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71.
Aim: To determine the influence of smoking on the blood and salivary superoxide dismutase levels among smokers, and to demonstrate the significance in alterations in the levels of superoxide dismutase in association with patient age, periodontal disease status, and duration and smoking frequency. Methods: Sixty healthy male patients (aged 20–60 years) constituted the target population. Blood and saliva samples were collected, and the periodontal index was measured using a Community Periodontal Index probe. Blood and salivary superoxide dismutase levels were calculated with the reagents prepared, and values were measured in a UV spectrophotometer. Results: There was a significant decrease in mean superoxide dismutase levels with an increase in age and smoking duration and frequency (0.23–0.05 U/mL). There was a range of 0.31–0.06 U/mL variation in the mean superoxide dismutase levels as the periodontal disease condition deteriorated. Conclusions: There was a significant reduction in the superoxide dismutase levels in the blood and saliva of smokers with increased duration and frequency of smoking, and as the periodontal disease condition worsened. Thus, this study emphasizes the importance of saliva as an easy, non‐invasive procedure in the diagnosis of patients who are more prone to precancerous lesions and conditions, and its importance in patient education and motivation programs for smoking cessation.  相似文献   
72.
Sprouty proteins are established modifiers of receptor tyrosine kinase (RTK) signaling and play important roles in vasculogenesis, bone morphogenesis, and renal uteric branching. Little is understood, however, concerning possible roles for these molecular adaptors during hematopoiesis. Within erythroid lineage, Spry1 was observed to be selectively and highly expressed at CFU-e to erythroblast stages. In analyses of possible functional roles, an Mx1-Cre approach was applied to conditionally delete Spry1. At steady state, Spry1 deletion selectively perturbed erythroid development and led to reticulocytosis plus heightened splenic erythropoiesis. When challenged by hemolysis, Spry1-null mice exhibited worsened anemia and delayed recovery. During short-term marrow transplantation, Spry1-null donor marrow also failed to efficiently rescue the erythron. In each anemia model, however, hyperexpansion of erythroid progenitors was observed. Spry function depends on phosphorylation of a conserved N-terminal PY motif. Through an LC-MS/MS approach, Spry1 was discovered to be regulated via the erythropoietin receptor (EPOR), with marked EPO-induced Spry1-PY53 phosphorylation observed. When EPOR signaling pathways were analyzed within Spry1-deficient erythroid progenitors, hyperactivation of not only Erk1,2 but also Jak2 was observed. Studies implicate Spry1 as a novel regulator of erythropoiesis during anemia, transducer of EPOR signals, and candidate suppressor of Jak2 activity.  相似文献   
73.
Plasma cell myeloma (PCM) is a lymphoproliferative disorder characterized by the malignant growth of monoclonal plasma cells within the bone marrow. Although risk factors for the development of PCM have been identified, the etiology on the majority of patients with PCM remains unclear. Cigarette smoking has been postulated as a potential risk factor for lymphoid malignancies; however, the association with PCM is inconclusive. We have carried out a meta-analysis of observational studies to assess the relationship, if any, between cigarette smoking and PCM. A literature search through December 2011 rendered 4 prospective cohort and 13 case–control studies evaluating such association. Our categorical meta-analysis showed that there is no association between ever, current, and former smokers and PCM.This lack of association was maintained when analyzing by study design, study quality, and geographical area of report. Similarly, meta regression analysis showed no association with the number of cigarettes smoked per day. In conclusion, our meta-analysis shows that there is no relationship between cigarette smoking and an increased incidence of PCM. Future studies should focus on other potential risk factors for PCM.  相似文献   
74.
The objective of this study is to evaluate clinical picture, radiological findings and response to treatment in patients with antibiotic associated status epilepticus (SE). In a retrospective review, 12 out of 117 (10%) patients with SE had temporal association with antibiotic administration. Their medical history, clinical findings, and duration and type of SE were recorded. Serum chemistry, blood counts, cranial MRI, EEG and CSF examination were carried out. The offending antibiotics were withdrawn and the patients were treated with phenytoin, lorazepam, sodium valproate or midazolam. The response to treatment was recorded and death during hospital stay noted. The median age of the patients was 36 (18 and 74) years and 5 were females. Eight patients had convulsive and four nonconvulsive SE. The median duration of status was 12 h. The antibiotics related to SE included intravenous cephalosporin (ceftazidime 5, amoxyclavulenic acid 2, piperacillin 2, cefepime 1) and quinolones (levofloxacin 3, ofloxacin 1, ciprofloxacin 2) in isolation or in combinations. Five patients had hepatic (41.7%) and 6 (50%) renal failure; the later received higher than the recommended dose of antibiotics. Cranial MRI was abnormal in 7 out of 9 (77.8%) patients that include cortical lesion in one, corticosubcortical in three and subcortical in three. SE responded to first antiepileptic drug in four and to second in five patients. Three patients (25%) had refractory SE. Eight (66.7%) patients died and death was related to SE in 2 patients. 10% SE patients may be related to antibiotics. Hence the antibiotic should be carefully chosen in patients with hepatic and renal failure, and the dose should be modified.  相似文献   
75.
