全文获取类型
收费全文 | 456篇 |
免费 | 16篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 19篇 |
妇产科学 | 15篇 |
基础医学 | 60篇 |
口腔科学 | 10篇 |
临床医学 | 44篇 |
内科学 | 81篇 |
皮肤病学 | 43篇 |
神经病学 | 43篇 |
特种医学 | 9篇 |
外科学 | 33篇 |
综合类 | 7篇 |
预防医学 | 28篇 |
眼科学 | 21篇 |
药学 | 30篇 |
肿瘤学 | 28篇 |
出版年
2024年 | 1篇 |
2023年 | 6篇 |
2022年 | 9篇 |
2021年 | 31篇 |
2020年 | 12篇 |
2019年 | 22篇 |
2018年 | 19篇 |
2017年 | 9篇 |
2016年 | 20篇 |
2015年 | 15篇 |
2014年 | 31篇 |
2013年 | 21篇 |
2012年 | 48篇 |
2011年 | 44篇 |
2010年 | 27篇 |
2009年 | 16篇 |
2008年 | 21篇 |
2007年 | 23篇 |
2006年 | 24篇 |
2005年 | 18篇 |
2004年 | 15篇 |
2003年 | 8篇 |
2002年 | 9篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有476条查询结果,搜索用时 15 毫秒
41.
42.
Variation in content of taxol and related taxanes in Eastern Himalayan populations of Taxus wallichiana 总被引:3,自引:0,他引:3
Extraction and analysis of paclitaxel and other taxanes in bark, needle leaves and stem segments of male and female plants of Taxus wallichiana, representing several populations, indicate that significant variation in taxane content exists within the population. Bark accumulated maximum amount of paclitaxel in almost all plants. Populations located at higher altitude tended to accumulate more paclitaxel than lower altitude plants. Seasons in which samples were collected and plant age have also been shown to affect paclitaxel accumulation. No effects of plant sex on paclitaxel content of the plants analyzed were observed. Significant differences in baccatin-III and 10-deacetylbaccatin III content were found to exist in the trees analyzed in this study. 相似文献
43.
Gontu Abhinay Scott Dessain Adabala Srikanth R.L. Senthilkumar Pitta Vidyasagar Alagangula Praveen R.V. Chandrasekhar Reddy Erri Swapna Reddy Lingala Rajendra 《Vaccine》2014
Although the World Health Organization recommends the use of in vitro techniques to qualify rabies vaccine lot release, very limited proposals have been made to arrive at a harmonized approach for wide scale usage. The present study proposed and evaluated the use of a novel avidin–biotin ELISA as an alternative to these in vivo tests in rabies vaccine manufacture. This assay utilized a neutralizing pan reactive monoclonal antibody (mAb) reactive with the conserved site-II of the natively folded rabies glycoprotein. Linear regression analysis of the in vitro glycoprotein estimates with the in vivo potency values, showed a good correlation (r2 = 0.8) with veterinary vaccines, but a poor correlation (r2 = 0.2) with human vaccines. However, we could qualitatively arrive at cut-off glycoprotein estimates from the ELISA, above which all the vaccines were declared to be protective by mouse challenge studies (>2.5 IU/dose). 相似文献
44.
45.
Cadmium (Cd) toxicity was studied in broilers, and efficacy of Emblica officinalis (500 ppm in feed), vitamin E (300 ppm in feed), and stressroak (1 g/kg feed) were evaluated for prophylactic and therapeutic management of Cd toxicity. One-day-old male broiler chicks were randomly divided into eight groups consisting of 10 chicks in each. Groups 1 and 2 were maintained as plain control and Cd (100 ppm in feed) toxic control (for six weeks). Groups 3, 4, and 5 were maintained on a combination of Cd (100 ppm in feed) and Emblica officinalis, vitamin E, and stressroak for six weeks. Groups 6, 7, and 8 were maintained with Cd for the first four weeks and on Emblica officinalis, vitamin E, and stressroak during the subsequent two weeks without Cd. Body weights, feed consumed, Feed conversion ratio (FCR), and glulathione (GSH) were significantly (P<0.05) decreased, whereas the activities of antioxidant enzymes (catalase and Superoxide dismutase (SOD)) and concentration of Thiobarbituric acid reacting substances (TBARS) were significantly (P<0.05) increased in toxic control group. After treatment with Emblica officinalis, vitamin E, and stressroak in groups 6, 7, and 8 during last two weeks and discontinuation of Cd, the parameters revealed improvement. From this study, it is concluded that Cd induces toxicity by oxidative stress, and supplementing Emblica officinalis, vitamin E, and stressroak in feed is useful in preventing and treating the toxicity. 相似文献
46.
