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991.
OBJECTIVES: We assessed the effect of administration time for fasudil treatment of the stunned myocardium in 40 anesthetized open chest swine. MATERIALS AND METHODS: All swine were subjected to 12 min ischemia followed by reperfusion to generate stunned myocardium. Group A (n = 11) received saline in place of fasudil both before ischemia and after reperfusion. Group B (n = 10) received 30 min intravenous fasudil at a rate of 13 mug/kg/min starting 45 min before ischemia and received saline after reperfusion. Groups C (n = 10) and D (n = 9) received saline before ischemia, and received fasudil at a rate of 13 mug kg(-1) min(-1) starting just before reperfusion in group C and 30 min after reperfusion in group D. In both groups, treatment lasted 30 min. Myocardial contractility was assessed by percent segment shortening (%SS). RESULTS AND DISCUSSION: Three swine in group A, 2 swine in each of groups B and C, and one swine in group D had ventricular fibrillation or tachycardia after reperfusion and were excluded from further analysis. The changes of %SS from baseline at 90 min after reperfusion in groups B and C were 68 +/- 8% and 75 +/- 8%, respectively, which were significantly higher than in group A or D (47 +/- 10% or 43 +/- 8%). CONCLUSION: We conclude that fasudil administered before ischemia or just after reperfusion, but not 30 min after reperfusion, protects the stunned myocardium.  相似文献   
992.

Purpose

Obstructive sleep apnea (OSA) is believed to be an important risk factor for gastroesophageal reflux disease (GERD). However, the association between OSA and GERD is not straightforward and has been incompletely characterized. The aim of this study was to assess the relationship between OSA and GERD by performing both polysomnography (PSG) and esophagogastroduodenoscopy (EGD).

Methods

The enrolled patients underwent both PSG and EGD from October 2003 to July 2015 at Seoul National University Bundang Hospital. All patients were checked for the presence of mucosal injury in the EGD findings and divided into a no-GERD group and a GERD group according to the Los Angeles (LA) classification. In addition, the GERD symptoms of heartburn, acid regurgitation, and reflux-related cough were recorded.

Results

A total of 216 patients were enrolled. Ninety-nine patients (45.8%) were in the GERD group, 68 (31.5%) were the minimal-change GERD group, and 49 (22.7%) were in the GERD LA-A/B group. The OSA-related findings were worse in the GERD LA-A/B group than in the no-GERD group: the apnea-hypopnea index was 33.6 ± 25.5 versus 22.0 ± 17.2 (p = 0.01), the longest apnea duration was 50.7 ± 24.0 versus 41.6 ± 23.3 s (p = 0.03), the lowest oxygen saturation was 80.2 ± 7.9 versus 83.2 ± 7.5% (p = 0.02), and the oxygen desaturation index was 25.1 ± 22.4 versus 16.1 ± 15.5 (p = 0.01), respectively. Sleep efficiency was significantly worse in patients with GERD symptoms (81.2 ± 10.8%) than in those without GERD symptoms (85.1 ± 11.4%) (p = 0.03).

