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21.
Objective To determine the incidence of cardiac tamponade related to peripherally inserted central catheters in newborns weighing less than 1,500 g during the past 8 years and to provide guidelines in order to avoid death due to this complication.Design Retrospective case review.Setting Tertiary level neonatal intensive care unit.Patients and participants Retrospective study of a total of 280 peripherally inserted central catheters positioned in 258 preterm newborns.Measurements and results Five cardiac tamponades were observed, giving an incidence of 1.8%. Data from our cases included clinical presentation and outcome, biochemical evaluation of pericardial fluid, days until diagnosis, central catheters characteristics, insertion site and tip placement site.Intervention Two of the infants did not respond to resuscitation measures including cardiac massage and the administration of epinephrine. Post-mortem examination revealed the intrapericardial accumulation of protein and lipid alimentation solution. The other three patients were successfully resuscitated by timely pericardiocentesis. All five infants had routinely performed serial radiographs and cardiac color Doppler ultrasonography that showed correct catheter tip placement.Conclusions The incidence of cardiac tamponade could be reduced by following specific guidelines. The possibility of tamponade must be kept in mind during the resuscitation of any preterm infant with a peripherally inserted central catheter in place who develops symptoms of shock or sudden bradycardia. Our experience shows that even preterm infants with cardiac tamponade can be successfully resuscitated by timely pericardiocentesis in most cases.  相似文献   
22.

Objectives

The purpose of this study was to evaluate the in vitro effectiveness of a new bioglass-containing and two commercial desensitising toothpastes on dentinal tubule occlusion after citric acid challenge or artificial saliva (AS) immersion.

Methods

One hundred dentin discs from human third molars were used. Specimens were randomly divided into five groups (n = 20), Group 1: EDTA-treated dentin; Group 2: brushing with distilled water; Group 3: brushing with Novamin; Group 4: brushing with Sensodyne Freshmint; Group 5: brushing with Colgate Sensitive. In each group, samples were then equally split into two subgroups (n = 10) to test two post-treatments: 6% citric acid challenge or 24 h immersion in artificial saliva. Dentine permeability of each specimen was measured before and after each treatment using a hydrostatic device working at 20 cm H2O pressure. Data were analysed by two-way repeated measures ANOVA to determine if there were any significant differences within or between groups. Dentine morphology and surface deposits were observed by SEM.

Results

All three desensitising toothpastes significantly reduced dentine permeability and created precipitates on the treated dentine surfaces. Moreover, the reductions in dentine permeability showed partial recovery after a citric acid and artificial saliva immersion. Sensodyne showed significant resistant to acid attack and Novamin exhibited the lowest permeability after artificial saliva immersion for 24 h.

Conclusions

The application of the three toothpastes resulted in effective dentinal tubule occlusion. However, the new bioglass-containing toothpaste (Novamin) represented excellent occlusion effects after brushing treatment and AS immersion, while Sensodyne demonstrated more reduction in permeability when citric acid challenged.  相似文献   
23.

Objectives

The exposure of dentinal tubules causes fluid movement and dentinal hypersensitivity. This study aimed at evaluating the dentine permeability after prophylactic measures performed on exposed dentine after immersion in artificial saliva and citric acid challenge. Confocal microscopy was performed to evaluate the percentage of occluded tubules (OCT%) and the changes in dentine morphology.

Methods

Prophy-powders and pastes were tested in this study. An oxalic acid liner was used as a positive control. Dentine discs from human third molars were treated with each material and the dentine permeability was evaluated using a fluid filtration system working at 20 cm H2O. Artificial saliva and citric acid were used for the determination of changes in dentine permeability. The percentage of tubule occlusion capability (OCT%) was evaluated using confocal microscopy.

Results

All the products used in this study were able to significantly reduce the dentine permeability of acid-etched specimens. The use of the bioactive glass and sodium bicarbonate showed the highest values in dentine permeability reduction. However, the air-polishing procedures performed with Sylc bioactive glass powder created a dentine surface resistant to citric acid attack.

