scholarly journals Scanning Electron Microscopy of the Effect of Short-term Hormonal Therapy on Postmenopausal Endometrium

1978 ◽  
Vol 83 (3) ◽  
pp. 175-183 ◽  
Author(s):  
Eva Nathan ◽  
Mogens Knoth ◽  
B. Ove Nilsson
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Hormonal Therapy ◽  
Short Term ◽  
Scanning Electron

Non-Thrombogenic Characteristics of Hybrid Vascular Prostheses

1979 ◽  
Author(s):  
P.N. Sawyer ◽  
B. Stanczewski
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Protein Structure ◽  
Thrombus Formation ◽  
Vascular Prosthesis ◽  
Short Term ◽  
Vascular Prostheses ◽  
Complete Occlusion ◽  
Dacron Prostheses ◽  
Scanning Electron

In our continuing efforts to develop a compound, coated vascular prosthesis, combining the best characteristics of biologic and nonbiologic materials, we have produced a hybri graft with pseudo biological coating. Five types of velour and knit dacron prostheses, have been cross linked subsequently with negatively charged proteins. Albumin and gelatin were used to coat the prosthesis or the combination of both. Following electrochemical characterization coated prostheses were implanted into the carotid and femoral arteries of dogs for 1 sec. 2 hr. and 1 mo. Preparations that showed promising short term results were implanted in the abdominal aorta of dogs for 18 months. Controls included uncoated prostheses and prostheses that had been coated but not negatively charged. Upon removal, the grafts were examined for thrombi and other luminal narrowings (photography, light and scanning electron microscopy). Fifty two uncoated and coated grafts have been examined. These exhibit a range of thrombus formation, from none to complete occlusion, in the various knit/coating combinations. We believe these hybrid prostheses will prove to be very useful in vascular reconstructive surgery due to (i) the nonthrombogenic characteristics of the negatively charged protein structure, (ii) more uniform healing and (iii) ease of implantation since preclotting is not necessary.

Load Concentrations around Crystal Aggregates in Articular Cartilage under Short-Term Loading

1993 ◽  
Vol 207 (1) ◽  
pp. 35-40 ◽  
Author(s):  
S E Clift ◽  
A Hayes ◽  
A W Miles ◽  
B Harris ◽  
P A Dieppe
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Articular Cartilage ◽  
Fibrous Tissue ◽  
Joint Diseases ◽  
Stress Concentrations ◽  
Large Crystal ◽  
Short Term ◽  
Cartilage Layer ◽  
Scanning Electron

The deposition of crystals in joints is a feature of a number of joint diseases. Crystals are frequently observed on the surface of articular cartilage and in the mid-zone. The purpose of this investigation was to model the stress concentrations in the mid-zone of the cartilage layer arising from the presence of large crystal aggregates. Scanning electron microscopy was used to determine the geometry and distribution of crystal aggregates within the cartilage layer. Finite element and photoelastic approaches were then used to predict the stress distribution around spherical aggregates 50 and 100 μm in diameter. The implication of the results is that very densely packed and tightly bound spherical aggregates will themselves carry a certain amount of load. However, less tightly packed aggregates, perhaps interspersed with fibrous tissue, are potentially much more damaging.

Short-term temperature impact on simultaneous biological nitrogen-sulphur treatment in EGSB reactor

2016 ◽  
Vol 74 (7) ◽  
pp. 1610-1618 ◽  
Author(s):  
Michal Sposob ◽  
Carlos Dinamarca ◽  
Rune Bakke
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Biological Treatment ◽  
Granular Sludge ◽  
Molar Ratio ◽  
Short Term ◽  
Temperature Impact ◽  
Granule Surface ◽  
Biological Nitrogen ◽  
Scanning Electron

Sulphides are present in many wastewater streams; their removal is important due to corrosiveness, toxicity and unpleasant odour, and can be carried out by anaerobic biological treatment. This study focuses on the temperature effect (25–10 °C) on an expanded granular sludge bed (EGSB) reactor for sulphide removal using nitrate as electron acceptor. The reactor was run at a NO3−/HS− molar ratio of 0.35 and pH of 8.5–9.0. Samples were analysed by ion chromatography (NO3−, SO42− and S2O32−), spectrophotometry (S2−) and by scanning electron microscopy (SEM). S2− and NO3− removal was 99.74 ± 0.04 and 99.5 ± 2.9%, respectively. Sulphur (S0) was found on the outer granule surface and struvite inside the granule, by SEM. Sulphide conversion to sulphur was up to 76%. Temperature transitions and levels influenced S2O32− and SO42− concentrations.

scholarly journals Maxon is an Optimal Suture for Bile Duct Anastomoses in Pigs

HPB Surgery ◽  
1993 ◽  
Vol 7 (2) ◽  
pp. 111-124 ◽  
Author(s):  
Phil Jeans ◽  
Pauline Hall ◽  
Yong-Feng Liu ◽  
Robert A. Baker ◽  
Andrew Holt ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bile Duct ◽  
Light Microscopy ◽  
Short Term ◽  
Polyglactin 910 ◽  
Bile Duct Anastomosis ◽  
Absorption Characteristics ◽  
Scanning Electron

Background. Three commonly used sutures were tested in a pig model of bile duct anastomosis to assess their relative contributions to inflammation and scarring.Methods. Thirty pigs were randomised to bile duct division and anastomosis with either polyglyconate (Maxon), polyglactin 910 (Vicryl) or polypropylene (Prolene). Half the animals were sacrificed at two weeks and the remainder at 23 weeks. Anastomoses were assessed by cholangiography, scanning electron microscopy and light microscopy.Results. There was less short term histological reaction with the two monofilament materials, Prolene and Maxon, compared to the braided suture Vicryl. Maxon was associated with less long term inflammation than Prolene, was found to handle better, and has an advantage over Prolene by being absorbable.Conclusion. Maxon is an optimal suture for bile duct anastomoses. Its long term absorption characteristics make it suitable for situations where bile duct healing may be delayed.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

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