Conclusions

Endoscopically proven GERD was associated with more severe OSA. GERD symptoms were also associated with deteriorated sleep quality.
  相似文献   
993.
ObjectivesThis study evaluated the physiologic characteristics of discordant lesions between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) and the prognosis at 5 years.BackgroundFFR or iFR have been standard methods for assessing the functional significance of coronary artery stenosis. However, limited data exist about the physiologic characteristics of discordant lesions and the prognostic implications resulting from these lesions.MethodsA total of 840 vessels from 596 patients were classified according to iFR and FFR; high iFR–high FFR (n = 580), low iFR–high FFR (n = 40), high iFR–low FFR (n = 69), and low iFR–low FFR (n = 128) groups, which were compared with a control group (n = 23). The differences in coronary circulatory indices including the coronary flow reserve (CFR), index of microcirculatory resistance (IMR), and resistance reserve ratio (RRR) (resting distal arterial pressure × mean transit time / hyperemic distal arterial pressure × hyperemic mean transit time), which reflect the vasodilatory capacity of coronary microcirculation, were compared. Patient-oriented composite outcomes (POCO) at 5 years including all-cause death, any myocardial infarction, and any revascularization were compared among patients with deferred lesions.ResultsIn the low iFR–high FFR group, CFR, RRR, and IMR measurements were similar to the low iFR–low FFR group: CFR 2.71 versus 2.43 (p = 0.144), RRR 3.36 versus 3.68 (p = 0.241), and IMR 18.51 versus 17.38 (p = 0.476). In the high iFR–low FFR group, the CFR, RRR, and IMR measurements were similar to the control group: CFR 2.95 versus 3.29 (p = 0.160), RRR 4.28 versus 4.00 (p = 0.414), and IMR 17.44 versus 17.06 (p = 0.818). Among the 4 groups, classified by iFR and FFR, CFR and RRR were all significantly different, except for IMR. However, there were no significant differences in the rates of POCO, regardless of discordance between the iFR and FFR. Only the low iFR–low FFR group had a higher POCO rate compared with the high iFR–high FFR group (adjusted hazard ratio: 2.46; 95% confidence interval: 1.17 to 5.16; p = 0.018).ConclusionsDifferences in coronary circulatory function were found, especially in the vasodilatory capacity between the low iFR–high FFR and high iFR–low FFR groups. FFR–iFR discordance was not related to an increased risk of POCO among patients with deferred lesions at 5 years. (Clinical, Physiological and Prognostic Implication of Microvascular Status; NCT02186093; Physiologic Assessment of Microvascular Function in Heart Transplant Patients; NCT02798731)  相似文献   
994.
995.
996.
BACKGROUND/AIMS: Although previous reports suggested that pepsinogen (PG) I/II ratio was the index of gastric atrophy, PG I/II ratio was also related to other factors such as Helicobacter pylori (H. pylori) infection, various gastrointestinal diseases, and aging. The aim of this study was to evaluate the relationship between serum PG I/II ratio and age or upper gastro-intestinal diseases according to H. pylori infection status. METHODS: A total of 529 individuals (307 male; mean age, 57.2 years) were divided into 4 groups (94 gastric ulcers, 35 duodenal ulcers, 105 reflux esophagitis, and 295 atrophic gastritis) according to endoscopic diagnosis. H. pylori infection was determined by H. pylori IgG antibody (ELISA) and PG was measured by latex immunoassay. RESULTS: H. pylori infected patients showed markedly increased serum PG II levels (24.0+/-14.7 ng/mL vs. 13.8+/-16.6 ng/mL, p0.001) and low PG I/II ratio (3.9+/-2.0 vs. 6.0+/-2.5, p0.001) than non-infected subjects. In H. pylori infected patients, mean PG I/II ratios in the gastric ulcer and atrophic gastritis group were significantly lower than those of the duodenal ulcer and reflux esophagitis group (p0.001, ANOVA, Turkey's multiples comparison test). The mean ratio of open type atrophic gastritis was lower than that of close type atrophic gastritis (3.0+/-1.4 vs. 3.8+/-1.7, p0.005). PG I/II ratio gradually decreased with age in H. pylori-infected patients with atrophic gastritis (R(2)=0.9, p=0.005, linear regression analysis). CONCLUSION: Serum PG I/II ratio reflects H. pylori infection and gastric atrophy. In the presence of H. pylori infection, gastric atrophy progresses with age.  相似文献   
997.
Kim WU  Lee SH  Shim BY  Min JK  Hong YS  Park SH  Cho CS  Park CK  Kim HY 《Lupus》2000,9(2):147-150
A 25-year-old girl presented with progressive deterioration of right side weakness with decreased sensation on the left trunk. She had been treated with high dose steroid due to autoimmune thrombocytopenia for 2 months. Clinical, laboratory and immunologic studies revealed that she had systemic lupus erythematosus (SLE), MRI of spinal cord showed marginal contrast enhancing and fluid containing mass in the cord of the C5-6 level, suggesting intramedullary abscess. She underwent surgery of mass removal with biopsy. The pathologic findings from cord tissues revealed numerous acid fast bacilli (AFB) in necrotic tissues. After surgery and anti-tuberculous treatment, her neurologic symptoms were markedly improved with restoration of right side motor weakness. To our knowledge, this is the first case report of intramedullary tuberculosis in a patient with SLE. Since intramedullary tuberculosis may sometimes mimic neurologic complication of SLE itself, it may pose diagnostic and therapeutic confusion for clinicians. We report a case of spinal cord tuberculosis affecting C5, 6 level which was manifested as Brown-Sequard syndrome in a patient with SLE.  相似文献   
998.

Objectives

To compare outcomes and rates of optimal stent placement between optical coherence tomography (OCT) and intravascular ultrasound (IVUS) guided percutaneous coronary intervention (PCI).

Background

Unlike IVUS‐guided PCI, rates of clinical outcomes and optimal stent placement have not been well characterized for OCT‐guided PCI.

