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271.
OBJECTIVE: To compare the efficacy, tolerance and recurrence rate of endometriosis after 5-year follow-up of treatment with Gestrinone and Buserelin, respectively. STUDY DESIGN: A prospective study with randomized follow-up of 5 years duration (minimum) for each patient was done. We included 43 cases of endometriosis diagnosed by laparoscopy or laparotomy and treated them with Gestrinone (Group G, n = 25 cases) or Buserelin intranasal spray (Group B, n = 18) for 6 months. RESULTS: General data: Age, height, weight of patients and AFS score of endometriosis were without significant differences in either group. Specific data: A) Global clinical efficacy was good or excellent in 74% (16/25) of group G and in 78% (14/18) of group B without significant differences. B) Global clinical tolerance was good in 50% of the patients in group G and in 0% in group B (p < 0.001). C) Global evaluation after 5-year follow-up showed "success" only for 36% of patients in group G and in 33% in group B (no significant differences), with "failure" in 40% and 33%, respectively (no significant differences). CONCLUSIONS: 1) Gestrinone and Buserelin intranasal spray are valid treatments for the remission of endometriosis, with "success", "failure" and "clinical recurrence" rates similar after a follow-up of 5 years of initial treatment. 2) The most significant androgenic effect of Gestrinone was the presence of acne. Vascular effects were also considered as very undesirable effects according to the comments of patients. On the contrary, the effects of analogs are generally better tolerated. 相似文献
272.
We present modeling studies of quasi-three-level laser oscillators, the validity of which was revealed by Ti:Al(2)O(3)-pumped Yb:YAG laser experiments, and these results are shown to be in excellent agreement with the theory. As much as 75% slope efficiency was obtained with a hemispherical laser cavity. Previous modeling calculations of laser performance have been valid only for certain special cases, restricting application to TEM(00) Gaussian beam pumping and lasing profiles. This analysis may be applied to other longitudinally pumped quasi-three-level laser media in which the modes are not only TEM(00) Gaussian beams but also other higher-order transverse modes, including the top-hat pumping profile that can be used to model transverse pumping schemes. 相似文献
273.
The stimulation of cardiomyocyte guanylyl cyclase by nitric oxide (NO)-donor drugs was examined before and after exposure of these cells to the NO-donor drugs: S-nitroso-d,l-acetylpenicillamine (SNAP) and sodium nitroprusside (SNP). Short- (2-hr) and long-term (24-hr) exposure attenuated the maximal stimulation of GC by either SNAP or SNP by up to 80% ("desensitization"). However this "desensitization" of the myocardial GC was atypical in nature in that the reduction in maximal NO-stimulated GC activity was associated with an increase in the affinity of the GC towards either NO-donor, a finding not as yet reported. There was also evidence of "cross-desensitization" of GC (e.g., SNAP exposure decreasing the stimulatory effect of SNP). Further, this is the first time that SNAP-induced desensitization of GC has been observed. 相似文献
274.
275.
Role of polychlorinated dibenzofuran in yusho (PCB poisoning) 总被引:1,自引:0,他引:1
T Kashimoto H Miyata S Kunita TC Tung ST Hsu KJ Chang SY Tang G Ohi J Nakagawa S Yamamoto 《Canadian Metallurgical Quarterly》1981,36(6):321-326
In the blood of 15 patients with yusho or "polychlorinated biphenyl poisoning" that occurred in 1979 in Taiwan, was found polychlorinated dibenzofurans (14 of 15) and polychlorinated quaterphenyls (15 of 15), as well as polychlorinated biphenyls (15 of 15). The mean concentration ratio of these substances was approximately 1 : 160 : 500. Based on the following evidence, we propose that polychlorinated quaterphenyls were major pathogenic substances in the development of yusho: (1) Clinical manifestations and course of yusho patients are disproportionately severe and persistent for the observed blood levels of polychlorinated biphenyls, while patients who were occupationally exposed to pure polychlorinated biphenyls take characteristically mild and benign clinical course despite polychlorinated biphenyl levels often much higher than those noted in yusho patients; (2) Polychlorinated debenzofurans show a marked tendency to accumulate in the liver, which might explain frequent presence of jaundice and other abdominal symptoms in yusho, which are, again, not observed in those with occupational polychlorinated biphenyl poisoning; (3) Toxicity of polychlorinated dibenzofurans is a hundred to ten thousand times greater than that of polychlorinated biphenyls and polychlorinated quaterphenyls in animal experiments. 相似文献
276.
