Search results for "Microscope"
showing 10 items of 1412 documents
The Harderian Gland of the Djungarian Hamster (<i>Phodopus sungorus</i>): Light- and Electron-Microscopical Investigations
1993
The Harderian gland of the Djungarian hamster Phodopus sungorus was investigated by light and electron microscopy in adult animals of both sexes, held under either long or short photoperiods. These glands have a tubuloalveolar structure. Epithelial cells were seen as small cylindric cells with a large, round nucleus located basally, many small vacuoles distributed throughout the cytoplasm (type I cells) or as rather broad cells with larger vacuoles (type II cells). The ratio of both cell types differed from 1:1 to 2:1 (type I:type II), regardless of the animal’s sex. In the electron microscope, abundant smooth endoplasmic reticulum of the vesicular type and rod-like or oval-shaped mitochond…
Suture needles in Oral Surgery: Alterations depending on the type and number of sutures
2011
This study examined whether the number and type of sutures used in oral surgery influence two ad hoc variables (incision plane and displaced area), which are two variables related to whether the suture needle is suitable for the task. Seventy-five TB-15 needles were studied, which were used to suture between zero and three mucosa and/subperiosteal sutures, producing 15 groups with 5 needles in each one. The incision plane and displaced area were measured for each group, which are two variables related to how the needle has worn and altered. Statistical treatment was conducted using the Kruskal-Wallis H test to compare multiple values and the Mann-Whitney U test to compare pairs. A multi-sta…
Surface Topographies of Glaucoma Drainage Devices and Their Influence on Human Tenon Fibroblast Adhesion
2010
PURPOSE. This study was performed to investigate the surface topography of different glaucoma drainage devices and to determine the effects of surface roughness on cell adhesion of cultured human tenon fibroblasts.METHODS. The surface topography of four widely used devices (Ahmed FP7 and Ahmed S-2; New World Medical, Inc., Rancho Cucamonga, CA; Baerveldt BG101-350; Advanced Medical Optics, Irvine, CA; and Molteno S1; Molteno Ophthalmic Ltd., Dunedin, New Zealand) was investigated by scanning electron microscopy, and roughness was quantified by white-light confocal microscopy. Cells were grown for 72 hours on the surfaces of implants affixed to standard culture dishes. The cells were labeled…
Bond strength of cemented fiber posts to teeth with simulated internal root resorption
2020
Made available in DSpace on 2021-06-25T10:58:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 Background: Teeth with internal root resorption (IRR) have guarded prognosis, considering that IRR defect could influence on the post bond strength. The aim of this study was to evaluate the bond strength and the bond interface between different glass fiber-reinforced posts (FRP) after cementation in teeth with simulated internal root resorption (IRR). Material and Methods: Forty-five (45) human premolar roots with simulated IRR were embedded in acrylic resin blocks and cross-sectioned into two segments, enabling them to be re-approximated by screws. Intracanal medication was inserte…
The Effect of surface topographical changes of two different surface treatments rotary instrument
2018
Background One of the major innovations in endodontics has been the introduction of nickel-titanium (NiTi) alloy. This study evaluated the surface topographical changes of two different surface treatments rotary instrument after instrumentation and sterilization. Material and Methods 240 Extracted teeth were included in this study. 90 new AlphaKite and Revo-S NiTi rotary instruments were selected and divided into two groups (Group A 45 AlphaKite and group B 45 Revo-S). Each group were divided into three subgroups: (A1, B1) n=5 files were used as a control, (A2,B2) n=20 files were used to prepare three root canals using endodontic rotary motor then sterilized by autoclave for one cycle under…
Efficacy of NaOCl/H2O2irrigation and GaAlAs laser in decontamination of root canals in vitro
2003
Background and Objectives To investigate the bactericidal effect of an 809 nm semiconductor laser alone, and in combination with NaOCl/H2O2 irrigation in root canals in vitro. Study Design/Materials and Methods A total of 72 human single-rooted teeth extracted for periodontal reasons were included. The crowns were removed, the roots shortened to a length of 12 mm, and the canals enlarged up to an apical size of #50 file. The specimens were autoclaved and incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Laser irradiation was performed on a PC-controlled XY translation stage. A 200 micron optic fiber was used. Twelve specimens were irradiated at a power output of 1.5, 3.0,…
Skin chromophore mapping by modified video-microscope
2013
Possibilities to map skin chromophores using a modified low-cost digital video-microscope is discussed. The device comprises CMOS digital imaging sensor, four-colour LED illumination system and image acquisition optics. The main goal is to obtain a set of spectral images of the skin area of interest for further conversion into maps of the main skin chromophores
Skin chromphore mapping by means of a modified video-microscope for skin malformation diagnosis
2013
Many spectral imaging devices are commercially available and used to detect certain skin pathology; however an alternative cost-efficient device can provide an advanced spectral analisys of skin. Multispectral device for diagnosis of pigmented skin lesions was developed and tested. Possibilities to map skin chromophores using a modified low-cost digital video-microscope is discussed. It was adapted for an advanced skin microscopy and used for detailed spectral analysis of skin. The device comprises CMOS digital imaging sensor, four-colour LED illumination system and image acquisition optics. The main goal is to obtain a set of spectral images of the skin area of interest for further convers…
Experimental reimplantation utilizing microvascular anastomosis in animals.
1977
Summary The use of the operating microscope and special microsurgical instruments make it possible to achieve successful anastomosis of blood vessels of less than 1 mm in diameter. Microvascular surgery offers newer possibilities in the transplantation of dermisfat grafts, and has led to an unusually high degree of success in the reimplantation of tissues. This paper describes a technique for microvascular anastomosis in animal experiment, using as a model the reimplantation of a completely amputated rabbit ear. In 10 amputated rabbit ears, the central auricular artery with a diameter of 0.5 mm and the two marginal auricular veins with diameter of 0.5–1.0 mm were microsurgically anastomosed…
Automatic scanning of large tissue areas in neurosurgery using optical coherence tomography
2012
Background With its high spatial and temporal resolution, optical coherence tomography (OCT) is an ideal modality for intra-operative imaging. One possible application is to detect tumour invaded tissue in neurosurgery, e.g. during complete resection of glioblastoma. Ideally, the whole resection cavity is scanned. However, OCT is limited to a small field of view (FOV) and scanning perpendicular to the tissue surface. Methods We present a new method to use OCT for scanning of the resection cavity during neurosurgical resection of brain tumours. The main challenges are creating a map of the cavity, scanning perpendicular to the surface and merging the three-dimensional (3D) data for intra-ope…