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11.

Objective

To investigate the effect of a resin infiltrant on the surface microhardness and roughness of healthy enamel and, as a subsidiary aim, to compare it with a fissure sealant.

Materials and methods

Twenty freshly extracted premolars were used. Sound enamel surfaces were treated with a resin infiltrant (Icon) or fissure sealant (Seal-Rite). The average roughness (Ra, μm) of the specimens was measured with a profilometer (Surtronic 10 Tylor Hobson). Surface hardness was determined by utilizing Vicker’s surface hardness (VHN) with a Micromet II Microhardness tester. Each specimen acted as its own control. Data were analyzed with 2-way analysis of variance (ANOVA), and mean values were compared with independent t-test. All analyses were performed with the SPSS program version 16 (USA). Differences with a P-value of ⩽0.05 were considered statistically significant.

Results

Comparison of enamel surfaces before and after application of resin infiltrant revealed no significant differences in surface hardness; however, enamel surfaces treated by infiltrant showed significantly higher VHN (244.0 ± 79.8) values than those treated with fissure sealant (37.5 ± 14.2). Surface roughness did not differ before and after application of either material to sound enamel. Enamel surfaces treated with fissure sealant (5.3 ± 1.4) were significantly smoother than those treated with infiltrant (6.9 ± 2.0).

Conclusion

Within the limitations of the study, the results showed that enamels treated with the resin infiltrant showed approximately the same microhardness and surface roughness as sound enamel, indicating that this material might be suitable for the treatment of enamel subsurface lesions.  相似文献   
12.
Artemisia campestris L. has been widely used in alternative medicine to treat digestive system diseases, particularly gastroesophageal disorders. In the present investigation, we studied the putative protective effect of Artemisia campestris aqueous extract (ACAE) against gastro-esophageal reflux (GER)-induced esophagitis in rats. The experimental ophagitis was induced by the ligation of the pylorus as well as the junction between the forestomach and the corpus. We firstly found that ACAE administration at 100, 200 and 400?mg/kg, b.w., p.o. significantly protected GER-induced macroscopic and histological injuries in the esophagus tissue. Our extract also counteracted GER-induced esophagus lipoperoxidation, restored the depletion of antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) as well as thiol groups levels. Furthermore, we showed that acute GER provoked an increase in esophagus mucosa hydrogen peroxide (H2O2), free iron and calcium levels, whereas ACAE treatment reversed all GER-induced intracellular mediators’ disturbances. In conclusion, we suggested that ACAE had potent protective effects against esophagitis due, in part, to its antioxidant properties as well as its opposite effect on some intracellular mediators.  相似文献   
13.
14.
The role and effect of preserved antegrade pulmonary blood flow (APBF) at the time of bidirectional cavopulmonary anastomosis (BCPA) in the management of single-ventricle physiology is controversial. We investigated the influence of APBF on the fluid dynamics of BCPA connection using computational fluid dynamics (CFD). Patient-specific, three-dimensional geometry of a BCPA connection with native pulmonary artery (PA) trunk was reconstructed and transient CFD simulations were done at four predetermined mean flow rates of PA trunk (0.5L/min, 1L/min, 1.5L/min and 2L/min). During a cardiac cycle, the flow ratio of left pulmonary artery (LPA)/right pulmonary artery (RPA) increased from 1.91 to 2.50, and average control volume power loss increased from 0.76 mW to 18.05 mW when the mean flow rate of PA trunk changed from 0.5L/min to 2L/min. The pulsatility of pressures in LPA, RPA and superior vena cava became more prominent as the amount of APBF increased. Local fluid structures in the connection area at four levels of APBF differed from each other.  相似文献   
15.
Mutations of OCRL1 are associated with both the Lowe oculocerebrorenal syndrome, a multisystemic and Dent-2 disease, a renal tubulopathy. We have identified a mutation in 130 Lowe syndrome families and 6 affected by Dent-2 disease with 51 of these mutations being novel. No founding effect was evidenced for recurrent mutations. Two mutations initially reported as causing Dent-2 disease were identified in patients, including two brothers, presenting with Lowe syndrome thus extending the clinical variability of OCRL1 mutations. mRNA levels, protein content, and PiP(2) -ase activities were analyzed in patient's fibroblasts. Although mRNA levels were normal in cells harboring a missense mutation, the OCRL1 content was markedly lowered, suggesting that enzymatic deficiency resulted mainly from protein degradation rather than from a catalytic inactivation. Analysis of a splicing mutation that led to the elimination of the initiation codon evidenced the presence of shortened forms of OCRL1 that might result from the use of alternative initiation codons. The specific mapping of the frameshift and nonsense mutations, exclusively identified in exons 1-7 and exons 8-23, respectively, for Dent disease and Lowe syndrome together with the possible use of alternative initiation codons might be related to their clinical expression, that is, Lowe syndrome or Dent-2 disease.  相似文献   
16.
精制Vero细胞狂犬病疫苗的临床观察及免疫学效果 …   总被引:8,自引:0,他引:8  
目的 目前我国使用的人用狂犬病疫苗生产工艺较落后,致使用后副反应较严重,而国际上Vero细胞狂犬病疫苗已研制成功和使用近20年,不仅免疫效果良好而且副反应很轻。为了改变我国狂犬病疫苗生产工艺的落后和质量较差的状况,而开展此项研究。方法 海南省生物制品研究所和河南省生物技术研究所联合研制的Vero细胞狂犬病疫苗获得卫生部批准进行临床观察,该疫苗以aG株适应Vero细胞后为生产毒种,转瓶培养、并浓缩适  相似文献   
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18.
Objectives:To explore the influence of epilepsy on quality of life (QoL) among people with epilepsy in Saudi Arabia, and its association with sociodemographic and clinical characteristic aspects in the Qassim region.Methods:A cross-sectional multi-centered study done in the Qassim region from June 2018 to May 2019. A self-administered questionnaire was provided to 216 participants who attended the neurology clinic. We used a validated Arabic version of the QoL in Epilepsy (QOLIE-31) to measure the QoL.Results:The mean of the overall QOLIE-31 score was 64.23 ± 17.8. we found that employment status had a significant influence on the overall score (p<0.001) and all other QOL domains (rho ranged from -.136 for energy fatigue to -.193 for social function) Patients with focal seizures were significantly higher in emotional wellbeing (rho=-.159), seizure worry (rho=-.226), cognitive function (rho=-.166) and overall score (p=0.010) than patients with the generalized type. Monotherapy patients have higher scores in total (p<0.001) and all subscales except seizure worry and emotional wellbeing than those on polytherapy.Conclusion:Employment status, type of seizure, and AED number are the most important factors affecting Saudi patient’s QoL.

