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941.
In this retrospective study, we examined 35 adult patients with biopsy-proven, primary focal and segmental glomerulosclerosis (FSGS) and nephrotic syndrome to determine whether any of the clinical and morphological features of FSGS were associated with a higher risk of a poor renal outcome. Clinical factors assessed were the age, sex, amount of urinary protein, and presence of microscopic hematuria, hypertension and renal dysfunction at onset in each patient. Morphological parameters included the number of segmental sclerosis and global sclerosis, sclerosis score, location of segmental sclerosis, mean glomerular diameter, grade of tubulo-interstitial changes, and presence of vascular lesions. Twenty-three patients (66%) were in complete or incomplete (partial) remission, and 12 (34%) were non-responders at the end of follow-up. On univariate analysis, the age at onset, sclerosis score, mean glomerular diameter, and grade of tubulo-interstitial changes in no response were significantly greater than those parameters in remission. Multivariate logistic regression analysis revealed that the degree of tubulo-interstitial changes and mean glomerular diameter were independent risk factors for a poor renal outcome. These findings suggest that the estimation of these latter two parameters allows the nephrologist to predict the probable course and prognosis of an adult with FSGS. Intensive and prolonged therapy is recommended for patients without these two morphological features.  相似文献   
942.
943.
944.
Twelve porcine liver transplantations were performed to investigate whether serum hyaluronic acid (HA) serves as a marker of warm ischemic injury. Group 1 was a control without warm ischemia (n = 7), and pigs in Group 2 were sacrificed by intracardiac KCl injection 60 min before harvesting (n = 5). All pigs survived more than 4 days in Group 1. In Group 2, all died within 2 days due to graft failure. Arterial and hepatic venous glutamic-oxaloacetic transaminase (GOT) in Group 2 were higher after revascularization. However, there were no differences between the 2 groups in arterial and hepatic venous HA levels. HA clearance by the graft also showed no differences between the groups. Although GOT reflected the degree of warm ischemia, HA and its hepatic clearance were not influenced by warm ischemic damage. In conclusion, HA was not thought to serve as a marker of liver injury when the graft suffered from warm ischemia.  相似文献   
945.
Nuclear radiation detectors with Josephson junctions, as hitherto reported, were composed of thin superconducting strips and had a poor energy resolution. A conceptual study is made on improvement of these detectors, with special consideration of quasiparticle collection. A bulk superconductor is shown to be appropriate as a radiation detector. Superconducting tunnel junctions of two types are proposed for superconducting radiation detectors of excellent energy resolution. These have high barrier penetrability and large area in order to collect all the quasiparticles generated in the superconductor by nuclear radiation.  相似文献   
946.
Increasing attention has been given to pollution of the water environment by pharmaceutical compounds discharged from wastewater treatment plants. High-pressure driven membranes such as a nanofiltration (NF) membrane and a reverse osmosis (RO) membrane are considered to be effective for control of pharmaceuticals in wastewater treatment. In practical applications of NF/RO membranes to municipal wastewater treatment, feed water for the membranes always contains organic macromolecules at concentrations of up to 10 mg-TOC/L, which are mainly composed of soluble microbial products (SMPs) produced during biological wastewater treatment such as an activated sludge process. In this study, influence of these organic macromolecules on removal of six pharmaceuticals by NF/RO membranes (UTC-60 and LF10) was investigated. Two types of biological treatment (conventional activated sludge process followed by media filtration (i.e., tertiary treatment) and treatment with a membrane bioreactor (MBR)) were examined as pretreatments for NF/RO membranes in this study. In the filtration tests with wastewater effluents, removal of the pharmaceuticals was higher than that seen with deionized pure water spiked with the pharmaceuticals. The increase was significant in the case of the NF membrane. Both alteration of membrane surface properties due to membrane fouling and association of the pharmaceuticals with organic macromolecules contributed to the increase in removal of pharmaceuticals by the membranes. Characteristics of the organic macromolecules contained in the wastewater effluents differed depending on the type of treatment, implying that removal of pharmaceuticals by NF/RO membranes is influenced by the type of pretreatment employed.  相似文献   
947.
Metallurgical and Materials Transactions A - Grain boundary segregation in iron-sulfur-carbon alloys containing up to 100 wt ppm sulfur and up to 90 wt ppm carbon has been investigated with Auger...  相似文献   
948.
Abstract: The aim of this paper is to focus on special items of research and development (R&D) areas in which Taisei Corporation is active, to discuss some of the issues involved in automation research and the importance of information management in automation and robotics, and to delve into the possible future of construction robotics and automation. In the first section we break automation and robotics down into four levels: simple mechanization, robots, mechanized construction systems, and fully automated construction. Each is discussed separately and, with the exception of fully automated construction, examples of R&D in each category are described. This gives the reader a glimpse of what a general contractor in Japan is currently doing. In the second section we describe information-integrated construction (IIC), which can be defined as the use of computer technology to collect, store, manipulate, enhance, and display construction information and expertise as a way to streamline the construction process.  相似文献   
949.
We developed a portable needle-probe videomicroscope with a charge-coupled device (CCD) camera to visualize the subendocardial microcirculation. In 12 open-chest anesthetized pigs, the sheathed needle probe with a doughnut-shaped balloon and a microtube for flushing away the intervening blood was introduced into the left ventricle through an incision in the left atrial appendage via the mitral valve. Images of the subendocardial microcirculation of the beating heart magnified by 200 or 400 on a 15-in. monitor were obtained. The phasic diameter change in subendocardial arterioles during cardiac cycle was from 114 +/- 46 microns (mean +/- SD) in end diastole to 84 +/- 26 microns in end systole (p < 0.001, n = 13, ratio of change = 24%) and that in venules from 134 +/- 60 microns to 109 +/- 45 microns (p < 0.001, n = 15, ratio of change = 17%). In contrast, the diameter of subepicardial arterioles was almost unchanged (2% decrease, n = 5, p < 0.01), and the venular diameter increased by 19% (n = 8, p < 0.001) from end diastole to end systole. Partial kinking and/or pinching of vessels was observed in some segments of subendocardial arterioles and venules. The percentage of systolic decrease in the diameter from diastole in the larger (> 100 microns) subendocardial arterioles and venules was greater than smaller (50-100 microns) vessels (both p < 0.05). In conclusion, using a newly developed microscope system, we were able to observe the subendocardial vessels in diastole and systole.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
950.
A DC-60 GHz, 9 dB distributed amplifier IC module is fabricated with 0.15 μm InAlAs-InGaAs low-noise HEMTs with 155 GHz fT and 234 GHz fmax. The device is mounted in a metal package with 1.8 mm coaxial cable signal interfaces. The package is specially designed using three-dimensional electromagnetic field analyses, resulting in very flat frequency characteristics of the module within 1.5 dB gain ripples over the entire bandwidth. A multichip module loaded with two amplifier ICs in cascade is also fabricated, and operates at a 17.5 dB gain from 60 kHz to 48 GHz. The 1 dB gain compression output power is about 5 dBm for both modules. The noise figure of the single-chip module is approximately 4 dB over a 10-40 GHz frequency range  相似文献   
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