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1.
Purpose: The effects of radiation exposure are long-lasting. Long-term monitoring is imperative to diagnose late effects and improve our far-sightedness about possible events in the future. A radiation accident occurred in Istanbul in 1998 that resulted in mild to moderate acute radiation syndrome (ARS). In this study we aimed to investigate the changes in hematological parameters at the long-term follow-up of ARS patients.

Methods: Ten adults were hospitalized after exposure to a 60Co source. Seven were diagnosed as having ARS and had severe and symptomatic pancytopenia. All of the exposed people recovered following intensive treatment. Treatment was supportive with transfusion, granulocyte-colony stimulating factor, and anti- infective management covering antifungal agents. Patients were closely monitored. Nine years after the accident, the initial and follow-up complete blood count examinations and peripheral blood smears (PBS) were comparatively evaluated by an experienced hematologist. The hematological laboratory values of the patients on admission, after treatment, and nine years after the accident were documented and compared.

Results: Biodosimetric analysis revealed that whole-body doses ranged from 1–1.9 Gy. All subjects have shown complete recovery of the hematological laboratory values after treatment. All but one of the subjects showed complete blood cell recovery. The improvement of the blood cell count of the excepted patient stalled at a mildly reduced level and his bone marrow was still hypocellular nine years after the accident; however, no malignant changes were detected. Values at admission were significantly different compared with post treatment and present values of all patients. Post treatment and follow-up values were similar. One of the patients died of lung cancer. None of the patients developed hematological malignancy.

Conclusions: In this study, the recovery from ARS was complete after treatment. The small population, short follow-up period, and the relatively small doses resulted in no long-term adverse effects, as would be predicted.  相似文献   
2.

Introduction

The diagnostic accuracy of the FAST exam performed by EM residents were shown to be similar to radiology residents. However, in the last 2 decades, an extended-FAST (E-FAST) protocol including thoracic examination to exclude pneumo- and hemothorax was introduced. The accuracy of emergency physicians (EPs) while performing E-FAST is a less studied area, especially in Europe. The aim of this study was to compare the diagnostic accuracy of the E-FAST exam performed by EM residents with the results of CT scan as a gold standard.

Methods

This was a prospective, observational, diagnostic accuracy study conducted at the ED of a Level 1 Trauma Center. All consecutive adult multiple trauma patients were eligible, and any patient in whom thoraco-abdominal CT was ordered were recruited. Unstable and unavailable patients were excluded. E-FAST examination was performed by EPs as the index test, and CT examinations reported by a blinded academic radiology faculty was the gold standard.

Results

A total of 140 patients were recruited from eligible 144 patients. The final study population was 132 for abdominal and 130 for thorax examinations. In this study, AUC of E-FAST was 0.71 for abdominal free fluid, 0.87 for pneumothorax and 1.00 for pleural effusion. The sensitivity was 42.9% and specificity was 98.4%. The + LR for abdominal free fluid was 26.8 and ? LR was 0.58.

