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1.
2.
Summary Split or full thickness eyelid defects resulting from tumor destruction or surgical excision present a dilemma for plastic and reconstructive surgeons. Full thickness eyelid replacement requires composite grafting of the skin, together with tarsal support of its substitute and mucosa. The flap described by Fricke in 1829 was used for reconstruction of anterior lamella in six lower eyelid defects. In three of our cases chondromucosal grafts taken from nasal septum were utilized for posterior lamella repair. The results have been satisfactory from a functional and cosmetic standpoint. 相似文献
3.
Summary The serratus anterior muscle in the rat is supplied by the serratus division of thoracodorsal vessels, in a pattern similar to man [2]. The serratus anterior muscles were transferred to the groin area as a free muscle flap in 17 rats and as a free muscle graft in 13 rats. In the free muscle flap group, the serratus anterior muscles of 8 of 10 rats survived; histological examination showed them to be viable and the vascular anastomoses were patent at the 30th day. In the free muscle graft group, all of the muscle grafts became necrotic. As a result, it is concluded that the microvascular transfer of serratus anterior muscles in rats is a useful small animal model for microsurgical laboratory training of clinical free flap transfers and also for performing pharmacological and biochemical studies in transplanted muscle. 相似文献
4.
Effect of surface conditioning methods on the bond strength of luting cement to ceramics 总被引:9,自引:0,他引:9
OBJECTIVES: This study evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA based luting cement to six commercial dental ceramics. METHODS: Six disc shaped ceramic specimens (glass ceramics, glass infiltrated alumina, glass infiltrated zirconium dioxide reinforced alumina) were used for each test group yielding a total number of 216 specimens. The specimens in each group were randomly assigned to one of the each following treatment conditions: (1) hydrofluoric acid etching, (2) airborne particle abrasion, (3) tribochemical silica coating. The resin composite luting cement was bonded to the conditioned and silanized ceramics using polyethylene molds. All specimens were tested at dry and thermocycled (6.000, 5-55 degrees C, 30 s) conditions. The shear bond strength of luting cement to ceramics was measured in a universal testing machine (1 mm/min). RESULTS: In dry conditions, acid etched glass ceramics exhibited significantly higher results (26.4-29.4 MPa) than those of glass infiltrated alumina ceramics (5.3-18.1 MPa) or zirconium dioxide (8.1 MPa) (ANOVA, P<0.001). Silica coating with silanization increased the bond strength significantly for high-alumina ceramics (8.5-21.8 MPa) and glass infiltrated zirconium dioxide ceramic (17.4 MPa) compared to that of airborne particle abrasion (ANOVA, P<0.001). Thermocycling decreased the bond strengths significantly after all of the conditioning methods tested. SIGNIFICANCE: Bond strengths of the luting cement tested on the dental ceramics following surface conditioning methods varied in accordance with the ceramic types. Hydrofluoric acid gel was effective mostly on the ceramics having glassy matrix in their structures. Roughening the ceramic surfaces with air particle abrasion provided higher bond strengths for high-alumina ceramics and the values increased more significantly after silica coating/silanization. 相似文献
5.
Dr. Bektaş Açikgöz Mehmet Turgut Osman Ekin Özcan Tunçalp Özgen Beyhan Demirhan Şevket Ruacan 《Lasers in medical science》1992,7(1-4):49-53
In this study we have investigated the negative influence of CO2 and Nd-YAG laser irradiation on rapid cranial regeneration and whether it has any use in certain types of craniosynostosis.
Twenty-two newborn rats were used in the study. Both CO2 and Nd-YAG laser irradiation, which was applied to free bony edges after, suturectomies, resulted in a significant decrease
in skull regeneration. Histopathological examinations revealed severe degeneration caused by both types of laser energies. 相似文献
6.
Kallakuri S Cavanaugh JM Ozaktay AC Takebayashi T 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,148(4):419-424
Diffuse axonal injury (DAI) is seen as widespread damage in the white matter of brain characterized by morphological changes
to axons throughout the brain and brain stem. The current study attempted to investigate the effect of increasing impact energy
on the presence and severity of DAI in corpus callosum (CC). DAI was induced in adult male Sprague-Dawley rats using an injury
model adapted from Marmarou et al. in 1994. A 450-g cylindrical brass weight was dropped from three different heights (2.0 m,
1.5 m and 1.0 m) on to a metal helmet affixed to the skull of the rats. In the sham group, rats underwent a surgical procedure
with no impact. After a 24-h survival period the animals were transcardially perfused. The brain was removed and the cerebral
hemispheres were sectioned with a vibrotome and stained by silver impregnation technique. The CC of all the impacted rats
showed DAI in the form of beaded axons, retraction balls and vacuole-like enlargements. The axonal injury was most severe
in the 2-m group, while mildest in the 1-m group. In the sham group, axons appeared to be normal. This study demonstrates
evidence of graded DAI depending on the impact energy. Such data is useful for mathematical modeling of axonal injury in rat
brain using the same impact parameters and potential determination of injury thresholds for neural trauma.
