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91.
Variation in the levels of sex-steroid hormones results from differences in developmental conditions, adult lifestyle, and genetic polymorphism. Genes involved in sex-steroid biosynthesis have been implicated to influence levels of hormones in premenopausal women, but the results were inconclusive. We tested variation among women in levels of salivary estradiol (E(2)) corresponding to CYP17 genotypes. CYP17 encodes cytochrome P450c17alpha, which mediates two enzymes important in E(2) synthesis. In contrast to the earlier studies that relied on one or a few samples for assessing the E(2) levels of an individual woman, our study is based on daily collected saliva samples for one entire menstrual cycle. Sixty Polish women, ages 24 to 36 years, with regular menstrual cycles and no reported fertility problems participated in the study. Women with A2/A2 genotype had 54% higher mean E(2) levels than women with A1/A1 genotype (P = 0.0001) and 37% higher than women with A1/A2 genotype (P = 0.0008). Heterozygous A1/A2 women had 13 % higher E(2) levels than homozygous A1/A1 women (but this difference was significant only in a nonparametric test). Levels of E(2) during the day with highest E(2) (day -1) were 72% higher in A2/A2 compared with A1/A1 (P = 0.01) and 52 % higher compared with A1/A2 (P = 0.03). Our results suggest that CYP17 genotype may serve as a biomarker of endocrine function in women of reproductive age. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2131-5).  相似文献   
92.
DNA alkylating agents such as 1, 2-dimethylhydrazine (SDMH)and azoxymethane (AOM) are potent carcinogens and are widelyused to induce colon tumors in experimental animals. However,standard bacterial mutagenesis assays have failed to detectthe mutagenic effects of these chemicals. Using derivativesof a set of Escherichia coli test strains developed by Cupplesand Miller (Proc. NatL Acad. Set USA, 86, 5345, 1989), we havedemonstrated that under two conditions, SDMH and AOM inducedpoint mutations by several-fold in a dose-dependent manner:(i) of six possible base substitutions, they only induced GC  相似文献   
93.
A low level of physical activity and decreased exercise capacity are independent risk factors for cardiovascular and all-cause mortality. The assessment of the level of physical activity and its improvement following preventive procedures is methodologically difficult. In population studies, subjective methods, such as questionnaires, activity records and other somewhat imperfect measures (accelerometers, pedometers, and pulse monitors), are used. Direct and especially indirect assessment of physical capacity with exercise tests has become increasingly more accessible and cheap. Both methods have been proved to have high prognostic value. Assessment of physical capacity enables objectification of information on the level and effects of a subjects physical activity acquired via a questionnaire. Taking into account the above-mentioned issues, the role of the assessment of exercise capacity and its improvement is not adequately appreciated. Routine evaluation of exercise capacity has not been included in the current statements on epidemiology and prevention, even in those with an increased Framingham or SCORE risk index in whom low exercise tolerance has been proved to have an unfavorable influence on prognosis. The importance of an increase in the level of physical activity resulting in an improvement in exercise capacity in different population groups should be verified in the near future, but in our opinion there is indirect but strong evidence that actions to improve exercise capacity should become the main goals in the prevention of cardiovascular and all-cause mortality, such as cessation of cigarette smoking, body weight reduction, correction of lipid and carbohydrate metabolism disturbances, and a decrease in blood pressure.  相似文献   
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Use of optical coherence tomography in myopia   总被引:1,自引:0,他引:1  
PURPOSE: To measure retinal thickness and retinal nerve fiber layer thickness using optical coherence tomography in patients with myopia. PATIENTS AND METHODS: Thirty patients (13 girls and 17 boys) 14 to 18 years old were included in the study. The control group consisted of 15 patients. Each patient was subjected to routine ophthalmic investigations, which included the assessment of visual acuity for near and distant objects, autorefractometry, measurement of intraocular pressure, biometry, and assessment of the static visual field. The foveal retinal thickness and the peripapillary nerve fiber layer thickness were measured using optical coherence tomography. RESULTS: The mean foveal retinal thickness was 231.0 microm in eyes with low myopia, 218.0 microm in eyes with medium myopia, and 178.0 microm in eyes with high myopia. The mean thickness of the retinal nerve fiber layer was 150.0 microm, 140.0 microm, and 152.0 microm, respectively. Statistically significant differences were revealed between patients with high myopia and the control group. CONCLUSION: Optical coherence tomography can be employed to assess the retinal thickness and thus facilitate the detection of the evolution of alterations in myopia.  相似文献   
97.
