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101.
M Morita I Tsuge H Matsuoka Y Ito T Itosu M Yamamoto T Morishima 《Canadian Metallurgical Quarterly》1998,50(5):1485-1488
The objective of this study was to determine whether measurements of human CRH in the inferior petrosal sinuses could distinguish patients with Cushing's syndrome from those with pseudo-Cushing states or normal physiology. Twenty-five patients with Cushing's disease, 17 patients with the syndrome of ectopic ACTH, 7 patients with Cushing's syndrome of adrenal origin, 6 patients with pseudo-Cushing states, and 11 volunteers believed to have normal hypothalamic-pituitary-adrenal axes were studied. Basal plasma human CRH and ACTH were measured at two time points in the petrosal sinuses and in a peripheral vein. Most subjects were studied after the administration of intravenous diazepam or midazolam and fentanyl, but because of the known inhibitory effects of such sedation on CRH secretion, 2 normal volunteers and 3 patients with pseudo-Cushing states were studied without sedation. Human CRH levels were near or below the detection limit of the assay in all subjects. Although the normal volunteers and patients with pseudo-Cushing states who were studied without sedation had significantly greater inferior petrosal sinus ACTH levels than those who received sedation, there were no differences in measured human CRH levels for any of the groups. We conclude that inferior petrosal sinus human CRH levels are not easily measured in the inferior petrosal sinuses and cannot be used to determine whether individual patients may have hypersecretion of CRH causing their ACTH secretion. 相似文献
102.
103.
K Sugi K Nawata N Fujita K Ueda T Tanaka T Matsuoka Y Kaneda K Esato 《Canadian Metallurgical Quarterly》1998,22(3):290-4; discussion 294-5
The value of radical systematic lymphadenectomy for treatment of early-stage bronchial carcinoma is controversial. We performed a prospective randomized study to address this question. Altogether 115 patients with peripheral non-small-cell lung cancers smaller than 2 cm in diameter were enrolled in this study. They were randomly assigned into a lobectomy with lymph node sampling group (sampling group, n = 56) or a lobectomy with radical systematic lymph node dissection group (dissection group, n = 59). Inclusion criteria were based only on preoperative clinical studies. Four tumors were larger than 2 cm postoperatively. One patient had disseminated disease, and two had intrapulmonary metastases discovered at surgery. Two patients had small-cell carcinoma. There were four with pathologic N1 disease and seven with N2 disease in the dissection group and three with N1 and eight with N2 disease in the sampling group. The numbers of local and distant recurrences were two and six, respectively, in the dissection group and two and five in the sampling group. The overall 5-year survival was 81% in the dissection group and 84% in the sampling group. No significant differences in the recurrence rate or survival was seen between the groups. Our results demonstrate that clinically evaluated peripheral non-small-cell carcinomas smaller than 2 cm in diameter do not require radical systematic mediastinal and hilar lymph node dissection. 相似文献
104.
105.
K Sugi N Fujita K Ued K Nawata T Tanaka T Matsuoka Y Kaneda K Esato 《Canadian Metallurgical Quarterly》1997,45(10):1701-1705
The indications for a video-assisted lobectomy are currently ill-defined. Clinicians recommend based on the extent of lymph node involvement. Fifty-nine patients with clinical stage I non-small cell lung cancer underwent lobectomies with systemic lymph node dissections through a standard thoracotomy (Group C), and 26 patients underwent lobectomies with lymph node dissections using the video-assisted procedure (Group V). The number of dissected lymph nodes at all node levels were compared between the two groups. There was no significant difference between groups in the total number of dissected lymph nodes in patients with right lung cancer. The number of dissected hilar and interlobar lymph nodes, however, was less in Group V than that in Group C (hilar: 1.2 +/- 0.4 vs. 2.8 +/- 0.6, interlobar: 1.1 +/- 0.4 vs. 2.1 +/- 0.4). The total number of dissected lymph nodes in patients with left lung cancer was significantly less in Group V than that in Group C (18.5 +/- 0.3 vs. 28.7 +/- 2.4). In addition, the number of dissected lymph nodes in pratracheal, pretracheal, tracheobronchial, subcarinal, hilar, and interlobar lymph nodes were significantly less in the group V than those in Group C. Although there was no significant difference in the actual survival rates between the groups in this preliminary study, a sufficiently small number of dissected lymph nodes in the video-assisted lobectomy may have resulted in inaccurate staging and poor prognosis in these patients. 相似文献
106.
