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991.
An essential component of the family planning of a newly married couple is determining not only the number of children but also the spacing of births. AIM: To study the preferences of newly married couples of Bulgarian ancestry from Plovdiv for between-birth intervals and factors that have effect on them. METHODS: The present transversal study was designed to investigate family planning in young families of Bulgarian origin from the town of Plovdiv at the time of submission of documents for state registration of marriage. The primary sociological information was gathered by a direct individual inquiry of 384 families. The data were compared with data from a similar study performed in 1995. RESULTS: Only one third of the women are willing to have a child immediately after marriage. Men prefer this to happen 1.61 +/- 0.07 year after the marriage while women favour longer protogenetic interval--1.84 +/- 0.06. The opinion of the spouses inquired about the age of women at last birth shows that there is statistically significant increase in this variable from 34.89 +/- 0.29 years in 1995 to 36.33 +/- 0.32 years in 2000. No statistically significant difference was found between the protogenetic intervals of 2000 and 1995. CONCLUSIONS: The increased age at marriage, the postponement of childbirth and increase in the anticipated age of last birth supports the thesis that the Bulgarian family type has undergone changes towards the family type characteristic for the countries in Western Europe. 相似文献
992.
Exposure to Chlamydia pneumoniae infection and progression of age-related macular degeneration 总被引:2,自引:0,他引:2
Robman L Mahdi O McCarty C Dimitrov P Tikellis G McNeil J Byrne G Taylor H Guymer R 《American journal of epidemiology》2005,161(11):1013-1019
Recent studies have found an association between exposure to Chlamydia pneumoniae infection and risk of age-related macular degeneration (AMD). To assess a potential risk of AMD progression posed by exposure to C. pneumoniae, the authors reexamined Australian residents in 2001-2002 who were aged 51-89 years with early AMD at baseline (1992-1995). Examination included macular photography and an enzyme-linked immunosorbent assay to determine antibody titers to the elementary bodies from C. pneumoniae AR39. AMD progression was assessed quantitatively, using both coarse and fine progression steps following an international classification for AMD grading, and also qualitatively, by side-by-side comparison of baseline and follow-up macular photographs. Serologic data were available for 246 of 254 (97%) subjects. AMD progression was associated with a higher antibody titer. After adjustment for age, smoking, family history of AMD, history of cardiovascular diseases, and source study, the subjects in the upper tertiles of antibody titers were 2.1 (95% confidence interval: 0.92, 4.69), 2.6 (95% confidence interval: 1.24, 5.41), and 3.0 (95% confidence interval: 1.46, 6.37) times more at risk of progression than those in the lowest tertile, using three definitions of progression, respectively. The fact that seroreactivity to C. pneumoniae was independently associated with the risk of AMD progression suggests that C. pneumoniae infection may be an additional risk factor for AMD progression. 相似文献
993.
Gene expression profiles in prostate cancer: association with patient subgroups and tumour differentiation 总被引:3,自引:0,他引:3
Halvorsen OJ Oyan AM Bø TH Olsen S Rostad K Haukaas SA Bakke AM Marzolf B Dimitrov K Stordrange L Lin B Jonassen I Hood L Akslen LA Kalland KH 《International journal of oncology》2005,26(2):329-336
Prostate carcinoma is the most common cancer of western men and is a markedly heterogeneous disease. The aim of this study was to identify signatures of differentially expressed genes in prostate cancer using DNA microarray technology, evaluating expression profiles in matched pairs of benign and malignant tissue. Samples were collected from 33 radical prostatectomies, and 52 specimens were included, representing 29 histologically verified primary tumours, 19 paired samples of malignant and benign tissue, and 4 non-paired benign tissue samples. Microarray analysis was performed using an expanded sequence verified set of 40,000 human cDNA clones, revealing several genes with significant differences between malignant and benign tissue, including recently reported genes like alpha-methylacyl-CoA racemase (AMACR) and hepsin, as well as genes relevant for tumour development and progression. Leave out cross validation (LOCV) test correctly predicted tumour or benign tissue in 47 (90.3%) out of 52 cases, significantly better than cross validation tests using randomly permuted tissue labels. Unsupervised clustering analysis revealed 3 distinct patient clusters significantly associated with Gleason score, and high grade tumours (Gleason score >/=7) accumulated in cluster 1 (C1). Gene expression profiles correctly predicted 100% of tumour samples segregating to C1, as also validated by LOCV. Gene expression profiles were analysed in filtered and floored datasets with similar results, and a pair-wise design was also tested. Gene expression profiles provided tumour clusters linked to differentiation, and revealed novel markers relevant for molecular classification, grading and therapy of prostate cancer. 相似文献
994.