Addison-Biermer's anaemia is an autoimmune disease. It may coexist with other auto-aggressive diseases, precede them or join the other existing autoimmune diseases. It most often accompanies the Hashimoto disease but also may coexist polyglandular autoimmune syndrome (PGA). Three types of PGA are distinguished: PGA1--Blizzard's Syndrome, PGA2--Schmidt's Syndrome, and PGA3. The latter, unlike the remaining ones, is characterized by normal function of adrenal glands. Addison-Biermer's anaemia occurrence may be often difficult to diagnose as coexisting illnesses might ouflage its clinical symptoms. The aim of this paper was to analyse patients with different types of PGA with coexisting Addison-Biermer's anaemia. Group of 24 individuals was analysed: 2 women with PGA1, 10 patients with PGA2, 10 patients with PGA3. In 2 remaining ones PGA was not confirmed. Addison-Biermer's anaemia occurred in 7 patients (2 with PGA2 and 5 with PGA3 syndrome). Decreased concentration of vitamin B12 was diagnosed in 3 individuals among 24 examined patients (1 with type 3 and 2 with type 2), as well in 2 patients with unconfirmed PGA. Addison-Biermer's anaemia was not observed in patients with PGA1. We observed that megaloblastic anaemia occurred characteristic schedule depending on appearance of autoimmune diseases: in PGA2--many years after other immunopathies were found, in PGA3--as first auto-aggressive disease. Our analysis suggests the necessity of detailed check-ups on patients with Addison-Biermer's anaemia, as with time they may develop other diseases, especially hypothyroidism and/or PGA failure. On the contrary, in individuals with thyroid gland diseases and PGA syndromes further checkups should be megaloblastic anaemia-sensitive. In both cases it is important to consider substitutive treatment. The possibility of family coexisting both pernicious anaemia and autoimmune endocrinopathies needs diagnostics of members of the patient's family.  相似文献   
98.
The most common infections in primary immune deficiency disease (PIDD) patients involve encapsulated bacteria, mainly Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae (pneumococcus). Thus, it is important to know the titers of Hib- and pneumococcus-specific antibodies that are present in immune globulin (Ig) intravenous (IGIV) preparations used to treat PIDD. In this study, seven IGIV preparations were tested by enzyme-linked immunosorbent assay and opsonophagocytic activity for antibody titers to the capsular polysaccharides of Hib and five pneumococcal serotypes. Differences in Hib- and pneumococcus-specific antibody titer were observed among various IGIV preparations, with some products having higher- or lower-than-average titers. Opsonic activity also varied among preparations. As expected, IgG2 was the most active subclass of both binding and opsonic activity except against pneumococcal serotype 6B where IgG3 was the most active. This study determines antibody titers against capsular polysaccharides of Hib and pneumococcus in seven IGIV products that have been shown to be effective in reducing infections in PIDD patients. As donor antibody levels and manufacturing methods continue to change, it may prove useful from a regulatory point of view to reassess IGIV products periodically, to ensure that products maintain antibody levels that are important for the health of IGIV recipients.  相似文献   
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100.
The loss of chromosome Y has often been observed in human solid tumors. This chromosome aberration has been proposed as one of genetic changes predisposing men to squamous cell carcinoma of the head and neck (SCCHN). In this study, using cytogenetic analysis and fluorescence in situ hybridization we analyzed: 16 cell lines derived from primary and recurrent SCCHN, a group of 22 samples derived from of previously analyzed primary larynx tumors and their corresponding metastases and a group of eight multiple primary tumors received from two different locations within the head and neck region of the same patients. In the majority of analyzed cell lines we found both loss of chromosome Y and SRY-probe signals (68.7% of samples) and these were nearly always found in the analyzed metaphases. The whole chromosome Y was usually lost, but in two cases we observed translocation of this chromosome to chromosomes 1, 3 and 17. Among all primary tumors, 14 (63.6%) and 15 of their metastases (68.2%) showed a loss of chromosome Y in a prevailing number of analyzed nuclei. Also, in the group of primary tumors and second primary tumors, all samples had a loss of the chromosome Y in the majority of analyzed nuclei.  相似文献   
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