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51.
Diet is one of the most important factors that influence the risks for cardiovascular diseases. Genistein, an isoflavone found in soy, may benefit the cardiovascular system. Here, we investigated the effect of genistein on platelet-derived growth factor (PDGF)-BB-induced proliferation of primary cultured rat aortic smooth muscle cells (RASMCs). Genistein significantly inhibited 25 ng/ml PDGF-BB-induced RASMC proliferation and [3H]-thymidine incorporation into DNA at 10, 20, and 40 microM. In accordance with these findings, genistein blocked the PDGF-BB-inducible progression through G0/G1 to S phase of the cell cycle in synchronized cells. Western blot analysis showed that genistein not only inhibited phosphorylation of retinoblastoma protein (pRb) and expression of cyclin E, cyclin-dependent kinase (CDK) 2, and proliferating cell nuclear antigen (PCNA) protein, but also inhibited downregulation of cyclin-dependent kinase inhibitor (CKI) p27kip1. However, genistein did not affect p21cip1, CDK4, and cyclin D1 expression or early signal transduction through PDGF beta-receptor, extracellular signal-regulated kinases 1/2 (ERK1/2), Akt, and phospholipase C (PLC) gamma1 phosphorylation. These results suggest that genistein inhibits PDGF-BB-induced RASMC proliferation via G0/G1 arrest in association with induction of p27kip1, which may contribute to the beneficial effects of genistein on the cardiovascular system.  相似文献   
52.
1. The in vitro metabolism of 3-((5-(6-methylpyridin-2-yl)-4-(quinoxalin-6-yl)-1H-imidazol-2-yl)methyl)benzamide (IN-1,130), a selective activin receptor-like kinase-5 (ALK5) inhibitor and a candidate drug for fibrotic disease, was studied. 2. The cytochrome P450s (CYPs) responsible for metabolism of IN-1,130 in liver microsomes of rat, mouse, dog, monkey and human, and in human CYP supersomestrade mark, were identified using specific CYP inhibitors. The order of disappearance of IN-1,130 in various liver microsomal systems studied was as follows: monkey, mouse, rat, human, and dog. 3. Five distinct metabolites (M1-M5) were identified in all the above microsomes and their production was substantially inhibited by CYP inhibitors such as SKF-525A and ketoconazole. Among nine human CYP supersomestrade mark examined, CYP3A4, CYP2C8, CYP2D6 1, and CYP2C19 were involved in the metabolism of IN-1,130, and the production of metabolites were significantly inhibited by specific CYP inhibitors. IN-1,130 disappeared fastest in CYP2C8 supersomes. CYP3A4 produced four metabolites of IN-1,130 (M1-M4), whereas supersomes expressing human FMO cDNAs, such as FMO1, FMO3, and FMO5, produced no metabolites. 4. Hence, it is concluded that metabolism of IN-1,130 is mediated by CYP3A4, CYP2C8, CYP2D6 1, and CYP2C19.  相似文献   
53.
ObjectivesTo develop and validate a new risk-of-bias tool for nonrandomized studies (NRSs).Study Design and SettingWe developed the Risk of Bias Assessment Tool for Nonrandomized Studies (RoBANS). A validation process with 39 NRSs examined the reliability (interrater agreement), validity (the degree of correlation between the overall assessments of RoBANS and Methodological Index for Nonrandomized Studies [MINORS], obtained by plotting the overall risk of bias relative to effect size and funding source), face validity with eight experts, and completion time for the RoBANS approach.ResultsRoBANS contains six domains: the selection of participants, confounding variables, the measurement of exposure, the blinding of the outcome assessments, incomplete outcome data, and selective outcome reporting. The interrater agreement of the RoBANS tool except the measurement of exposure and selective outcome reporting domains ranged from fair to substantial. There was a moderate correlation between the overall risks of bias determined using RoBANS and MINORS. The observed differences in effect sizes and funding sources among the assessed studies were not correlated with the overall risk of bias in these studies. The mean time required to complete RoBANS was approximately 10 min. The external experts who were interviewed evaluated RoBANS as a “fair” assessment tool.ConclusionsRoBANS shows moderate reliability, promising feasibility, and validity. The further refinement of this tool and larger validation studies are required.  相似文献   
54.
