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171.
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Background Amiodarone is a very effective antiarrhytmic drug. However its use may be accompanied by side effects. Hyperglobulinemia was not described in association with amiodarone treatment. Materials and methods Fifteen patients, who developed hyperglobulinemia while on amiodarone therapy, were identified among the patients hospitalized in our hospital. Serum globulin concentration was measured prior to, during and after amiodarone therapy. Results In 11 of the 15 patients with amiodarone-associated hyperglobulinemia, amiodarone treatment had to be stopped because of amiodarone-induced complications, nine of them had pneumonitis. Mean serum globulin level rose during amiodarone therapy from 2.48 ± 0.51 g/dL to 4.11 ± 0.71 g/dL (p = 0.001), and declined after it was stopped to 2.80 ± 0.49 g/dL (p = 0.001). In 50 patients treated by amiodarone, serum globulin was similar to that found in 50 patients with ischemic heart disease not treated by amiodarone [2.64 ± 0.39 g/dL and 2.56 ± 0.29 g/dL respectively (p = 0.21)]. Conclusions In some patients amiodarone therapy may be associated with hyperglobulinemia. The incidence of this association is not known. Most of the patients with amiodarone-associated hyperglobulinemia have amiodarone-induced toxicity, mainly pneumonitis. Amiodarone therapy does not cause a general increase in serum globulins. Hyperglobulinemia may be a marker for a damaged organ, or it may have a pathogenetic role in the induction of pneumonitis.  相似文献   
173.
Relationship between Helicobacter pylori CagA status and colorectal cancer   总被引:4,自引:0,他引:4  
OBJECTIVES: Infection with Helicobacter pylori, particularly with strains positive for CagA protein, increases the risk of gastric adenocarcinoma. Few studies have explored the possible association between H. pylori infection and colorectal cancer. This study evaluated whether the seroprevalence of CagA in H. pylori-infected patients affected risk for colorectal cancer independently of H. pylori status. METHODS: In this study, we tested serum IgG antibodies against H. pylori (ELISA) and CagA protein (Western blot assay) in 67 patients with colorectal adenocarcinoma, 36 with gastric adenocarcinoma, 47 with other malignancies (cancer controls), and 45 hospitalized for transesophageal echocardiography (TEE controls). Colonic cancer and gastric cancer patients with H. pylori infection were compared to each control group and to the pooled controls using simple and adjusted analyses. RESULTS: H. pylori infection was noted in 50 colon cancer patients, 31 gastric cancer patients, 31 cancer controls, and 32 TEE controls. In all, 41 (82%), 29 (94%), 11 (35%), and 13 (41%), respectively, of these H. pylori-positive sera expressed CagA reactivity (p < 0.001 for all pairwise comparisons between cases and controls). In the adjusted analysis, infection with H. pylori CagA+ compared to H. pylori CagA- was associated with increased risk for colorectal adenocarcinoma (odds ratio = 10.6; 95% CI = 2.7-41.3; p = 0.001) and gastric adenocarcinoma (odds ratio = 88.1; 95% CI = 6.3-1229.2; p = 0.001). CONCLUSIONS: Among patients infected with H. pylori, CagA+ seropositivity is associated with increased risk for both gastric and colonic cancer. This finding should stimulate additional research into the role of cagA+ H. pylori infection in the development of colorectal cancer.  相似文献   
174.
Mutations in cardiac troponin T (cTnT) are linked to a severe form of Familial Hypertrophic Cardiomyopathy. Patients carrying mutations flanking the tropomyosin-binding domain of cTnT (R92L and Delta160E) develop distinct clinical syndromes. In order to better understand the cellular pathophysiology underlying these clinically relevant differences, we studied isolated adult left ventricular myocytes from independent transgenic cTnT mouse lines carrying either a 35% (Delta160E) or 50% (R92L) replacement of the endogenous cTnT with the mutant forms. Measurement of baseline myocellular contraction revealed that the Delta160E cells had significant decreases in the peak rate of contraction and percent shortening as compared to either R92L or Non-TG myocytes. In addition, while both Delta160E and R92L myocytes demonstrated a decrease in the peak rate of relaxation as compared to Non-TG, the magnitude of the difference was significantly greater in Delta160E cells. Concurrent myocyte [Ca2+](i) transient measurements revealed that while the alterations in the peak rates and times of the rise and decline of the [Ca2+](i) transient were similar to the changes in the respective measures of sarcomeric mechanics, R92L cells also exhibited reduced rates of the rise and decline of the [Ca2+](i) transient but did not exhibit these reductions in terms of sarcomeric mechanics. Of note, only Delta160E, and not R92L myocytes, demonstrated significant reductions in SR Ca2+ load and uptake, corresponding to the impairments seen in the [Ca2+](i) and mechanical transients. Finally, Western analysis revealed a significant Delta160E-specific reduction in the SERCA2a/PLB ratio, which may well underlie the observed alterations in Ca2+ homeostasis. Therefore, independent cTnT mutations result in significant mutation-specific effects in Ca2+ handling that may, in part, contribute to the observed clinical variability in cTnT-related FHC.  相似文献   
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176.
