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291.
Screening detection of the antigens of some pathogenic enterobacteria in the coagglutination test with the use of Shigella (S. sonnei, S. flexneri 2a, 1b, 6), Salmonella (groups A, B, C, D, E) and Yersinia (Y. pseudotuberculosis, serovars I and III, Y. enterocolitica 03 and 09) diagnostica in patients with chronic enteric diseases, hospitalized in a noninfectious ward, has demonstrated a high incidence of the above antigens. S. flexneri antigens have shown the highest detection rate. The results thus obtained indicate that these infective agents probably take part in the development of exacerbations of chronic enteric diseases and, therefore, a comprehensive examination of this group of patients is necessary with a view to the detection of bacterial enteric infection.  相似文献   
292.
From January 1991 to May 1992 transluminal balloon valvuloplasty [correction of vulvoplasty] of severe valvular stenosis of the pulmonary artery was performed in 14 patients with Fallot's tetrad at the Institute of Cardiovascular Surgery named after A. N. Bakulev. Five of them had pulmonary artery hypoplasia, 2 had stenosis and hypofunction of the systemic-pulmonary anastomosis applied by the Blalock-Taussig, which made them perform balloon angioplasty of the narrowed distal portion of the anastomosis. The patients' age ranged from 11 months to 14 years (mean age 6.8 +/- 1.1 years). Arterial blood oxygen saturation varied from 51 to 72% (mean 69.2 +/- 2.4%). The diameter of a valvular ring was 8-13 mm. The diameter of a balloon catheter exceeded that of the valvular ring by 20-25%. After dilation, arterial blood oxygen saturation increased from 69.86 +/- 2.5 to 85.1 +/- 1.2%. The angiometry performed after pulmonary artery valvuloplasty in patients with pulmonary hypoplasia showed an increase in sizes of all pulmonary arterial segments on an average by 22.5 +/- 4.1%. Later on 5 patients were radically operated on. Thus, with the ultimate goal of preparation of patients with severe Fallot's tetrad for radical surgery, transluminal balloon valvuloplasty in some patients with severe valvular stenosis of the pulmonary artery may be alternative to a systemic-pulmonary anastomosing operation.  相似文献   
293.
32P-Postlabelling of DNA extracted from the livers obtained from seven women receiving tamoxifen (20 mg either once or twice daily) was compared with liver DNA from seven individuals not receiving this drug. In all but one of the treated women, tamoxifen and its N-desmethyltamoxifen metabolite could be detected in liver extracts by high performance liquid chromatography; none was detected in control samples. The total level of 32P-postlabelled DNA adducts extracted from the tamoxifen treated women ranged between 18-80 adducts/10(8) nucleotides. The pattern of 32P-postlabelled adducts was not the same as those seen in rats dosed with this drug. There was no significant difference in the level of DNA damage between the tamoxifen treated and control groups. Although only a small number of subjects has so far been examined it appears that women are less susceptible to liver DNA damage caused by tamoxifen than rats.  相似文献   
294.
Identification of inexpensive and technically simple immunological tests useful in predicting the progression to AIDS in human immunodeficiency virus (HIV)-infected patients would be especially welcome in developing countries, in which 80% of HIV-infected patients reside and health budgets are low. In the current study, we evaluated CD4+ and total lymphocyte counts and the concentrations in serum of beta 2-microglobulin, p24 antigen, and immunoglobulin A (IgA) as predictors of disease progression in 74 Panamanian HIV-positive patients and 50 HIV-negative healthy individuals. Total lymphocyte and CD4(+)-cell counts for AIDS patients (1,451 +/- 811 cells/microliters, P < 0.001, and 238 +/- 392 cells/microliters, P < 0.0001, respectively and asymptomatic patients (2,393 +/- 664 cells/microliters, P > 0.05, and 784 +/- 475 cells/microliters, P < 0.001, respectively) were lower than those observed for healthy subjects (2,596 +/- 631 cells/microliters and 1,120 +/- 296 cells/microliters, respectively). The levels of beta 2-microglobulin and IgA in serum were significantly elevated in patients with AIDS (5.7 +/- 3.6mg/liter, P < 0.001, and 541 +/- 265 mg/dl, P < 0.0002, respectively) and asymptomatic infected subjects (3.4 +/- 2.1 mg/liter, P = 0.001, and 436 +/- 216 mg/dl, P < 0.0001, respectively) compared with the levels in healthy subjects (2.2 +/- 0.7 mg/liter and 204 +/- 113 mg/dl, respectively). Nonstatistically significant differences (P > 0.05) for concentrations of p24 antigen between asymptomatic infected patients (29 +/- 13 pg/ml) and AIDS patients (40 +/- 23 pg/ml) were observed. Total lymphocyte counts of 1,750 cells/microliters or less, CD4 counts of 200 cells/microliters or less, beta 2-microglobulin concentrations in serum of 4 mg/liter or higher, concentrations of IgA in serum of 450 mg/dl or higher, and the presence in serum of p24 antigen were correlated with elevated risks for developing AIDS. Monitoring both total lymphocytes and beta 2-microglobulin identified 91% of the AIDS patients; these assays may allow reductions in the annual number of CD4(+)-cell evaluations and the costs associated with monitoring both total lymphocytes and beta 2-microglobulin identified 91% of the AIDS patients; these assays may allow reductions in the annual number of CD4(+)-cell evaluations and the costs associated with monitoring the immune status of HIV-positive patients.  相似文献   
295.
A case is reported of a 43-year-old man who presented prostatitis and hepatitis due to Brucella melitensis. His symptoms were icterus, weakness, anorexia, fever, and urinary discomfort. Physical examination revealed icterus and hepatosplenomegaly. Lymphomonocytosis, elevated erythrocyte sedimentation rate and abnormal liver functions had been detected in laboratory tests. Brucella melitensis was isolated from prostatic fluid and blood cultures.  相似文献   
296.
Familial hypercholesterolemia is an autosomal dominant inherited condition characterized by a mutation in the low-density lipoprotein receptor (LDLR) gene. A database has been set up on the World Wide Web for mutations in the LDLR gene.  相似文献   
297.
298.
根据彩色AC-PDP放电机理的物理模型,提出了基于粒子流连续性方程和泊松方程的一维彩色AC-PDP放电单元和数值计算模型。然后由其数值解描述了放电过程和电子,各种离子及中性粒子浓度的时空分布,放电单元的放电电流随时间变化以及电场强度的时空分布。  相似文献   
299.
Food poisoning bacteria, Staphylococcus aureus, Salmonella, Yersinia enterocolitica and Aeromonas hydrophila, were inoculated onto imitation crablegs and flaked crab. Inoculated samples were incubated at 0°C, 5°C, 10°C, and 15°C. Staphylococcus, Salmonella, and Aeromonas increased at 15°C and 10°C. but not at the two lower temperatures. Yersinia grew at the four temperatures tested. The rapid growth at these temperatures clearly indicated that the pathogens could be potential hazards if the products were contaminated and subjected to temperature abuse after leaving the processing plants.  相似文献   
300.
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