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1.
OBJECTIVE: Our objective was to determine the interest of laparoscopic assisted vaginal hysterectomy. STUDY DESIGN: Between January 1991 to december 1994, 80 patients had laparoscopically assisted vaginal hysterectomy. We reviewed with particular emphasis characteristic indications, complications. RESULTS: Eighty were performed as laparoscopically assisted vaginal hysterectomy. 14 patients (17.5%) had laparotomy conversion; because of size of uterus in 3 cases, suspected ovarian tumor in 3 cases. Pelvic adherences in 4 cases, urinary tract injuries in 1 case, hypercapnia in 1 case, hemorrhage in 2 cases. 9 patients experienced febrile morbidity and 1 urinary infection. 1 patient received 2 units of packed red blood cells. The hospital stay was 5 days for laparoscopically assisted vaginal hysterectomy versus 5.9 for laparotomic hysterectomy. CONCLUSION: Laparoscopically assisted vaginal hysterectomy offers a technique to convert certain abdominal hysterectomies into vaginal hysterectomies with a 17.5% laparoconversion rate.  相似文献   
2.
Distribution of electric energy by extruded polymer insulated cables continues to be a subject of outstanding relevance in modern industrialized countries all over the world. Dielectric characterization, conduction modelling and finally diagnostics of polymeric insulations are necessary steps towards the development of reliable and less expensive robust technologies of electric power distribution. This paper is devoted to a detailed experimental/theoretical study of the conductive properties of LDPE affected by different levels of degradation by water trees. Water tree layers of different lengths were grown in accelerated conditions and were characterized by water tree kinetics, time-dependent permittivity and polarization current. The polarization current was found to obey a Curie-von Schweidler law whose parameters were used to characterize the effect of ageing time. A new conduction model that takes into account dipole interactions and was obtained from a two-wells Debye model is presented which allows us to give an interpretation of the effect of ageing. This laboratory study was intended to improve the characterization of service power cables aged by water trees  相似文献   
3.
We present new measurements on a Cryogenic Dark Matter Search (CDMS) detector with electron, neutron, and gamma sources. The measurements have been performed to investigate the dead layer of one of the CDMS Z-dependent Ionization Phonon germanium detectors. The dead layer has been studied at both charge electrodes and at different electric field intensities. We also present a method to remove the dependence of athermal phonon measurements on event position.  相似文献   
4.
This paper describes the influence of water trees on dielectric properties of flat samples cut from a HV crosslinked polyethylene (XLPE) cable insulation. In order to obtain experimental results in a short period of time, we used accelerated aging conditions of voltage and frequency as well as different techniques for producing a multitude of artificial water tree inception points. The average value of the water tree permittivity and a law for the time-dependence of permittivity inside the treed degraded areas were deduced from measurements of capacitance and water tree lengths. On the basis of the experimental knowledge of permittivity and water tree length, we determined with analytical numerical methods, the distribution of the electric field for different shapes of treed regions. Because of the increase in length and permittivity of the water tree, the electric field in front of the degraded area is amplified, which is an important factor of risk leading to the electric breakdown  相似文献   
5.
A system is presented to jointly achieve image watermarking and compression. The watermark is a fragile one being intended for authentication purposes. The watermarked and compressed images are fully compliant with the JPEG-LS standard, the only price to pay being a slight reduction of compression efficiency and an additional distortion that can be anyway tuned to grant a maximum preset error. Watermark detection is possible both in the compressed and in the pixel domain, thus increasing the flexibility and usability of the system. The system is expressly designed to be used in remote sensing and telemedicine applications, hence we designed it in such a way that the maximum compression and watermarking error can be strictly controlled (near-lossless compression and watermarking). Experimental results show the ability of the system to detect tampering and to limit the peak error between the original and the processed images.  相似文献   
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7.
沙恩豪塞公园   总被引:1,自引:0,他引:1  
<正>传统营房建筑与生活质量无缘,其建筑布局和建设往往从纯功能方面考虑,而忽略了建筑的生态效应。尽管如此,这些场地仍有其独特的潜质,此类重建项目无疑会减轻城镇的用地负担。  相似文献   
8.
The benzoyl nitrogen mustard derivative of distamycin A, tallimustine, belongs to a new class of alkylating agents, known as DNA minor groove alkylating agents. It alkylates adenine N3 with high sequence specificity, causing no alkylation of guanine N7, the main site of alkylation of clinically used nitrogen mustards such as L-PAM. The present study investigated the in vivo antitumour activity of a combination of tallimustine and melphalan (L-PAM). Two murine tumours were used: i.p. (intraperitoneally) transplanted L1210 leukaemia and i.m. (intramuscularly) transplanted M5076 ovarian reticulum cell sarcoma (M5). In L1210, which is only marginally sensitive to tallimustine, the combination of tallimustine 3 mg/kg i.p. with L-PAM 10 mg/kg i.p. was as effective as 20 mg/kg L-PAM, which is the maximum tolerated dose. In M5, which is sensitive to both drugs, the combination was superior to either drug alone. The results suggest that the combination of tallimustine and L-PAM--or possibly in general, minor groove alkylators and major groove alkylators--may be therapeutically advantageous and therefore should be investigated clinically.  相似文献   
9.
The taxanes are a promising family of anti-tumour drugs that block cell cycle replication by interfering with the microtubule network. The clinical use of these drugs involves some problems related to their low solubility and occurrence of resistance, which is mainly dependent on the multidrug-resistant (MDR) phenotype. To investigate the possible interaction between docetaxel and tamoxifen (TAM), three oestrogen receptor-negative cancer cell lines, MDR- MDA-MB 231, MDR + CEM-VBLr and MCF-7 ADRr, were used. In all three cell lines, the combination of docetaxel and TAM was more effective in terms of growth inhibition than single drug exposure. Isobolic analysis confirmed the presence of synergism in all cell lines when docetaxel was used at 0.2 microM and TAM at a dose equal to or higher than 1 microM. Flow cytometric DNA analysis performed on the three cell lines showed that TAM was able to increase the G2/M blocking activity of docetaxel. This blocking activity was followed by an increased flow cytometric DNA fragmentation suggestive of the presence of apoptosis, which was confirmed by DNA gel fragmentation and morphological analysis. While an antagonistic effect on P-glycoprotein (P-gp) activity may contribute to the synergistic effect of tamoxifen and docetaxel on CEM-VBLr and MCF-7 ADRr, other mechanisms must be involved, as the synergistic effect is also apparent with a P-gp-negative cell line.  相似文献   
10.
The literature shows an increasing number of works focused on investigating the behaviour of methods that uses concepts of control volumes in the solution of structural problems. In recent years, new approaches using unstructured meshes have been proposed, most of which addressing new applications and, to a lesser extent, the underling physical perspective. This paper presents a unified approach to the element‐based finite volume method and FEM‐Galerkin within the framework of the finite element space. Numerical examples highlight some accuracy issues associated with the element‐based finite volume method developed in this work. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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