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71.
Using currently available equipment for panoramic hysteroscopy, the size of images viewed cannot be accurately judged because of the magnifying and distorting effects of the objective lens. This study has demonstrated that magnification by the hysteroscope lens can alter the apparent size of images by up to 27%. An additional effect of lens distortion can alter the apparent size of images viewed by up to 28%, depending on the position of the image in the field of view. These effects are independent and may be additive. Thus, the apparent size of intrauterine structures at hysteroscopy may bear little resemblance to their actual size. Image-correction methods are described which reduce the effects of image magnification on the apparent size of an object viewed through the hysteroscope to 7%, and the effect of distortion to 3 %. This technique can greatly improve the accuracy of measurement at hysteroscopy, and has been utilized in this study for the precise measurement of superficial endometrial vascular diameter (mean+/-SEM) in 34 Norplant users (120+/-11.6 microm) and 20 women with spontaneous menorrhagia (74+/-7.2 microm). It has also confirmed the presence of scattered dilated vessels (up to 777 microm in diameter) on the endometrial surface in some Norplant users. 相似文献
72.
LK Trejdosiewicz R Morton Y Yang RE Banks PJ Selby J Southgate 《Canadian Metallurgical Quarterly》1998,10(10):756-765
Interleukin 4 (IL-4) inhibits carcinoma cell growth and promotes expression of differentiation-associated products by normal and malignant epithelial cells. The effects of IL-4 and IL-13 on expression of the CD44 transmembrane adhesion receptor were examined in human epithelial cell lines of colonic (HT-29, CaCo-2, DLD-1, T84), breast (MCF-7, ZR75-1) and liver (Hep-G2, PLC/PRF/5) origins as well as mitogen-activated and resting peripheral blood lymphocytes (PBL) and T cell lines (Jurkat, HUT78). Liver and Jurkat cells were negative for CD44. Colonic, breast and HUT78 cells expressed CD44 constitutively and all except DLD-1 and HUT78 also expressed CD44 splice variant (CD44v) epitopes. All cell lines expressed IL-4 receptors, but IL-4 and IL-13 induced upregulation of CD44 only in the colonic cell lines. CD44v was also upregulated, but there was no de novo induction of CD44v in variant-negative cells and no de novo expression of CD44 in the CD44(-) lines. CD44 upregulation in mitogen-activated PBL was not increased by IL-4 and IL-13 and was not inhibited by neutralizing antibodies. Other cytokines tested [interferon gamma (IFN-gamma, tumour necrosis factor alpha (TNF-alpha), transforming growth factor beta1 (TGF-beta1) and IL-6] did not affect CD44 core epitope expression in the cell lines tested. 相似文献
73.
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75.
The long cane can be used as a mobility aid for visually handicapped people. According to a questionnaire completed by Japanese cane users, it seems they are not always satisfied with using long canes for a variety of reasons. In this study, hand-transmitted vibration from the long cane due to tapping the ground was measured because an exposure to repeated shock-type tapping vibration may affect the hand-arm system. A sighted female wearing a blindfold participated. The measurement was carried out in different conditions with three different ground materials both indoor and outdoors. The vibration at three axes of the cane grip and one axis at the wrist were measured. The pinch forces between an index finger and the grip were also measured using a strain gauge in order to observe how the vibration characteristics depend on the changing forces. Measurement, evaluation and assessment were based on the International Standard (ISO 5349). The estimated daily exposure time and the transmissibility were obtained in order to investigate the severity of the hand-transmitted vibration caused by the long cane. It was found that the characteristics of tapping vibration depend on different measurement conditions and the vibration might be associated with a health risk over a long life span. 相似文献
76.
BR Babu SJ Zhu AV Ramayya JH Hamilton LK Peker MG Wang TN Ginter J Kormicki WC Ma JD Cole R Aryaeinejad K Butler-Moore YX Dardenne MW Drigert GM Ter-Akopian YT Oganessian JO Rasmussen S Asztalos IY Lee AO Macchiavelli SY Chu KE Gregorich MF Mohar S Prussin MA Stoyer RW Lougheed KJ Moody JF Wild 《Canadian Metallurgical Quarterly》1996,54(2):568-571
77.
Preventive maintenance and repair during a mission have an important effect on the dependability of ships' systems. Space and weight limitations mean that not all repairs can be carried out during the mission and this limits the dependability which can be achieved. Using a simple diesel generator arrangement as an example, this paper discusses the relationships between dependability, downtime for preventive maintenance, proportion of failures repairable at sea, and equipment failure rate. 相似文献
78.
LK Sorensen A Theilgaard J Thomsen K Zilstorff 《Canadian Metallurgical Quarterly》1977,83(3-4):266-271
A neuro-psychological study is described comprising 19 patients with Meniere's Disease who were participating in an experimental lithium therapy programme. The patients evidenced an organic dysfunction which is not entirely periphearl. The interpretation of the results are not incompatible with an attempt to reconcile neuro-psychological and psycho-somatic viewpoints regarding etiological aspects of Meniere's Disease. An evaluation of the lithium effect was performed. 相似文献
79.
Angiotensin II (AII), found in seminal plasma, has been shown to stimulate capacitation in uncapacitated mammalian spermatozoa. The present study investigated the location of AII receptors on spermatozoa and AII's mechanism of action. AT1 type receptors for AII are present on the acrosomal cap region and along the whole of the flagellum of both mouse and human spermatozoa. Because combinations of low concentrations of AII and either calcitonin or fertilization-promoting peptide (FPP), both known to regulate the adenylyl cyclase (AC)/cAMP signal transduction pathway, elicited a significant response, this study investigated the hypothesis that these peptides act on the same pathway. AII was shown to significantly stimulate cAMP production in both uncapacitated and capacitated mouse spermatozoa and this was associated with increases in protein tyrosine phosphorylation. Using an anti-phosphotyrosine antibody to visualize the location of tyrosine phosphoproteins within individual cells, AII significantly stimulated phosphorylation within 20 min in both the head, especially in the acrosomal cap region, and the flagellum, especially in the principal piece, of uncapacitated mouse spermatozoa; combined AII + FPP was stimulatory within 5 min. In addition, Western blotting revealed that AII stimulation increased phosphorylation in a number of tyrosine phosphoproteins in both uncapacitated and capacitated mouse spermatozoa, with some being altered only in the latter category of cells. These results support the hypothesis that AII stimulates AC/cAMP in mammalian spermatozoa. 相似文献
80.
Monitoring of ethylene by a pulsed quantum cascade laser 总被引:2,自引:0,他引:2
We report on the development and performance of a gas sensor based on a quantum cascade laser operating at a wavelength of approximately 10 microns to measure ethylene (C2H4) concentrations by use of a rotational component of the fundamental nu 7 band. The laser is thermoelectrically cooled and operates in a pulsed mode. The influence of pulse-to-pulse fluctuations is minimized by use of a reference beam and a single detector with time discriminating electronics. Gas absorption is recorded in a 100-m optical path-length astigmatic Herriott cell. With a 10-kHz pulse repetition rate and an 80-s total acquisition time, a noise equivalent sensitivity of 30 parts per billion has been demonstrated. The sensor has been applied to monitor C2H4 in vehicle exhaust as well as in air collected in a high-traffic urban tunnel. 相似文献