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51.
Cytogenetic characterization of ten cases of Ph1-positive acute myelogenous leukemia 总被引:1,自引:0,他引:1
Chromosome banding analyses were made on 10 cases of Ph1-positive AML (7 M1 and 3 M2). The standard type Ph1 translocation, t(9q +;22q -), was identified in all of them. Karyotypically normal cells were observed in 6-65% of bone marrow metaphases at the initial cytogenetic examination of 7 patients, whereas the remaining 3 patients had only Ph1-positive cells at diagnosis. Follow-up studies performed in 5 cases indicated that the frequency of karyotypically normal cells increased up to 81-100% when the patients were in remission, whereas it was much reduced in relapse. In 5 cases, there was observed a clone of cells in which the Ph1 translocation was the sole karyotypic abnormality. Various types of other chromosome abnormalities, in addition to the Ph1, were observed in all cases, among which-7 was the most frequent, being found in three cases as a stem line. Other additional changes encountered were + Ph1, del(5), i(17q), - 10, + 18, + X, and various numerical and structural changes including certain secondary translocations that occurred in the Ph1 (22q -) or its partner (9q +). The types and frequencies of these additional changes appeared to be different from those found in the acute phase of CML or in Ph1-positive ALL. 相似文献
52.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats. 相似文献
53.
目的探讨抑郁认知理论的发展状况。方法从抑郁三联症和抑郁自我图式两方面对抑郁的认知理论的研究状况进行综述。结果抑郁三联症可缩减为对自我的消极想法1个维度,抑郁者消极自我图式中还存在大量积极信息。结论需要加强对抑郁认知理论的研究。 相似文献
54.
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56.
Shuji Takeshita Masanori Hosokawa Mika Irino Keiichi Higuchi Katsuji Shimizu Kimio Yasuhira Toshio Takeda 《Mechanisms of ageing and development》1982,20(1):13-23
Morphological studies on spontaneous systemic amyloidosis were conducted on 222 senescence-accelerated mice (SAM) (P) and on 150 mice in the senescence-resistant series (R).Among the pathologic findings, amyloidosis showed the highest incidence in both SAM (79.7%) and R (32.7%) Although an extensive deposition of amyloid was evident in some aged mice in the R series, a more severe amyloidosis occurred with a higher incidence in the P series. There was a statistical significance between the incidence of amyloidosis and age, in both the P and R series. There were no differences in organ distribution and mode of amyloid deposition between the P and R series or between the sexes. In about 60% of the amyloid-positive cases in the 28 killed SAM and 7 mice in the R series, there were no signs of inflammation or neoplasm.The morphological features in SAM more closely resembled those seen in cases of murine spontaneous senile amyloidosis than the features seen in cases of experimentally induced amyloidosis. This model is expected to be a valuable tool with which to assess the relationship between amyloid deposition and the aging process or senescence, perhaps even cases of human senile amyloidosis. 相似文献
57.
Gy. Kovacs 《Cancer Genetics and Cytogenetics》1981,3(2):125-129
The cytogenetic findings by G- and C-banding in a primary breast carcinoma are reported. The tumor is characterized by a high modal number of chromosomes (79) and 14 markers of ten different origins. Chromosome #1 is more frequently involved in structural and numerical aberrations than is any other chromosome; nine copies of 1q were present in each cell examined. This observation supports the hypothesis that duplication of chromosome 1q may play an important role in the progression of malignant tumors. 相似文献
58.
目的 通过对西酞普兰20mg/d治疗抑郁症的疗效、副反应和安全性的研究,探讨最佳治疗方案,提高治愈率.方法 使用汉密顿抑郁量表(HAMD)17项版本,对患者入组时的基线值,治疗时第2、4、6周分别进行评分,以评定病情严重度及其变化和疗效,记录副反应和合并用药情况.结果 发现本组病例通过西酞普兰20mg/d6周治疗后,有57.7%临床痊愈,3.8%显效,32.7%有效,5.8%改善,其有效率达94.2%.52例患者在西酞普兰治疗中可出现恶心、头痛等副反应.服药治疗6周后大多数患者副反应基本消失.结论 西酞普兰是一种安全、高效、耐受性好、副反应小、应用范围广的抗抑郁药,可作为一线抗抑郁药物使用. 相似文献
59.
The morphogenesis of testicular degeneration induced in rats by orally administered 2,5-hexanedione 总被引:5,自引:0,他引:5
The neurotoxic hexacarbon 2,5-hexanedione (2,5-HD) produces testicular atrophy in experimental animals. To examine the morphogenesis of the testicular lesion, 1.0% 2,5-HD was provided in the drinking water of adult F-344 rats for up to 6 weeks. After 3 weeks of administration, there were occasional large vacuoles in the basal region of the germinal epithelium. At 4 weeks, these vacuoles were much larger and more numerous; electron microscopy demonstrated that they were derived from the smooth endoplasmic reticulum. The vacuoles were preferentially associated with stages 12, 13, 14, and 1 of the spermatogenic cycle. Additionally, at 4 weeks there was a significant decrease in the number of tubules in stages 7 and 13, and a concomitant increase in the percentage of tubules in stages 3, 5, and 6. By Week 5, most Golgi-phase and cap-phase spermatids were visibly affected, showing margination of nuclear chromatin, and were becoming dissociated from Sertoli cells. Frequent multinucleated giant cells were seen and electron microscopy of these cells suggested that they were derived from fused spermatocytes or spermatids. After 6 weeks, fewer giant cells were present, most tubules contained cellular debris, and many showed empty lumina encircled by a thin ring of cytoplasm near the basement membrane. Interstitial tissue appeared unaffected. These studies indicate that the Sertoli cell is probably an initial target for 2,5-HD action in the testis. 相似文献
60.
A portable device for the rapid concentration of viruses from large volumes of natural freshwater 总被引:2,自引:0,他引:2
A portable device for the rapid concentration of viruses from natural freshwaters described and its performance in field use is evaluated. The system handled up to 500 litres of water in less than 90 min at a cost of only 2 pounds per sample. Where the samples contained sufficient bacteriophages for detection by direct plating the apparent phage recoveries were greater than 75%. Plant and animal viruses were also concentrated from waters with this system. 相似文献