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991.
Mamdooh Ghoneum Heba Allah M. Elbaghdady Abdallah A. El-Shebly Deyu Pan Edward Assanah Greg Lawson 《Journal of radiation research》2013,54(5):852-862
Hydroferrate fluid, MRN-100, an iron-based compound derived from bivalent and trivalent ferrates, is a potent antioxidant compound. Therefore, we examined the protective effect of MRN-100 against γ-radiation-induced lethality and damage to hematopoietic tissues in fish. A total of 216 Nile tilapia fish (Oreochromis niloticus) were randomly divided into four groups. Group 1 served as a control that was administered no radiation and no MRN-100 treatment. Group 2 was exposed only to γ-radiation (15 Gy). Groups 3 and 4 were pre-treated with MRN-100 at doses of either 1 ml/l or 3 ml/l in water for 1 week, and subsequently exposed to radiation while continuing to receive MRN-100 for 27 days. The survival rate was measured, and biochemical and histopathological analyses of hematopoietic tissues were performed for the different treatment groups at 1 and 4 weeks post-radiation. Exposure to radiation reduced the survival rate to 27.7%, while treatment with MRN-100 maintained the survival rate at 87.2%. In addition, fish exposed to γ-radiation for 1 week showed a significant decrease in the total number of white blood cells (WBCs) and red blood cells (RBCs) series. However, treatment with MRN-100 protected the total WBC count and the RBCs series when compared with irradiated fish. Furthermore, significant histological lesions were observed in the hepatopancreas, spleen and gills of irradiated fish. However, treatment with MRN-100 protected the histopathology of various organs. We conclude that MRN-100 is a radioprotective agent in fish and may be useful as an adjuvant treatment to counteract the adverse side effects associated with radiation exposure. 相似文献
992.
Estimating the effects of small doses of ionising radiation on DNA is one of the most important problems in modern biology. Different cytogenetic methods exist to analyse DNA damage; the cytokinesis-block micronucleus assay (CBMN) for human peripheral blood lymphocytes is a simple, cheap and informative cytogenetic method that can be used to detect genotoxic-related markers. With respect to previous studies on radiation-induced genotoxicity, children are a poorly studied group, as evidenced by the few publications in this area. In this study, we assessed radon genotoxic effects by counting micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in the lymphocytes of children who are long-term residents from areas with high radon concentrations. In the exposed group, radon was found to cause significant cytogenetic alterations. We propose that this method can be employed for biomonitoring to screen for a variety of measures. 相似文献
993.
Yanrong Guo Changfeng Dong Haoming Lin Xinyu Zhang Huiying Wen Yuanyuan Shen Tianfu Wang Siping Chen Yingxia Liu Xin Chen 《Ultrasound in medicine & biology》2017,43(11):2619-2628
The aim of this study is to evaluate the utility of acoustic radiation force impulse (ARFI) elastography for assessing hepatic fibrosis stage and non-alcoholic fatty liver disease (NAFLD) severity, as well as the relationship among hepatic histologic changes using shear wave velocity (SWV). Animal models with various degrees of NAFLD were established in 110 rats. The right liver lobe was processed and embedded in a fabricated gelatin solution (porcine skin). Liver mechanics were measured using SWV induced by acoustic radiation force. Among the histologic findings, liver elasticity could be used to differentiate normal rats from rats with simple steatosis (SS) as well as distinguish SS from non-alcoholic steatohepatitis (NASH), with areas under the receiver operating characteristic curves (AUROC) of 0.963 (95% confidence interval = 0.871–0.973) and 0.882 (95% confidence interval = 0.807–0.956), respectively. For NAFLD rats, the diagnostic performance of ARFI elastography in predicting significant fibrosis (F ≥ 2) had an AUROC of 0.963. For evaluating steatosis severity, we found a progressive increase in ARFI velocity proportional to steatotic severity in NAFLD rat models, but we observed no significant differences for steatotic severity after excluding the rats with fibrosis. ARFI elastography may be used to differentiate among degrees of severity of NAFLD and hepatic fibrotic stages in NAFLD rat models. 相似文献
994.
995.
目的 研究64层螺旋CT使用低剂量对比剂联合生理盐水在CTA中对脑动脉瘤的应用价值.方法 对临床疑有脑动脉瘤51例患者分为三组:甲组90ml对比剂不用生理盐水冲洗;乙组、丙组分别使用70ml、50ml对比剂之后用相同流速生理盐水40ml冲洗.对比剂流速为5.0ml/s.当颈内静脉显影的一刹那开始扫描.利用工作站软件进行图像处理,评估三组血管图像质量及动脉瘤显示情况.结果 三组病例动脉瘤的灵敏度、特异性在统计学上没有明显差异,甲组动静脉均显示很好,CT值较高.丙组动脉显示良好,静脉少,污染轻,血管CT值略低.乙组居于二者之间.结论 使用低剂量对比剂50ml+40ml生理盐水以5.0ml/s流率注射,不仅可以得到理想的图像,还是一种安全、快速、经济的检查方法. 相似文献
996.