Melanoma is the leading cause of death from skin disease due to its propensity for metastasis. Studies have shown that integrin‐mediated focal adhesion kinase (FAK) signal pathway is implicated in cell proliferation, survival and metastasis of tumor cells. Our previous results indicated that diallyl trisulfide (DATS) provided its antimelanoma activity via inducing cell cycle arrest and apoptosis. The aim of this study was to explore DATS mediated antimetastatic effect and the corresponding mechanism in human melanoma A375 cells. We found that DATS exhibited an inhibitory effect on the abilities of migration and invasion in A375 cells under noncytotoxic concentrations analyzed by wound healing assays and Matrigel invasion chamber system. DATS attenuated invasion of A375 cells with characteristic of decreased activities and protein expressions of matrix metalloproteinase‐2 (MMP‐2) and MMP‐9. Moreover, DATS exerted an inhibitory effect on cell adhesion of A375 cells, which is in correlation with the change in integrin signaling pathway. Results of Western blotting showed that DATS decreased the levels of several integrin subunits, including α4, α5, αv, β1, β3 and β4. Subsequently, DATS induced a strong decrease in total FAK, phosphorylated FAK Tyr‐397,‐576, ?577, and disorganized F‐actin stress fibers, resulting in a nonmigratory phenotype. These results suggest that the antimetastatic potential of DATS for human melanoma cells might be due to the disruption of integrin/FAK signaling pathway.  相似文献   
55.
The dissolution anisotropy of paracetamol crystals grown in the presence and absence of the molecularly similar additive, p-acetoxyacetanilide (PAA) was studied under controlled conditions using a single crystal dissolution method in undersaturated aqueous solutions. Linear dissolution rates were determined for all the major habit faces by measuring their movement (regression) with time in a flow cell using a microscope. The rates of dissolution of particular faces of the pure material were distinctly different in crystals of different morphology grown at different supersaturations. The dissolution rates of [001] and [110] faces of crystals grown in the presence of PAA (6.02% w/w in solution) are higher than those of pure paracetamol. The results correlate with the distribution of strain in the crystal and support the concept that integral strain increases the solubility and hence the dissolution rate of the material. The mechanism of the dissolution process at the [001], [201;] and [110] faces was defined using optical microscopy and X-ray topography. At all undersaturations above 1% the dissolution studies yielded well developed, structurally oriented, etch pits on both [001] and [201;] faces while on the [110] face rough shallow etch pits were observed. On all three faces, this etch-pitting was considerably more widespread than the dislocation content of the sector and probably reflects a 2-dimensional nucleation process rather than a dislocation controlled mechanism.  相似文献   
56.
Children of alcoholics have increased risk for substance abuse problems. Self-medication of negative affect may be one developmental path to future substance abuse. Because the 146 young (adolescent) children of alcoholics in the current sample had not used enough abused substances to study substance use directly, the relation of substance abuse risk markers to negative affect was assessed. Because the D2 dopamine receptor (DRD2) A1 allele has been associated with alcoholism and other substance use disorders, negative affect, measured by the Beck Depression Inventory (BDI), was determined in four groups of children: boys and girls with the A1+ allele (A1A1 and A1A2 genotypes) and with the A1 allele (A2A2 genotype). The other risk markers were stress, low amplitude of the P300 evoked potential, poor visuospatial functioning, novelty seeking (NS), and harm avoidance (HA). Stress was correlated with BDI scores in all groups. In contrast, low P300 was associated with BDI scores only in boys with the A1+ allele (P = .04), NS was associated with BDI scores only in girls with the A1+ allele (P = .02), and HA was associated with BDI scores only in boys with the A1 allele (P = .01). In addition, boys with the A1+ allele had lower BDI (P = .05) and HA (P = .005) scores than the respective scores for boys with the A1 allele. Girls with the A1 allele had lower HA scores compared with scores for boys with the A1 allele (P = .02). Girls with the A1+ allele had lower visuospatial functioning than that of boys with the A1+ allele (P<.001). Results indicate that both sex and DRD2 genotype modify associations between negative affect and other substance abuse risk markers.  相似文献   
57.
