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141.
TL Ott JG Fleming TE Spencer MM Joyce P Chen CN Green D Zhu TH Welsh PG Harms FW Bazer 《Canadian Metallurgical Quarterly》1997,57(3):621-629
Interferon tau (IFN tau) is the conceptus-produced antiluteolytic signal in ruminants. Three experiments examined the effects of s.c. administration of recombinant ovine (ro)IFN tau on interestrous interval (IEI), oxytocin (OT)-induced uterine prostaglandin F2alpha metabolite (PGFM) production, rectal temperature (RT), respiration rate (RR), and plasma concentrations of progesterone, cortisol, LH, and antiviral activity (AVA) in plasma and uterine flushings. In experiment I, 20 ewes were treated s.c. with either 0, 1, 2, or 4 mg/day roIFN tau (0.7 x 10(8) U/mg; 5 ewes/dosage) from Days 11 to 15 of the estrous cycle (estrus = Day 0) and were challenged with OT (30 IU) on Day 15. Jugular blood samples were collected at -10, 0, 10, 20, 30, 40, 50, and 60 min relative to the OT challenge and assayed for PGFM. Recombinant oIFN tau increased IEI (16.7, 18.7, and 22.6 +/- 0.6 days for 0, 2, and 4 mg roIFN tau, respectively, p < 0.01). Recombinant oIFN tau did not affect peak PGFM response to OT (2309 +/- 172 pg/ml; p > 0.1). However, the 4 mg/day dosage delayed the time to peak PGFM (32.4 vs. 47.5 +/- 3.4 min; p < 0.01, 0 vs. 4 mg) and resulted in approximately 200% higher concentrations of PGFM at 60 min post-OT (0 vs. 4 mg/day, p < 0.07). Experiment II was similar to experiment I, except that only the 0- and 4-mg/day dosages of roIFN tau were administered. Ewes were hysterectomized on Day 16, and assay of uterine flushes detected no AVA from ewes treated with either 0 or 4 mg/day roIFN tau. In experiment III, 20 ewes were treated s.c. with either 0, 2, 4, or 6 mg roIFN tau on Day 12. Blood samples, RT, and RR were obtained at frequent intervals for 24 h, and plasma was assayed for progesterone, cortisol, LH, and AVA. Plasma AVA, which increased in a dose-dependent manner, was detectable within 60 min and remained elevated at 24 h compared to control values. RT (elevated 0.5-1.0 degrees C), RR, and cortisol increased in response to all dosages of roIFN tau, with peak values occurring 150-180 min postinjection. For all dosages of roIFN tau, plasma progesterone declined from 120 to 360 min posttreatment and then returned to pretreatment values by 24 h (p < 0.01) as compared to controls. Overall, exogenous roIFN tau altered uterine PGFM response to OT from a pulse to a gradual and sustained elevation and extended IEI with only a transient decline in progesterone and mild hyperthermia, effects that are not expected to compromise pregnancy. 相似文献
142.
JM Martínez Jabaloyas S Sanz Chinesta JF Jiménez Cruz N Flores Corral M Unda Urzaiz O Leiva Galvis V González Romojaro C Hernández Fernández E Lledó García LA Rioja Sanz A Gonzalvo Ibarra JE Camacho González F Ruíz Alvárez-Cienfuegos L Resel Estévez J Corral Saleta R Burgos Rodríguez JM Del Rosal Samaniego 《Canadian Metallurgical Quarterly》1997,21(7):668-674
Prospective, randomized, multicenter study in 267 patients with complicated urinary infection from 9 hospitals nationwide. Drug treatment was either Ceftriaxone 1 g once daily parenterally or Cefotaxime parenteral 1 g 8 hourly for a minimum of 7 days. Patients were clinically, analytically and microbiologically evaluated before and after treatment to assess the efficacy and tolerance of both drug products. To evaluate treatment cost, we used the price of both drugs and the material required for their administration (syringe and disposable needle). 119 patients were excluded from the cost-efficacy evaluation and 148 remained in the study (75 assigned to treatment with Ceftriaxone and 73 to Cefotaxime). Clinical efficacy of treatment was 93% and 87.6% for Ceftriaxone and Cefotaxime respectively (p > 0.05). Cost per patient was 27,347 pesetas for Ceftriaxone and 34,490 for Cefotaxime (p < 0.05). 相似文献
143.
Fang Zheng Peng Ott G.W. Jr. Adams D.J. 《Power Electronics, IEEE Transactions on》1998,13(6):1174-1181
This paper presents harmonic and reactive power compensation based on a generalized theory of instantaneous reactive power for three-phase power systems. This new theory gives a generalized definition of instantaneous reactive power, which is valid for sinusoidal or nonsinusoidal and balanced or unbalanced three-phase power systems with or without zero-sequence currents and/or voltages. The properties and physical meanings of the newly defined instantaneous reactive power are discussed in detail. A harmonic and reactive power compensator based on the new theory for a three-phase harmonic-distorted power system with zero-sequence components in the load current and/or source voltage is then used as an example to show harmonic and reactive power measurement and compensation using the new theory. Simulation and experimental results are presented 相似文献
144.
