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101.
ObjectivesThe aim of this study was to investigate the impact of post–percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) on clinical outcomes in patients with de novo 3-vessel disease (3VD) treated with contemporary PCI.BackgroundThe clinical impact of post-PCI QFR in patients treated with state-of-the-art PCI for de novo 3VD is undetermined.MethodsAll vessels treated in the SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery) II trial were retrospectively screened and analyzed for post-PCI QFR. The primary endpoint of this substudy was vessel-oriented composite endpoint (VOCE) at 2 years, defined as the composite of vessel-related cardiac death, vessel-related myocardial infarction, and target vessel revascularization. The receiver-operating characteristic curve was used to calculate the optimal cutoff value of post-PCI QFR for predicting 2-year VOCE. All the analyzable vessels were stratified on the basis of the optimal cutoff value.ResultsA total of 968 vessels treated with PCI were screened. Post-PCI QFR was analyzable in 771 (79.6%) vessels. A total of 52 (6.7%) VOCEs occurred at 2 years. The mean value of post-PCI QFR was 0.91 ± 0.07. The diagnostic performance of post-PCI QFR to predict 2-year VOCE was moderate (area under the curve: 0.702; 95% confidence interval: 0.633 to 0.772), with the optimal cutoff value of post-PCI QFR for predicting 2-year VOCE 0.91 (sensitivity 0.652, specificity 0.635). The incidence of 2-year VOCE in the vessels with post-PCI QFR <0.91 (n = 284) was significantly higher compared with vessels with post-PCI QFR ≥0.91 (n = 487) (12.0% vs. 3.7%; hazard ratio: 3.37; 95% confidence interval: 1.91 to 5.97; p < 0.001).ConclusionsA higher post-PCI QFR value is associated with improved vessel-related clinical outcomes in state-of-the art PCI practice for de novo 3VD. Achieving a post-PCI QFR value ≥0.91 in all treated vessels should be a target when treating de novo 3VD. These findings require confirmation in future prospective trials.  相似文献   
102.
In the Chx10-null ocular retardation (or(J)) mouse, retinal progenitor cell (RPC) proliferation is impaired, and bipolar neurons, a late born cell type, fail to differentiate. It is unclear whether Chx10 is required to maintain proliferation throughout retinogenesis or whether the bipolar cell defect is an indirect effect of growth arrest. We show that Chx10 is dispensable for late-stage RPC proliferation but is essential to promote bipolar cell genesis in place of rods. Ectopic Chx10 expression drove bipolar instead of rod cell differentiation without affecting division. Converting Chx10 to an activator impaired bipolar cell differentiation, implying that repression is important for Chx10 activity. In the Chx10 null or(J) retina, only a small fraction of cells expressing mutated Chx10 mRNA were rods, but this fraction increased after p27(Kip1) inactivation, which partially rescues proliferation. Most significantly, acute Chx10 knockdown in the postnatal retina promoted rods in place of bipolar neurons without affecting division. Thus, Chx10 directly controls bipolar cell genesis by inhibiting rod differentiation independent of its temporally limited early effect on RPC proliferation.  相似文献   
103.
Objective. The aim of this study was to evaluate the long‐term effects of stress on changes in health behaviour and cardiac risk profile in men and women. Design. A prospective cohort study. Setting. The Copenhagen City Heart Study, Denmark. Subjects. The analyses were based on 7066 women and men from the second (1981–1983) and third (1991–1993) wave of the Copenhagen City Heart Study. All participants were asked questions on stress and health behaviour and they had their weight, height, blood pressure and level of blood lipids measured by trained personnel. Main outcome measures. Changes in health behaviour (smoking, physical activity, alcohol consumption, overweight) and cardiac risk profile (cholesterol, HDL cholesterol, blood pressure, diabetes). Results. Individuals with high levels of stress compared to those with low levels of stress were less likely to quit smoking (OR = 0.58; 95% CI: 0.41–0.83), more likely to become physically inactive (1.90; 1.41–2.55), less likely to stop drinking above the sensible drinking limits (0.43; 0.24–0.79), and stressed women were more likely to become overweight (1.55; 1.12–2.15) during follow‐up. Men and women with high stress were more likely to use antihypertensive medication (1.94; 1.63–2.30), and stressed men were more than two times as likely to develop diabetes during follow‐up (2.36; 1.22–4.59). Conclusion. This longitudinal study supports a causal relation between stress and cardiovascular diseases mediated through unfavourable changes in health behaviour and cardiac risk profile.  相似文献   
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108.
