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711.
An important challenge in antisense technology remains the adequate delivery of the oligonucleotides (ON) to individual cells. Understanding the subcellular distribution of ONs and their carrier is essential to explain the (lack of) biological activity. The ability of several cationic carriers to efficiently deliver anti-ICAM-1 oligonucleotides to their site of action was studied using a cell-based assay. In this assay we evaluated the ability of the ONs to downregulate the expression of the ICAM-1-protein in A549 cells. To understand why some carrier/ONs combinations showed biological activity while others failed, flow cytometry and confocal laser scanning microscopy (CLSM) measurements were used to study cellular uptake and intracellular distribution of the (fluorescently labeled) ONs. We showed that free ONs (both PS-ONs and PO-ONs) and ONs complexed to pEGpEI failed to decrease the ICAM-1 protein level. This was due to the inability of the (free or complexed) ONs to enter the cell, as shown by flow cytometry and CLSM. Flow cytometry and CLSM showed cellular uptake when PO-ONs and PS-ONs were complexed to graft-pDMAEMA and Lipofectin. However, while the uptake and intracellular localization seemed similar for ONs complexed to, respectively, graft-pDMAEMA and Lipofectin, the biological activity of the ONs was clearly dependent on their carrier: both PO-ONs and PS-ONs complexed to graft-pDMAEMA reduced the ICAM-1 expression; however, when complexed to Lipofectin only PS-ONs showed biological activity. Also, PS-ONs complexed to graft-pDMAEMA were more active than PO-ONs complexed to graft-pDMAEMA which could not be explained by the results from CLSM and flow cytometry. While the ICAM-1 assay proves whether a certain pharmaceutical carrier successfully delivers ONs or not, it does not answer the important question why one carrier is successful while another one fails. Also, our study shows that flow cytometry and CLSM, although useful techniques, failed to clearly explain the difference in transfection behavior between graft-pDMAEMA and Lipofectin. As ONs become susceptible to degradation by cytosolic DNase as soon as they are released from their carrier, one could argue that a better understanding of the time and (intracellular) place at which the dissociation of the complexes occurs could be crucial to fully explain our observations.  相似文献   
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IntroductionOver the past decades, children have been increasingly using screen devices, while at the same time their sleep duration has decreased. Both behaviors have been associated with excess weight, and it is possible they act as mutually reinforcing behaviors for weight gain. The aim of the study was to explore independent, prospective associations of screen time and sleep duration with incident overweight in a sample of European children.MethodsData from 4,285 children of the IDEFICS/I.Family cohort who were followed up from 2009/2010 to 2013/2014 were analyzed. Hours per day of screen time and of sleep duration were reported by parents at baseline. Logistic regression analyses were carried out in separate and mutually adjusted models controlled for sex, age, European country region, parental level of education, and baseline BMI z-scores.ResultsAmong normal weight children at baseline (N = 3,734), separate models suggest that every hour increase in screen time and every hour decrease in sleep duration were associated with higher odds of the child becoming overweight or obese at follow-up (OR = 1.16, 95% CI: 1.02–1.32 and OR = 1.23, 95% CI: 1.05–1.43, respectively). In the mutually adjusted model, both associations were attenuated slightly (screen time OR = 1.13, 95% CI: 0.99–1.28; sleep duration OR = 1.20, 95% CI: 1.03–1.40), being consistently somewhat stronger for sleep duration.Discussion/ConclusionBoth screen time and sleep duration increased the incidence of overweight or obesity by 13–20%. Interventions that include an emphasis on adequate sleep and minimal screen time are needed to establish their causal role in the prevention of overweight and obesity among European children.  相似文献   
714.
