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991.
Jin Zhang Meng Xie Mi Li Jinhua Ding Yunqiao Pu Anthony C. Bryan William Rottmann Kimberly A. Winkeler Cassandra M. Collins Vasanth Singan Erika A. Lindquist Sara S. Jawdy Lee E. Gunter Nancy L. Engle Xiaohan Yang Kerrie Barry Timothy J. Tschaplinski Jeremy Schmutz Gerald A. Tuskan Wellington Muchero Jin‐Gui Chen 《Plant biotechnology journal》2020,18(3):859-871
992.
Qiuyun Wu Lei Han Wenwen Gui Feng Wang Weiwen Yan Hua Jiang 《Journal of cellular and molecular medicine》2020,24(24):14339
Inhalation and deposition of crystalline silica particles in the lung can cause pulmonary fibrosis, then leading to silicosis. Given the paucity of effective drugs for silicosis, new insights for understanding the mechanisms of silicosis, including lung fibroblast activation and myofibroblast differentiation, are essential to explore therapeutic strategies. Our previous research showed that the up‐regulation of miR‐503 alleviated silica‐induced pulmonary fibrosis in mice. In this study, we investigated whether miR‐503 can regulate the TGF‐β1‐induced effects in lung fibroblasts. Mimic‐based strategies aiming at up‐regulating miR‐503 were used to discuss the function of miR‐503 in vivo and in vitro. We found that the expression level of miR‐503 was decreased in fibroblasts stimulated by TGF‐β1, and the up‐regulation of miR‐503 reduced the release of fibrotic factors and inhibited the migration and invasion abilities of fibroblasts. Combined with the up‐regulation of miR‐503 in a mouse model of silica‐induced pulmonary fibrosis, we revealed that miR‐503 mitigated the TGF‐β1‐induced effects in fibroblasts by regulating VEGFA and FGFR1 and then affecting the MAPK/ERK signalling pathway. In conclusion, miR‐503 exerted protective roles in silica‐induced pulmonary fibrosis and may represent a novel and potent candidate for therapeutic strategies in silicosis. 相似文献
993.
Marine Micromonospora was revealed to be a rather untapped and a rich source of chemically diverse and unique bioactive natural products. This review is aimed to make a comprehensive survey of secondary metabolites that were derived from marine Micromonospora including chemical diversity and biological activities. A total of 116 compounds from 41 marine Micromonospora species have been reported, covering the literatures from 1997 to 2019. These compounds contain several structural classes such as polyketides (PKS), nonribosomal peptides (NRPS), PKS‐NRPS hybrids, terpenes and others, and they present cytotoxic, antibacterial, antiparasitic, chemopreventive or antioxidant activities. 相似文献
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995.
996.
Yong‐Gang Hu Yi‐Hong Shen Ze Zhang Gui‐Qin Shi 《Archives of insect biochemistry and physiology》2013,83(1):41-55
The phenomenon that epidermal cells under the white stripes rather than black stripes contain many uric acid granules was found in larvae of several Lepidopteran species. However, the biological mechanism of this phenomenon is still unknown. In the present study, we take advantage of several silkworm (Bombyx mori) body color mutant strains to investigate the deposition patterns and biological mechanism of urate and melanin in the integuments of these mutant larvae. By imaging with transmission electron microscope, we found that there were some melanin granules in the larval cuticle in black body color mutant plain Black (pB), but not in background strain plain (p) with white larval body color. In contrast, the larval epidermal cell of background strain had much more urate granules than that of black one. Furthermore, the uric acid content under the black stripes was significantly lower than that under the white stripes in a single individual of mottled stripe (pS) with black and white stripes in each segment. Ultraviolet A (UVA) exposure experiments showed that the distinct oily (od) mutant individuals with translucent larval integument were more sensitive to the UVA damage than black body color mutant and background strain without any pigmentation in the larval cuticle. This is likely due to the absence of melanin granules and few urate granules in the integument of od mutant. Thus, both the deposited melanin granules in the cuticle and the abundant urate granules in the epidermis cells constitute effective barriers for the silkworm to resist UVA‐induced damage. 相似文献
997.