Methods

The study enrolled 290 patients who underwent implantation of a second generation drug eluting stent under OCT (122 patients) or IVUS (168 patients) guidance. The two groups were compared after adjusting for baseline differences using 1:1 propensity score matching (PSM) (114 patients in each group). Optimal stent placement was defined as achieving an adequate lumen (optimal minimum stent area [MSA > 4.85 mm2 for OCT, >5 mm2 for IVUS] or a final MSA ≥ 90% of the distal reference lumen area, without edge dissection, incomplete stent apposition, or tissue prolapse), or otherwise performing additional interventions to address suboptimal post‐stenting OCT or IVUS findings. The primary endpoint was one‐year cumulative incidence of major adverse cardiac events (MACE; cardiac death, myocardial infarction and target lesion revascularization). Definite or probable stent thrombosis (ST) rates were evaluated.

Results

In adjusted comparisons between OCT and IVUS groups, there was no significant difference in rates of MACE (3.5% vs. 3.5%, P = 1.000) and ST (0% vs. 0.9%, P = 1.000) at 1 year, optimal stent placement (89.5% vs. 92.1%, P = 0.492), and further intervention (7.9% vs.13.2%, P = 0.234), despite OCT significantly more frequently detecting tissue prolapse (97.4% vs. 47.4%, P < 0.001), and numerically more edge dissection (10.5% vs. 4.4%, P = 0.078) or incomplete stent apposition (48.2% vs. 36.8%, P = 0.082).

Conclusions

OCT guidance showed comparable results to IVUS in mid‐term clinical outcomes, suggesting that OCT can be an alternative tool for stent placement optimization. (J Interven Cardiol 2016;29:216–224)
  相似文献   
999.
A soluble nitric oxide (NO) synthase activity was purified 426-fold from a mouse macrophage cell line activated with interferon gamma and bacterial lipopolysaccharide by sequential anion-exchange, affinity, and gel filtration chromatography. SDS/PAGE of the purified NO synthase gave three closely spaced silver-staining protein bands between 125 and 135 kDa. When assayed in the presence of L-arginine, NADPH, tetrahydrobiopterin, FAD, and reduced thiol, purified NO synthase had a specific activity of 1313 nmol of NO2- plus NO3- per min per mg. The apparent Km of the enzyme for L-arginine and NADPH was 2.8 and 0.3 microM, respectively. Addition of calcium ions with or without calmodulin did not increase the activity of the purified enzyme, and NO synthesis was not altered by calmodulin inhibitors. Gel filtration chromatography indicated that the induced NO synthase was catalytically competent as a dimer of approximately 250 kDa but could be dissociated into inactive monomers of approximately 130 kDa in the absence of L-arginine, FAD, and tetrahydrobiopterin. Upon heat denaturation, NO synthase released 1.1 mol of FAD and 0.55 mol of FMN per mol of 130-kDa subunit. Thus, inducible macrophage NO synthase differs in several respects from constitutive NO synthases and is one of very few eukaryotic enzymes containing both FAD and FMN.  相似文献   
1000.

Purpose

The time from puberty to the first pregnancy is known to be important for a woman’s life-time breast cancer risk. Recent studies suggest that epigenetic mechanisms may involve pubertal maturation processes, which can affect the risk of breast cancer in later life. Epigenetic alterations are related to lipotropes (methionine, choline, folate, and vitamin B12), which are methyl donors and cofactors. However, the effects of pubertal supplementation of lipotropes in breast cancer remain largely unknown.

Methods

Twenty female Sprague–Dawley rats, aged 6 weeks, were divided into two groups and fed a normal control diet or a lipotrope-fortified diet formulated to provide five times basal levels of lipotropes during puberty. All rats were injected intraperitoneally with N-nitroso-N-methylurea at 50 days of age to induce mammary tumors.

Results

Tumor multiplicity and tumor volume decreased significantly as a result of lipotrope supplementation. Interestingly, quantitative RT-PCR revealed significantly decreased expression of histone deacetylase 1 (Hdac1) and DNA methyltransferase 1 (Dnmt1) genes in tumor tissues of the rats supplemented with lipotrope-fortified diet, suggesting that reduced risk of breast cancer can be attributed, at least in part, to decreased expression of these two genes.

Conclusions

This study demonstrates that supplementation of lipotrope-fortified diet during puberty suppresses tumor growth, potentially through down-regulating Hdac1 and Dnmt1 gene expression. Our findings suggest that pubertal methyl diet plays an important role in the etiology of breast cancer, and further studies are warranted to develop preventative strategies against breast cancer.  相似文献   
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