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81.
BACKGROUND AND PURPOSE: Our objective was to find the specific angiographic characteristics of atherosclerotic lesions that indicate suitability for intracranial percutaneous transluminal cerebral balloon angioplasty (PTCBA). METHODS: Forty-two clinically symptomatic patients with 42 hemodynamically significant intracranial lesions (>70% stenosis) were treated by PTCBA between January 1992 and May 1996. Before treatment, the patients were assigned to three groups according to the angiographic characteristics of the lesions, as follows: type A, short (5 mm or less in length) concentric or moderately eccentric lesions less than totally occlusive; type B, tubular (5 to 10 mm in length), extremely eccentric or totally occluded lesions, less than 3 months old; and type C, diffuse (more than 10 mm in length), extremely angulated (>90 degrees) lesions with excessive tortuosity of the proximal segment, or totally occluded lesions, and 3 months old or older. The patients were followed up for a period of 1 month to 6 years to compare the results of PTCBA treatment among the three groups. Primary end points were death, stroke, or bypass surgery. RESULTS: The clinical success rates for the type A, B, and C groups were 92%, 86%, and 33%, respectively. Cumulative risks of fatal or nonfatal ischemic stroke or ipsilateral bypass surgery in type A, B, and C groups were 8%, 26%, and 87%, respectively. The cumulative risk of 8% among patients in the type A group appeared to be smaller than in studies reported in the literature. CONCLUSION: PTCBA for intracranial simple (type A) lesions yields a favorable clinical outcome for symptomatic patients.  相似文献   
82.
The bimetallic catalysts prepared from Ir4Fe and Pd6Fe6 carbonyl clusters exhibited high activities and selectivities towards methanol from CO + H2. In contrast, hydrocarbons and CO2 were preferentially obtained on the catalyst prepared from Fe-rich PdFe4 cluster. The promotion towards methanol synthesis on the SiO2-supported Ir4Fe and Pd6Fe6 cluster catalysts was proposed to be associated with Pd-Fe3+ and Ir-Fe3+ sites located at the metal-support interface.  相似文献   
83.
STUDY DESIGN: Subacute compression of the spinal cord was applied to rats. The animals were chronologically observed using magnetic resonance imaging for more than 8 weeks after surgery and were killed for histopathologic examination. OBJECTIVES: To investigate the correlation of changes in signal intensity on magnetic resonance images with those observed in histopathologic study and with the degree of spinal cord compression and paralysis. SUMMARY OF BACKGROUND DATA: No consensus has been reached concerning the correlation of magnetic resonance images to clinical symptoms of compressive myelopathy. Few reports are available in which magnetic resonance imaging findings are compared with histopathologic features in chronic or subacute experiments. METHODS: In rats under general anesthesia, the T11 lamina was thinned and a slow increase in volume was applied. Hind limb paralysis appeared 1 week after the procedure and spontaneously subsided thereafter. The degree of spinal compression and signal intensity was observed chronologically using magnetic resonance imaging. The signal intensity on the final MR images was rated on a four-point scale and compared with histopathologic findings. RESULTS: As spinal compression increased, the incidence of high signal intensity on long spin-echo images became higher. Low signal intensities on short spin-echo images were visible in animals in which compression and paralysis were the most severe. In these animals, cavitation and a dilated central canal were visible. High signal intensities on long spin-echo images reflected various pathologic changes. CONCLUSIONS: Changes in signal intensity on MR images are visible after the induction of myelopathy by high-pressure compression. These signal intensities may be useful in predicting the outcome of compressive myelopathy.  相似文献   
84.
A 50-year-old man with Churg-Strauss syndrome showed granulocytes (GNLs) which generated more superoxide anion (O2-) than GNLs from healthy subjects following in vitro stimulation with C5a or C3a. Production of O2- subsided as the clinical symptoms improved with steroid treatment. A hyperresponsiveness of GNLs may be involved in this disorder.  相似文献   
85.
A suspended patch antenna electromagnetically excited by an inverted microstrip line has been studied based on a full-wave transmission line analysis in conjunction with a microwave network theory. The input impedance calculated has been compared with measured data.  相似文献   
86.
Thallium-201 chloride (201TlCl) single photon emission computed tomography (SPECT) was used to determine tumor viability, and the early and delayed images of technetium-99m-diethylenetriaminepenta-acetic acid-human serum albumin (99mTc-HSA-D) SPECT were used to assess tumor vascularity and permeability, respectively, in 17 patients with 18 brain metastases. SPECT was performed before, 1 week after, and 1 month after radiosurgery. The ratios of 201Tl and 99mTc-HSA-D uptake in a tumor were expressed as a ratio to uptake in the corresponding normal contralateral areas (uptake index). Magnetic resonance imaging with gadolinium was used to determine tumor volume. 201Tl index decreased significantly 1 week (p < 0.05) and 1 month (p < 0.005) after radiosurgery. In contrast, 99mTc-HSA-D indices of early and delayed images obtained at 1 week after radiosurgery were not significantly different from the pretreatment values. However, both were significantly low (p < 0.05) 1 month after radiosurgery. No change in tumor volume was detected 1 week following radiosurgery, but there was a significant decrease (p < 0.005) after 1 month. The reduction in tumor viability that occurs before the appearance of evidence of tumor shrinkage represents the early effect of radiosurgery on brain metastases. Reduction in tumor size, vascularity, and permeability occur subsequently.  相似文献   
87.
