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131.
The ETV6 (TEL) locus at chromosome band 12p 13 is a major site of translocations in acute leukemia, particularly in childhood acute lymphoblastic leukemia (ALL). In cases with translocations involving ETV6, the normal ETV6 allele is often deleted. In addition, loss of heterozygosity of ETV6 is frequently observed in childhood'ALL. Thus, it has been suggested that ETV6 may have an anti-oncogenic role to play, in addition to its oncogenic role. We have described an unusual case of ALL in which ETV6 is found fused to the ABL gene; ABL is normally activated by fusion to the BCR gene in the 9:22 translocation. We expanded the primary cells from this ETV6/ABL rearranged case of ALL in SCID animals and analyzed them for expression of both ETV6/ABL and the normal ETV6 mRNA. We found that both the rearranged and normal ETV6 mRNAs are expressed in the expanded cell population. Furthermore, sequence analysis of the ETV6 PCR product revealed no point mutations which would influence the amino acid sequence. Thus, deletion of the second ETV6 allele is not necessary for the transformation to leukemia by ETV6/ABL.  相似文献   
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An evaluation was done of the state of bulbar microcirculation and aggregability of blood platelets in 47 patients presenting with early manifestations of cerebral circulatory insufficiency. A correlation was established between the revealed disturbances in the microcirculatory bed and augmentation of aggregational activity of thrombocytes. Computation of the integrative guide, microcirculatory-rheologic index, reflecting objectively the degree of intravascular hemocirculatory disorders has been performed. Treatment with calcium antagonist corinfar, antihypoxic agent actovegin was of particular benefit for the patients when administered in combination; more than half of the parameters characterizing microcirculation, rheologic properties of blood, microcirculatory-rheologic index have all returned to normal.  相似文献   
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We studied the mutagenic potential of the trematode Opisthorchis felineus in experimentally infected guinea pigs by chromosome analysis. The investigation was conducted on 30 treated (experimentally infected) and 20 normal (uninfected) guinea pigs (Cavia porcellus). A sample of living metacercariae of O. felineus was obtained from the muscle of naturally infected crucian carp captured in the Tom River, and 1 ml suspension containing approximately 50 metacercariae in 0.9% NaCl solution was individually given p.o. to guinea pigs that were used as treated specimens, whereas normal guinea pigs from the same stock were given 1 ml 0.9% NaCl solution per individual to serve as controls. The treated and control animals were killed by CO2 asphyxiation and decapitation at 7, 15, 30, 45, and 120 days after contamination. The smears of bone marrow cells for chromosome analysis were prepared by a standard method. Statistical analysis of the data was done using Student's t-test. We found that experimental infection of guinea pigs with O. felineus induced significantly high frequencies of hypoploid cells and, at the 120th day p.i., led to a considerable incidence of chromatid breaks and polyploidy in bone marrow cells.  相似文献   
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Evidence-based medicine is the conscientious, explicit, and judicious use of the best evidence available to make decisions about the care of individual patients. The practice of EBM means integrating individual clinical expertise with the best available external clinical evidence from systematic research. The good practice of EBM begins with a well formulated clinical question, meaning that it should be clear, directly relevant to the problem at hand and answerable by searching in medical literature. This paper begins by presenting the central tasks of clinical work from which clinical questions arise. The components of well formulated clinical questions are then presented. Finally, some of the steps for the correct formulation of questions are discussed.  相似文献   
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BACKGROUND: Because cigarette smoking affects the respiratory system earlier than many other systems of the human body, an attempt was made to identify objective and subjective respiratory problems among adolescent smokers. METHODS: Two studies based on a pulmonary function test (PFT), respiratory symptom assessment, and other smoking-related variables were undertaken. Study 1 involved cigarette smokers (N = 18, 22% males, mean age 18.7 years) from a freshman college class who participated in an acute smoking experiment that involved performing a PFT before and after smoking a single cigarette. Study 2 was performed on a combined group of vocational-technical high school students and freshman college students (N = 44, 48% males, mean age 17.8 years) where PFT parameters, respiratory symptoms, and smoking-related health vulnerability were assessed among smokers vs nonsmokers. RESULTS: In Study 1, the average reduction across PFT parameters was 4.4% and the mean estimated lung age increased from 27.15 to 29.84 years. In Study 2, a consistent trend toward reduction of PFT values among smokers vs nonsmokers was observed; the mean forced expiratory volume in 1 sec/forced vital capacity ratio (90.51% vs 94.59%), peak expiratory flow rate (80.32% vs 92.06%), and flow rate of 50% of forced vital capacity (88.39% vs 102.81%) differed significantly. Significant differences in respiratory symptoms were also observed among smokers vs nonsmokers. CONCLUSIONS: The beginning of respiratory health disorders can be identified among adolescent smokers. These findings might provide important clues on how to improve outcomes from health care provider-based adolescent smoking cessation counseling.  相似文献   
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The effects of an alternative chelation program in thalassemic patients with severe iron overload are investigated. The schedule of treatment, feasible at home, consists in the administration of deferoxamine intravenously (100 mg/kg/die 8 hours 10 days a month), followed by 50 mg/kg/die subcutaneously in the remaining 20 days of the month. The results in 34 patients who underwent this program over 8 months are reported. After intensive chelation therapy serum ferritin and transaminase levels were significantly lower, and daily urinary iron excretion values were significantly higher when compared to the levels observed before the treatment. After the period of study, echocardiography revealed an ejection fraction (EF) significantly higher in 15 out of 34 cardiopathic patients. In conclusion, the alternative chelation program is effective in reducing iron overload of thalassemic patients, protecting them also against cardiac disease.  相似文献   
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We have investigated the subcellular localization of the SMC protein in the gram-positive bacterium Bacillus subtilis. Recent work has shown that SMC is required for chromosome condensation and faithful chromosome segregation during the B. subtilis cell cycle. Using antibodies against SMC and fluorescence microscopy, we have shown that SMC is associated with the chromosome but is also present in discrete foci near the poles of the cell. DNase treatment of permeabilized cells disrupted the association of SMC with the chromosome but not with the polar foci. The use of a truncated smc gene demonstrated that the C-terminal domain of the protein is required for chromosomal binding but not for the formation of polar foci. Regular arrays of SMC-containing foci were still present between nucleoids along the length of aseptate filaments generated by depleting cells of the cell division protein FtsZ, indicating that the formation of polar foci does not require the formation of septal structures. In slowly growing cells, which have only one or two chromosomes, SMC foci were principally observed early in the cell cycle, prior to or coincident with chromosome segregation. Cell cycle-dependent release of stored SMC from polar foci may mediate segregation by condensation of chromosomes.  相似文献   
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