We describe the prevalence of H. pylori and toxigenic Clostridium difficile (CD) infection and its relationship with gastrointestinal symptoms and pancreatic sufficiency (PS) or insufficiency (PI) in cystic fibrosis (CF) patients. Stool specimens from 30 consecutive patients with CF, aged 1–44, and from 30 healthy similarly aged subjects were tested for the H. pylori antigen by specific monoclonal antibodies and for CD toxins by Tox A/B assay and Tox A assay. CF patients were assessed clinically and tested for specific H. pylori serum antibodies and for mutations. In CF patients, the prevalence of H. pylori antigen was 16.6% (5/30), compared to 30% (9/30) in controls. Of the 26 CF patients with PI, only 2 (7.6%) were infected by H. pylori, compared with 3 of the 4 (75%) patients with PS (P=0.001). H. pylori infection was diagnosed in 3 of 5 (60%) CF patients carrying mild mutations, compared to 1 of 25 (4%) CF patients carrying severe mutations (P=0.01). Fourteen of 30 (46.6%) stool specimens from CF patients tested positive in the ToxA/B assay, and 3 of 14 tested positive for ToxA. No significant differences in antibiotic use, severity of lung disease, PI, chronic abdominal pain, or genotype were found between the two groups. None of the controls was positive for CD toxins. Prevalence of H. pylori infection in CF patients was lower than in similarly aged non-CF controls. CF patients with PI or a history of distal intestinal obstruction syndrome and those carrying mutations associated with a severe phenotype were protected against H. pylori infection. Almost half of the CF patients were asymptomatic carriers of CD producing mostly toxin B. More studies are needed to confirm our results in a larger group of CF patients.  相似文献   
177.
BACKGROUND: CD40 ligand (CD40L) is a trimeric, transmembrane protein of the tumor necrosis factor family and together with its receptor CD40 is an important contributor to the inflammatory processes that lead to atherosclerosis, plaque destabilization, and thrombosis. METHODS: In order to assess the association between serum concentrations of CD40 ligand (CD40L) and risk of future ischemic stroke and coronary events among patients with chronic CHD, we obtained baseline serum samples from patients (n = 3090) with chronic CHD enrolled in a secondary prevention trial. With a prospective nested case-control design, we measured baseline CD40L concentration in sera of patients who subsequently developed myocardial infarction, sudden cardiac death or ischemic stroke during follow-up (cases, n = 233) and in 233 age- and gender-matched pairs without any subsequent cardiovascular events. RESULTS: Relative odds for recurrent cardiovascular events per one natural log unit difference of CD40L were 0.97 (95%CI, 0.82-1.16). No increase in relative odds for recurrent cardiovascular events was observed per increasing quartiles of CD40L concentrations. In analysis for individual end-points, different trends of risks were observed beyond the 95 percentile for ischemic stroke (OR 2.22; 95%CI, 0.46-12.5) and for recurrent coronary events (OR 0.35; 95%CI, 0.07-1.37), but falling short of statistical significance. CONCLUSION: High serum concentrations of CD40L were not associated with increased risk of ischemic stroke or coronary events in patients with chronic coronary heart disease.  相似文献   
178.
Many sensory systems adapt their input-output relationship to changes in the statistics of the ambient stimulus. Such adaptive behavior has been measured in a motion detection sensitive neuron of the fly visual system, H1. The rapid adaptation of the velocity response gain has been interpreted as evidence of optimal matching of the H1 response to the dynamic range of the stimulus, thereby maximizing its information transmission. Here, we show that correlation-type motion detectors, which are commonly thought to underlie fly motion vision, intrinsically possess adaptive properties. Increasing the amplitude of the velocity fluctuations leads to a decrease of the effective gain and the time constant of the velocity response without any change in the parameters of these detectors. The seemingly complex property of this adaptation turns out to be a straightforward consequence of the multidimensionality of the stimulus and the nonlinear nature of the system.  相似文献   
179.
Older age is an independent predictor of mortality after percutaneous coronary intervention (PCI) in patients with Non-ST elevation Acute Coronary Syndrome (ACS). GPIIb/IIIa inhibitors are proved to improve outcome in high risk patients, but conflicting data are available about the effects of these inhibitors in elderly. Accordingly, we studied a consecutive population of elderly patients undergoing PCI for Non-ST elevation ACS. A total of 500 patients were divided in: GPI group (247 pts; mean age 77 ± 1.9 years) treated by stenting plus abciximab and, no GPI group (253 pts; mean age 77 ± 2.4 years) treated by stenting alone. Propensity analysis was used to account for the nonrandomized use of GPIIb/IIIa inhibitors. During hospitalization, incidence of death was similar among groups (3.2% vs 4.6%) without difference regarding incidence of major (1.6% vs 1.1%) and minor bleedings (4% vs 3%). At long-term follow-up the rate of death was significantly lower in GPI group (4.5% vs 12.3%; p = 0.002) as well as the rate of acute myocardial infarction (2.8% vs 11.1%; p = 0.0001), and pre-PCI (5.7% vs 13.4%; p = 0.003). Cox regression analysis identified abciximab use as an independent predictor of lower long-term major adverse cardiac event (MACE) after adjustment for propensity score (Exp (B) 0.620, 95%CI 0.394–0.976, p = 0.039). Our results suggest that addition of abciximab to stenting improves outcome in elderly patients with Non-ST elevation ACS, leading to an absolute benefit for reduction of death and MACE, with an acceptable rate of major and minor bleedings.  相似文献   
180.
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