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31.
We describe a case of chronic fatigue syndrome (CFS) associated to Parvovirus B19 infection where administration of intravenous immunoglobulins (IVIG), previously reported as effective, induced a paradoxical clinical response and increased viral replication. The indication of IVIG administration in the treatment of Parvovirus B19-associated CFS should be carefully reconsidered.  相似文献   
32.
Viral and host factors leading to occult hepatitis B virus (HBV) infection (OBI) are not fully understood. Whether HBV genotype may influence the occurrence and course of OBIs is unknown. Here, we describe the case of a patient infected with HBV genotype A2 who developed symptomatic acute hepatitis and did not seroconvert after loss of HBsAg and HBeAg. The acute phase of hepatitis B was followed by a period of more than 2 years during which the DNA of an intergenotypic HBV/A2/G recombinant was intermittently detected in serum.  相似文献   
33.
Dynamic contrast material-enhanced magnetic resonance imaging (DCE-MRI) of breasts is an important imaging modality in breast cancer diagnosis with higher sensitivity but relatively lower specificity. The objective of this study is to investigate a new approach to help improve diagnostic performance of DCE-MRI examinations based on the automated detection and analysis of bilateral asymmetry of characteristic kinetic features between the left and right breast. An image dataset involving 130 DCE-MRI examinations was assembled and used in which 80 were biopsy-proved malignant and 50 were benign. A computer-aided diagnosis (CAD) scheme was developed to segment breast areas depicted on each MR image, register images acquired from the sequential MR image scan series, compute average contrast enhancement of all pixels in one breast, and a set of kinetic features related to the difference of contrast enhancement between the left and right breast, and then use a multi-feature based Bayesian belief network to classify between malignant and benign cases. A leave-one-case-out validation method was applied to test CAD performance. The computed area under a receiver operating characteristic (ROC) curve is 0.78 ± 0.04. The positive and negative predictive values are 0.77 and 0.64, respectively. The study indicates that bilateral asymmetry of kinetic features between the left and right breasts is a potentially useful image biomarker to enhance the detection of angiogenesis associated with malignancy. It also demonstrates the feasibility of applying a simple CAD approach to classify between malignant and benign DCE-MRI examinations based on this new image biomarker.  相似文献   
34.
Sensitive and reliable detection of mercury ions (Hg2+) and l-cysteine (l-Cys) is of great significance for toxicology assessment, environmental protection, food analysis and human health. Herein, we present gram-scale synthesis of nitrogen doped graphene quantum dots (N-GQDs) for sensitive detection of Hg2+ and l-Cys. The N-GQDs are one-step synthesized using bottom-up molecular fusion in a hydrothermal process with gram-scale yield at a single run. N-GQDs exhibit good structural characteristics including uniform size (∼2.1 nm), high crystallinity, and single-layered graphene thickness. Successful doping of N atom enables bright blue fluorescence (absolute photoluminescence quantum yield of 24.8%) and provides unique selectivity towards Hg2+. Based on the fluorescence quenching by Hg2+ (turn-off mode), N-GQDs are able to serve as an effective fluorescent probe for sensitive detection of Hg2+ with low limit of detection (19 nM). As l-Cys could recover the fluorescence of N-GQDs quenched by Hg2+, fluorescent detection of l-Cys is also demonstrated using turn-off-on mode.

