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991.
Gene expression of visna virus is highly restricted in monocytes, but is induced when monocytes differentiate into macrophages. A previous study on differential regulation of visna virus gene expression revealed that a specific AP-1 site in the long terminal repeat of the viral DNA is required for phorbol-ester-induced gene expression in macrophages (Gabuzda, Hess, Small, and Clements, Mol. Cell. Biol., 9, 2728-2733). In the present investigation, we examined the association of two DNA binding proteins, the proto-oncogene proteins FOS and JUN, with this AP-1 site in the visna virus LTR. We demonstrated that the concentrations of these two proteins and their mRNAs increased in U937 cells after phorbol ester induction. Furthermore, the binding of cellular proteins from the U937 nuclear extracts to this AP-1 site was significantly decreased in the presence of antibodies to JUN and FOS. In vitro-translated JUN protein also binds to this AP-1 sequence, and this binding is enhanced by the FOS protein. These results indicate that JUN and FOS are directly involved in the differential regulation of visna virus gene expression. 相似文献
992.
993.
Ntziachristos V Turner G Dunham J Windsor S Soubret A Ripoll J Shih HA 《Journal of biomedical optics》2005,10(6):064007
Fluorescence imaging of tissues has gained significant attention in recent years due to the emergence of appropriate reporter technologies that enable noninvasive sensing of molecular function in vivo. Two major approaches have been used so far for fluorescence molecular imaging, i.e., epi-illumination (reflectance) imaging and fluorescence molecular tomography. Transillumination is an alternative approach that has been employed for imaging tissues in the past and could be similarly beneficial for fluorescence molecular imaging. We investigate data normalization schemes in reflectance and transillumination mode and experimentally demonstrate that normalized transillumination offers significant advantages over planar reflectance imaging and over nonnormalized methods. Our observations, based on phantoms and on postmortem and in vivo mouse measurements display image quality improvement, superior depth sensitivity, and improved imaging accuracy over the nonnormalized methods examined. Normalized planar imaging retains implementation simplicity and could be used to improve on standard fluorescence reflectance imaging and as a simplified alternative to the more integrated and accurate tomographic methods. 相似文献
994.
Chih-Chien Hu Szu-Yuan Chen Chun-Chieh Chen Yu-Han Chang Steve Wen-Neng Ueng Hsin-Nung Shih 《The Journal of arthroplasty》2017,32(6):1940-1945
Background
Total knee arthroplasty in the presence of a huge bone and soft-tissue defect is always a challenge. A rotating-hinged (RH) megaprosthesis is indicated for extensive soft-tissue loss with a huge bone defect such as a primary or metastatic neoplasm of the bone, repeat periprosthetic joint infection, or extensive trauma of the knee. However, the reported survivorship of RH megaprostheses is unsatisfactory. The aim of this study was to evaluate the survivorship of megaprostheses and the factors that contribute to implant survival.Methods
A total of 103 RH knee megaprostheses were implanted in 85 patients between January 2001 and June 2013. Each prosthesis was a modular custom-made (CM) cemented or cementless fixed total knee system (United USTAR system). Clinical results and prosthesis survivorship were evaluated between the 2 groups.Results
The overall survivorship of this CM knee megaprosthesis was 91% at 2 years, 83% at 5 years, and 68% at 10 years. The cumulative component survivorship was 87% in the cemented group and 96% in the cementless group at 2 years compared with 75% in the cemented group and 94% in the cementless group at 5 years. The failure mechanism included loosening in 5 and breakage in 6 patients in the cemented stem group. The survivorship of the cementless fixed component was significantly superior to that of the cemented fixed component.Conclusion
Our data suggest that modular RHCM knee megaprosthesis provides an acceptable clinical result. A diaphyseal long stem with cementless fixation was more reliable and durable than its cemented counterpart. 相似文献995.
Hsiu‐Ju Yen Shih‐Hsiang Chen Tsung‐Yen Chang Chao‐Ping Yang Dong‐Tsamn Lin Iou‐Jih Hung Kai‐Hsin Lin Jiann‐Shiuh Chen Chih‐Cheng Hsiao Tai‐Tsung Chang Te‐Kao Chang Ching‐Tien Peng Ming‐Tsan Lin Tang‐Her Jaing Hsi‐Che Liu Shiann‐Tarng Jou Meng‐Yao Lu Chao‐Neng Cheng Jiunn‐Ming Sheen Shyh‐Shin Chiou Giun‐Yi Hung Kang‐Hsi Wu Ting‐Chi Yeh Shih‐Chung Wang Rong‐Long Chen Hsiu‐Hao Chang Yung‐Li Yang Shu‐Huey Chen Shin‐Nan Cheng Yu‐Hsiang Chang Bow‐Wen Chen Yuh‐Lin Hsieh Fang‐Liang Huang Wan‐Ling Ho Jinn‐Li Wang Chia‐Yau Chang Yu‐Hua Chao Pei‐Chin Lin Yu‐Chieh Chen Yu‐Mei Liao Tung‐Huei Lin Lee‐Yung Shih Der‐Cherng Liang 《Pediatric blood & cancer》2017,64(10)
996.