Conclusion

Bioactive glass is suitable for treatment of dentinal hypersensitivity by creating a dentine surface resistant to citric acid attack.  相似文献   
24.
The etiopathogenesis of eating disorders (ED) is complex and poorly understood. Biological, psychological and environmental factors have all been considered to be involved in the onset and the persistence of these syndromes, often with conflicting results. The recent literature focused on the possible role of hormonal pathways, in particular the hypothalamic-pituitary-adrenal (HPA) axis, as a relevant factor capable of influencing the onset and the course of ED. Other studies have suggested that the onset of ED is often preceded by severe life events, and that chronic stress is associated with the persistence of these disorders. As the biological response to stress is the activation of the HPA axis, the available literature considering the relationships between stress, HPA axis functioning and anorexia nervosa, bulimia nervosa and binge eating disorder is reviewed by the present article.  相似文献   
25.
The purpose of this study was to evaluate the influence of the oxidized surface on bone-to-implant contact (BIC%), the bone density in the threaded area (BA%), as well as the bone density outside the threaded area (BD%) in human jaws after 2 months of unloaded healing. Thirteen subjects (mean age 42.61 +/- 6.15 years) received two microimplants (2.5 mm diameter and 6 mm length) each, during conventional mandible or maxilla implant surgery. The microimplants with commercially pure titanium surfaces (machined) and oxidized surfaces served as the control and test surfaces, respectively. After 2 months, the microimplants and the surrounding tissue were removed and prepared for histomorphometric analysis. All microimplants, except two machined and one oxidized microimplant surfaces, were found to be clinically stable after the healing period. Histometric evaluation indicated that the mean BIC% was (21.71 +/- 13.11)% and (39.04 +/- 15.75)% for machined and oxidized microimplant surfaces, respectively. The BD% was higher for the oxidized surface, although there was no difference for maxilla and mandible. The oxidized surface impacted the BA% for the type-IV bone. Data suggest that the oxidized surface presented a higher bone-to-implant contact rate compared with machined surfaces under unloaded conditions, after a healing period of 2 months.  相似文献   
26.
Clinical practice guidelines (CPGs) contain evidence‐based recommendations to guide clinical care, policy development, and quality of care improvement. A recent systematic review of epilepsy guidelines identified considerable variability in the quality of available guidelines. Although excellent frameworks for CPG development exist, processes are not followed uniformly internationally, and resources to develop CPGs may be limited in certain settings. An International League Against Epilepsy (ILAE) working group was charged with proposing methodology to guide the development of future epilepsy‐specific CPGs. A comprehensive literature search (1985–2014) identified articles related to CPG development and handbooks. Guideline handbooks were included if they were publicly available, and if their methodology had been used to develop CPGs. The working group's expertise also informed the creation of methodologies and processes to develop future CPGs for the ILAE. Five handbooks from North America (American Academy of Neurology), Europe (Scottish Intercollegiate Guidelines Network & National Institute for Health and Care Excellence), Australia (National Health and Medical Research Council), World Health Organization (WHO), and additional references were identified to produce evidence‐based, consensus‐driven methodology for development of epilepsy‐specific CPGs. Key components of CPG development include the following: identifying the topic and defining the scope; establishing a working group; identifying and evaluating the evidence; formulating recommendations and determining strength of recommendations; obtaining peer reviews; dissemination, implementation, and auditing; and updating and retiring the CPG. A practical handbook and toolkit was developed. The resulting CPG development toolkit should facilitate the development of high‐quality ILAE CPGs to improve the care of persons with epilepsy.  相似文献   
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29.

Objectives

The aim of this study is to evaluate the distribution of the filler size along with the zeta potential, and the integrity of silane-bonded filler surface in different types of restorative dental composites as a function of the material age condition.

Materials and methods

Filtek P60 (hybrid composite), Filtek Z250 (small-particle filled composite), Filtek Z350XT (nanofilled composite), and Filtek Silorane (silorane composite) (3M ESPE) were tested at different stage condition (i.e., fresh/new, aged, and expired). Composites were submitted to an accelerated aging protocol (Arrhenius model). Specimens were obtained by first diluting each composite specimen in ethanol and then dispersed in potassium chloride solution (0.001 mol%). Composite fillers were characterized for their zeta potential, mean particle size, size distribution, via poly-dispersion dynamic light scattering. The integrity of the silane-bonded surface of the fillers was characterized by FTIR.

Results

The material age influenced significantly the outcomes; Zeta potential, filler characteristics, and silane integrity varied both after aging and expiration. Silorane presented the broadest filler distribution and lowest zeta potential. Nanofilled and silorane composites exhibited decreased peak intensities in the FTIR analysis, indicating a deficiency of the silane integrity after aging or expiry time.

Conclusion

Regardless to the material condition, the hybrid and the small-particle-filled composites were more stable overtime as no significant alteration in filler size distribution, diameter, and zeta potential occurred. A deficiency in the silane integrity in the nanofilled and silorane composites seems to be affected by the material stage condition.

Clinical significance

The materials conditions tested in this study influenced the filler size distribution, the zeta potential, and integrity of the silane adsorbed on fillers in the nanofilled and silorane composites. Thus, this may result in a decrease of the clinical performance of aforementioned composites, in particular, if these are used after inappropriate storage conditions.
  相似文献   
30.
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