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71.
BackgroundRisk stratification for ventricular arrhythmias (VA) and sudden death in nonischemic dilated cardiomyopathy (DCM) remains suboptimal.ObjectivesThe goal of this study was to provide an improved risk stratification algorithm for VA and sudden death in DCM.MethodsThis was a retrospective cohort study of consecutive patients with DCM who underwent cardiac magnetic resonance with late gadolinium enhancement (LGE) at 2 tertiary referral centers. The combined arrhythmic endpoint included appropriate implantable cardioverter-defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest, and sudden death.ResultsIn 1,165 patients with a median follow-up of 36 months, LGE was an independent and strong predictor of the arrhythmic endpoint (hazard ratio: 9.7; p < 0.001). This association was consistent across all strata of left ventricular ejection fraction (LVEF). Epicardial LGE, transmural LGE, and combined septal and free-wall LGE were all associated with heightened risk. A simple algorithm combining LGE and 3 LVEF strata (i.e., ≤20%, 21% to 35%, >35%) was significantly superior to LVEF with the 35% cutoff (Harrell’s C statistic: 0.8 vs. 0.69; area under the curve: 0.82 vs. 0.7; p < 0.001) and reclassified the arrhythmic risk of 34% of patients with DCM. LGE-negative patients with LVEF 21% to 35% had low risk (annual event rate 0.7%), whereas those with high-risk LGE distributions and LVEF >35% had significantly higher risk (annual event rate 3%; p = 0.007).ConclusionsIn a large cohort of patients with DCM, LGE was found to be a significant, consistent, and strong predictor of VA or sudden death. Specific high-risk LGE distributions were identified. A new clinical algorithm integrating LGE and LVEF significantly improved the risk stratification for VA and sudden death, with relevant implications for implantable cardioverter-defibrillator allocation.  相似文献   
72.
BackgroundCytotoxin-associated gene-A (CagA) antigen is expressed by some virulent strains of Helicobacter pylori (H. pylori). The role of CagA antigen in coronary instability is unknown. We performed a clinico-pathological study and a meta-analysis in the attempt to shed new light on this complex issue.MethodsIn the clinico-pathological study, 38 patients with unstable angina (UA), 25 patients with stable angina (SA), 21 patients with normal coronary arteries (NCA) and 50 age and sex matched healthy volunteers were enrolled. Serology for CagA was assessed in all patients. Specimens of atherosclerotic plaques were obtained from all patients by directional coronary atherectomy, and prepared for immunohistochemistry using anti-CagA monoclonal antibodies. The meta-analysis includes 9 studies assessing the association between seropositivity to CagA strains and acute coronary events.ResultsThe titre of anti-CagA antibodies was significantly higher in patients with unstable angina (161 ± 90 RU/ml) compared to those with stable angina (83 ± 59 RU/ml p < 0.02), NCA (47.3 ± 29 RU/ml p < 0.01) and healthy controls (73 ± 69 p < 0.02). Anti-CagA antibodies recognized antigens localized inside coronary atherosclerotic plaques in all specimens from both stable and unstable patients. In the meta-analysis, seropositivity to CagA was significantly associated with the occurrence of acute coronary events with an odds ratio (OR) of 1.34 (95% CI, 1.15–1.58, p = 0.0003).ConclusionsTaken together these findings suggest that in a subset of patients with unstable angina, an intense immune response against CagA-positive H. pylori strains might be critical to precipitate coronary instability mediated by antigen mimicry between CagA antigen and a protein contained in coronary atherosclerotic plaques.  相似文献   
73.
74.
This prospective randomized, double-blind, placebo-controlled, clinical trial was performed to evaluate the effectiveness of estrogens plus low-dose alendronate on bone metabolism. A total of 150 surgically postmenopausal women with osteoporosis were randomized in three groups: group A, micronized E2 (2 mg/d) plus standard-dose alendronate (10 mg/d); group B, micronized E2 plus low-dose alendronate (5 mg/d); and group C, micronized E2 plus placebo (one tablet per day). In all women, bone mineral density (BMD) and serum bone metabolism markers were assessed at admission and every 6 months for 2 yr. After 2 yr, BMD significantly increased compared with baseline in all groups. The percentage BMD change was significantly higher in groups A and B than in group C. The differences in BMD detected between groups A and B were not statistically significant. Since the 6-month follow-up and throughout the study, serum osteocalcin and bone alkaline phosphatase levels and urinary deoxypyridinoline and pyrilinks-D excretion were significantly reduced in all groups. Serum bone alkaline phosphatase levels significantly decreased in groups A and B, without difference between them, in comparison with group C. In conclusion, in surgically postmenopausal osteoporotic women treated with estrogen replacement, the addition of alendronate at a low dose of 5 mg daily induces a gain of bone mass not significantly different in comparison with that obtained using a standard dose of 10 mg daily.  相似文献   
75.