An ultrasonic on-line system to measurer values in cold rolled steel sheets has been developed with electromagnetic acoustic transducers (EMATs). These EMATs are composed of meanderline coils and electromagnets and operate with the magnetostrictive mechanism. The EMAT instrument measures the propagation times of the fundamental symmetrical Lamb (S o ) wave at a low frequency and relates them to ther values through a calibrated regression curve. Preliminary tests indicate that the on-line monitoring ofr is quite feasible with a standard deviation of 0.07 for various low carbon steel sheets; the thicknesses range from 0.5 mm to 2.5 mm. The measuring time is 20 msec per data. The liftoff is allowed to 5 mm with 2 mm thick sheet. Ther evaluation is independent of the line speed up to 325 m/min. These promising results promote installation of ultrasonicr-value measurement systems in steel production lines.  相似文献   
88.
In this paper, a newly proposed vertically installed planar circuits are described. This circuits were developed for the purpose to make low cost microwave circuit in mass production. As examples, 3 dB-directional coupler and filters are described together with their applications.  相似文献   
89.
We have reported our "new questionnaire of QOL (quality of life) in anti-emetic therapies during cancer chemotherapy" and demonstrated its reliability and validity. In the present study we investigated the utility of tropisetron capsules for delayed nausea and vomiting induced by cancer chemotherapies with CDDP single administration in a placebo-controlled double-blind comparative study using the questionnaire. The questionnaire was composed of the following scales: a physiological scale (appetite, feeling, vomiting, nausea), a psychological scale (sleep, mental fatigue, anxiety, pain, abdominal condition), a respiratory condition related scale (sputum, respiratory distress), an active scale (daily life in a hospital), a social relation scale (understanding of the family), a linear analogue scale for evaluation of the influence of nausea and vomiting in patient's life during 24 hours, and a face scale as the global scale. First, all patients were administered a preventive dose of tropisetron capsule on day 1 (the day of CDDP administration) and then allotted to once-daily oral administration of either a tropisetron (T group) or a placebo (P group) capsule during days 2 to 5 by a double-blind method. Chronological changes of QOL during the study period were measured by the area under the curve (AUC) generally used for calculation of blood levels of drugs. The maximum fluctuation (Difmax) of QOL scores throughout the whole study period was also evaluated. The data were collected from 114 cases, and 98 cases (51 in P group, 47 in T group) were analyzed. 1) The total score or 13 items (a modified linear analogue scale with 5 graduations), the face scale and linear analogue scale of T group were higher (better) than those of P group. 2) As for the total score of each scale, the physiological, psychological and active scales in the T group showed higher (better) levels than the P group. 3) As for the AUC values, the T group was lower (better) than the P group in most items. In AUC of the total score of 13 items, the face scale, the physiological and the psychological scales, the T group was significantly superior to the P group. 4) AUC levels of each item belonged to the physiological and the psychological scales in the T group tended to be lower (better) than the P group, and "sleep" and "pain" in the psychological scale were significantly lower (better) in T group than P group. 5) In Difmax values, all scales except respiratory condition related scale showed lower levels (better) in T group and the total score of 13 items, the face scale and the physiological and psychological scales showed significantly lower levels than P group. 6) Difmax values in each item belonging to the physiological and psychological scales showed lower levels in the T group, while "appetite" and "vomiting" in the physiological scale and "sleep" in the psychological scale showed significantly lower levels (better) than those of the P group. 7) In the stratified analysis performed for patients without nausea and vomiting on the 1st day of chemotherapy, there was no significance in AUC levels of all items in both groups. In patients with nausea and vomiting on the 1st day, the total score of 13 items, the face scale, the physiological and the psychological scales in the T group were significantly better than in the P group. 8) It was suggested that the anti-emetic efficacy of tropisetron for delayed nausea and vomiting might reduce the undesirable influence of chemotherapy on QOL, especially on the physiological and the psychological effects. These results suggested that this new questionnaire is applicable for evaluation of the utility of anti-emetics in patients in cancer chemotherapy, and that tropisetron capsules could reduce the decrease of QOL in delayed nausea and vomiting induced by chemotherapy.  相似文献   
90.
NaY zeolite-encapsulated iron phthalocyanine (FePc) was synthesized from [HFe3(CO)11] in NaY. The structural properties of FePc in NaY were studied by EXAFS, Mössbauer, FT-IR, and diffuse reflectance UV-VIS. The spectroscopic results suggest that NaY-encapsulated FePc (FePc/NaY) is slightly distorted from the original planar structure of a phthalocyanine molecule due to the intrazeolitic constraint. Electron donor-acceptor (EDA) complex (Na+)4(FePc4–)/NaY was prepared from FePc/NaY by the reaction with sodium-naphthalene (Na+)(C10H 8 ). They gave a higher trans/cis ratio of 2-butenes in butadiene hydrogenation compared with the EDA complex on the external surface of NaY.  相似文献   
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