveolar macrophages, perivascular macrophages, and microglia) are reservoirs and vehicles of dissemination for the human immunodeficiency virus type-1 (HIV-1). How virus alters mononuclear phagocyte immunoregulatory activities to complete its life cycle and influence disease is incompletely understood. In attempts to better understanding the influence of virus on macrophage functions, we used one-dimensional electrophoresis, and liquid chromatography tandem mass spectrometry to analyze the secretome of HIV-1-infected human monocyte-derived macrophages. We identified 110 proteins in culture supernatants of control (uninfected) and virus-infected cells. Differentially expressed cytoskeletal, enzymes, redox, and immunoregulatory protein classes were discovered and validated by Western blot tests. These included, but were not limited to, cystatin C, cystatin B, chitinase 3-like 1 protein, cofilin-1, l-plastin, superoxide dismutase, leukotriene A(4) hydrolase, and alpha-enolase. This study, using a unique proteomics platform, provides novel insights into virus-host cell interactions that likely affect the functional role of macrophages in HIV disease. 相似文献
43.
In this study, chitosan-assembled zinc oxide nanoparticle (CZNP) was successfully prepared for evaluated for its anticancer efficacy against cervical cancer cells. The CZNP particles were nanosized and spherical in shape. The zinc oxide nanoparticle (ZNP) and CZNP showed significant cytotoxicity in cervical cancer cells in a concentration-dependent manner. Results showed that the enhanced cytotoxicity was mainly attributed to the reactive oxygen species (ROS) generation in the cancer cells. The apoptosis assay further revealed that apoptosis was the main reason behind the cell killing effect of the zinc oxide nanoparticles. The apoptosis was further confirmed by the nuclear chromatin assay. Live dead assay showed increased red fluorescent cell for CZNP treated cancer cells. Overall, metal oxide present in nanoparticulate dimensions will be advantageous in imparting the cytotoxicity to cervical cancer cell. 相似文献
44.
Valerii E. Orel Marina Tselepi Thanos Mitrelias Alexander Rykhalskyi Andriy Romanov Valerii B. Orel Anatoliy Shevchenko Anatoliy Burlaka Sergey Lukin Crispin H.W. Barnes 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(4):1249-1256
Modulation of reactive oxygen and nitrogen species in a tumor could be exploited for nanotherapeutic benefits. We investigate the antitumor effect in Walker-256 carcinosarcoma of magnetic nanodots composed of doxorubicin-loaded Fe3O4 nanoparticles combined with electromagnetic fields. Treatment using the magnetic nanodot with the largest hysteresis loop area (3402 erg/g) had the greatest antitumor effect with the minimum growth factor 0.49 ± 0.02 day–1 (compared to 0.58 ± 0.02 day–1 for conventional doxorubicin). Electron spin resonance spectra of Walker-256 carcinosarcoma treated with the nanodots, indicate an increase of 2.7 times of free iron (that promotes the formation of highly reactive oxygen species), using the nanodot with the largest hysteresis loop area, compared to conventional doxorubicin treatment as well as increases in ubisemiquinone, lactoferrin, NO-FeS-proteins. Hence, we provide evidence that the designed magnetic nanodots can modulate the tumor redox state. We discuss the implications of these results for cancer nanotherapy. 相似文献
45.
Fawad Ur Rehman Tianyu Du Sana Shaikh Xuerui Jiang Yun Chen Xiaoqi Li Huan Yi Jiang Hui Baoan Chen Matthias Selke Xuemei Wang 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(8):2619-2631
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al. 相似文献
46.
47.
Context: Previous in vitro studies have demonstrated that emodin (1,3,8-trihydroxy-6-methyl-anthraquinone), an anthraquinone derivative from the rhizome of Rheum palmatum L., can inhibit the activation of P2X7 receptors (P2X7R) as a potential antagonist. However, the effects of emodin on P2X7R-related inflammatory processes remain unclear.Objective: This study aimed to investigate the effects of emodin on different inflammation responses of macrophages induced by ATP, the natural ligand of P2X7R.Materials and methods: Rat peritoneal macrophages were treated with millimolar ATP and emodin (0.1, 0.3,?1,?3,?10?µM) or brilliant blue G (BBG, 0.1,?1,?10?µM). Cytosolic Ca2+ concentration ([Ca2+]c) was detected by fluorescent Ca2+ imaging. Interleukin-1β (IL-1β) release was measured by rat IL-1β ELISA kits. Reactive oxygen species (ROS) generation was examined by dihydroethidium (DHE) fluorescent staining. Phagocytic activity was tested by neutral red uptake assay.Results: We found that the [Ca2+]c increase evoked by ATP (5?mM) was inhibited by emodin, in a dose-dependent manner with IC50 of 0.5?μM. Furthermore, emodin reduced the IL-1β release induced by ATP (2?mM) in lipopolysaccharide (LPS)-activated macrophages, with an IC50 of 1.6?μM. Emodin also strongly suppressed the ROS production and phagocytosis attenuation triggered by ATP (1?mM), with IC50 values of 1?μM and 0.7?μM, respectively. Besides, BBG, a specific antagonist of P2X7R, exhibited similar suppressive effects on these inflammation responses.Conclusion: These results showed the inhibitory effects of emodin on ATP-induced [Ca2+]c increase, IL-1β release, ROS production and phagocytosis attenuation in rat peritoneal macrophages, by inhibiting the activation of P2X7R. 相似文献
48.