Many studies in multiple countries have tested quality of life (QoL) in epilepsy, and have highlighted areas of common concern. It has been shown that among Arabian people, epileptic patients are generally more susceptible to having higher levels of anxiety and depression.1 In Kenya, researchers have compared QoL between persons with epilepsy (PWE) and healthy people who have the same environment, social relationship, and living circumstances. These authors found that low education level, unemployment rate, unskilled employment, and low income were higher in PWE compared to their non-epileptic accompanying people.2 Despite the high prevalence rate in Saudi Arabia (6.54 per 1000),3 there has been limited research about the impact of QoL in epileptic patients. To better identify the factors that influence Saudi epilepsy patients, here we explore the influence of epilepsy on QoL among Saudi epileptic patients.  相似文献   
19.
Objectives:To review the experience of 2 tertiary centers in Saudi Arabia with intracranial hypertension (IH) in the pediatric population.Methods:We retrospectively reviewed and analyzed pediatric patients diagnosed with IH from June 2002 to May 2017 in 2 institutes.Results:We identified 53 patients (30 females and 23 males) with a mean age of 7 years at the time of presentation. Among them, 41 patients were younger than 12 years, and 12 were older. Obese and overweight patients constituted 27.00% (n = 14) of all cases, 8 (66.7%) of whom were older than 12 years. The most common presenting feature was papilledema followed by headache. Vitamin D deficiency, which constituted the most common associated condition, was identified in 12 (22.6%) patients. Acetazolamide was the treatment option in 98.11% of patients, and only 5.7% underwent surgical interventions. The length of follow-up ranged from 6 months to 8 years.Conclusion:Intracranial hypertension is rare in children and commonly seen in overweight females older than 12 years similar to adults. Patients younger than 12 years tend to develop secondary IH. More studies are needed to characterize the clinical presentation and guide the management plan.

Intracranial hypertension (IH) is rarely reported in children. It is characterized by increased intracranial pressure (ICP) without any evidence of underlying brain pathology, structural abnormalities, hydrocephalus, or any abnormal meningeal enhancement.1 The incidence of IH differs from region to region due to variations in the prevalence of obesity and other secondary causes. The annual incidence of IH in children is 0.9 per 100,000 in the United States,2 0.5 per 100,000 in Germany,3 0.6 per 100,000 in Nova Scotia and Prince Edward Island in Eastern Canada,4 and 1.2 per 100,000 in Croatia.5 A study carried out in Oman estimated the incidence of IH to be 1.9 per 100,000 in children below 15 years of age; with it being higher in female children.6 The present study aimed to review the clinical presentation, possible aetiological factors, diagnosis, management, and outcomes in children with IH in 2 tertiary institutes in Saudi Arabia.  相似文献   
20.
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