Increased cardiovascular morbidity and mortality were reported in GH deficiency (GHD), and GH replacement can ameliorate cardiac abnormalities of adult GHD patients. To test the potential progression of untreated GHD on the cardiovascular risk and cardiac function, cardiovascular risk factors, cardiac size, and performance were prospectively evaluated in 15 GHD patients (age, 18-56 yr) who were treated with recombinant GH at the dose of 0.15-1.0 mg/d, 15 GHD patients (age, 18-56 yr) who refused GH replacement, and 30 healthy subjects (age, 18-53 yr). Electrocardiogram, systolic and diastolic blood pressure, and heart rate measurement, serum IGF-I, total cholesterol, low- and high-density lipoprotein (LDL, HDL) cholesterol, triglycerides, and fibrinogen level assay, echocardiography, and equilibrium radionuclide angiography were performed basally and after 12 months. At study entry, low IGF-I levels, unfavorable lipid profile, and inadequate cardiac and physical performance were found in GHD patients compared with controls. After 12 months of GH treatment, IGF-I levels normalized; HDL-cholesterol levels, left ventricular (LV) mass index (LVMi), left ventricular ejection fraction (LVEF) at peak exercise, peak filling rate, exercise duration and capacity significantly increased; total- and LDL-cholesterol levels significantly decreased. After 12 months in GH-untreated GHD patients, IGF-I levels remained stable, and HDL-cholesterol levels, LVEF both at rest and at peak exercise, and exercise capacity were further reduced; total- and LDL-cholesterol levels increased slightly. LVEF at rest and its response at peak exercise normalized in 60 and 53.3%, respectively, of GH-treated patients and in none of the GH-untreated patients. In conclusion, 12 months of GH replacement normalized IGF-I and improved lipid profile and cardiac performance in adult GHD patients. A similar period of GH deprivation induced a further impairment of lipid profile and cardiac performance. This finding strongly supports the need of GH replacement in adult GHD patients.  相似文献   
76.
OBJECTIVE: To evaluate endothelial function in type 2 diabetic patients with and without diabetic nephropathy. METHODS: We studied the effects of systemic infusion of the nitric oxide (NO) synthase inhibitor NG-monomethyl-l-arginine (L-NMMA) on cardiovascular and renal hemodynamics in six type 2 diabetic patients with microalbuminuria (D2-MA), six type 2 diabetic patients with normoalbuminuria (D2-NA) and five control subjects. Both type 2 diabetic patients and control subjects had mild arterial hypertension. RESULTS: L-NMMA infusion decreased the cardiac index in all groups. A reduction in glomerular filtration rate (GFR) and an increase in filtration fraction were observed only in controls. Renal plasma flow decreased in controls and D2-NA patients and renal vascular resistance increased in all groups. CONCLUSIONS: The effect of L-NMMA on cardiac output was similar in controls and type 2 diabetic patients with and without diabetic nephropathy. In contrast, the effect on GFR was impaired in both diabetic groups, suggesting that glomerular NO homeostasis is altered in type 2 diabetes. Moreover the discrepancy, in diabetic patients, between cardiac and renal effects during L-NMMA infusion suggests that the modulation of glomerular hemodynamics is independent from NO-regulated cardiac output.  相似文献   
77.
The aim of GH replacement therapy in GH-deficient adults is to optimize response with minimum incidence of adverse reactions, but optimal therapy regimens are still to be established. This two-arm parallel study examined effects of two GH dose algorithms in adults with GH deficiency of adult or childhood onset. Patients on low dose (LD; n = 302) received GH at 3 microg/kg per day for 3 months increasing to 6 microg/kg per day for 3 months, and those on conventional dose (CD; n = 293) started on 6 microg/kg per day for 3 months increasing to 12 microg/kg per day for 3 months. The proportion of patients completing therapy was greater for the LD group than the CD group for the first 3 months (93.0% vs. 88.1%; P = 0.037) and overall for the 6 months (90.7% vs. 84.0%; P = 0.013). Both dose groups showed significant increases in lean body mass and decreases in fat mass for all time points. Percent increase in lean body mass was less with LD than CD over the first 3 months (2.43 +/- 4.33 vs. 3.58 +/- 4.69%; P = 0.006) but not overall for the 6-month period (4.38% +/- 5.34% vs. 5.21% +/- 5.99%; P = 0.141). Percent decrease in fat mass was less with LD than CD for the first 3 months (-2.81% +/- 7.81% vs. -5.53% +/- 8.64%; P < 0.001) and overall for the 6-month period (-6.35% +/- 9.42% vs. -9.45% +/- 12.07%; P = 0.006). IGF-I SD score increased less with LD than CD for 0 to 3 and 0 to 6 months, although for IGF-binding protein-3 SD score, there was no significant difference between doses at any time. Arthralgia was the only adverse event that occurred significantly less frequently with LD than with CD. Calculated changes based on gender and onset indicated greater changes in males than females for body composition, but there was little difference in GH-related adverse events between males and females. The lower starting dose with dose titration appeared more favorable, but differences in response between genders and onset of GH deficiency need to be taken into account when setting an individual dose regimen.  相似文献   
78.
