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101.
We report a case of generalized peritonitis caused by spontaneous intraperitoneal rupture of the urinary bladder. A 74-year-old female was admitted with abdominal pain and biochemical findings of acute renal failure (ARF). She had recently complained of macrohematuria. She had a past history of radiotherapy for uterine cervical cancer and Parkinson's disease treated with levodopa and amantadine. We diagnosed this case as intraperitoneal rupture of the bladder by cystogram. Biochemical findings of ARF might have resulted from urine reabsorption. Intraperitoneal rupture of the bladder should be considered in all cases of peritonitis, especially in patients with urological symptoms and features of ARF.  相似文献   
102.
A retrospective chart review of 43 patients who underwent technetium 99m (Tc-99m) sestamibi scans from June 1995 to January 1997 was performed. Only those who underwent subsequent parathyroid exploration with excision were included in the study. Twenty subjects (13 women and seven men) were included in the study. Ages ranged from 21 to 84 years (mean, 58 years). All patients had laboratory values and clinical findings consistent with primary hyperparathyroidism. Two patients had preoperative magnetic resonance imaging (MRI) scans (one patient with recurrent disease), and one had a preoperative computed tomography (CT) scan. The remaining patients had the sestamibi scan as the only preoperative localization study. There were 18 pathologic diagnoses of parathyroid adenoma and two of parathyroid hyperplasia. Sestamibi failed to correctly identify the location of the parathyroid lesion in two cases. In 18 cases the preoperative sestamibi scan correctly localized the lesion, a predictive value of 90%. We conclude that the Tc-99m sestamibi scan is an accurate preoperative tool that can be used as a single modality to localize parathyroid adenomas.  相似文献   
103.
Results of gain measurements on an AlGaAs laser amplifier with an optical isolator are reported. The maximum net gain was 25 dB when input power was less than ?40 dBm. By measuring internal loss, a saturation parameter was estimated to be 6 mW.  相似文献   
104.
105.
Summary Graft copolymers of end methacrylate-functionalized[MacroAM] or styrene-functionalized[MacroAS] polyamide macromonomers with methyl methacrylate(MMA) were prepared by radical copolymerization, and their thermal, dynamic properties, and miscibility with matrix PMMA have been investigated. The glass transition temperature(Tg)s of the copolymers were significantly elevated with the increase of the macromonomer content in the copolymer. Storage modulus E of the graft copolymers began to decrease at around 85°C, which is close to Tg of PMMA, irrespective of the macromonomer content in the copolymers. As the macromonomer content and its degree of polymerization became higher, the drop in E became significant.  相似文献   
106.
Pose estimation is one of the important tasks for mobile robots exploring in outdoor environments. Recently, visual odometry has received a lot of attention since its localization is accurate even with low-cost sensors. Furthermore, the technique is not affected by wheel slips, and it can be performed without external infrastructures and preliminary maps. While existing techniques successfully provide good localization of outdoor vehicles, possible failures are not yet fully examined in untextured terrains where feature tracking occasionally fails. This paper proposes an approach to detect interest points from a wide variety of terrains by adaptively selecting algorithms. Experiments show that the approach provides robust and fast interest point detection even in untextured natural scenes.  相似文献   
107.
108.
This paper presents terrain mapping and path‐planning techniques that are key issues for autonomous mobility of a planetary exploration rover. In this work, a LIDAR (light detection and ranging) sensor is used to obtain geometric information on the terrain. A point cloud of the terrain feature provided from the LIDAR sensor is usually converted to a digital elevation map. A sector‐shaped reference grid for the conversion process is proposed in this paper, resulting in an elevation map with cylindrical coordinates termed as C2DEM. This conversion approach achieves a range‐dependent resolution for the terrain mapping: a detailed terrain representation near the rover and a sparse representation far from the rover. The path planning utilizes a cost function composed of terrain inclination, terrain roughness, and path length indices, each of which is subject to a weighting factor. The multipath planning developed in this paper first explores possible sets of weighting factors and generates multiple candidate paths. The most feasible path is then determined by a comparative evaluation between the candidate paths. Field experiments with a rover prototype at a Lunar/Martian analog site were performed to confirm the feasibility of the proposed techniques, including the range‐dependent terrain mapping with C2DEM and the multipath‐planning method.  相似文献   
109.
The improvement of toughness and heat resistance of phenolic resin was examined by blend of novolac and copolymers prepared from p-hydroxyphenylmaleimide (HPMI) and acrylic ester. Copolymers of HPMI and acrylic esters, such as methyl acrylate, ethylacrylate, n-butylacrylate, or 2-ethylhexyl acrylate, were synthesized. Average molecular weights, glass transition temperatures (Tg) and thermal decomposition temperatures were measured. The miscibility of the copolymers with novolac was evaluated. It was found that these copolymers had higher average molecular weight and higher thermal decomposition temperature than those of novolac; they also had good miscibility with novolac. Molding compounds were prepared by hot roll-kneading of mixtures, which involved novolac, the copolymer, hexamethylenetetramine (hexamine), and glass fiber. Test pieces of the modified phenolic resins were prepared by transfer molding from the molding compounds. It was found that phenolic resin, modified with HPMI/ethylacrylate copolymer or HPMI/n-butylacrylate copolymer, which consisted of numerous units of acrylic ester, showed both good toughness and good heat resistance.  相似文献   
110.
Diesel spray is injected at high pressure. So, upper stream region of spray is high Weber number condition. However, even if the fuel is injected at high pressure, the downstream region of spray is corresponding to relatively low Weber number condition. Thus, KH (Kelvin-Helmholtz) model modeled for high Weber number conditions and MTAB (modified Taylor analogy breakup) model are used for primary and secondary breakup processes respectively. This study is focused on the development of new hybrid breakup model The calculations are performed by LES (large eddy simulation) incorporated into KIVA code. LES of non-evaporating diesel spray are performed using KH & RT (Rayleigh-Taylor) model, MTAB model and KH-MTAB model. Then, LES with these models were compared with experimental results. As the result, the availability of KH-MTAB model is showed. It is found that KH-MTAB is good agreement with experimental results of penetration and SMD (Sauter mean diameter) in relatively low density conditions.  相似文献   
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