One-step and gram-scale synthesis of nitrogen doped graphene quantum dots is realized for their sensitive detection of Hg2+ and l-Cys.  相似文献   
35.
Eosinophilia in the peripheral blood is classified as primary (clonal) hematologic neoplasms or secondary (nonclonal) disorders, associated with hematologic or nonhematologic disorders. This review focuses on the categories of hematolymphoid neoplasms recognized by the 2008 World Health Organization Classification of Tumours and Haematopoietic and Lymphoid Tissues that are characteristically associated with eosinophilia. We provide a systematic approach to the diagnosis of these neoplastic proliferations via morphologic, immunophenotypic, and molecular-based methodologies, and provide the clinical settings in which these hematolymphoid neoplasms occur. We discuss recommendations that eosinophilia working groups have published addressing some of the limitations of the current classification scheme.  相似文献   
36.
37.
目的考察大孔吸附树脂对白簕叶总多酚的吸附性能和纯化效果,寻找白簕叶总多酚纯化的较优工艺。方法采用Folin-Ciocalteu比色法定量,比较5种不同型号大孔吸附树脂对药食同源植物白簕叶中总多酚的吸附和解吸效果,从中筛选出适合分离纯化白簕叶总多酚的树脂,并对其吸附和解吸条件进行考察和优化。经过单因素实验,确定最终优化工艺。结果所得优化工艺为以质量浓度为1.0 mg/m L,pH值为3.0左右的白簕叶总多酚粗提液作为上样液,同时控制其体积流量为2.0m L/min,上样量控制为30 mL;然后以体积分数50%的乙醇水溶液洗脱,调节pH值为6.0,并控制洗脱体积流量为2.0 mL/min,洗脱量为40 mL。经HPD100型树脂纯化后,白簕叶多酚样品质量分数由纯化前的11.7%上升为49.7%,纯化效果为4.25倍。通过将HPD100型树脂进行扩大30倍实验证实:白簕叶多酚样品质量分数由纯化前的12.5%上升为54.5%,纯化效果为4.4倍,纯化效率并不随大孔树脂数量改变而改变。结论 HPD100为纯化白簕叶总多酚的最佳树脂,该工艺适合白簕叶总多酚的提取纯化工业生产。  相似文献   
38.
Zhao  Ruirui  Ma  Lina  Li  Shenggang  Luo  Minxia 《Cognitive computation》2022,14(6):1924-1941
Cognitive Computation - Three-way decision is a decision-making method based on human cognitive process, and its basic idea is to divide a universal set into three pair-wise disjoint regions to...  相似文献   
39.

Purpose

This study was designed to investigate the potential effect of bergapten on lipopolysaccharide (LPS)-mediated osteoclast formation, bone resorption and osteoclast survival in vitro.

Methods

After osteoclast precursor RAW264.7 cells were treated with bergapten (5, 20, 40 μmol/L) for 72 hours in the presence of LPS (100 ng/ml), osteoclastogenesis was identified by tartrate-resistant acid phosphatase (TRAP) staining, and the number of TRAP-positive multinucleated cells [TRAP(+)MNCs] per well were counted. To investigate the effect of bergapten on osteoclastic bone resorption, RAW264.7 cells were treated with bergapten for six days in the presence of LPS, and the area of bone resorption was analyzed with Image Pro-Plus. Next, we examined apoptosis of RAW264.7 cells after bergapten incubation for 48 hours by flow cytometer using annexin V/propidium iodide (PI) double labeling. Finally, osteoclast survival was observed by Hoechst 33342 labeling and Western blotting after bergapten treatment for 24 hours.

Results

Data showed that bergapten (5–40 μmol/L) dose-dependently inhibited LPS-induced osteoclast formation and bone resorption. Treatment with bergapten triggered apoptotic death of osteoclast precursor RAW264.7 cells in a dose-dependent manner. Furthermore, bergapten significantly reduced the survival of mature osteoclast, as demonstrated by emergence of apoptotic nuclei and activation of apoptotic protein caspase 3/9.

Conclusions

These findings suggest that bergapten effectively prevents LPS-induced osteoclastogenesis, bone resorption and survival via apoptotic response of osteoclasts and their precursors. The study identifies bergapten as an inhibitor of osteoclast formation and bone resorption and provides evidence that bergapten might be beneficial as an alternative for prevention and treatment of inflammatory bone loss.  相似文献   
40.
目的 建立福沙吡坦中痕量钯的测定方法,并验证除钯工艺的效果。方法 采用微波消解法处理样品,石墨炉原子吸收分光光度法测定福沙吡坦中钯的残留量。结果 钯质量浓度在5~50μg/L范围内与吸光度线性关系良好(r=0.999 9),检出限为1.68μg/L,样品中的最低检出浓度为0.22μg/g;方法平均回收率为100.82%,RSD=3.34%(n=9)。结论 采用该方法测定福沙吡坦中钯的残留量,方法灵敏、准确、可靠,为药品的质量控制提供了依据。  相似文献   
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