1.?The in vitro metabolism of 3-((5-(6-methylpyridin-2-yl)-4-(quinoxalin-6-yl)-1H-imidazol-2-yl)methyl)benzamide (IN-1130), a selective activin receptor-like kinase-5 (ALK5) inhibitor and a candidate drug for fibrotic disease, was studied.

2.?The cytochrome P450s (CYPs) responsible for metabolism of IN-1130 in liver microsomes of rat, mouse, dog, monkey and human, and in human CYP supersomes?, were identified using specific CYP inhibitors. The order of disappearance of IN-1130 in various liver microsomal systems studied was as follows: monkey, mouse, rat, human, and dog.

3.?Five distinct metabolites (M1–M5) were identified in all the above microsomes and their production was substantially inhibited by CYP inhibitors such as SKF-525A and ketoconazole. Among nine human CYP supersomes? examined, CYP3A4, CYP2C8, CYP2D6*1, and CYP2C19 were involved in the metabolism of IN-1130, and the production of metabolites were significantly inhibited by specific CYP inhibitors. IN-1130 disappeared fastest in CYP2C8 supersomes. CYP3A4 produced four metabolites of IN-1130 (M1–M4), whereas supersomes expressing human FMO cDNAs, such as FMO1, FMO3, and FMO5, produced no metabolites.

4.?Hence, it is concluded that metabolism of IN-1130 is mediated by CYP3A4, CYP2C8, CYP2D6*1, and CYP2C19.  相似文献   
58.
Despite improvements in treatment, the 5-year survival for metastatic colorectal cancer remains poor. Novel approaches such as gene immunotherapy are being investigated to improve treatment. Retroviral gene transfer methods have been shown to transduce primary human T lymphocytes effectively resulting in the expression of therapeutic genes. However, a number of defects have been identified in T lymphocytes isolated from patients bearing tumour, which may have critical implications for the development of gene-targeted T cells as an anticancer therapy. To address this issue, primary T lymphocytes were isolated from patients with advanced colorectal cancer and tested for their ability to be transduced and to express subsequently a chimeric immune receptor consisting of a single-chain antibody fragment antigen-binding moiety specific for carcinoembryonic antigen (CEA) fused to the T cell receptor (TCR) CD3zeta chain. In 10 out of 10 patients, T lymphocytes were transduced, expanded in the absence of selection and tested for functional activity against CEA-expressing tumour cells. In each case, functional-specific cytotoxic activity was observed. Negligible activity was found in control cultures. This study highlights the feasibility of patient-derived T lymphocytes as a source of immune cells for autologous gene immunotherapy approaches.  相似文献   
59.
This study examined 11,333 rigid endoscopy procedures performed in the Department of Otolaryngology, National Taiwan University Hospital, during a 27-year period from 1970 to 1996. Among these cases, 3217 were performed to remove foreign bodies from the airway (459 cases, 14.3%) and esophagus (2758 cases, 85.7%). Retrospective analysis of these data revealed that peanuts (217 cases) and animal bones (1184 cases) were the most frequent foreign bodies encountered in the airway and esophagus, respectively. The successful rate of removal of these foreign bodies was 99.9% (3213/3217). The complication rate was only 0.2% (8/3217), and the mortality rate was less than 0.1% (2/3217). On the basis of these results, we conclude that foreign bodies in the airway and esophagus can be removed safely under direct visualization through rigid endoscopy with relatively few complications. A significant finding in this study is the declining trend in the number of cases in recent years. Despite the decline in the number of procedures, endoscopic removal of foreign bodies remains as a vital skill of the aerodigestive tract surgeon.  相似文献   
60.
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