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991.
Forearm reactive hyperemia and mortality in end-stage renal disease   总被引:7,自引:0,他引:7  
BACKGROUND: Reports on the general population indicated that decreased endothelial-mediated vasodilation has a prognostic impact on cardiovascular (CV) morbidity and mortality. Flow-dependent vasodilation of conduit arteries and ischemia-induced forearm reactive hyperemia are impaired in end-stage renal disease (ESRD). Whether deterioration of vasodilator function in ESRD patients has a prognostic impact has not been documented. The aim of this study was to determine whether the impaired forearm postischemic vasodilation is an independent predictor of mortality in ESRD patients, independently from CV end-organ damages, which are usually associated with decreased vasodilatory response. METHODS: Common carotid artery intima-media thickness (CCA-IMT), aortic stiffness (pulse wave velocity-PWV), and LV mass (LVM) were determined for 78 stable ESRD patients on hemodialysis. Forearm postischemic vasodilation [flow debt repayment (FDR)] was measured by venous plethysmography. All-cause mortality served as the outcome variable over a median follow-up of 60 +/- 27 months. RESULTS: Twenty-four deaths occurred (16 of CV origin). According to Cox regression adjusted for age, CCA-IMT, LVM, and PWV, all-cause mortality was independently associated with decreased FDR (RR 0.69 for every 10% increase; 95% CI 0.56-0.85; P= 0.0006) and increased aortic PWV (RR 1.16 for 1 m/s increase; 95% CI 1.04-1.29; P= 0.0091). CONCLUSION: Our data indicate that lower postischemic forearm reactive hyperemia is associated with all-cause mortality of ESRD patients, independently of the presence of end-organ damage such as LVH or arteriosclerosis.  相似文献   
992.
993.

Purpose

Syrah red grapes are used in the production of tannin-rich red wines. Tannins are high molecular weight molecules, proanthocyanidins (PAs), and poorly absorbed in the upper intestine. In this study, gut microbial metabolism of Syrah grape phenolic compounds was investigated.

Methods

Syrah grape pericarp was subjected to an enzymatic in vitro digestion model, and red wine and grape skin PA fraction were prepared. Microbial conversion was screened using an in vitro colon model with faecal microbiota, by measurement of short-chain fatty acids by gas chromatography (GC) and microbial phenolic metabolites using GC with mass detection (GC–MS). Red wine metabolites were further profiled using two-dimensional GC mass spectrometry (GCxGC-TOFMS). In addition, the effect of PA structure and dose on conversion efficiency was investigated by GC–MS.

Results

Red wine exhibited a higher degree of C1–C3 phenolic acid formation than PA fraction or grape pericarp powders. Hydroxyphenyl valeric acid (flavanols and PAs as precursors) and 3,5-dimethoxy-4-hydroxybenzoic acid (anthocyanin as a precursor) were identified from the red wine metabolite profile. In the absence of native grape pericarp or red wine matrix, the isolated PAs were found to be effective in the dose-dependent inhibition of microbial conversions and short-chain fatty acid formation.

Conclusions

Metabolite profiling was complementary to targeted analysis. The identified metabolites had biological relevance, because the structures of the metabolites resembled fragments of their grape phenolic precursors or were in agreement with literature data.  相似文献   
994.
995.

Purpose

The results of stress myocardial perfusion SPECT could be enhanced by new cadmium-zinc-telluride (CZT) cameras, although differences compared to the results with conventional Anger cameras remain poorly known for most study protocols. This study was aimed at comparing the results of CZT and Anger SPECT according to various study protocols while taking into account the influence of obesity.

Methods

The study population, which was from three different institutions equipped with identical CZT cameras, comprised 276 patients referred for study using protocols involving 201Tl (n?=?120) or 99mTc-sestamibi injected at low dose at stress (99mTc-Low; stress/rest 1-day protocol; n?=?110) or at high dose at stress (99mTc-High; rest/stress 1-day or 2-day protocol; n?=?46). Each Anger SPECT scan was followed by a high-speed CZT SPECT scan (2 to 4 min).

Results

Agreement rates between CZT and Anger SPECT were good irrespective of the study protocol (for abnormal SPECT, 201Tl 92 %, 99mTc-Low 86 %, 99mTc-High 98 %), although quality scores were much higher for CZT SPECT with all study protocols. Overall correlations were high for the extent of myocardial infarction (r?=?0.80) and a little lower for ischaemic areas (r?=?0.72), the latter being larger on Anger SPECT (p?<?0.001). This larger extent was mainly observed in 50 obese patients who were in the 201Tl or 99mTc-Low group and in whom stress myocardial counts were particularly low with Anger SPECT (228?±?101 kcounts) and dramatically enhanced with CZT SPECT (+279?±?251 %).