Electronic Publication 相似文献
7.
Özcan Özdamar Rafael E. Delgado Syed Rahman Carlos Lopez 《Annals of biomedical engineering》1998,26(5):883-891
An innovative acoustic noise canceling method using adaptive Wiener filtering (AWF) was developed for improved acquisition of distortion product otoacoustic emissions (DPOAEs). The system used one microphone placed in the test ear for the primary signal. Noise reference signals were obtained from three different sources: (a) pre-stimulus response from the test ear microphone, (b) post-stimulus response from a microphone placed near the head of the subject and (c) post-stimulus response obtained from a microphone placed in the subjects nontest ear. In order to improve spectral estimation, block averaging of a different number of single sweep responses was used. DPOAE data were obtained from 11 ears of healthy newborns in a well-baby nursery of a hospital under typical noise conditions. Simultaneously obtained recordings from all three microphones were digitized, stored and processed off-line to evaluate the effects of AWF with respect to DPOAE detection and signal-to-noise ratio (SNR) improvement. Results show that compared to standard DPOAE processing, AWF improved signal detection and improved SNR. © 1998 Biomedical Engineering Society.
PAC98: 4364Jb, 4360-c, 8790+y 相似文献
8.
Gürpinar OA Tuzlakoğlu K Onur MA Tümer A Serdar MA Unal N Pişkin E 《Journal of biomaterials science. Polymer edition》2003,14(6):589-600
In this study, attachment and growth of Baby Hamster Kidney (BHK) cells on ethylene diamine (EDA)-plasma-treated poly(L-lactide/epsilon-caprolactone) biodegradable copolymer films were investigated. The co-polymer (Mw: 58000; Mn: 35000 and PI 1.60) was synthesised by ring-opening polymerization of the respective dimers with using stannous octoate as the catalyst. The final ratio of L-lactide to epsilon-caprolactone obtained by 1H-NMR was 87:13. The co-polymer films were treated with the EDA-plasma in a glow-discharge apparatus. The BHK-30 cell line was cultured on plain and EDA-plasma-treated films and their pre-wetted forms (with ethanol and/or cell culture medium before use). Cell attachment and growth were followed. Alkaline phosphatase (ALP) activity and glucose uptake in cell culture medium were also investigated. There was no attachment in the first 12 h. Glow-discharge treatment increased significantly the attachment and growth. Pre-wetting with ethanol and cell culture medium was also increase significantly both the attachment and growth. 相似文献
9.
Ihsan H. Ciftci Umit Dundar Zafer Cetinkaya Mustafa Kulac Nilay Kiyildi Aycan Turel Deniz Evcik Vural Kavuncu 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(1):70-73
The objective of this study was to investigate the incidence and density of Demodex folliculorum in the patients with rheumatoid arthritis (RA). Forty-one patients with RA and twenty-seven age and sex matched healthy controls
were enrolled in this study. Disease Activity Score (DAS 28) was used for the assessment of disease activity. Out of 41 patients,
33 were females and 8 males. The mean disease duration was 10.9 ± 8.2 years. The mean DAS 28 was 3.8 ± 1.2. No statistically
significant differences in the incidence and density of Demodex mites were found between patients with RA and controls. Although immunosuppression is thought to be a risk factor for the
D. folliculorum infestation no such correlations could be found in the 41 immunosuppressed patients with RA, therefore, further studies with
larger groups are needed. 相似文献
10.
A family with cardiac malformation, cleft lip-palate, short stature, microcephaly, distally placed thumbs, short 2nd and 5th fingers, long and broad 1st toes, broad distance between 1st and 2nd toes and mediodorsal curvature of the 4th toes with syndactyly of the 2nd and 3rd toes has been described as having a new syndrome. While some members of the family had full signs of the syndrome, others had similar but fewer and less severe anomalies of the same structures. The presence of common findings in three generations, its variable expressivity and pleiotropism, and the non-consanguineous history in the parents suggest that the inheritance is autosomal dominant. 相似文献