We investigated the potential of tumor-infiltrating immune cells (ICs) as predictive or prognostic biomarkers for cervical cancer patients. In total, 38 patients treated with (chemo)radiotherapy and subsequent surgery were included in the current study. This unique treatment schedule makes it possible to analyze IC markers in pretreatment and posttreatment tissue specimens and their changes during treatment. IC markers for T cells (CD3, CD4, CD8 and FoxP3), macrophages (CD68 and CD163) and B cells (CD20), as well as IL33 and PD-L1, were retrospectively analyzed via immunohistochemistry. Patients were grouped in the low score or high score group based on the amount of positive cells on immunohistochemistry. Correlations to pathological complete response (pCR), cause-specific survival (CSS) and metastasis development during follow-up were evaluated. In analysis of pretreatment biopsies, significantly more pCR was seen for patients with CD8 = CD3, CD8 ≥ CD4, positive IL33 tumor cell (TC) scores, IL33 IC < TC and PD-L1 TC ≥5%. Besides patients with high CD8 scores, also patients with CD8 ≥ CD4, CD163 ≥ CD68 or PD-L1 IC ≥5% had better CSS. In the analysis of posttreatment specimens, less pCR was observed for patients with high CD8 or CD163 scores. Patients with decreasing CD8 or CD163 scores between pretreatment and posttreatment samples showed more pCR, whereas those with increasing CD8 or decreasing IL33 IC scores showed a worse CSS. Meanwhile, patients with an increasing CD3 score or stable/increasing PD-L1 IC score showed more metastasis during follow-up. In this way, the intratumoral IC landscape is a promising tool for prediction of outcome and response to (chemo)radiotherapy.  相似文献   
715.
Background To report a well-documented case of both allergic contact dermatitis and occupational asthma due to chromate exposure in a 48-year-old floorer Methods and Results A 48-year-old floorer, occupationally exposed to cement and with a documented chromate contact dermatitis, reported dyspnea and wheezing after work. These conditions were demonstrated by self-measured sequential peak expiratory flows. A first bronchial provocation test (BPT) with potassium dichromate (K2Cr2O7) (0.3% nebulized for a total of 60 minutes) led to pronounced and sustained decreases in forced expiratory volume in 1 second (FEV1) and forced vital capacity, accompanied by pruritus, a decrease in arterial PO2, a slight rise in temperature, and peripheral blood leukocytosis. (This concentration of K2Cr2O7 is not recommended for BPT). Bronchoalveolar lavage performed 2 days later showed 18% eosinophils. Two years later, a BPT with a lower dose of K2Cr2O7 (0.01% for a total of 31 min) led to an “early late” reaction (FEV1 dropped by 29% compared with the initial FEV1 value), accompanied by pruritus. A BPT with dry cement, containing 12 ppm hexavalent chromium, was borderline (FEV1 dropped by 13%), and a similar result (FEV1 dropped by 14%) was obtained after smoking five cigarettes, laced with 10 mg of cement per cigarette. Conclusions This report illustrates that a subject, with allergic contact dermatitis to chromates, may develop a respiratory allergic reaction to an airborne source of this metal. The main novelty of our report is that the smoking of cigarettes contaminated with cement may have been a significant factor in the causation or elicitation of these reactions. Am. J. Ind. Med. 34:169–176, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
716.
Teaching point: An inflammatory pseudotumor can occur almost everywhere in the body and has nonspecific imaging findings.  相似文献   
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Radiation injury has a complex pathophysiology and can result in long-term impediment of the dermal barrier function. Historically, its treatment has been no different to that of thermal burns and it is not always possible to prevent an unpredictable and uncontrolled extension of the radiation-induced reactions. Non-invasive physical plasma (NIPP), a highly energised gas encompassing a combination of various reactive species, positively affects the key players involved in wound healing and proves to be a promising treatment option for chronic wounds and inflammatory skin disorders. Recent clinical evidence also suggests preliminary efficacy in radiation injury following therapeutic irradiation as a part of cancer therapy. Further research is warranted to also investigate the clinical value of NIPP in the context of unplanned or accidental radiation exposure, either as a topical treatment or possibly as an intraoperative procedure, to potentially improve the dermatological outcome and reduce symptoms in radiation victims.  相似文献   
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