Acute demyelinating optic neuritis   总被引:3,自引:0,他引:3  
Acute demyelinating optic neuritis associated with multiple sclerosis (MS) is the most common cause of inflammation of the optic nerve. The Optic Neuritis Treatment Trial (ONTT) has provided important clinical data on the use of corticosteroids, and demonstrated that patients with characteristic inflammatory lesions within the brain on magnetic resonance imaging had a greater chance of developing clinically definite MS (CDMS). The current approach to patients with optic neuritis has been modified by the results of the Controlled High-Risk Subjects Avonex Multiple Sclerosis Prevention Study (CHAMPS). Patients with an initial clinical episode of demyelination (optic neuritis, incomplete transverse myelitis, or brain-stem/cerebellar syndrome) and at least two characteristic demyelinating lesions within the brain were randomized to receive interferon beta-1a or placebo after initial treatment with intravenous corticosteroids. At the 3-year point patients treated with interferon beta-1a showed a 50% less risk of CDMS. The results of this study have set the standard for patients with a first bout of demyelinating optic neuritis.  相似文献   
109.
1. The maintenance of renal function in decompensated cirrhosis is highly dependent on prostaglandins (PGs). Since PG synthesis is mediated by cyclooxygenase-1 and -2 (COX-1 and COX-2), the present study was designed to examine which COX isoform is involved in this phenomenon. 2. Renal COX-1 and COX-2 protein expression and distribution were analysed by Western blot and immunohistochemistry in nine rats with carbon tetrachloride-induced cirrhosis and ascites and 10 control animals. The effects of placebo and selective COX-1 (SC-560) and COX-2 (celecoxib) inhibitors on urine flow (V), urinary excretion of sodium (U(Na)V) and PGE(2) (U(PGE2)V), glomerular filtration rate (GFR), renal plasma flow (RPF), the diuretic and natriuretic responses to furosemide and renal water metabolism were assessed in 88 rats with cirrhosis and ascites. 3. COX-1 protein levels were found to be unchanged in kidneys from cirrhotic rats. In contrast, these animals showed enhanced renal COX-2 protein expression which was focally increased in the corticomedullary region. Although U(PGE2)V was equally reduced by SC-560 and celecoxib, only SC-560 produced a significant decrease in U(Na)V, GFR and RPF and a pronounced impairment in the diuretic and natriuretic responses to furosemide in rats with cirrhosis and ascites. Neither SC-560 nor celecoxib affected renal water metabolism in cirrhotic rats. 4. These results indicate that despite abundant renal COX-2 protein expression, the maintenance of renal function in cirrhotic rats is mainly dependent on COX-1-derived prostaglandins.  相似文献   
110.
We examined the effects of chronic activity wheel running and antidepressant treatment on brain-derived neurotrophic factor (BDNF) messenger RNA (mRNA) in multiple brain regions-hippocampal formation (HF), ventral tegmental area/substantia nigra (VTA/SN), nucleus accumbens (NAc), and piriform cortex (PFx)-after bilateral olfactory bulbectomy (OBX). Male, Long-Evans rats (n=72) underwent either sham or OBX surgery and were randomly divided into eight experimental groups in a 2 (sham vs. OBX) x 2 (sedentary vs. activity wheel)x2 (saline vs. imipramine) factorial design. Animals were killed after 21 days of treatment. Drug x exercise interaction effects were observed for HF (P=0.006-0.023) and VTA/SN (P=0.021); exercise increased BDNF mRNA in the saline treated animals but not in the imipramine treated animals. OBX did not affect BDNF mRNA in the HF or VTA/SN (P>0.05). BDNF mRNA levels in the PFx were not altered by exercise, drug, or OBX (P>0.05). These results suggest that the effect of exercise on BDNF mRNA extends beyond the HF to the mesolimbic ventral tegmental area and that the potentiation of BDNF mRNA by exercise and antidepressant pharmacotherapy, reported by other investigators, is time limited.  相似文献   
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