Rubus idaeus extract suppresses migration and invasion of human oral cancer by inhibiting MMP‐2 through modulation of the Erk1/2 signaling pathway
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Yih‐Shou Hsieh Pei‐Ni Chen Shun‐Fa Yang Shih‐Hsuan‐Lin Yang‐Yu Chen Chiao‐Wen Lin Yu‐Chao Chang 《Environmental toxicology》2017,32(3):1037-1046
Raspberries (Rubus idaeus L.) have been extensively studies worldwide because of their beneficial effects on health. Recently reports indicate that crude extracts of Rubus idaeus (RIE) have antioxidant and anticancer ability. The aim of this study was to evaluate the mechanism of its antimetastatic ability in oral cancer cells. In this study, SCC‐9 and SAS oral cancer cells were subjected to a treatment with RIE and then analyzed the effect of RIE on migration and invasion. The addition of RIE inhibited the migration and invasion ability of oral cancer cells. Real time PCR, western blot and zymography analysis demonstrated that mRNA, protein expression and enzyme activity of matrix metalloproteinases‐2 (MMP‐2) were down‐regulated by RIE. Moreover, the phosphorylation of Focal adhesion kinase (FAK), src, and extracellular signal‐regulated kinase (ERK) were inhibited after RIE treatment. In conclusion, these results demonstrated that RIE exerted an inhibitory effect of migration and invasion in oral cancer cells and alter metastasis by suppression of MMP‐2 expression through FAK/Scr/ERK signaling pathway. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1037–1046, 2017. 相似文献
997.
Juan‐Cheng Yang Guan‐Yu Chen Chi‐Chen Fan Yu‐Chuan Chien Pei‐Shan Lin Shih‐Chun Candice Lung Wei‐Chao Chang 《Environmental toxicology》2017,32(11):2379-2391
Burning incense to worship deities is a popular religious ritual in large parts of Asia, and is a popular custom affecting more than 1.5 billion adherents. Due to incomplete combustion, burning incense has been well recognized to generate airborne hazards to human health. However, the correlation between burning incense and lung cancer in epidemiological studies remains controversy. Therefore, we speculated that some unknown materials in incense smoke are involved in the initiation or progression of lung cancer. Based on this hypothesis, we identified a major compound auramine O (AuO) from the water‐soluble fraction of incense burned condensate using mass spectrometry. AuO is commonly used in incense manufacture as a colorant. Due to thermostable, AuO released from burned incenses becomes an unexpected air pollutant. AuO is classified as a Group 2B chemical by the International Agency of Research on Cancer (IARC), however, the damage of AuO to the respiratory system remains elusive. Our study revealed that AuO has no apparent effect on malignant transformation; but, it dramatically promotes lung cancer malignancy. AuO accumulates in the nucleus and induces the autophagy activity in lung tumor cells. AuO significantly enhances migration and invasive abilities and the in vitro and in vivo stemness features of lung tumor cells through activating the expression of aldehyde dehydrogenase family 1 member A1 (ALDH1A1), and ALDH1A1 knockdown attenuates AuO‐induced autophagy activity and blocks AuO‐induced lung tumor malignancy. In conclusion, we found that AuO, an ingredient of incense smoke, significantly increases the metastatic abilities and stemness characters of lung tumor cells through the activation of ALDH1A1, which is known to be associated with poor outcome and progression of lung cancer. For public health, reducing or avoiding the use of AuO in incense is recommended. 相似文献
998.
Taiwanin E inhibits cell migration in human LoVo colon cancer cells by suppressing MMP‐2/9 expression via p38 MAPK pathway
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Hsi‐Hsien Hsu Wei‐Wen Kuo Cecilia Hsuan Day Marthandam Asokan Shibu Shin‐Yi Li Sheng‐Huang Chang Hui‐Nung Shih Ray‐Jade Chen Vijaya Padma Viswanadha Chih‐Yang Huang 《Environmental toxicology》2017,32(8):2021-2031
Taiwanin E is a natural compound which is structurally analogous to estrogen II and is abundantly found in Taiwania cryptomerioides. It has been previously reported for its anticancer effects; however, the pharmaceutical effect of Taiwanin E on Human LoVo colon cancer cells is not clear. In this study, we investigated the effects of Taiwanin E on metastasis and the associated mechanism of action on Human LoVo colon cancer cells with respect to the modulations in their cell migration and signaling pathways associated with migration. The results showed that Taiwanin E inhibited cell migration ability correlated with reduced expression and activity of MMP‐2 and MMP‐9. In addition, Taiwanin E induced activation of p38 through phosphorylation. Inhibition of p38α/β significantly abolished the effect of Taiwanin E on cell migration and MMP‐2/‐9 activity. Our results conclude that Taiwanin E inhibited cell migration chiefly via p38α MAPK pathway and in a lesser extend via p38β MAPK. The results elucidate the potential of the phytoestrogen natural compound Taiwanin E as a cancer therapeutic agent in inhibiting the cell migration. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 2021–2031, 2017. 相似文献
999.
1000.