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31.
Transjugular intrahepatic portosystemic shunt (TIPS) is a side-to-side portocaval shunt for threatening complications of portal hypertension. The purpose of this study was to evaluate in first 33 patients indicated for TIPS insertion in our institution the efficacy, complications, and mortality. Indication was failure of sclerotherapy or ligation in control either of acute (n = 4) or repetitive (n = 25) variceal bleeding and refractory ascites (n = 4). The technical success rate was with 70% (21/30) lower than expected, but the complication rate was also very low. There were no fatal complications, only one subcapsular liver hematome, and in one patient repetitive punction of biliary tract. The 30-days mortality was 10% (2/21) and rebleeding was 15% (3/20), caused always by thrombosis of the shunt. TIPS seems to be a promising therapeutic procedure after failed endoscopic therapy of esophageal varices without the mortality and morbidity of an open surgical procedure. Recent indications for TIPS are acute variceal hemorrhage refractory to endoscopic treatment and recurrent variceal bleeding despite sclerotherapy or band ligation. Promising seems to be TIPS insertion in the treatment of refractory ascites. 相似文献
32.
Hydrogenated amorphous silicon oxygen alloy thin films (a-SiOx:H) were prepared on glass and crystalline silicon substrates, with two different oxygen contents: x = 0.15 and x = 0.32. The deposition was realized in an RF-PECVD reactor by using the plasma of the gas mixture SiH4 and CO2 with tunable flow rates. The optical characterization data of the single layers were received from the optical transmittance experiments. Multilayered samples were designed upon the results of the single layers. In depositing the multilayers the repetition of the a-SiO0.15:H/a-SiO0.32:H kernel-pair was used. The samples were prepared as 25-pair of λ/4 layers, 3-pair of λ/4 layers and 3-pair of λ/2 layers. The inner morphologies and nanostructural contents of the films were investigated by Small-Angle X-ray Scattering (SAXS) method. 相似文献
33.
In this paper, we present a generalized Fourier series based algorithm for the identification of continuous‐time, linear‐time invariant systems from power spectrum measurements. The algorithm is strongly consistent and it is used in the design of a linear shaping filter for a single‐track road power spectrum. 相似文献
34.
B. Uyulgan E. Dokumaci E. Celik I. Kayatekin N.F. Ak Azem I. Ozdemir M. Toparli 《Journal of Materials Processing Technology》2007,190(1-3):204-210
The principle aim of this study is to investigate the wear behaviour of FeCr coatings on Ni-based bond deposited plain carbon steel substrate for several applications in power generation plants. For this purpose, FeCr and Ni-based powders were sprayed on plain carbon steel substrates using a thermal flame spray technique. Fabricated layers were characterized by using a X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), microhardness and surface roughness testers. FeCr coatings were subjected to sliding wear against AISI 303 stainless steel counter bodies under dry and acidic environments. A pin-on-plate type of apparatus was used with normal loads of 49 and 101 N and sliding speed of 1 Hz. XRD results revealed that FeCr, Fe, Cr, Fe–Cr–Ni, γ-Fe2O3 and Fe3O4 phases are exist in the coating. In addition, some inhomogenities such as oxides, porosity, cracks, unmelted particles and inclusions were observed by SEM. The surface morphologies of FeCr samples after wear experiments were examined by SEM and EDS. It was found that friction coefficients of the coatings in dry condition are higher than that in acidic environment. 相似文献
35.
36.
Salwan K. J. Al-Ani Raid A. Ismail Hana F. A. Al-Ta’ay 《Journal of Materials Science: Materials in Electronics》2006,17(10):819-824
Optoelectronic properties of CdS:In/Si anisotype heterojunction photodetector fabricated by depositing of polycrystalline
CdS and indium doped CdS films used thermal resistive technique on clean monocrystalline p-type silicon substrates are presented. The effect of In diffusion
temperature(T
d)in CdS layer on the optoelectronic characteristics of these devices has been studied. Two peaks situated at 650 and 800 nm
with values of 0.32 and 0.43 A/W, respectively, were observed in the responsivity plot. Other optoelectronics properties such
as detectivity, photovoltaic, and response time are also presented. 相似文献
37.
38.
The techniques used in the cooling of electronic equipments vary widely depending on the particular application. Cooling with liquids and impinging air jets become important where classical cooling techniques may be insufficient, while a single or array jet is employed where highly localised cooling is desired. This paper provides a comparative survey of advanced methods of cooling for electronic systems and an economical analysis of cooling electronic equipments using slot and circular jets. 相似文献
39.
MM Ba?ar MF Sargon H Ba?ar A Atan F Ak HH Celik R Ba?ar Z Akalin 《Canadian Metallurgical Quarterly》1998,5(3):252-255
BACKGROUND/AIMS: The colonic response to obstruction is poorly understood. Thickening of the proximal bowel following colonic stricture may be due to increased protein synthesis. We have investigated the colonic morphology and collagen concentration during the development of left-sided colonic obstruction in an animal model. METHODS: Twelve male Wistar rats received either a silk ligature obstruction of the colon 2.5 cm above the peritoneal reflection (n = 6) or manipulation of the left colon (controls, n = 6). Twenty-four hours later, three colonic specimens from the ligature zone and from 1 cm proximal and distal to this site, or from equivalent regions in controls, were assayed for hydroxyproline concentration. RESULTS: In controls there was no difference in hydroxyproline concentration between colonic sites. In obstructed rats, the hydroxyproline concentration was greater both at the ligature and distally, when compared with the proximal region. The hydroxyproline concentration was higher (p < 0.05) than corresponding control values at the ligature site (14.95 +/- 2.76 vs. 10.97 +/- 1.95 microgram/mg of dry tissue mean +/- s.d.) but not on either side. CONCLUSION: The colonic collagen concentration is equivalent or raised near an obstruction, demonstrating that obstructed colon may possess an enhanced capacity to hold sutures. 相似文献
40.
This paper analyses emergency tasks within the theoretical framework of dynamic environment management with distributed decision-making (DDM). Models of task and work organization are used to analyse verbal exchanges in order to infer collective strategies. A cross-analysis method serves to analyse communication from the standpoint of both semantics and structure of the exchanges. The findings of two empirical comparative studies show that invariants vs differences in the organization and the semantics of exchanges are associated with invariants vs differences in parameters of the situations themselves (initial state and final result of actions). Efficient strategies were linked with well-structured flow of communication and roles distribution. 相似文献