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Cytochemical analysis of leukemic blasts from 46 patients with acute myeloblastic M2 leukemia (according to the FAB classification) was performed before and after cytostatic therapy, and compared with findings obtained in 20 age- and sex-matched control subjects. Cytochemical findings for myeloperoxidase (MPO), Sudan black B, acid phosphatase and alpha-naphthyl-acetate esterase (ANAE) were related to the achievement of the first complete remission (CR),i.e. data were compared after the patients had been divided into CR and non-CR groups. The analysis clearly showed that a high proportion of myeloperoxidase- and, to a lesser extent, Sudan black B-positive blasts before treatment may have constituted a significantly unfavourable prognostic factor.  相似文献   
3.
BACKGROUND: Recent hospital and cancer registry data show increasing prostate cancer incidence in Nigeria, which was previously regarded as a low incidence region. This study investigates the prevalence of prostate cancer risk in a previously unscreened cohort of rural Nigerians. METHODS: Rural Nigerian men, 40 years and older, were screened by serum prostate-specific antigen (PSA) and digital rectal examination (DRE) and those with PSA >/= 4 ng/mL and/or abnormal DRE were referred for prostate biopsy. RESULTS: Of 200 consecutive men invited, 151 (75.5%) presented for screening, the mean age was 56.45 + 15.1 and 95 (61.6%) were >/= 50 years of age. Of the 140 who consented to a blood test, PSA correlated with age (r = 0.3, P < 0.01), 14 (10.0%) had abnormal PSA >/= 4 ng/mL, increasing from 3 (3.6%) in men < 60 years to 4 (50%) in men >/= 80 years. The rate was 13 (15.7%) for men >/= 50 years and there was no evidence of increased incidence of prostatitis in the community. Mean (median) PSA in ng/mL increased from 1.17 (0.60) in the youngest to 13.75 (4.45) in the oldest cohort. Of those who accepted DRE, 38 (29.0%) had an enlarged prostate, including two who had nodular prostate, one-third with symptoms, increasing from 4 (5.4%) in those < 50 years to 6 (75.0%) in men >/= 80 years. The proportion of men with PSA >/= 4 ng/mL among those with enlarged vs normal prostate is 27.0 to 3.4%, P < 0.001, and the pattern was similar for men >/= 60 years and those < 60 years of age. The 40 (32.0%) men referred for prostate biopsy defaulted mainly because they did not fully understand the need for further investigation because they were symptom free or afraid of the possible side-effects of the procedure or diagnosis of cancer. CONCLUSION: The proportion of men with PSA >/= 4 ng/mL is comparable to that of previously unscreened populations with high incidence of prostate cancer such as African-American men. A larger study is required to confirm these findings and intensify efforts to determine the prostate cancer detection rate by biopsy in this population. A prostate cancer awareness and education campaign will be useful in this community.  相似文献   
4.
研究了LDPE/CPE/炭黑三相复合导电体系的导性能和电流-电压特性。实验结果表明复合体系具有明显的导电渗滤效应,在共混比LDPE/CPE>50/50时,导电性能随CPE含量增加而显著提高,这主要是由于炭黑粒子在LDPE和CPE两组分分中的分布不均匀性所致。  相似文献   
5.
Hospital discharge data from New Jersey were used to identify cases of asbestosis for the 8 years 1979-1986. Multiple admissions were deleted so that each individual was counted once at the time of his/her first hospitalization with an asbestosis diagnosis. White males had the highest age-adjusted average annual discharge rate of 19.3 cases/100,000 population, followed by black males (12.3 cases/100,000) and white females (1.2 cases/100,000). The discharge rate was positively associated with age in each race/sex category. The relationship between rates for black males and white males depended on age: under 65 years, the rates were almost equal, and at 65 years and older, the white rates were nearly twice the black rates. There were two areas of the state where the rates were highest: the north-central and southwest regions. These two areas represent manufacturing and shipbuilding applications of asbestos, respectively. During the years 1979-1986, the annual percentage increase in asbestosis rates was 20% for white males, 17% for black males, and 8% for white females. Continued surveillance will reveal when the rates for asbestosis stop increasing.  相似文献   
6.
从桑椹成熟果实、桑叶以及桑果园的土壤采样,进行桑椹果酒专用酵母的筛选,得到一株在性能上优于对照菌葡萄酒干酵母的酵母菌Y11。该菌起酵快,从第2天开始糖度大幅度下降,酒精度快速上升,发酵第4天酒精体积分数即可达到10%以上。发酵过程pH值变化趋势比较平缓,发酵结束后高级醇量符合要求。综合发酵性能及感官评定,表明该菌能代替葡萄酒干酵母用于桑椹果酒的生产。  相似文献   
7.
本试验采用食饵迷宫法和一次训练被动回避性条件反应——跳台法,观察了楮实对小鼠学习和记忆的促进作用。结果表明,楮实对正常小鼠的空间辨别学习、记忆获得有促进作用;可拮抗东莨菪碱造成的记忆获得障碍;改善氯霉素和亚硝酸钠造成的记忆巩固不良;改善30%乙醇引起的记忆再缺损,并对亚硝酸钠中毒缺氧有明显的改善作用。  相似文献   
8.
Fluid Flow through Filtering Appendages of Insects   总被引:4,自引:0,他引:4  
Many organisms use structures composed of arrays of cylindersto capture particulate food or molecules form the water or airaround them. The performance of such filters depends on thevelocity of fluid movement through them; hence, mathematicalmodels of flow through fibrous structures can provide insightsabout the functional morphology of biological filters. In thispaper, the authors address the case of feather-like biologicalfilters of finite width and assess several possible models forfluid motion through them by comparing model predictions withobservational data. Two examples of insect appendages are considered:the cephalic fans of black fly aquatic larvae that capture particulatefood and the antennae of adult male moths that catch sex-attractantmolecules released by female moths. The results suggest thatflow through such structures can be much slower than ambientcurrents, that the finest hairs in the structure are the morphologicalfeatures with the greatest effect on leakiness, and that thevelocity of movement (or of ambient flow), as well as the morphologyof such filters, can be critical in determining their performance.  相似文献   
9.
目的:对云南地区习用的藁本品种进行考证。方法:文献调研,实地考察。对文献中记地匠“藁本”进行比较分析,在云南几个主产区、集散地进行实地考察,结合生药鉴定做出评价。结果:通过研究,发现云南地区用的藁本是黄蒿本和黑藁本两个品种,黄藁本的基源是伞形科滇芹属植物滇芹Sinodielsia yunnanensis Wolff和藁本属植物丽江藁本Ligusticum delavayi Franch.,黑藁本的其源是伞形科藁本属植物蕨叶藁本L.pteridophyllum Franch,。结论为现代研究及临床用药提供依据。  相似文献   
10.
Laparoscopic resection for a left adrenal black adenoma   总被引:2,自引:0,他引:2  
Adrenalblackadenoma (pigmentedadenoma)isquiterare Recently,weperformedalaparoscopicresectionforafunctioningadrenalblackadenoma Wereportthecasehere CASEREPORTA 2 1 year oldfemalewasadmittedtoourhospitalbecauseofamenorrheaandobesity ShepresentedwithtypicalCus…  相似文献   
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