995.
Melnikova L Juge F Gruzdeva N Mazur A Cavalli G Georgiev P 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(41):14806-14811
Chromatin insulators or boundaries are proposed to structure the chromatin fiber into functionally independent domains by promoting the formation of chromatin loops. These elements can block the communication between an enhancer and a gene when placed between them. Interestingly, it has been previously observed that two tandem copies of the Drosophila Su(Hw) insulator abolish this enhancer-blocking activity, presumably through pairing. This bypass effect has not been described with other insulators, however. In this report, we show that the insertion of binding sites for the GAGA factor (GAF) between an enhancer and the Su(Hw) insulator allows bypassing of the insulator. This bypass relies on the activity of both the GAF protein and the Mod(mdg4)-67.2 protein, a factor required for Su(Hw) insulator activity. We show that these two proteins interact in vitro and in vivo, providing molecular evidence of pairing between the GAF sites and the Su(Hw) insulator. Finally, we show that placing the Mcp boundary together with the Su(Hw) insulator between an enhancer and a promoter leads to bypass, again in a GAF- and Mod(mdg4)-dependent manner. Our data provide direct evidence that heterologous insulators can be bypassed by distal enhancers and identify the interaction between GAF and Mod(mdg4) as a possible means to regulate insulator activity. 相似文献
996.
A wide range of operations are used today for morbid obesity. Adjustable gastric banding (AGB) is one of the most widespread.
Numerous complications after AGB are known, namely gastric perforation, band slippage, penetration of the band into stomach,
port disconnection, port-site infection, etc. The authors present a case of small bowel obstruction caused by the intra-abdominal
silicone tube of the gastric band in a woman with AGB performed 9 years before, with a very good result and considerable weight
loss. She was operated as an emergency, and part of the terminal ileum was found incarcerated around and between the silicone
tube and the anterior abdominal wall. Bowel resection for intestinal necrosis, with terminal ileostomy, was performed, followed
1 month later by an end-to-end ileo-ileal anastomosis. The patient recovered without sequelae. 相似文献
997.
Recent human studies suggested a supportive influence of regular nocturnal sleep on immune responses to experimental infection (vaccination). We hypothesized here that sleep could ease such responses by shifting the balance between T helper 1 (Th1) and T helper 2 (Th2) cytokine activity towards Th1 dominance thereby favoring cellular over humoral responses to infection. We compared the Th1/Th2 cytokine balance in 14 healthy men during regular nocturnal sleep (between 23:00 and 07:00 h) and while remaining awake during the same nocturnal interval, in a within-subject cross-over design. Blood was collected every 2 h. Production of T cell derived cytokines--interferon-gamma (IFN-gamma), interleukin-2 (IL-2), interleukin-4 (IL-4), and tumor necrosis factor-alpha (TNF-alpha)--was measured at the single cell level using multiparametric flow cytometry. Also, several immunoactive hormones--prolactin, growth hormone (GH), thyroid stimulating hormone (TSH), cortisol, and melatonin--were measured, the release of which is known to be regulated by sleep. Compared with wakefulness, early nocturnal sleep induced a shift in the Th1/Th2 cytokine balance towards increased Th1 activity, as indicated by an increased (p <.05) ratio of IFN-gamma/IL-4 producing T helper cells. However, the Th1 shift was only of moderate size and replaced by Th2 dominance during late sleep (p <.05). It could be mediated via release of prolactin and GH which both were distinctly increased during sleep (p <.001). Though unexpected, the most pronounced effect of sleep on T cell cytokine production was a robust decrease in TNF-alpha producing CD8+ cells probably reflecting increased extravasation of cytotoxic effector and memory T cells. 相似文献
998.