MD Keiper RI Grossman JA Hirsch L Bolinger IL Ott LJ Mannon CP Langlotz DL Kolson 《Canadian Metallurgical Quarterly》1998,19(8):1489-1493
BACKGROUND AND PURPOSE: Although MR spectroscopy and functional MR imaging of the brain have been successful at 4 T, conventional fast spin-echo imaging of the brain at 4 T has not been adequately evaluated. The purpose of this study was to compare the detection of white matter abnormalities in multiple sclerosis (MS) at 1.5 T and 4 T. METHODS: Fifteen patients with clinically definite MS were imaged at both 1.5 T and 4 T within a 1-week period. Comparison was made between fast spin-echo long-TR images at both field strengths. Pulse sequences were tailored to maximize resolution and signal-to-noise ratio in clinically relevant imaging times (< 7 min). Four interpreters independently reviewed the images obtained at both field strengths in separate sessions and evaluated them for lesion identification, size, characterization, and subjective resolution. Differences in interpretations at 1.5 T and 4 T were subsequently recorded. RESULTS: Images obtained at 4 T showed a mean of 88 more lesions as compared with images obtained at 1.5 T. All the lesions measured less than 5 mm and were typically aligned along perivascular spaces. Twenty-five consensually identified lesions on 4-T images were not seen at all on 1.5-T images. Moreover, 4-T images showed 56 additional consensually identified lesions, which were indistinct and seen only in retrospect on 1.5-T images. These lesions were frequently (n = 48) identified in large confluent areas of white matter signal intensity abnormality at 1.5 T. All observers also agreed that 4-T images subjectively enhanced the perception of normal perivascular spaces and small perivascular lesions. CONCLUSION: MR imaging at 4 T can depict white matter abnormalities in MS patients not detectable at 1.5 T through higher resolution with comparable signal-to-noise ratio and imaging times. 相似文献
145.
JD Skinner BR Carruth KS Houck F Coletta R Cotter D Ott M McLeod 《Canadian Metallurgical Quarterly》1997,97(5):496-504
OBJECTIVE: To determine the nutrient and food intakes of healthy, white infants from families of middle and upper socioeconomic status and to compare intakes to current recommendations. DESIGN: Using an incomplete random block design, we interviewed 98 mother-infant pairs longitudinally when infants were 2, 3, 4, 6, 8, 10, 12, 16, 20, and 24 months old. Data obtained included 24-hour dietary recalls, usual food intake, and food likes and dislikes. SETTING: Interviews were conducted in the mother's home by registered dietitians. Subjects resided in two urban areas of Tennessee. SUBJECTS: Of the original 98 subjects, 94 completed the 2-year study. RESULTS: Mean energy and nutrient intakes generally met or exceeded the Recommended Dietary Allowance (RDA). Exceptions were zinc and vitamin D, which were each below 100% of the RDA at 9 of the 10 data points, and vitamin E, which was below the RDA in the infants' second year. Fat intake decreased from more than 40% of energy in the first 6 months to 30% to 32% from 10 to 24 months. One third of the infants drank reduced-fat milks at 12 months and more than half drank them at 24 months. Although infants ate a variety of foods, vegetables often were the least favorite foods. A variety of dairy products provided calcium for the infant but lacked vitamin D. CONCLUSIONS: Several nutritional issues about infant feeding before 2 years of age arose. Low intakes of zinc, vitamin D, and vitamin E were observed. In the second year, low fat intake, use of reduced-fat milks, and dislike of vegetables were areas of concern. 相似文献
146.
147.
148.
Unusual radiological opacities have been observed in 29 cases after intraarticular injection of osmic acid in 113 knees of 72 patients under treatment for a chronic exudative synovitis in different types of rheumatic diseases. They are statistically more frequent after the injection of 200 mg than after 100 mg (33.9 and 15.7% respectively). Most of the time, they are located in the suprapatellar pouch. The opacities appear soon after the injection and can last for several years. They do not seem to have an unfavorable influence on the clinical course. They appear to be caused by a deposition of osmium in synovial fat tissue. From here the osmium might stimulate fibrosis. The radiological image has to be differentiated from intra-articular calcifications, synovial ossifications and various periosteal osteogenic processes. 相似文献
149.
150.
László P. Futó 《Holz als Roh- und Werkstoff》1976,34(2):49-54
Ohne Zusammenfassung
Herrn PD Dr. H.-U. Nissen, Vorsteher des ETH-Laboratoriums für Elektronenmikroskopie H. und seinen Mitarbeitern Herrn P. W?gli
und Herrn R. Wessicken danke ich für die Unterstützung und Hilfe bei den elektronenmikroskopischen Arbeiten. 相似文献