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991.
This paper presents experimental results on the behavior in tension of reinforced concrete members strengthened with carbon fiber sheets (CFS). CFS reduced the crack spacing and brought about good crack width control as well as a significant change in the average bond stress and the average stress of steel reinforcing bars and concrete. The deterioration mechanism of the CFS bond properties near cracks was presented.  相似文献   
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993.
Hemodynamic parameters were measured during bathing and exercise testing in 43 patients with myocardial infarction (mean age: 60.2 years) to investigate the predictive parameters to determine when patients could safely resume bathing. Patients took a fresh water bath at 42 degrees C in the supine position for 5 min in a Hubbard tank. Group A showed an elevation of pulmonary capillary wedge pressure (PCWP) during bathing of 10 mmHg or more (23 patients, mean age: 61.7 years) and group B showed an elevation of less than 10 mmHg (20 patients, mean age: 60.5 years). Continuous multistep exercise tests were performed with a bicycle ergometer in the supine position, and hemodynamic parameters were measured at up to 50 W for 3 min on the day before the warm bathing test. There were no significant differences in the changes of arterial pressure and heart rate between the two groups. The PCWP at 3 min with a load of 50 W was significantly higher in group A (26.9 +/- 9.0 mmHg) than in group B (16.7 +/- 9.1 mmHg, p < 0.01). The stroke index (SI) during exercise testing was significantly lower in group A than in group B. The difference in the stroke index from baseline values (delta SI) at 3 min with a load of 50 W was significantly lower in group A (3.5 +/- 5.5 ml/m2/beat) than in group B (10.6 +/- 7.0 ml/m2/beat, p < 0.01). Similarly, delta CI and delta oxygen pulse during testing were significantly lower in group A than in group B. The physical work capacity and ejection fraction of the left ventricle of group A were significantly lower than those of group B, whereas the left ventricular end-diastolic pressure was higher in group A than in group B. CI, delta CI, SI, delta SI, METs, oxygen pulse, and delta oxygen pulse were examined by regression analysis and multivariate analysis to predict a significant elevation of delta PCWP during bathing. delta SI (p = 0.0032), delta CI (p = 0.0094), delta SI + METs (p = 0.0051), delta CI + METs (p = 0.0061), delta CI + delta SI (p = 0.0084), and delta CI + delta SI + METs (p = 0.0093) showed the highest correlations with delta PCWP. These findings suggest that changes in delta CI, delta SI, and METs are good predictive parameters for determining when patients may safely resume bathing. We suggest that patients with myocardial infarction, reduced cardiac function and a physical work capacity of approximately 4.0 METs, delta SI: 5 ml/m2/beat and delta CI: 2.4 l/min/m2 resume bathing only after careful consideration.  相似文献   
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996.
We have demonstrated previously that the GTP-binding protein gamma12 subunit is a selective substrate for phosphorylation by protein kinase C among various gamma subunits in vitro, and that a serine residue in the N-terminal region is involved. In the present study, we first determined that the site of phosphorylation was Ser1 with antibodies developed against two N-terminal peptides containing phosphorylated Ser1 and Ser2, respectively. Using an antibody recognizing phosphorylated gamma12 and Swiss 3T3 cells rich in this protein, gamma12 was found to be phosphorylated by stimulation of quiescent cells with various reagents, such as phorbol 12-myristate 13-acetate (PMA), NaF, fetal calf serum, lysophosphatidic acid, endothelin, and growth factors. Pertussis toxin completely and partially prevented phosphorylation of gamma12 induced by lysophosphatidic acid and fetal calf serum and by endothelin, respectively, suggesting a contribution of G(i/o). Phosphorylation of gamma12 was limited when cells were stimulated by a single reagent, even with PMA, a strong activator of protein kinase C, whereas simultaneous stimulation with lysophosphatidic acid and either PMA or platelet-derived growth factor induced a synergistic increase of phosphorylation, suggesting physiological roles for GTP-binding proteins and protein kinase C in combination. Phosphorylated gamma12 was also detected in various tissues of untreated rats. Its decrease by pertussis toxin treatment also suggested the involvement of G(i/o) in vivo.  相似文献   
997.