Conclusion

E-FAST examination has an excellent specificity. However, the sensitivity of the test is not high enough to rule-out thoraco-abdominal injuries in trauma patients when performed by EPs.  相似文献   
3.
Background: To characterize the methicillin-resistant Staphylococcus aureus (MRSA) clones present in Istanbul, 102 MRSA isolates collected during a 5-year period at the Istanbul Medical Faculty Hospital were characterized using microarray analysis and phenotypic resistance profiles.Methods: Resistance to methicillin was detected with a cefoxitin disk diffusion assay and confirmed with a MRSA-agar and MRSA detection kit. Antimicrobial susceptibility testing was performed by a disk diffusion assay and interpreted according to the 2012 guidelines of the Antibiogram Committee of the French Society for Microbiology. Decreased susceptibility to glycopeptides was confirmed using the population analysis profile-area under the curve (PAP-AUC) method. The presence of the mecA gene was detected by polymerase chain reaction. Bacterial DNA was extracted according to the manufacturer''s recommended protocol using commercial extraction kits. Strains were extensively characterized using the DNA microarray.Results: Isolates were grouped into six clonal complexes. The most frequently detected clone was the Vienna/Hungarian/Brazilian clone (ST239-MRSA-III), which accounted for 53.9% of the isolates. These isolates were resistant to multiple antibiotics, particularly penicillin, tetracycline, rifampicin, kanamycin, tobramycin, gentamicin, levofloxacin, erythromycin, lincomycin and fosfomycin. Furthermore, three isolates were detected by population analysis profile as heterogeneous vancomycin-intermediate S. aureus (hVISA). The UK-EMRSA-15 clone (ST22-MRSA-IV PVL negative) was detected in 9.8% of the isolates and was mainly susceptible to all anti-staphylococcal antibiotics. Seven isolates (6.9%) were positive for PVL genes and were assigned to the CC80-MRSA-IV clone (European CA-MRSA clone, three isolates), ST8-MRSA-IV clone (USA300 clone, two isolates, one ACME-positive) or ST22-MRSA-IV clone (“Regensburg EMRSA” clone, two isolates). All other clones were detected in one to six isolates and corresponded to well-known clones (e.g., Pediatric clone, Dublin EMRSA clone, WA MRSA-54/63, WA MRSA-1/57).Conclusions: This work highlighted both the high prevalence of ST239-MRSA-III clone and the large diversity of the other MRSA clones detected in a university hospital in Istanbul.  相似文献   
4.
Statement of problemLaser sintering is commonly used for fabricating metal-ceramic restorations. The layer thickness of the sintering process may affect restoration adaptation. However, limited information is available regarding its impact.PurposeThe purpose of this in vitro study was to compare the marginal and internal adaptation of laser-sintered cobalt-chromium single crown frameworks sintered with layer thicknesses of 25 and 50 μm.Material and methodsThirty resin dies that represented prepared single molar abutment teeth were prepared by using a 3-dimensional printer and were divided into 3 groups (n=10) according to the method used for fabricating metal frameworks: group C, metal frameworks fabricated by using the lost-wax method (control); group L25, metal frameworks fabricated by using direct metal laser melting with a layer thickness of 25 μm; and group L50, metal frameworks fabricated by using direct metal laser melting with a layer thickness of 50 μm. After fabricating the metal frameworks, 15 vertical marginal discrepancy measurements were made in each axial region (mesial, distal, buccal, and lingual) using a stereomicroscope. Next, all the specimens were sectioned from the midline, and 5 internal discrepancy measurements were made in each internal region (inner marginal, axial, and occlusal). The data were analyzed statistically by using 1-way ANOVA, the Tukey honestly significant difference, and Tamhane T2 tests (α=.05).ResultsThe highest marginal and internal discrepancy values were obtained for metal frameworks in group C, and these values were significantly different (P<.001) from those obtained for metal frameworks in the other 2 groups. No significant difference was observed in the marginal and internal discrepancy values of metal frameworks in groups L25 and L50.ConclusionsThese results indicate that layer thickness does not affect the adaptation of laser-sintered metal frameworks, yet both sintering parameters yielded significantly lower mean marginal discrepancy values than the cast group.  相似文献   
5.
6.
Experts discussed the definition, natural history, pathologic features, pathogenesis, electroclinical, neurophysiological, neuropsychological, structural and functional imaging findings, as well as surgical outcome in mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). After a long-lasting consensus process the ILAE Commission Neurosurgery of epilepsy accepted the resulting conclusions as state-of-the art report on MTLE-HS. The majority of contributors considered MTLE-HS to represent a sufficient cluster of signs and symptoms to make up a syndromic diagnostic entity.  相似文献   
7.

Statement of problem

Achieving natural tooth appearance with sufficient mechanical strength is one of the most challenging issues of computer-assisted design and computer-assisted manufacturing (CAD-CAM) materials. However, limited evidence is available regarding their optical and mechanical properties for proper and evidence-based material selection in clinical practice.

Purpose

The purpose of this in vitro study was to assess and compare the translucency and biaxial flexural strength of 5 monolithic CAD-CAM restorative materials.

