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951.
The aim of this paper is to offer an ethical perspective on the use of non-human primates in neurobiological studies, using the Parkinson's disease (PD) as an important case study. We refer, as theoretical framework, to the 3R principle, originally proposed by Russell and Burch [Russell, W.M.S., Burch, R.L., 1959. The Principles of Humane Experimental Technique. Universities Federation for Animal Welfare Wheathampstead, England (reprinted in 1992)]. Then, the use of non-human primates in the study of PD will be discussed in relation to the concepts of Replacement, Reduction, and Refinement. Replacement and Reduction result to be the more problematic concept to be applied, whereas Refinement offers relatively more opportunities of improvement. However, although in some cases the 3R principle shows its applicative limits, its value, as conceptual and inspirational tool remains extremely valuable. It suggests to the researchers a series of questions, both theoretical and methodological, which can have the results of improving the quality of life on the experimental models, the quality of the scientific data, and the public perception from the non-scientist community.  相似文献   
952.
The prognosis of patients with hepatic metastasis from breast cancer treated with systemic or regional chemotherapy is disappointing. When technically feasible, liver resection offers the best results. Eighteen patients out of 22 submitted to laparotomy underwent radical liver resection. Median follow-up from liver resection was 36 months. The median time interval between breast cancer diagnosis and disease recurrence was 35 months. Median disease-free survival and overall survival from liver resection were 66 and 74 months, respectively. Median survival time from breast cancer surgery was 88.5 months. Surgical treatment of liver metastases should be carried out on young and older patients alike when site of metastases is the liver alone. Neoadjuvant treatment and preoperative diagnostic laparoscopy should be planned in future experience.  相似文献   
953.
Are men more likely than women to take into account a child’s facial resemblance to themselves when making hypothetical parental investment choices? The benefits of self-resemblance in decreasing relatedness uncertainty are larger in men than in women for direct descendants. However, they are identical in men and women for collateral relatives, such as siblings, cousins, nephews, and nieces; these individuals can also be the recipients of parental-like altruism, which comes primarily from women. Published data are contradictory. In the present study, 14 men and 14 women were shown child faces and asked to judge their attractiveness, adoptability, and familiarity. The faces had been digitally manipulated to resemble (at three different resemblance levels, two of which were under recognition threshold) either the experimental participant, an acquaintance, or strangers. We found a significant preference for self-resemblant children in women, but not in men. This was not an artefact of women being better at detecting self-resemblance, given that at the highest resemblance level more men than women recognized themselves. Overall, face preference increased with face familiarity; for self-resemblant faces, this correlation was not mediated by conscious self-recognition. We discuss how the fast-response, multiple-question procedure used in previous experiments may have led to reports of a much larger self-resemblance preference in men than in women.  相似文献   
954.
BACKGROUND: Docetaxel-based chemotherapy is the only treatment that demonstrated an overall survival benefit in men with hormone refractory prostate cancer. 2-CADO inhibits the growth of PC3 cells by inducing apoptosis and cell cycle arrest through a mechanism that involves cellular uptake. METHODS: Androgen-independent and -sensitive (PC3 and LNCaP) prostate cancer cells and non-neoplastic HECV cells were used in the study. Proliferation and cell cycle progression were analyzed in the presence of 2-CADO and Docetaxel. Invasive potential was assessed by soft agar assay and metastatic ability by adhesion assay. IL-23 and PAR-1 expression were determined by real time PCR. RESULTS: 2-CADO pre-treatment followed by Docetaxel at subclinical dosage reduced the viability of either PC3 or LNCaP while it did not enhance Docetaxel-induced cytotoxicity in adherent non-neoplastic HECV. The drugs reduced the invasive potential of PC3 cells by inducing apoptosis and blocking cell cycle progression in the S-phase. Down-regulation of PAR-1 gene expression resulted in a slightly lower metastatic potential, whereas up-regulation of IL-23 induced the activation of the immune system. CONCLUSIONS: Pretreatment of PC3 cells with 2-CADO decreased the effective concentration of Docetaxel, lowered the metastatic potential, and induced the production of cytokines known to stimulate the immune response against cancer. The treatment was effective for prostate cancer cells independently on their androgen sensitiveness.  相似文献   
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956.
Growing interest in stem cell research has led to the development of a number of new methods for isolation. The lack of homogeneity in stem cell preparation blurs standardization, which however is recommended for successful applications. Among stem cells, mesenchymal stem cells (MSCs) are promising candidates for cell therapy applications. This paper presents a fractionation protocol based on a tag-less, flow-assisted method of purifying, distinguishing and sorting MSCs. The protocol entails a suspension of cells in a transport fluid being injected into a ribbon-like capillary device by continuous flow. In a relatively short time (about 30 min) sorted cells are collected. The protocol has been applied to the improvement of MSC isolation, with a specific view to reducing cell manipulation operations, keeping instrumental simplicity and increasing analytical information for cell characterization. Applications such as MSC purification from epithelial contaminants, MSC characterization from various human sources and sorting of MSC subpopulations with high differentiation potential are described. The low cost, full biocompatibility and scale-up potential of the protocol presented could make the procedure attractive for stem cell selection.  相似文献   
957.
958.
Sirolimus-eluting stents (SESs) reduce the rate of in-stent restenosis in selected cases. Their performance in more complex patients and their impact on the final clinical outcome of these patients, however, remains uncertain. RESTEM Registry (REgistro delle PCI in era di STEnt Medicati), a prospective multicenter registry collecting all percutaneous coronary interventions (PCIs) performed over 20 months and monitored up to 2 years, includes 5524 consecutive patients treated with bare metal stent (BMS) (72%), sirolimus-eluting stent (SES) (15%), combined BMS+SES (4%), or other techniques (9%). The combination of death, acute myocardial infarction (AMI), unstable angina and revascularizations had been chosen as primary endpoint. One-year multivariate analysis shows no significant advantage of SES in combined clinical events, a slight benefit in primary endpoint [18.5 vs. 25.0% BMS=odds ratio (OR) 0.78) and revascularizations (13.6 vs. 20.4% BMS=OR 0.74], a consistent advantage when only target vessel revascularizations (TVRs) are considered (5.5 vs. 10.5% BMS=OR 0.52). The two-year adjusted results confirm a significant advantage of SES in TVR (8.3 vs. 13.7% BMS=OR 0.65), a slight benefit for revascularizations (18.3 vs. 25.6% BMS=OR 0.76), without reducing mortality and other clinical events; these data refute the benefit on primary endpoint observed at 12 months (25.8 vs. 32.4% BMS=OR 0.84). After analyzing events recorded during the first and second year follow-up periods separately, the incidence of many of them favors SES in the first year, yet appear independent of the technique utilized in the second. RESTEM results confirming SES's capacity to reduce TVR without reduction of other clinical events, suggest that this advantage is limited to the first year after PCI, and show no evidence of excess of deaths, AMIs and late thrombosis following SES implantation described in recent meta-analyses.  相似文献   
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960.
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