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141.
142.
The t(1;19)(q23;p13) has been reported in up to 6% of cytogenetically abnormal cases of acute lymphoblastic leukaemia (ALL), associated with a pre-B-ALL phenotype. In the 5-year period 1995-1999, we detected t(1;19) in 13 children and 2 adults with newly diagnosed ALL. This represented 10% of pediatric and 2.5% of adult diagnostic ALL samples successfully cultured in one center during this time. There were 9 males and 6 females. The mean age at diagnosis for the 13 children was 6.5 years (range 1.5 to 14 years) and the 2 adults were aged 42 and 45 years. The unbalanced t(1;19) occurred in 7 of 13 children (54%), contrary to the reported excess of unbalanced translocations at 75%; both adults had the unbalanced translocation. At diagnosis, the t(1;19) was the sole abnormality in 4 patients (26%), and in the remainder (74%) was part of a complex karyotype, which included i(7q) (2 patients), hyperdiploidy (2 patients) and del(6q) (2 patients). Correlation of karyotype with white cell, blast and platelet counts, cell surface markers, initial response to chemotherapy and short-term outcome showed no difference between the balanced and unbalanced forms of the translocation in children or whether t(1;19) was present as the sole abnormality or part of a complex karyotype. 相似文献
143.
Summary Biochemical studies on the two transaminases GOT and GPT of swine kidney worm Stephanurus dentatus have been made. GOT has been found much more active than GPT. Enzyme activities are based on the formation of oxaloacetate (GOT) or pyruvate (GPT) from aspartic acid and alanine respectively with oxoglutarate. A linear relationship is observed between the enzyme concentration and activity. GOT shows a maximum activity at pH 8.0 and Michaelis constant 9×10–3 M for male and 2.9×10–3 M for female. GPT has an optimum pH of 7.5 and a Michaelis constant 19×10–3 M for male and 8×10–3 M for female. The optimum temperature for both GOT and GPT was 60° C. 相似文献
144.
Cell-mediated immune responses of lambs to challenge with bovine respiratory syncytial virus. 下载免费PDF全文
The lamb is a good model to study the pathogenesis and immune responses to infections with respiratory syncytial virus (RSV) as lambs experimentally infected with bovine or human RSV may develop overt clinical disease. In the present study the development of cellular cytotoxic responses was studied in splenic, pulmonary and peripheral blood mononuclear cells obtained from lambs after primary and secondary infection with bovine RSV. Infection with bovine RSV was followed by the appearance of cytotoxic cells in the peripheral blood, the spleen and lung lavage fluids. These effector cells lysed virus-infected targets in a self-restricted manner. Depletion techniques revealed that cytotoxic activity was largely due to OvCD8+ cells. When effector cells obtained from primed lambs were stimulated with inactivated bovine RSV or with virus-infected cells in vitro, virus-specific cytotoxicity was significantly increased. 相似文献
145.
Induction of genotoxic damage is not correlated with the ability to methylate arsenite in vitro in the leukocytes of four mammalian species 总被引:1,自引:0,他引:1
Arsenic is a natural drinking water contaminant that impacts the health of large populations of people throughout the world; however, the mode or mechanism by which arsenic induces cancer is unclear. In a series of in vitro studies, we exposed leukocytes from humans, mice, rats, and guinea pigs to a range of sodium arsenite concentrations to determine whether the lymphocytes from these species showed differential sensitivity to the induction of micronuclei (MN) assessed in cytochalasin B-induced binucleate cells. We also determined the capacity of the leukocytes to methylate arsenic by measuring the production of MMA [monomethylarsinic acid (MMA(V)) and monomethylarsonous acid (MMA(III))] and DMA [dimethylarsinic acid (DMA(V)) and dimethylarsonous acid (DMA(III))]. The results indicate that cells treated for 2 hr at the G(0) stage of the cell cycle with sodium arsenite showed only very small to negligible increases in MN after mitogenic stimulation. Treatment of actively cycling cells produced induction of MN with increasing arsenite concentration, with the human, rat, and mouse lymphocytes being much more sensitive to MN induction than those of the guinea pig. These data gave an excellent fit to a linear model. The leukocytes of all four species, including the guinea pig (a species previously thought not to methylate arsenic), were able to methylate arsenic, but there was no clear correlation between the ability to methylate arsenic and the induction of MN. 相似文献
146.