Alveolar macrophages (AMs) are the predominant defense cells in the airway, and their numbers are increased in smokers and subjects with chronic obstructive pulmonary disease. This increase may result from increased recruitment, increased proliferation, or reduced cell death. Apoptosis regulates inflammatory cell survival, and p21(CIP1/WAF1) is an important inhibitory regulator of cycle progression after oxidative stress. We have investigated whether chronic smoke exposure influences the expression and localization of cell cycle and apoptotic proteins in AM and bronchial epithelial cells in vivo. The increased numbers of AMs seen in smokers were only partially due to enhanced proliferation. p21(CIP1/WAF1) protein expression was increased in AMs and biopsies isolated from smokers and was found predominantly within the cytoplasm. In addition, B cell lymphoma leukemia (Bcl)-x(L), an antiapoptotic regulator, was also highly expressed in macrophages from smokers compared with nonsmokers and subjects with asthma. Hydrogen peroxide, an oxidative stress, induced cytoplasmic expression of p21(CIP1/WAF1) and failed to induce apoptosis in an in vitro model. These results suggested that AM and bronchial epithelial cells from smokers, in contrast to those from normal subjects and subjects with asthma, have reduced cell death. Thus, oxidative stress induced by cigarette smoking may contribute to the chronicity of inflammation in the airway, through a reduction of apoptosis.  相似文献   
79.
Effects of carbonated water on functional dyspepsia and constipation   总被引:4,自引:0,他引:4  
OBJECTIVE: The effects of carbonated beverages on the gastrointestinal tract have been poorly investigated. Therefore, this study aims to assess the effect of carbonated water intake in patients with functional dyspepsia and constipation. METHODS: Twenty-one patients with dyspepsia and secondary constipation were randomized into two groups in a double-blind fashion. One group (10 subjects) drank carbonated water and the other (11 subjects) tap water for almost 15 days. Patients were evaluated for dyspepsia and constipation scores, and underwent a satiety test by a liquid meal, radionuclide gastric emptying, sonographic gallbladder emptying and colonic transit time, using radio-opaque markers. RESULTS: The dyspepsia score was significantly reduced with carbonated water (before = 7.9 +/- 2.8 after = 5.4 +/- 1.7; 0.05) and remained unmodified after tap water (9.7 +/- 5.3 9.9 +/- 4.0). The constipation score also decreased significantly ( 0.05) after carbonated water (16.0 +/- 3.9 12.1 +/- 4.4; 0.05) and was not significantly different with tap water (14.7 +/- 5.1 13.7 +/- 4.7). Satiety was significantly reduced with carbonated water (before = 447 +/- 146 kcal after = 590 +/- 245; 0.01). Gallbladder emptying (delta percent contraction) was significantly improved only with carbonated water (39.9 +/- 16.1% 53.6 +/- 16.7%; 0.01). CONCLUSION: In patients complaining of functional dyspepsia and constipation, carbonated water decreases satiety and improves dyspepsia, constipation and gallbladder emptying.  相似文献   
80.
Pentraxin-3 (PTX3), an acute-phase protein that belongs to the family of the PTXs, is found elevated in septic shock and increased in patients with acute myocardial infarction. As tissue factor (TF) plays a key role in thrombosis and inflammation associated with atherosclerosis and as we have recently reported that PTX3 increases TF synthesis in endothelial cells, we tested whether PTX3 could modulate TF expression in monocytes. Monocytes from peripheral blood of healthy donors were incubated with highly purified PTX3 with or without lipopolysaccharide (LPS). Cells were then disrupted, and procoagulant activity was assessed by a one-stage clotting time. PTX3 enhanced TF activity and antigen from LPS-stimulated monocytes in a dose-dependent way. The effect was specific, as other PTXs, such as C-reactive protein and serum amyloid P component, were ineffective. Moreover, the increase in activity was specific for LPS, as in the presence of other TF-inducing agents such as interleukin-1beta and tumor necrosis factor alpha, PTX3 was not effective. The increase in TF activity requires mRNA synthesis, as assessed by polymerase chain reaction. The mechanism by which PTX3 modulates TF synthesis resides in an enhanced IkappaB, alpha phosphorylation and degradation and increased migration of the transacting factor c-Rel/p65 into the nucleus, as determined by Western blot and electro-mobility shift assay. These results show that PTX3 is an enhancer of the expression of TF by mononuclear cells. In the area of vascular injury, during the inflammatory response, cell-mediated fibrin deposition takes place. PTX3 increases TF expression, thus potentially playing a role in thrombogenesis and wound healing.  相似文献   
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