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1.
Recent event-related potential (ERP) studies revealed the selective processing of affective pictures. The present study explored whether the same phenomenon can be observed when pictures are presented only briefly. Toward this end, pleasant, neutral, and unpleasant pictures from the International Affective Pictures Series were presented for 120 ms while event related potentials were measured by dense sensor arrays. As observed for longer picture presentations, brief affective pictures were selectively processed. Specifically, pleasant and unpleasant pictures were associated with an early endogenous negative shift over temporo-occipital sensors compared to neutral images. In addition, affective pictures elicited enlarged late positive potentials over centro-parietal sensor sites relative to neutral images. These data suggest that a quick glimpse of emotionally relevant stimuli appears sufficient to tune the brain for selective perceptual processing.  相似文献   
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Purpose

[68Ga]Trishydroxypyridinone (THP)–prostate-specific membrane antigen (PSMA) is a novel tracer that can be labeled in one step by cold reconstitution of a kit with unprocessed generator eluate, targeting PSMA via the lysine-urea-glutamate (KuE) motif. The aim of this study was to evaluate the human imaging characteristics of [68Ga]THP-PSMA.

Procedures

[68Ga]THP-PSMA positron emission tomography (PET)/x-ray computed tomography (CT) was performed in 25 patients with biochemical recurrence after radical prostatectomy for prostate cancer. Urinary and biliary excretion and tumor lesion uptake were quantified using standardized uptake values (SUVs). Imaging characteristics were assessed in terms of non-target organ uptake, background activity, target-to-background ratios (TBRs) of tumor lesions, and frequency of bladder halo artifacts. Findings were compared to a matched cohort of 25 patients undergoing PET/CT with the established agent [68Ga]PSMA I&T.

Results

Physiologic uptake of [68Ga]THP-PSMA was significantly lower in salivary glands (P?<?0.0001), liver (P?<?0.0001), spleen (P?<?0.0001), and kidneys (P?<?0.0001) than with [68Ga]PSMA I&T. While biliary tracer excretion of [68Ga]THP-PSMA was negligible, urinary tracer excretion of [68Ga]THP-PSMA was fast, and significantly higher than for [68Ga]PSMA I&T, contributing to a higher frequency of bladder artifacts. Malignant lesion uptake of [68Ga]THP-PSMA assessed as either SUV or TBR was significantly lower than with [68Ga]PSMA I&T.

Conclusion

[68Ga]THP-PSMA yields suitable in vivo uptake characteristics. The simplified synthesis method for [68Ga]THP-PSMA may facilitate wider application and higher patient throughput with PSMA imaging. However, direct intraindividual comparison studies are needed to assess the relative performance of [68Ga]THP-PSMA vs other PSMA ligands in terms of clinical detection rate and image quality.
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OBJECTIVEEmerging data from animal and human pilot studies suggest potential benefits of glucagon-like peptide 1 receptor agonists (GLP-1RA) on lung function. We aimed to assess the association of GLP-1RA and chronic lower respiratory disease (CLRD) exacerbation in a population with comorbid type 2 diabetes (T2D) and CLRD.RESEARCH DESIGN AND METHODSA new-user active-comparator analysis was conducted with use of a national claims database of beneficiaries with employer-sponsored health insurance spanning 2005–2017. We included adults with T2D and CLRD who initiated GLP-1RA or dipeptidyl peptidase 4 inhibitors (DPP-4I) as an add-on therapy to their antidiabetes regimen. The primary outcome was time to first hospital admission for CLRD. The secondary outcome was a count of any CLRD exacerbation associated with an inpatient or outpatient visit. We estimated incidence rates using inverse probability of treatment weighting for each study group and compared via risk ratios.RESULTSThe study sample consisted of 4,150 GLP-1RA and 12,540 DPP-4I new users with comorbid T2D and CLRD. The adjusted incidence rate of first CLRD admission during follow-up was 10.7 and 20.3 per 1,000 person-years for GLP-1RA and DPP-4I users, respectively, resulting in an adjusted hazard ratio of 0.52 (95% CI 0.32–0.85). For the secondary outcome, the adjusted incidence rate ratio was 0.70 (95% CI 0.57–0.87).CONCLUSIONSGLP-1RA users had fewer CLRD exacerbations in comparison with DPP-4I users. Considering both plausible mechanistic pathways and this real-world evidence, potential beneficial effects of GLP-1RA may be considered in selection of an antidiabetes treatment regimen. Randomized clinical trials are warranted to confirm our findings.  相似文献   
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Parvoviridae is a family of small non-enveloped viruses and divided into two subfamilies. The family members infect a wide range of organisms from insects to humans and some of the members (e.g., nonpathogenic adeno-associated viruses) are effective gene therapy delivery vectors. We detailed the synonymous codon usage pattern of Parvoviridae family from the available 58 sequenced genomes through multivariate statistical methods. Our results revealed that nine viruses showed some degree of strong codon bias, and the others possessed a general weak trend of codon bias. ENc-plot and neutrality plot results showed that selective pressure dominated over mutation in shapes coding sequence’s composition. The overall GC content and GC content at the third synonymous codon position were the principal determinants behind the variations within the codon usage patterns, as they both significantly correlated with the first axis of correspondence analysis. In addition, gene length had no direct influence on the codon usage pattern. Densovirinae subfamily and Parvovirinae subfamily possessed nine identical preferred codons, though most of the two subfamilies codon usage frequencies were significantly different. The result of cluster analysis based on synonymous codon usage was discordant with that of taxonomic classification. Adeno-associated viruses formed a separated clade far from other Parvoviridae members in the dendrogram. Thus, we concluded that natural selection rather than mutation pressure accounts for the main factor that affects the codon bias in Parvoviridae family.  相似文献   
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Although concern has been raised about antipsychotic prescribing to youth with attention-deficit/hyperactivity disorder (ADHD), the available database is limited to individual studies. Therefore, in order to provide a synthesis of prevalence and time trends, we conducted a systematic review and pooled analysis of pharmaco-epidemiologic data on antipsychotic use in ADHD youth. Of 1806 hits, 21 studies (N) were retained that reported analyzable data for three separate populations: 1) antipsychotic-treated youth (N?=?15, n?=?341,586); 2) ADHD youth (N?=?9, n?=?6,192,368), and 3) general population youth (N?=?5, n?=?14,284,916). Altogether, 30.5?±?18.5 % of antipsychotic-treated youth had ADHD. In longitudinal studies, this percentage increased over time (1998–2007) from 21.7?±?7.1 % to 27.7?±?7.7 %, ratio?=?1.3?±?0.4. Furthermore, 11.5?±?17.5 % of ADHD youth received antipsychotics. In longitudinal studies, this percentage also increased (1998–2006) from 5.5?±?2.6 % to 11.4?±?6.7 %, ratio?=?2.1?±?0.6. Finally, 0.12?±?0.07 % of youth in the general population were diagnosed with ADHD and received antipsychotics. Again, in longitudinal studies, this percentage increased over time (1993–2007): 0.13?±?0.09 % to 0.44?±?0.49 %, ratio?=?3.1?±?2.2. Taken together, these data indicate that antipsychotics are used by a clinically relevant and increasing number of youth with ADHD. Reasons for and risk/benefit ratios of this practice with little evidence base require further investigation.  相似文献   
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