Kazuyuki Tohji Kan Saito Balachandran Jeyadevan Isao Matsuoka Toshiaki Sogabe Ken Nagasawa 《Fullerenes, Nanotubes and Carbon Nanostructures》1997,5(1):33-47
Production of fullereries using electrodes made of four kinds of pure carbon bearing materials and artificial graphite doped with seven kinds of elements such as B, Y, La, Gd, Ce, Pr and Nd have been examined. The yields of fullerenes were in a range between 12-20% of the soot produced for all pure carbon electrodes, even though the vaporization rate of amorphous carbon electrodes was about ten times higher than that of the natural graphite electrodes. However, for the doped graphite electrodes, the yield of fullerenes was less than 5%. From the above results it is concluded that fullerenes can be effectively produced with the pure carbon electrodes made of any form of carbon bearing materials used in this study and there is little material dependence on the yield of fullerences. Furthermore, the experiments using the artificaial graphite electrodes doped with metal elements suggests that the purity of the carbon electrodes affects the yeld of fullerenes greatly. 相似文献
107.
108.
T Gabata O Matsui M Kadoya K Ueda Y Kawamori J Yoshikawa K Nobata Y Fujinaga T Matsuoka T Takashima 《Canadian Metallurgical Quarterly》1997,22(5):502-505
BACKGROUND: Aberrant gastric venous drainage (AGVD) into the posterior edge of the medial segment of the liver (segment IV) is the main cause of pseudolesion on computed tomography (CT) during arterial portography. We estimated the prevalence of AGVD into the medial segment of the liver with color and power Doppler ultrasound (US). METHODS: Screening gray-scale and color Doppler and power Doppler US were performed in 100 consecutive patients. AGVD was defined as a venous structure that ascended parallel to the main portal vein and drained independently into segment IV. RESULTS: AGVDs were observed in eight of 100 patients (8%) with color and power Doppler US. Power Doppler US depicted these veins more clearly than did color Doppler US. Gray-scale US did not show any AGVDs. Two of eight patients with AGVDs detected by color Doppler US underwent celiac arteriography and CT during arterial portography (CTAP). In these two patients, celiac arteriography directly demonstrated AGVDs draining into segment IV, which revealed nontumorous perfusion defects (pseudolesions) on CTAP. CONCLUSION: Color and power Doppler US are useful imaging methods for demonstrating AGVDs. 相似文献
109.
A male rat put in an open-field arena in which it is free to spend time in the vicinity of--but not in contact with--an estrous female, or in the vicinity of a male, usually spends more time with the female than with the male or elsewhere. Tentatively, the percentage of time spent in the vicinity of the female in this paradigm may be regarded as a measure of sexual motivation. In humans, treatment with selective serotonin reuptake inhibitors (SSRIs) may cause reduced libido. To investigate to what extent serotonin reuptake inhibition influences sexual motivation also in rats, we have tested the effect of subchronic treatment with fluoxetine on the behavior in the sexual motivation test described above; in addition, the effect of fluoxetine on male copulatory behavior was studied. Fluoxetine significantly reduced sexual motivation at subchronic but not at acute administration; moreover, fluoxetine-treated rats displayed an increased ejaculation latency. It is concluded that humans and rats respond similarly to the SSRI fluoxetine with respect to various aspects of sexual behavior. 相似文献
110.
Recently, the simulated annealing has been applied to several combinatorial optimization problems. In this paper, the simulated annealing method for continuous functions is reviewed, and it is applied to an economic model having multiple optimal solutions, in which all optimal solutions cannot be simultaneously obtained by Scarf's algorithm. 相似文献