Dimitrov S Koleva Y Schultz TW Walker JD Mekenyan O 《Environmental toxicology and chemistry / SETAC》2004,23(2):463-470
The present study proposes a generic interspecies quantitative structure-activity relationship (QSAR) model that can be used to predict the acute toxicity of aldehydes to most species of aquatic organisms. The model is based on the flow-through fathead minnow (Pimephales promelas) 50% lethal concentration (LC50) data combined with other selected fish acute toxicity data and on the static ciliate (Tetrahymena pyriformis) 50% inhibitory growth concentration (IGC50) data. The toxicity of Schiff-base acting aldehydes was defined using hydrophobicity, as the calculated log 1-octanol/water partition coefficient (log Kow), and reactivity, as the donor delocalizability for the aldehyde O-site (D(O-atom)). The fish model [log 1/LC50 = -2.503(+/-1.950) + 0.480(+/-0.052) log Kow + 18.983(+/-6.573) D(O-atom), n = 62, r2 = 0.619, s2 = 0.241, F = 48.0, Q2 = 0.587] compares favorably with the ciliate model [log 1/IGC50 = -0.985(+/-1.309) + 0.530(+/-0.044) log Kow + 11.369(+/-4.350) D(O-atom), n = 81, r2 = 0.651, s2 = 0.147, F = 72.9, Q2 = 0.626]. The fish and ciliate surfaces appear to be parallel, because they deviate significantly only by their intercepts. These observations lead to the development of a global QSAR for aldehyde aquatic toxicity [log E(-1) = bE(Organism) + 0.505(+/-0.033) log Kow + 14.315(+/-3.731) D(O-atom), n = 143, r2 = 0.698, s2 = 0.187, S2(Fish) = 0.244, S2(Ciliate) = 0.149, F = 98, Q2 = 0.681]. The general character of the model was validated using acute toxicity data for other aquatic species. The aldehydes global interspecies QSAR model could be used to predict the acute aquatic toxicity of untested aldehydes and to extrapolate the toxicity of aldehydes to other aquatic species. 相似文献
999.
Mukesh BN Dimitrov PN Leikin S Wang JJ Mitchell P McCarty CA Taylor HR 《Ophthalmology》2004,111(6):1176-1182
PURPOSE: To describe the 5-year incidence of age-related maculopathy (ARM) and the progression of the early stages of ARM lesions in Melbourne, Australia. DESIGN: Population-based cohort study. PARTICIPANTS: A total of 3271 participants aged 40 years and older from Melbourne, Victoria, Australia. MAIN OUTCOME MEASURES: The 5-year incidence and progression of ARM lesions. METHODS: Participants were recruited through a cluster random sampling from 9 urban clusters. Baseline examinations were conducted from 1992 through 1994, and the follow-up data were collected from 1997 through 1999. Presence of ARM lesions was graded from color stereo fundus photographs according to the International Classification and Grading System. RESULTS: The overall cumulative 5-year incidence of age-related macular degeneration (AMD) was 0.49% (95% confidence interval [CI], 0.2-0.8) and that of early ARM was 17.3% (95% CI, 8.7-26.0). The incidence of all ARM lesions increased with age (all P<0.001). The 5-year incidence of AMD was 0%, 0.69%, 1.7%, and 6.3% and that of early ARM was 13%, 22.7%, 29.8%, and 20% for participants aged 60 years and younger, aged 60 to 69 years, aged 70 to 79 years, and aged 80 years and older at baseline, respectively. People with soft indistinct drusen with pigmentary abnormalities had a 9.5 times (95% CI, 1.9-45.6) higher risk of developing AMD compared with people with soft drusen or pigmentary abnormalities. After adjusting for age, people with unilateral early ARM at baseline were 3 times (95% CI, 0.98-8.0) as likely to have early ARM in their second eye when compared with people with no ARM in both eyes. CONCLUSIONS: These data suggest that 1 in 3 persons aged 70 years or older will have ARM lesions over a 5-year period and that the disease will progress to a more severe form after the age of 80 years. The presence of soft indistinct drusen with pigmentary abnormalities significantly increased the risk for development of AMD. 相似文献
1000.
A case of placenta previa/accreta focalis was diagnosed at 29 weeks gestation in a 40 year-old patient using color Doppler ultrasound. A picture of intense blood flow within the placental sonolucent spaces, with vessels crossing from the placenta into the uterine wall was evident. A Cesarean section was performed. The macroscopic examination of the uterus during the operation revealed a focal invasion of the placental villi throughout the myometrium. 相似文献