Bei‐Bei Deng Bao‐Ping Jiao Yang‐Jun Liu Yan‐Rong Li Gui‐Jun Wang 《Cell biology international》2020,44(9):1890-1899
Adjuvant chemotherapy in combination with surgery is expected to be a curative strategy for gastric cancer. However, drug resistance remains an obstacle in effective chemotherapy. Therefore, understanding the potential mechanisms of chemotherapy induced gastric cancer cell death is of great importance. We demonstrated that BIX‐01294 (BIX) at low concentration could induce autophagic flux by converting LC3B‐I to LC3B‐II and directly activate autophagy associated cell death in gastric cancer cell lines at high concentration. BIX at low concentration could help obtain sensitivity of gastric cancer cells to chemotherapy with significantly reduced cell viability. Interestingly, BIX combined Cis (BIX + Cis) treated SGC‐7901 cells display pyroptosis related cell death with large bubbles blown around the membrane, significantly decreased cell viability, elevated lactate dehydrogenase release and increased percentage of propidium iodide and Annexin‐V double positive cells. Furthermore, the cleavage of gasdermin E (GSDME) and caspase‐3 but not GSDMD was detected by immunoblotting and the knockout of GSDME switched pyroptosis into apoptosis in the BIX + Cis combined treated group. Furthermore, the deficiency of Beclin‐1 to inhibit BIX induced autophagic flux completely blocked BIX + Cis combined treated induced cell pyroptosis related cell death. Additionally, BIX + Cis in vivo treatment could inhibit tumor growth, which could be reversed by the deficiency of Beclin‐1 and be delayed by the deficiency of GSDME. In conclusion, our data was the first to reveal that BIX enhanced the anticancer chemotherapy effect by induced GSDME‐mediated pyroptosis through the activation of autophagic flux in gastric cancer cells. 相似文献
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999.
Xin Wang Zeming Qi Xingcun Liu Shengyi Wang Chengxiang Li Gang Liu Yin Xiong Tingting Li Jinqiu Tao Yangchao Tian 《Cancer epidemiology》2010,34(4):453-456
Objective: The objective is to apply synchrotron-based FTIR microspectroscopy and imaging to human hair tissue and investigate the possibility of the method in gastric cancer research and diagnosis. Methods: Human hair from gastric cancer patients’ scalp and normal persons’ scalp were studied by synchrotron-based FTIR microspectroscopy and imaging. Results: The micro-spectra and imaging show the difference between the normal and malignant hair tissues. Obvious peak shift of symmetric phosphate band is observed in micro-spectra of medulla region for the hair tissue of gastric cancer patients. Chemical imaging shows the distributions of lipid and amide II/vsPO2? have changed in the gastric cancer cases. Conclusions: The study indicates that the hair tissue's infrared microspectroscopy and imaging using synchrotron will be a potentially useful method for rapid early gastric cancer diagnosis. 相似文献
1000.
Seasonal Variation of Virioplankton in a Eutrophic Shallow Lake 总被引:5,自引:0,他引:5
Yan-Ming Liu Qi-Ya Zhang Xiu-Ping Yuan Zheng-Qiu Li Jian-Fang Gui 《Hydrobiologia》2006,560(1):323-334
Lake Donghu is a typical eutrophic freshwater lake in which high abundance of planktonic viruses was recently revealed. In
this study, seasonal variation of planktonic viruses were observed at three different trophic sites, hypertrophic, eutrophic,
and mesotrophic regions, and the correlation between their abundances and other aquatic environmental components, such as
bacterioplankton, chlorophyll a, burst size, pH, dissolved oxygen, and temperature, was analyzed for the period of an year. Virioplankton abundance detected
by transmission electron microscope (TEM) ranged from 5.48 × 108 to 2.04 × 109 ml−1 in all the sites throughout the study, and the high abundances and seasonal variations of planktonic viruses were related
to the trophic status at the sampled sites in Lake Donghu. Their annual mean abundances were, the highest at the hypertrophic
site (1.23×109 ml−1), medium at the eutrophic site (1.19×109 ml−1), and the lowest at the mesotrophic site (1.02×109 ml−1). The VBR (virus-to-bacteria ratio) values were high, ranging from 49 to 56 on average at the three sampled sites. The data
suggested that the high viral abundance and high VBR values might be associated with high density of phytoplankton including
algae and cyanobacteria in this eutrophic shallow lake, and that planktonic viruses are important members of freshwater ecosystems. 相似文献