Avasthi A Sharma A Gupta N Kulhara P Varma VK Malhotra S Mattoo SK 《Journal of affective disorders》2001,64(2-3):145-154
Case records of the patients with major affective disorders (ICD-10 criteria), seen over a 5 year period in a busy clinic in North India were examined for Seasonal Affective Disorder (SAD) as per DSM-III-R criteria. In addition, seasonality of episodes of all affective disorders was also studied. Around 5.67% of the cases (n=44) retrospectively met the DSM-III-R criteria of SAD and predominant pattern was that of summer depression (n=18). There was also a consistent pattern of seasonal mania either in conjunction with seasonal depression (n=18) or in form of seasonal recurrent mania (n=11). None of the cases of depression showed any atypical vegetative features. In cases not meeting criteria for SAD (n=731), there was a trend for peaks for depressive episodes in winter followed by a smaller peak in summer months while manic episodes had peaks towards rainy and winter months. As compared to seasonal patterns of affective disorders in temperate zones, there was a general trend for opposite patterns of seasonality in SAD as well as in non-SAD. The findings are discussed in context of the climatic conditions of North India. 相似文献
147.
The immunotoxic potential of ENU, a potent and transplacental neurocarcinogen, was evaluated in male CD1 mice. The animals received i.p. injections of ENU--0, 2, 8 or 32 mg/kg body weight, in citrate-phosphate buffer, twice weekly for three weeks. Splenic lymphocytes were cultured in the presence of mitogens, lipopolysaccharide, pokeweed mitogen, concanavalin A and phytohaemagglutinin. Mixed lymphocyte cultures in the presence of allogeneic cells were also tested. Blastogenic response decreased in a dose-dependent manner, as measured by the 3H-thymidine uptake by splenocytes. Primary antibody production by splenic lymphocytes from animals challenged with a T-dependent antigen (sheep red blood cells) was stimulated at low doses but depressed at the highest dose group compared with the controls, whereas T-independent cell response showed no significant change. Our results suggest that exposure to repeated, low levels of ENU significantly alters the immune status of CD1 mice. The effects appear to be somewhat selective to T cell processes, based on in vivo responses to T-dependent and T-independent antigens. 相似文献
148.
An unusual variation creates interest among anatomists, but is a cause of concern among clinicians when it mimics a pathology. The sternalis muscle is one such variant of the anterior chest wall located subcutaneously over the pectoralis major, ranging from a few short fibers to a well-formed muscle. We observed a bilateral case, which was accompanied by an atypical presentation on the left side where a huge, bulky sternalis muscle was associated with the absence of the sternal fibers of the pectoralis major. The fibers arose as a lateral strip from the upper two-thirds of the body of the sternum and costal cartilages 2 through 6 with the intervening fascia and aponeurosis of the external oblique. The right sternalis was strap-like and was placed vertically over the sternal fibers of the pectoralis major, arising from the underlying fascia and aponeurosis of the external oblique. The sternalis muscles, on each side, converged into an aponeurosis over the manubrium that was continuous with the sternal heads of the right and left sternocleidomastoid muscle, respectively. This rare anomaly has puzzled radiologists and surgeons in confirming diagnosis, missing it all together or mistaking it for a tumor on mammography or CT scan. These findings prompted us to review its topography, development, and application in relation to the anterior chest wall. 相似文献
149.
150.
H. H. Sharma S. K. Kacker 《Indian journal of otolaryngology and head and neck surgery》1985,37(1):31-33
Microlaryngoscopic studies were conducted in 7 cases of hypothyroidism and 18 cases of benign goitres. Histopathological observations were made in all hypothyroid cases and 17 goitres. Pale and thickened vocal cords with sub-epithelial oedema were found in all cases and mild to moderate accumulation of mucopolysaccharides in the subepithelial stroma of vocal cords in 71% of the cases of Hypothyroidism. In cases of goitres, oedematous vocal cords were detected in 28%, pale irregularly thickened vocal cords in 33% and vocal nodules in 11% of the cases. Acid mucopolysaccharide accumulation in the vocal cords was noted in 2 cases of diffuse goitres. Left vocal cord palsy in one case of solitary nodular goitre was also noted. 相似文献