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991.
Live case presentations are increasingly common at interventional cardiology conferences. Taking advantage of significant advances in communication technology, broadcasts of procedures can be viewed as an extension of traditional medical education targeted to large groups of practitioners. However, there are important ethical, commercial, and patient safety issues associated with live cases that deserve attention. Use of investigational devices in live case demonstrations is subject to review and approval by FDA's Center for Devices and Radiological Health (CDRH), and the outcomes of patients participating in live cases are considered in the overall clinical study results. This article discusses CDRH's regulatory view of live case presentations with a focus on patient safety, clinical trial integrity, and concerns regarding improper medical device promotion. © 2010 Wiley‐Liss, Inc.  相似文献   
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BACKGROUND

Educating medical students about health disparities may be one step in diminishing the disparities in health among different populations. According to adult learning theory, learners’ opinions are vital to the development of future curricula.

DESIGN

Qualitative research using focus group methodology.

OBJECTIVES

Our objectives were to explore the content that learners value in a health disparities curriculum and how they would want such a curriculum to be taught.

PARTICIPANTS

Study participants were first year medical students with an interest in health disparities (n?=?17).

APPROACH

Semi-structured interviews consisting of 12 predetermined questions, with follow-up and clarifying questions arising from the discussion. Using grounded theory, codes were initially developed by the team of investigators, applied, and validated through an iterative process.

MAIN RESULTS

The students perceived negative attitudes towards health disparities education as a potential barrier towards the development of a health disparities curriculum and proposed possible solutions. These solutions centered around the learning environment and skill building to combat health disparities.

CONCLUSIONS

While many of the students’ opinions were corroborated in the literature, the most striking differences were their opinions on how to develop good attitudes among the student body. Given the impact of the provider on health disparities, how to develop such attitudes is an important area for further research.
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Physiological changes during pregnancy may change pharmacokinetics of compounds. Oxycodone is an increasingly used opioid agonist in acute pain management but its pharmacokinetics in labouring women has not been established. We studied the maternal pharmacokinetics and neonatal exposure of intravenous oxycodone for pain relief in the first stage of labour. The study was prospective, open‐labelled and with a control group. After informed consent, 15 nulliparous parturients and newborns, and newborns in a control group were studied. In the study group, oxycodone boluses of 1 mg i.v., up to a cumulative dose of 5 mg, was administered when labour pain score was 5/10 or higher. As the control group, 30 other newborns after uncomplicated deliveries with no systemic opioids were assessed for the neonatal outcome. In the study group, maternal pharmacokinetics of oxycodone was measured from plasma concentrations during labour, and neonatal exposure was assessed from umbilical plasma samples using population pharmacokinetic methods. Maternal plasma oxycodone concentration decreased with a median half‐life of 2.6 hr (range, 1.8–2.8). Oxycodone concentrations in the umbilical plasma 2.7 μg/l (0.3–14.5) were similar as in maternal plasma 2.4 (0.1–14.8) μg/l at the time of birth. No severe or unexpected adverse effects were noted. To conclude, firstly, maternal elimination half‐life of i.v. oxycodone was significantly shorter than that reported in non‐pregnant women, and secondly, maternal plasma oxycodone at the birth correlated well with neonatal umbilical concentrations and may, thus, be used as an estimate of neonatal exposure.  相似文献   
998.
Cutaneous squamous cell carcinoma (SCC) ranks second in the frequency of all skin tumors. Its incidence has risen significantly due to an increased sun exposure and the number of immunocompromised patients. It has a well-defined progression with known precursor lesions called actinic keratosis. The degree of cellular differentiation, tumor thickness, location, and other features has prognostic value. It has a better prognosis than mucosal SCC of the head and neck, also called head and neck squamous cell carcinoma (HNSCC).Ultraviolet light plays a fundamental role as an initiator and promoter of carcinogenesis of SCC, allowing the accumulation of genetic alterations that allows a selective growth advantage. The TP53 (p53) gene often mutates and Ras is frequently activated, but with low frequency of mutations. Normally, the extracellular signals determine whether the cells move from a quiescent state into an active proliferative state. In tumor cells an increase in the production of growth factors and its receptors can be often seen that gives rise to such an autocrine circuit facilitating cellular division. Recently, frequent mutations in the epidermal growth factor receptor (EGFR) have been detected in lung cancer, mainly deletions in exon 19 and L858R mutation in exon 21. These are located at the EGFR tyrosine kinase domain (TK). EGFR TK mutations produce activation of the signaling pathways downstream and preferentially activated antiapoptotic pathways (PI3K/AKT, JAK-STAT and ERK/MAPK). These mutations are correlated with the clinical response of patients to tyrosine kinase inhibitors (gefinitib and erlotinib), because the tumor cells are addicted to the constant activation of specific signaling pathways. Glioblastoma shows another EGFR mutation (EGFRvIII), corresponding to a deletion of the extracellular domain, and it is present in 24-67% of these tumors. This variant has been found in 42% of HNSCC, related to the poor response to monoclonal antibody cetuximab.Many observations show that there are abnormalities in the expression of epidermal growth factor receptor (EGFR) and/or its ligands in HNSCC with frequent activation of multiple pathways downstream EGFR, and unrelated to RAS mutation. This suggests the possibility of activation by mutation or overexpression of a component of the pathway located upstream-Ras. While in other tumors, especially lung cancer and glioblastoma, the EGFR mutations are frequent genetic events, it is unknown whether EGFR is mutated or amplified in SCC of the skin and what would be its pathogenic role in this malignancy and its precursors.  相似文献   
999.
Prostate cancer (PrCa) is the most common non-skin cancer diagnosed among males in developed countries and the second leading cause of cancer mortality, yet little is known regarding its etiology and factors that influence clinical outcome. Genome-wide association studies (GWAS) of PrCa have identified at least 30 distinct loci associated with small differences in risk. We conducted a GWAS in 2782 advanced PrCa cases (Gleason grade ≥ 8 or tumor stage C/D) and 4458 controls with 571 243 single nucleotide polymorphisms (SNPs). Based on in silico replication of 4679 SNPs (Stage 1, P < 0.02) in two published GWAS with 7358 PrCa cases and 6732 controls, we identified a new susceptibility locus associated with overall PrCa risk at 2q37.3 (rs2292884, P= 4.3 × 10(-8)). We also confirmed a locus suggested by an earlier GWAS at 12q13 (rs902774, P= 8.6 × 10(-9)). The estimated per-allele odds ratios for these loci (1.14 for rs2292884 and 1.17 for rs902774) did not differ between advanced and non-advanced PrCa (case-only test for heterogeneity P= 0.72 and P= 0.61, respectively). Further studies will be needed to assess whether these or other loci are differentially associated with PrCa subtypes.  相似文献   
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The orbitofrontal cortex (OFC) and basolateral nucleus of the amygdala (BLA) are important neural regions in responding adaptively to changes in the incentive value of reward. Recent evidence suggests these structures may be differentially engaged in effort and cue-guided choice behavior. In 2 T-maze experiments, we examined the effects of bilateral lesions of either BLA or OFC on (1) effortful choices in which rats could climb a barrier for a high reward or select a low reward with no effort and (2) effortful choices when a visual cue signaled changes in reward magnitude. In both experiments, BLA rats displayed transient work aversion, choosing the effortless low reward option. OFC rats were work averse only in the no cue conditions, displaying a pattern of attenuated recovery from the cue conditions signaling reward unavailability in the effortful arm. Control measures rule out an inability to discriminate the cue in either lesion group.  相似文献   
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