High crystalline quality thick GaN films were grown by vapor phase epitaxy using GaCl3 and NH3. The growth rate was in the range of 10~15 Μm/h. GaN films grown at higher temperatures (960~ 1020?C) were single crystalline with smooth surface morphologies. No chlorine impurity was incorporated in these films during growth. The best crystalline quality and surface morphology of grown films was achieved by sputtering a thin A1N buffer layer, prior to growth. According to reflection high energy electron diffraction and atomic force microscopy measurements, as-sputtered A1N buffer layer was amorphous with root means square roughness of 0.395 nm and then crystallized during the GaN growth. This improved the GaN growth due to more uniform distribution of GaN nucleation. Rutherford backscattering channeling experiments produced the lowest value from the GaN film grown on a-Al2O3 with a 500å A1N buffer layer at 1020?C.  相似文献   
998.
OBJECTIVE: To study the effects of clomiphene citrate (CC) on the endometrium by ultrasound and to reveal the echogenic difference between the control cycle and the CC cycle. DESIGN: Retrospective study of patients before and during a CC treatment. SETTING: Department of Obstetrics and Gynecology, Yamaguchi University School of Medicine, Ube, Yamaguchi, Japan. PATIENT(s): Seventy-nine infertile women who had a spontaneous ovulation and a normal luteal function. INTERVENTION(s): Patients received 50 mg/d CC between days 5 and 9 of the menstrual cycle. MAIN OUTCOME MEASURE(s): Endometrial thickness, echogenic pattern of the endometrium, serum E2 content, and E2 and P receptor contents in the endometrium. RESULT(s): Endometrial thickness was significantly thinner during the CC cycle (7.6 +/- 1.4 mm, mean +/- SD, n = 79) than during the control cycle (8.5 +/- 1.7 mm, n = 79) on late proliferative days, but there was no significant difference on midsecretory days (10.8 +/- 2.2 mm during the CC cycle, n = 79; 11.2 +/- 2.2 mm during the control cycle, n = 79). The echogenic patterns, however, were different between the two cycles on midsecretory days. Moreover, the incidence in which patients showed a grade 3 endometrium on midsecretory days was significantly higher during the conceived CC cycle compared with the not-conceived CC cycle. Serum E2 levels were significantly higher, but E2 receptor contents in the endometrium were significantly lower during the CC cycle (67 +/- 46 fmol/mg, n = 13) compared with the control cycle (123 +/- 89 fmol/mg, n = 15) on late proliferative days. CONCLUSION(s): Clomiphene citrate affected the echogenic pattern of the endometrium, and most of the endometrium showed a grade 3 pattern on midsecretory days during the conceived CC cycle. Under the CC treatment, the comfortable endometrium for embryos might be different from the control cycle.  相似文献   
999.
A 64-bit carry look ahead adder using pass transistor BiCMOS gates   总被引:1,自引:0,他引:1  
This paper describes a 64-bit two-stage carry look ahead adder utilizing pass transistor BiCMOS gate. The new pass transistor BiCMOS gate has a smaller intrinsic delay time than conventional BiCMOS gates. Furthermore, this gate has a rail-to-rail output voltage. Therefore the next gate does not have a large degradation of its driving capability. The exclusive OR and NOR gate using the pass transistor BiCMOS gate shows a speed advantage over CMOS gates under a wide variance in load capacitance. The pass transistor BiCMOS gates were applied to full adders, carry path circuits, and carry select circuits. In consequence, a 64-bit two-stage carry look ahead adder was fabricated using a 0.5 μm BiCMOS process with single polysilicon and double-metal interconnections. A critical path delay time of 3.5 ns was observed at a supply voltage of 3.3 V. This is 25% better than the result of the adder circuit using CMOS technology. Even at the supply voltage of 2.0 V, this adder is faster than the CMOS adder  相似文献   
1000.
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