Conclusion

Concordance between the results of CZT and Anger SPECT is good regardless of study protocol and especially when excluding obese patients who have low-count Anger SPECT and for whom myocardial counts are dramatically enhanced on CZT SPECT.
  相似文献   
996.
ObjectiveIntrauterine insemination (IUI) is a commonly used treatment for infertility. Optimal timing of insemination is achieved either by ultrasound monitoring of follicular growth followed by the administration of human chorionic gonadotropin (hCG) or by the detection of a luteinizing hormone (LH) surge through urinary LH testing (uLH). However, in cycles where follicular growth is monitored, there is a possibility of a premature LH rise which may affect the outcome of treatment. The objective of the current study was to determine the frequency of spontaneous LH surges in ultrasound-monitored IUI cycles.MethodsOne hundred IUI cycles were followed for this prospective cohort study In combination with ultrasound monitoring, uLH testing was performed twice daily. A serum LH test was performed in the case of an inconclusive uLH test result. IUI was performed either on the day after a positive LH test or, if the diameter of the dominant follicle reached 18 mm and the LH test was still negative, 36 hours after ovulation triggering by administration of hCG.ResultsOf the 87 analyzed cycles, 19 (21.8%) exhibited a premature LH surge as detected by urine testing. Eleven further cycles had an inconclusive urine result, and in six of these (6.9% of cycles) the result was confirmed positive by serum LH testing, giving a total of 25 cycles (28.7%) experiencing a premature LH surge.ConclusionA considerable proportion of patients undergoing ultrasound-monitored IUI cycle had a spontaneous LH surge before ovulation triggering was scheduled This could affect pregnancy rates following IUI.  相似文献   
997.
Diagnosis of primary central nervous system lymphoma (PCNSL) is challenging, and although brain biopsy remains the gold standard, cerebrospinal fluid (CSF) constitutes a less invasive source of lymphomatous biomarkers. In a retrospective cohort of 54 PCNSL cases tested at diagnosis or relapse, we evaluated the contribution of immunoglobulin heavy chain (IGH) gene clonality and MYD88 L265P detection on both CSF cell pellets and supernatants, in comparison with cytology, flow cytometry, interleukin (IL)-10 and IL-6 quantification. Clonality assessment included a new assay to detect partial IGH-DJ rearrangements. Clonal IGH rearrangements and/or MYD88 L265P mutation were detected in 27 (50%) cell pellets and 24 (44%) supernatant cell-free (cf) DNA. Combining analyses on both compartments, 36 (66%) cases had at least one detectable molecular marker, present only in cfDNA for 9 (16%) of them. While cytology and flow cytometry were positive in only 7 (13.0%) and 9 (17.3%) cases respectively, high IL-10 levels were observed in 36 (66.7%) cases. Overall, taking into account molecular and cytokine results, 46/54 (85%) cases had at least one lymphomatous biomarker detectable in the CSF. These results show that this combination of biomarkers evaluated on both cell pellet and supernatant CSF fractions improves significantly the biological diagnosis of PCNSL.  相似文献   
998.
999.
Agricultural land use may influence macroinvertebrate communities by way of pesticide contamination associated with agricultural runoff. However, information about the relation between runoff-related pesticides and communities of benthic macroinvertebrates in stormwater wetland that receive agricultural runoff does not currently exist. Here we show changes in macroinvertebrates communities of a stormwater wetland that collects pesticide-contaminated runoff from a vineyard catchment. Sixteen runoff-associated pesticides, including the insecticide flufenoxuron, were continuously quantified at the inlet of the stormwater wetland from April to September (period of pesticide application). In parallel, benthic macroinvertebrate communities, pesticide concentrations, and physicochemical parameters in the wetland were assessed twice a month. Twenty-eight contaminated runoffs ranging from 1.1 to 114 m3 entered the wetland during the study period. Flufenoxuron concentrations in runoff-suspended solids ranged from 1.5 to 18.5 μg kg−1 and reached 6 μg kg−1 in the wetland sediments. However, flufenoxuron could not be detected in water. The density, diversity, and abundance of macroinvertebrates largely varied over time. Redundancy and formal concept analyses showed that concentrations of flufenoxuron, vegetation cover, and flow conditions significantly determine the community structures of stormwater wetland macroinvertebrates. This study shows that flow conditions, vegetation cover, and runoff-related pesticides jointly affect communities of benthic macroinvertebrates in stormwater wetlands.  相似文献   
1000.
Journal of Neuro-Oncology - Mucosae-associated lymphoid tissue (MALT) lymphomas are a rare and poorly understood form of primary central nervous system lymphoma (PCNSL). The aim of this study was...  相似文献   
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