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The dental ages of 1286 (674 males and 612 females) Egyptian children born and grown up in a community with naturally occurring overfluoride ions in the drinking water (more than the optimal level) in Matrouh Governorate, were compared with the Egyptian standards of the fluoride deficient area of the same socioeconomic level. The age ranged from 8 years to 14 years and 6 months. The results of the present study revealed that the communal water supply with a fluoride ions concentration more than optimal level has no long term effect on the dental age, as judged from the tooth emergence of the growing children.  相似文献   
103.
Following the first report of avian Giardia infection in Australia, isolates of the parasite recovered from naturally infected straw-necked ibis (Theskiornis spinicollis) were characterized using median body morphology, scanning electron microscopy, multilocus enzyme electrophoresis, random amplified polymorphic DNA (RAPD), and small subunit ribosomal RNA (SSU-rRNA) analyses. Results were compared with Giardia from other birds and mammals, and the extent of genetic diversity between a range of ibis isolates collected in Western Australia was determined. The ibis isolates of Giardia were genetically relatively homogeneous, which is in contrast to the extensive genetic heterogeneity often displayed by mammalian Giardia isolates. Morphologically, Giardia from ibis were similar to Giardia ardeae although they differed genetically and by the fact that the ibis isolates could not be established in in vitro culture. Sequence data of the DNA coding for the SSU-rRNA found a 96% homology between the ibis isolates from Western Australia and G. ardeae, suggesting that they represent distinct strains of the same species. In contrast, the ibis isolates were genetically and morphologically very different than Giardia duodenalis and Giardia muris from mammals.  相似文献   
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This prospective cohort study was designed to test whether a distinct fatigue syndrome existed after the onset of glandular fever. Two hundred and fifty primary care patients, with either glandular fever or an ordinary upper respiratory tract infection (URTI) were interviewed three times in the 6 months after the clinical onset of their infection. At each interview a standardized psychiatric interview was given and physical symptoms were assessed. There were 108 subjects with and Epstein-Barr virus (EBV) infection; 83 subjects had glandular fever not caused by EBV and 54 subjects had an ordinary URTI. Five subjects were excluded because they had no evidence of an infection. Principal components analyses of symptoms supported the existence of a fatigue syndrome, particularly in the two glandular fever groups. The addition of symptoms not elicited by the standard interviews gave the full syndrome. This included physical and mental fatigue, excessive sleep, psychomotor retardation, poor concentration, anhedonia, irritability, social withdrawal, emotional lability, and transient sore throat and neck gland swelling with pain. A fatigue syndrome probably exists after glandular fever.  相似文献   
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Corticosterone increases with aging but pregnenolone, dehydroepiandrosterone, and testosterone decrease. The marked decrease in hormones that occurs with aging may contribute to the age-related deficit in learning and memory. Administration of these hormones after training was found to improve long-term memory processing in normal young mice. SAMP8 (P8) mice show an age-related loss of learning and memory for a variety of tasks whereas age-matched control mice of the closely related SAMR1 (R1) strain do not. In this study, we found an age-related decrease in serum testosterone levels of 71% between P8 mice 4 and 12 months of age, but only a 26% decrease between R1 mice of the same ages. The difference between the P8 mice was significant (p < 0.01) and the difference between the R1 mice was not. The decrease in testosterone in 12-month-old P8 mice was not accompanied by gross morphological change in the testes. A SC testosterone implant, sufficient to increase plasma testosterone levels to 414 +/- 25 ng/dl, alleviated impaired learning and memory of a foot shock avoidance task in P8 mice. Castration of 4-month-old P8 mice did not produce a deterioration in learning and memory, indicating that low levels of testosterone per se are not responsible for the impairment seen in 12-month-old P8 mice. This suggests that impaired cognitive functioning of the older P8 mice was due to an interaction of aging and reduced testosterone levels.  相似文献   
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Advances in the knowledge of the molecular genetics of Gaucher disease has made diagnosis more certain. Carrier detection in kindreds in which the responsible mutation has been defined is completely reliable now. Coupled with enzymatic assays, the diagnostic capabilities are greater than before. Use of these methods provides important information to individuals at risk and allows them to make critical decisions. The new, simplified methods reviewed in this article permit the molecular diagnosis of the disease and carrier stage of large numbers of samples within 1 week.  相似文献   
110.
In light of recent studies showing that prostate-specific antigen (PSA) complexes with certain blood proteins, we studied the effects of acute-phase reactants and alpha 2-macroglobulin (A2MG) on serum concentrations of PSA. Serum samples were obtained from 419 men admitted to an acute-care facility. Various acute-phase reactants-including C-reactive protein, alpha 1-acid glycoprotein, alpha 1-antitrypsin, and alpha 1-antichymotrypsin-and A2MG were measured with a Beckman Array analyzer in parallel with determinations of PSA concentrations by two methods, the Hybritech Tandem RIA and the Abbott PSA IMx. Evaluation by Spearman rank correlation revealed a significant negative correlation of A2MG with PSA values (P < 0.01) and (as expected) a positive correlation of age with PSA values (P < 0.001). The former correlation suggests the possibility that patients with high serum concentrations of A2MG may give falsely decreased results for PSA concentrations in serum.  相似文献   
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