Material and methods

Disk-shaped specimens (n=30) of each material (Lava Ultimate [LU], Vita Enamic [VE], Vitablocs Mark II [VMII], Vita Suprinity [VS], and IPS e.max CAD [IPS]) with a diameter of 12 mm and a thickness of 1.2 ±0.05 mm were prepared. A spectrophotometer was used to measure the translucency parameter. The specimens were then subjected to a biaxial flexure test using 3 balls and loaded with a piston in a universal testing machine at a cross-head speed of 0.5 mm/min until failure occurred (International Organization for Standardization standard 6872). Weibull statistics were used to evaluate the characteristic strength and reliability of each material. Chemical compositions were analyzed using an energy dispersive spectrometer, and microstructural analysis was conducted using scanning electron microscopy. Data were analyzed using 1-way ANOVA and the Tukey honest significant difference test (α=.05).

Results

Significant differences were found among the materials concerning translucency and biaxial flexural strength (P<.05). The highest mean transparency value was obtained in the VS group, whereas the lowest mean value was obtained in the VE group. The VS group produced the highest mean biaxial flexural strength, followed by the IPS, LU, VE, and VMII groups.

Conclusions

Based on the results of the present study, zirconia-reinforced glass-ceramic revealed higher mean translucency and biaxial flexural strength than resin nanoceramic, feldspathic ceramic, lithium disilicate ceramic, and dual-network ceramic.  相似文献   
8.

Statement of problem

A recommended minimum thickness for monolithic zirconia restorations has not been reported. Assessing a proper thickness that has the necessary load-bearing capacity but also conserves dental hard tissues is essential.

Purpose

The purpose of this in vitro study was to evaluate the effect of thickness and surface modifications on monolithic zirconia after simulated masticatory stresses.

Material and methods

Monolithic zirconia disks (10 mm in diameter) were fabricated with 1.3 mm and 0.8 mm thicknesses. For each thickness, 21 disks were fabricated. The specimens of each group were further divided into 3 subgroups (n=7) according to the surface treatments applied: untreated (control), airborne-particle abrasion with 50-μm Al2O3 particles at a pressure of 400 kPa at 10 mm, and grinding with a diamond rotary instrument followed by polishing. The biaxial flexure strength was determined by using a piston-on-3-balls technique in a universal testing machine. Flexural loading was applied with a 1.4-mm diameter steel cylinder, centered on the disk, at a crosshead speed of 0.5 mm/min until fracture occurred. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed. The data were statistically analyzed with 2-way ANOVA, Tamhane T2, 1-way ANOVA, and Student t tests (α=.05).

Results

The 1.3-mm specimens had significantly higher flexural strength than the 0.8-mm specimens (P<.05). Airborne-particle abrasion significantly increased the flexural strength (P<.05). Grinding and polishing did not affect the flexural strength of the specimens (P>.05).

Conclusions

The mean flexural strength of 0.8-mm and 1.3-mm thick monolithic zirconia was greater than reported masticatory forces. Airborne-particle abrasion increased the flexural strength of monolithic zirconia. Grinding did not affect flexural strength if subsequently polished.  相似文献   
9.
10.
The Kyrgyz government declared a policy of “zero tolerance” for torture and began reforms to stop such practice, a regular occurrence in the country's daily life. This study presents the results of 10 forensic evaluations of individuals alleging torture; they represent 35% of all criminal investigations into torture for the January 2011–July 2012 period. All individuals evaluated were male with an average age of 34 years. Police officers were implicated as perpetrators in all cases. All individuals reported being subjected to threats and blunt force trauma from punches, kicks, and blows with objects such as police batons. The most common conditions documented during the evaluations were traumatic brain injury and chronic seizures. Psychological sequelae included post-traumatic stress disorder and major depressive disorder, which was diagnosed in seven individuals. In all cases, the physical and psychological evidence was highly consistent with individual allegations of abuse. These forensic evaluations, which represent the first ever to be conducted in Kyrgyzstan in accordance with Istanbul Protocol standards, provide critical insight into torture practices in the country. The evaluations indicate a pattern of brutal torture practices and inadequate governmental and nongovernmental forensic evaluations.  相似文献   
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