Purpose: Ionizing radiation is one of the main modalities used in the treatment of colorectal cancer. Despite a number of epigenetic or non-targeted effects of radiation exposure that have been described, the effect of radiation on cell-cell adhesion in the epithelium has been less studied. We report morphological and molecular alterations induced by ionizing radiation at the junctional complex level of human colon cancer Caco-2 cells.Materials and methods: Cells were irradiated with doses of 2, 5 or 10 Gy and the effects on the junctional complex were monitored for different times after irradiation. Alterations of tight and adherens junction components were observed by measuring the transepithelial electrical resistance, by immunofluorescence and immunoblotting and electron microscopy analyses.Results: Ionizing radiation caused alterations in the junctional complex, as evidenced by: (a) a decrease in the transepithelial electrical resistance, (b) alterations in the pattern of the distribution of junctional proteins as observed for E-cadherin, occludin, and zonula occludens 1 (ZO-1), but with minor changes in claudin-1 localization, and (c) wide spaces between opposed cells. These effects were dose and time-dependent since minor doses of irradiation caused a reversible effect on E-cadherin distribution and transepithelial electrical resistance.Conclusions: The results obtained show that ionizing radiation caused redistribution of the main junctional proteins E-cadherin, occludin and ZO-1 with minor changes for claudin-1, leading to disassembly of the junctional complex and loss of its functionality in Caco-2 cells. The molecular mechanisms responsible for these events need further elucidation. 相似文献
997.
目的观察颈部肿瘤体积缩小及消瘦等因素导致的颈部组织结构的空间位移及放射剂量曲线覆盖靶区的变化。方法选取2017年1月~2018年3月期间我院收治的头颈部肿瘤分段调强放疗的50例患者,所有患者均需照射颈部肿瘤。研究患者首次CT定位图像及再次定位CT图像中颈部组织结构(包括肿瘤病灶)的空间位移及剂量曲线覆盖靶区的变化。结果第二阶段放疗计划的目标靶区界线相比与第一阶段放疗计划,在三维空间X、Y、Z轴位方向上移动度各不相同,X轴及Y轴方向上差异较为显著(P0.05),而Z轴方向上差异无统计学意义(P0.05)。结论实施分段调强放疗技术在治疗颈部肿瘤放疗中具有重要价值,为优化颈部肿瘤病灶的调强放疗技术提供依据,为临床医生对颈部肿瘤治疗时靶区的勾画提供具有更现实意义的参考依据。 相似文献
998.
《Brachytherapy》2018,17(5):734-741
PurposeTo determine the long-term results of a Phase II trial of perioperative high-dose-rate brachytherapy (PHDRB) in primary advanced or recurrent gynecological cancer.Methods and MaterialsFifty patients with locally advanced and recurrent gynecological cancer suitable for salvage surgery were included. Unirradiated patients (n = 25) received preoperative chemoradiation followed by surgery and PHDRB (16–24 Gy). Previously irradiated patients (n = 25) received surgery and PHDRB alone (32–40 Gy).ResultsMedian followup was 11.5 years. Eight unirradiated patients (32%) developed Grade ≥3 toxic events including two fatal events. Local and locoregional control rates at 16 years were 87.3% and 78.9%, respectively. Sixteen-year disease-free and overall survival rates were 42.9% and 46.4%, respectively. Ten previously irradiated patients (40.0%) developed Grade ≥3 adverse events, including four fatal events. Local and locoregional control rates at 14 years were 59.6% and 42.6%, respectively. Fourteen-year disease-free and overall survival rates were 16.0% and 19.2%, respectively.ConclusionsPHDRB allows effective salvage of a subset of unfavorable gynecological tumors with high-risk surgical margins. Toxicity was unacceptable at the initial dose levels but deescalation resulted in the absence of severe toxicity without a negative impact on locoregional control. A substantial percentage of patients remain alive and controlled at >10 years including a few previously irradiated cases with positive margins. 相似文献
999.
1000.
《Journal of the American College of Radiology》2018,15(8):1128-1132
Dual-energy CT offers several new applications and opportunities for routine clinical practice. Increasing utilization in the context of both routine practice and clinical research raises questions about expected radiation dose when compared with conventional single-energy exams. Despite initial concerns, advanced iterative reconstruction techniques and creation of virtual unenhanced images in multiphase acquisitions offer methods for dose reduction. Although dose varies across patients and scanners, modern dual-energy exams allow for comparable and potentially decreased radiation dose when compared with single-energy CT. In this review, we examine dual-energy radiation dose considerations with discussion of accepted ACR diagnostic reference levels. 相似文献