Objective
Benzene, as a volatile organic compound, is known as one of the main air pollutants in the environment. The aim of this review is to summarize all available evidences on non-cancerous health effects of benzene providing an overview of possible association of exposure to benzene with human chronic diseases, specially, in those regions of the world where benzene concentration is being poorly monitored.Methodology
A bibliographic search of scientific databases including PubMed, Google Scholar, and Scirus was conducted with key words of “benzene toxic health effects”, “environmental volatile organic compounds”, “diabetes mellitus and environmental pollutants”, “breast cancer and environmental pollution”, “prevalence of lung cancer”, and “diabetes prevalence”. More than 300 peer reviewed papers were examined. Experimental and epidemiologic studies reporting health effects of benzene and volatile organic compounds were included in the study.Results
Epidemiologic and experimental studies suggest that benzene exposure can lead to numerous non-cancerous health effects associated with functional aberration of vital systems in the body like reproductive, immune, nervous, endocrine, cardiovascular, and respiratory.Conclusion
Chronic diseases have become a health burden of global dimension with special emphasis in regions with poor monitoring over contents of benzene in petrochemicals. Benzene is a well known carcinogen of blood and its components, but the concern of benzene exposure is more than carcinogenicity of blood components and should be evaluated in both epidemiologic and experimental studies. Aspect of interactions and mechanism of toxicity in relation to human general health problems especially endocrine disturbances with particular reference to diabetes, breast and lung cancers should be followed up. 相似文献49.
Kaijun Liu Guowei Zhang Zhi Wang Yong Liu Jianyun Dong Xiaomei Dong Jinyi Liu Jia Cao Lin Ao Shaoxiang Zhang 《Toxicology letters》2014
The increasing exposure to radiofrequency (RF) radiation emitted from mobile phone use has raised public concern regarding the biological effects of RF exposure on the male reproductive system. Autophagy contributes to maintaining intracellular homeostasis under environmental stress. To clarify whether RF exposure could induce autophagy in the spermatocyte, mouse spermatocyte-derived cells (GC-2) were exposed to 1800 MHz Global System for Mobile Communication (GSM) signals in GSM-Talk mode at specific absorption rate (SAR) values of 1 w/kg, 2 w/kg or 4 w/kg for 24 h, respectively. The results indicated that the expression of LC3-II increased in a dose- and time-dependent manner with RF exposure, and showed a significant change at the SAR value of 4 w/kg. The autophagosome formation and the occurrence of autophagy were further confirmed by GFP-LC3 transient transfection assay and transmission electron microscopy (TEM) analysis. Furthermore, the conversion of LC3-I to LC3-II was enhanced by co-treatment with Chloroquine (CQ), indicating autophagic flux could be enhanced by RF exposure. Intracellular ROS levels significantly increased in a dose- and time-dependent manner after cells were exposed to RF. Pretreatment with anti-oxidative NAC obviously decreased the conversion of LC3-I to LC3-II and attenuated the degradation of p62 induced by RF exposure. Meanwhile, phosphorylated extracellular-signal-regulated kinase (ERK) significantly increased after RF exposure at the SAR value of 2 w/kg and 4 w/kg. Moreover, we observed that RF exposure did not increase the percentage of apoptotic cells, but inhibition of autophagy could increase the percentage of apoptotic cells. These findings suggested that autophagy flux could be enhanced by 1800 MHz GSM exposure (4 w/kg), which is mediated by ROS generation. Autophagy may play an important role in preventing cells from apoptotic cell death under RF exposure stress. 相似文献
50.
Nengwen Xia Hui Wang Xueliang Liu Qi Shao Da Ao Yulin Xu Sen Jiang Jia Luo Jiajia Zhang Nanhua Chen Franois Meurens Wanglong Zheng Jianzhong Zhu 《Viruses》2021,13(1)
African swine fever virus (ASFV) is a highly pathogenic large DNA virus that causes African swine fever (ASF) in domestic pigs and wild boars. The p17 protein, encoded by the D117L gene, is a major transmembrane protein of the capsid and the inner lipid envelope. The aim of this study was to investigate the effects of p17 on cell proliferation and the underlying mechanisms of action. The effects of p17 on cell proliferation, cell cycle, apoptosis, oxidative stress, and endoplasmic reticulum (ER) stress have been examined in 293T, PK15, and PAM cells, respectively. The results showed that p17 reduced cell proliferation by causing cell cycle arrest at G2/M phase. Further, p17-induced oxidative stress and increased the level of intracellular reactive oxygen species (ROS). Decreasing the level of ROS partially reversed the cell cycle arrest and prevented the decrease of cell proliferation induced by p17 protein. In addition, p17-induced ER stress, and alleviating ER stress decreased the production of ROS and prevented the decrease of cell proliferation induced by p17. Taken together, this study suggests that p17 can inhibit cell proliferation through ER stress and ROS-mediated cell cycle arrest, which might implicate the involvement of p17 in ASF pathogenesis. 相似文献