Giuseppe Pezzotti Isao Tanaka Taira Okamoto 《Journal of the American Ceramic Society》1990,73(10):3033-3038
A microstructural evaluation of Si3 N4 with 20 vol% SiC whiskers, fully densified by hot isostatic pressing (HIP) without sintering aids, is presented. The grain size and morphology of the matrix, the whisker aspect ratio after sintering, interfacial bonding, and the structural stability of reinforcement up to 2000°C are discussed. Image analysis provides quantitative information about whisker dispersion and orientation. It is pointed out that a whisker dispersion and orientation. It is pointed out that a whisker composite with a high degree of homogeneity and isotropy can be obtained by optimizing the mixing procedure and using HIP. 相似文献
277.
Giuseppe Pezzotti Isao Tanaka Taira Okamoto 《Journal of the American Ceramic Society》1991,74(2):326-332
The fracture behavior at high temperature of a Si3 N4 -based SiC-whisker composite fabricated by hot isostatic pressing without sintering aids is compared with that of other highly refractory materials. Particular attention is directed toward evaluating the slow-crack-growth resistance of the composite up to 1440°C and relating this resistance to the microfracture behavior of Si3 N4 grains, SiC whiskers, and the intergranular, glassy SiO2 phase. Only thick whiskers operate to bridge the wake of the crack; these whiskers may make a positive contribution to the slow-crack-growth resistance. Impurities detected by EDX microanalysis at the grain boundary, however, apparently degrade the high-temperature properties, a finding supported by internal-friction measurements. Nevertheless, the high potential of the system without sintering aids for high-temperature structural applications has been demonstrated by the time to failure estimated from the measured slow-crack-growth resistance for a fixed flaw size. 相似文献
278.
279.
Keiichi Koda Shogo Taira Atsushi Kubota Tomofumi Isozaki Xiangyu You Yasumitsu Uraki 《木材化学与工艺学杂志》2019,39(3):198-213
For new application of technical lignins as separator material for electric double-layer capacitor (EDLC), we tried first to prepare bipolyester film by melt-polycondensation of polyethylene glycol lignin (PEGL) and maleic anhydride. The EDLC assembled with this film, however, showed lower electrochemical performance than the reference EDLC with commercial cellulosic separator. Porous bipolyester film was then prepared and the resulting EDLC exhibited improved specific capacitance, but high intrinsic and charge transfer resistances. Non-porous terpolyester film was prepared next, using polyethylene glycol 500,000 to improve flexibility of the film, which might lower the resistances. This film was flexible enough and provided the resulting EDLC with superior electrochemical performance to the bipolyester film. EDLC with porous terpolyester film was finally prepared and showed the highest electrochemical performance, comparable to the reference EDLC. Porous morphology and flexibility were key factors to fabricate lignin-based self-standing film as separator material for high-performance EDLC. 相似文献
280.
The extract of Agrimonia pilosa Ledeb, with a high polyphenol content, inhibited nitrite accumulation as an indicator of nitric oxide (NO) in LPS-induced RAW264.7 macrophages. The NO inhibitory compounds in the extract were isolated using open column chromatography and HPLC, and five phenolic compounds, namely aromadendrin (AD), dihydrokaempferol 3-O-β-D-glucoside (DK3-O-glc), quercitrin (QC), aglimonolide-6-O-β-D-glucoside (AG6-O-glc) and loliolide (LL), were determined by 1H, 13C NMR and LC/MS analyses. This is the first time that these compounds have been isolated from this plant. 4-Ethyl-2-hydroxyamino-5-nitro-3-hexenamide (NOR3), as a NO donor, was used in the presence of these compounds and then the nitrite-level, as an index of NO, decreased, indicating that these compounds would potentially have a NO-scavenging activity. An ESR study of the system containing NOR3 and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), as a NO detection reagent, with or without the compound, provided the evidence that these compounds directly scavenged NO and the scavenging activities of three flavonoids (AD, DK3-O-glc and QC) were remarkably high in comparison to those of the other phenolic compounds. These results indicated that one of the suppression mechanisms in cells would be the NO-scavenge of phenolic compounds. 相似文献