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1.
European Journal of Clinical Microbiology & Infectious Diseases - Hemorrhagic fever with renal syndrome (HFRS) continues to be a cause of death in Europe. Our aim was to describe the clinical...  相似文献   
2.

Background

The conventional chemotherapy of colorectal cancer with irinotecan, 5-fluorouracil, and oxaliplatin remains one of the front-line treatments worldwide. However, its efficacy is quite low. Recently studies of the epithelial–mesenchymal transition (EMT) have become the focus of investigations into the cause of chemoresistance in several types of cancer, including colorectal cancer. The data about the role of EMT in chemosensitivity are controversial.

Materials and Methods

Human colon adenocarcinoma cell lines HT29 and HCT116 and 14 primary short-term cultures established from patient tumors were used. The chemosensitivity to irinotecan, 5-fluorouracil, and oxaliplatin was assessed using the (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. Immunocytochemistry, immunohistochemistry, and Western blot test were used to investigate the E-cadherin expression, the loss of which is a major hallmark of EMT.

Results

Elevated chemosensitivity of the cell line with EMT phenotype, HCT116, was demonstrated. Increased chemosensitivity was revealed in HT29 cell line upon EMT induction. E-cadherin–positive short-term cultures were more resistant to all the drugs tested, whereas each of E-cadherin–negative cultures showed sensitivity to at least one drug. The statistically significant dependency of cells viability on the E-cadherin expression (P < .04) was demonstrated on the short-term cultures using 2 concentrations of each drug.

Conclusion

The data obtained may serve as a basis for the analysis of colon cancer chemosensitivity using short-term cultures and the assay of E-cadherin expression.  相似文献   
3.
Abstract

The Janssen Autism Knowledge Engine (JAKE®) collects a large number of features from five biosensors across a range of tasks. The application of data mining methods to these data may be a useful approach to enable objective discrimination between autism spectrum disorder (ASD) and typically developing (TD) participants. Following a prospective observational study using JAKE, ASD participants classified as “moderate” or “severe” based on total scores on the Social Responsiveness Scale, and TD participants were used to build models, using repeated cross-validation, to identify biosensor features contributing to diagnosis. Four different models (partial least squares, random forest, elastic net, and C5.0) were chosen to build diagnostic classifiers using the training set, and the fitted models were evaluated on the test set. Model performance on the training set, based on receiver operating characteristics (ROC), was moderate (area under ROC curve = 0.61–0.72), and model performance on the test set based on kappa statistic was between 0.40 and 0.46 across the four models. Data mining methods applied to biosensor data can lead to models that discriminate ASD from TD. This method may prove useful in creating new diagnostic tests for ASD.  相似文献   
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Herein, the effect of architecture of stimuli‐responsive polymer brushes on the switching of colloidal particle adsorption is reported. Thermoresponsive copolymer brushes containing positively charged amino groups are used and investigated how negatively charged colloidal particles electrostatically adsorb onto them. The distribution of charged groups (block or random copolymer architecture) and the conformation of the polymer chains (extended or collapsed state) are varied. It is found that the strongest adsorption is achieved at high fractions of charged groups in the brushes, while the amount of adsorbed particles is independent of the polymer chain conformation; that is, the adsorption of particles cannot be switched. On the contrary to this, the most pronounced switching of adsorption is achieved at low fractions of charged/adhesive groups in the brushes when the adsorption of particles is weak. The lowest fraction of charged/adhesive groups (one group per few polymer chains) can be exclusively achieved by random copolymerization and not by block copolymers. An explanation of the adsorption behavior of colloidal particles on switchable brushes is proposed.  相似文献   
6.

Introduction

Untreated dental caries will eventually lead to pulpal inflammation. Although much is known regarding the interaction of microbial antigens and the immunologic defense systems of pulp, many aspects of the pathogenesis of pulpitis are not fully understood. The relationship between human pulp stem cells (HPSCs) and the pathogenesis of pulpitis remains among the poorly understood areas. Many of the invading bacteria are known to produce considerable amounts of hydrogen sulfide (H2S), which causes apoptosis in some tissues. The aims of this study were to determine whether H2S causes apoptosis in HPSCs and to examine its signaling pathway.

Methods

Stem cells were isolated from human dental pulp and incubated with 50 ng/mL H2S for 48 hours. To detect apoptosis, the cells were analyzed by using flow cytometry. The mitochondrial signaling pathway was examined by determining mitochondrial membrane depolarization. Activation of the key apoptotic enzymes caspase-9, caspase-8, and caspase-3 was assessed by using enzyme-linked immunosorbent assay. Release of cytochrome C from mitochondria was also determined.

Results

The number of apoptotic cells increased significantly with H2S treatment from 1.6% to 16.3% (P < .01). Significant increases were also measured in the amounts of caspase-9 and caspase-3 and in cytochrome C release (all P < .01) and in mitochondrial membrane depolarization (P < .05), whereas caspase-8 activity was not found.

Conclusions

H2S causes apoptosis in HPSCs by activating the mitochondrial pathway. It is suggested that H2S might be one of the factors modifying the pathogenesis of pulpitis by causing loss of viability of HPSCs through apoptosis.  相似文献   
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Parasitology Research - The purpose of the present study was to determine the prevalence of intestinal helminths and protozoa in colorectal cancer (CRC) patients and to evaluate the possible...  相似文献   
10.
The present study evaluated the prognostic role of circulating miRNA-618 in patients with metastatic colon cancer (mCC) and whether miR-618 gene rs2682818 single nucleotide polymorphisms (SNP) are associated with colon cancer susceptibility and expression levels of mature miR-618. In total, 104 patients with mCC before starting the chemotherapy were investigated. The expression status of circulating miR-618 in mCC was evaluated by quantitative PCR. TaqMan PCR assay was used for rs2682818 SNP genotyping. miR-618 was overexpressed in serum of mCC patients. Patients with high and intermediate expression of miR-618 had a significantly longer mean overall survival (OS) of 21 months than patients with low expression—16 months. In addition, multivariate Cox regression analysis confirmed the association between high/intermediate levels of miRNA-618 and longer OS, HR = 0.51, 95% CI: 0.30–0.86, p = 0.012. miR-618 rs2682818 SNP significantly decreased the risk of colon cancer susceptibility in both heterozygous codominant (AC vs. CC, OR = 0.39, 95% CI: 0.17–0.88, p = 0.024) and overdominant (AC vs. CC + AA, OR = 0.37, 95% CI: 0.16–0.85, p = 0.018) genetic models. Our data suggest that circulating miRNA-618 could be useful as a prognostic biomarker in mCC. Patients harboring AC rs2682818 genotype have a decreased risk for colon cancer in comparison with patients with CC and AA genotypes.  相似文献   
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