Lipoleiomyomas are benign mesenchymal tumours of smooth muscle and adipose tissue and uncommonly occur in the uterus. Here we report a case of uterine lipoleiomyoma that manifested purely as intravenous component and clinically presented as a large retroperitoneal mass with extension into inferior vena cava and right atrium. The connection of the mass to the corneal end of the uterus was noted only at surgery.  相似文献   
76.
Background: Atorvastatin (ATV) is a specific competitive inhibitor of 3‐hydroxy‐2‐methyl‐glutaryl coenzyme A reductase. Recently, statins have shown pleiotropic effects such as anti‐inflammation and bone stimulation. The aim of the present study is to investigate the effectiveness of 1.2% ATV as an adjunct to scaling and root planing (SRP) in the treatment of intrabony defects (IBDs). Methods: Sixty individuals were randomized into two treatment groups: SRP plus 1.2% ATV and SRP plus placebo gel. At baseline and 3, 6, and 9 months, clinical parameters, which included modified sulcus bleeding index, plaque index, probing depth (PD), and clinical attachment level (CAL), were recorded at baseline. Radiologic assessment of IBD fill was done using computer‐aided software at baseline and 6 and 9 months. Results: Mean PD reduction and mean CAL gain were greater in the ATV group than the placebo group at 3, 6, and 9 months. A significantly greater mean percentage of radiographic bone fill was found in the ATV group (35.49% ± 5.50%) compared to the placebo group (1.82% ± 1.32%) after 9 months. Conclusion: ATV as an adjunct to SRP can provide a new direction in the management of IBDs.  相似文献   
77.
Background: Metformin (MF) (1,1‐dimethylbiguanide HCl) is one of the most commonly used oral antihyperglycemic agents for the treatment of type 2 diabetes mellitus. Recently, MF has been shown to have bone‐sparing properties. The present study is designed to investigate the effectiveness of MF 1% in an indigenously prepared, biodegradable, controlled‐release gel, as an adjunct to scaling and root planing (SRP) in treatment of vertical defects in smokers with generalized chronic periodontitis (CP). Methods: Fifty patients were categorized into two treatment groups: SRP plus 1% MF and SRP plus placebo. Clinical parameters were recorded at baseline and at 3 and 6 months; they included plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), and clinical attachment level (CAL). At baseline and after 6 months, intrabony defect (IBD) fill was radiologically assessed using computer software. Results: Mean PD reduction and mean CAL gain were found to be greater in the MF group than the placebo group at all visits. Furthermore, a significantly greater mean percentage of bone fill was found in the MF group (26.17% ± 6.66%) than the placebo sites (3.75% ± 8.06%) (P <0.001). Conclusion: There was greater decrease in mSBI and PD and more CAL gain with significant IBD fill at vertical defect sites treated with SRP plus locally delivered MF, versus SRP plus placebo, in smokers with generalized CP.  相似文献   
78.
Background: Simvastatin (SMV) is a specific competitive inhibitor of 3‐hydroxy‐2‐methyl‐glutaryl coenzyme A reductase. Recently, it has been reported that statins promote bone formation. The present study is designed to investigate the effectiveness of 1.2% SMV in an indigenously prepared, biodegradable, controlled‐release gel as an adjunct to scaling and root planing (SRP) in the treatment of patients with type 2 diabetes and chronic periodontitis (CP). Methods: Thirty‐eight patients were categorized into two treatment groups: SRP plus 1.2% SMV and SRP plus placebo. Clinical parameters were recorded at baseline before SRP and at 3, 6, and 9 months; they included modified sulcus bleeding index (mSBI), probing depth (PD), and clinical attachment level (CAL). At baseline and after 6 and 9 months, radiologic assessment of intrabony defect (IBD) fill was done using computer‐aided software. Results: Mean PD reduction and mean CAL gain were found to be greater in the SMV group than the placebo group at 3, 6, and 9 months. Furthermore, significantly greater mean percentage of bone fill was found in the SMV group (32.64% ± 12.90%) compared to the placebo group (4.22% ± 9.75%) after 9 months. Conclusion: There was a greater decrease in mSBI and PD and more CAL gain with significant IBD fill at sites treated with SRP plus locally delivered SMV in patients with type 2 diabetes and CP.  相似文献   
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