Amod Patankar Rajesh Kshirsagar Swapna Patankar Sudhir Pawar 《Journal of maxillofacial and oral surgery》2016,15(2):270-273
This report demonstrates the clinical use of a modified, truly anatomic, root analogue zirconia implant for immediate replacement of a right mandibular first premolar. A 22-year-old female patient with chronic apical periodontitis of the right mandibular first premolar was referred and the tooth was carefully extracted. A truly anatomical, root identical, roughened zirconia implant modified by macro-retentions was manufactured and placed into the extraction socket by tapping 3 days later. After 4 months a composite crown was cemented in place. No complications occurred during the healing period. A good functional and aesthetic result was achieved with minimal bone resorption and soft tissue recession at 18 months follow-up. This report describes the successful clinical use of an immediate, single stage, truly anatomical root-analogue zirconia implant for replacement of a single rooted tooth. Significant modifications such as macro-retentions yielded primary stability and excellent osseointegration. This novel approach is minimally invasive, respects the underlying anatomy and aids socket prevention. In addition the procedure saves time and cost, has good patient acceptance as there is no need for osteotomy, sinus lift or bone augmentation. 相似文献
47.
Yogesh A. Sethi Aniruddha K. Kulkarni Supriya K. Khore Rajendra P. Panmand Sandip C. Kanade Suresh W. Gosavi Milind V. Kulkarni Bharat B. Kale 《RSC advances》2019,9(49):28525
The synthesis of Ag-nanoparticle-decorated CdMoO4 and its photocatalytic activity towards hydrogen generation under sunlight has been demonstrated. The CdMoO4 samples were synthesized by a simple hydrothermal approach in which Ag nanoparticles were in situ decorated on the surface of CdMoO4. A morphological study showed that 5 nm spherical Ag nanoparticles were homogeneously distributed on the surface of CdMoO4 particles. The UV/DRS spectra show that the band gap of CdMoO4 was narrowed by the incorporation of a small amount of Ag nanoparticles. The surface plasmonic effect of Ag shows broad absorption in the visible region. The enhanced photocatalytic hydrogen production activities of all the samples were evaluated by using methanol as a sacrificial reagent in water under natural sunlight conditions. The results suggest that the rate of photocatalytic hydrogen production using CdMoO4 can be significantly improved by loading 2% Ag nanoparticles: i.e. 2465 μmol h−1 g−1 for a 15 mg catalyst. The strong excitation of surface plasmon resonance (SPR) absorption by the Ag nanoparticles was found in the Ag-loaded samples. In this system, the role of Ag nanoparticles on the surface of CdMoO4 has been discussed. In particular, the SPR effect is responsible for higher hydrogen evolution under natural sunlight because of broad absorption in the visible region. The current study could provide new insights for designing metal/semiconductor interface systems to harvest solar light for solar fuel generation.Plasmonic enhancement of photocatalytic hydrogen generation is demonstrated using hierarchical Ag decorated CdMoO4 synthesized using a hydrothermal method. 相似文献
48.
Mandal Swapna; Shivapurkar Narayan M.; Galati Anthony J.; Stoner Gary D. 《Carcinogenesis》1988,9(7):1313-1316
The effect of ellagic acid (EA), a naturally occurring plantphenol, on the metabolism, DNA binding and DNA adduct formationof N-nitrosobenzylmethylamine (NBMA) in cultured explants ofrat esophagus was investigated. Explants were incubated in mediumcontaining EA at non-toxic concentrations of 10, 50 and 100µM for 16 h, followed by the addition of 1 µM [3H]NBMAand EA for 12 h. Explant DNA was isolated by phenol extractionand hydroxylapatite chromatography, and benzaldehyde formationwas determined by HPLC analysis of the culture medium. EA produceda significant inhibition in the total covalent binding of NBMAmetabolites to DNA and in the production of benzaldehyde inthe medium. After acid hydrolysis of the isolated DNA, the NBMA-DNAadducts were separated by HPLC. EA caused a dose-dependent decreasein the formation of N7-methylguanine and O6-methylguanine adducts.These results suggest that EA inhibits both the metabolism ofNBMA and the binding of NBMA metabolites to DNA in culturedrat esophagus. 相似文献
49.
50.
Xiao-Hong Yao H. Sugihara Takanori Hattori Kanade Katsura Tetsuro Takamatsu 《Virchows Archiv : an international journal of pathology》1998,433(3):275-280
In gastrointestinal epithelia, apoptosis has been thought to play a part in the shedding of postmitotic cells into the lumen. However, we have found that apoptosis more frequently in the generative cell (G) zone (the lower one third of the pit) than in the luminal zone (the upper one third of the pit) and the gland zone in the canine pyloric gland. To analyse the regulation of apoptotic cell death in each zone, we labelled S-phase cells by single and repeated injections of bromodeoxyuridine (BrdU) IV at intervals of 8 h. We found that 30% of apoptoses in the G zone were flash-labelled by BrdU and might derive from cells in or just after the S phase. The incidence of apoptosis and mitotic index did not change significantly after repeated injections of BrdU until the 49-h point, when the incidence of apoptosis increased and the mitotic index decreased significantly in the G zone, while the incidence of apoptosis decreased in the luminal zone. The BrdU-induced increase of apoptosis and cell-cycle arrest at the 49-h point may be caused by enhanced DNA mispairs that are elicited by incorporation of BrdU, in particular using the template of BrdU incorporated DNA. Apoptosis in the luminal zone may be down-regulated by reduced cell production in the G-zone. 相似文献