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81.
Cases in which there are more than three copies of a sex chromosome, and rarely of an autosome, have been reported, but to our knowledge hexasomy has never been described except in tissue undergoing neoplastic change. This report describes a female infant with multiple malformations in whom we found a mosaic hexasomy 21. This was first detected in amniotic fluid cells and subsequently in skin fibroblasts. 相似文献
82.
In vivo synthesis and utilization of arginine in the rat 总被引:3,自引:0,他引:3
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85.
Associations between Mycoplasma genitalium,Chlamydia trachomatis and pelvic inflammatory disease 总被引:6,自引:0,他引:6
Simms I Eastick K Mallinson H Thomas K Gokhale R Hay P Herring A Rogers PA 《Journal of clinical pathology》2003,56(8):616-618
OBJECTIVE: To evaluate the association between Mycoplasma genitalium, Chlamydia trachomatis, and pelvic inflammatory disease (PID) METHODS: A case-control methodology was used. Swab eluates were processed using the QIAamp DNA mini kit. Polymerase chain reaction (PCR) for M genitalium was carried out using a real time in-house 16S based assay. An endocervical swab was taken and tested for the presence of C trachomatis (ligase chain reaction, Abbott Laboratories), and a high vaginal swab was taken and tested for the presence of Neisseria gonorrhoeae and bacterial vaginosis. RESULTS: Of the PID cases 13% (6/45) had evidence of M genitalium infection compared to none of the controls (0/37); 27% (12/45) of the cases had C trachomatis infection compared to none of the controls; and 16% (7/45) of cases only had serological evidence of C trachomatis infection compared to 5% (2/37) of controls. Cases were more likely to present with M genitalium and/or C trachomatis than controls (p<0.001). CONCLUSIONS: This study indicates that there may be an association between M genitalium and PID, and that this relation is largely independent of C trachomatis. Future studies need to investigate the pathological basis of the relation between M genitalium and PID using samples from women with PID diagnosed using laparoscopy and endometrial biopsy. Little is known about the epidemiology of M genitalium: large scale epidemiological investigations are needed to determine the prevalence, incidence, and factors associated with this emerging infection. 相似文献
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87.
Norepinephrine and amino acids in prepyriform cortex of rats fed imbalanced amino acid diets 总被引:1,自引:0,他引:1
Monoamines and amino acids were measured in anterior prepyriform cortex (PPC) and anterior cingulate cortex (CC) of male Sprague-Dawley rats after they were offered basal, imbalanced (IMB) or corrected amino acid diets, limited in threonine (THR) or isoleucine (ILE). In the THR study, brains were taken after 2.5 hr of feeding, when intake of THR-IMB was just depressed. In the ILE study the brains were taken after 3.5 hr on ILE-IMB, a less severely imbalanced ration, before the onset of food intake depression. The PPC has been shown to be involved in the acute response of animals to imbalanced amino acid diets. In the PPC from the IMB diet groups, NE was reduced by 30%, but the other monoamines were unchanged. In CC, an area involved in the adaptive, but not the acute feeding response to imbalanced diets, the monoamines were unchanged in the IMB diet groups. In both studies, in both tissues, the limiting amino acids were decreased in the IMB groups, although the decrease of ILE in the CC failed to reach significance. The remaining indispensable amino acids, added to create the imbalance, were slightly reduced in the THR-IMB group, but not in the ILE-IMB group in both tissues. Thus, the amino acid patterns were altered in the PPC and CC, as they are in whole brains from animals fed imbalanced amino acid diets. These results also suggest that the concentration of NE in the PPC may be associated with the initial food intake response of animals to imbalanced amino acid diets. 相似文献
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Hoang MP Rogers BB Dawson DB Scheuermann RH 《American journal of clinical pathology》1999,111(5):655-659
Human herpesviruses are associated with morbidity and mortality in persons with compromised immune systems, including patients infected with human immunodeficiency virus (HIV). To investigate the basis for this association, the levels of all 8 human herpesviruses (herpes simplex virus, types 1 and 2, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, and human herpesvirus 6, human herpesvirus 7, and human herpesvirus 8) were measured with the quantitative polymerase chain reaction (PCR). Viral DNA was measured in the whole blood of 20 HIV-infected patients and compared with levels in 20 healthy blood donors. There was no significant difference in the frequency of virus detection of the 8 human herpesviruses between HIV-infected patients and healthy adults. These results indicate that HIV infection is not associated with a general increase in the circulating levels of human herpesviruses, and suggest that quantitative PCR analysis is superior to qualitative PCR analysis for detection of clinically relevant disease in HIV-infected patients. 相似文献
90.
Joseph Rogers Michael A. Silver William J. Shoemaker Floyd E. Bloom 《Neurobiology of aging》1980,1(1):3-11
A within-subjects design was used to assess age changes in cerebellar Purkinje neurons. Four groups of naive male Sprague-Dawley rats, aged 3, 10, 20, and 28 months, underwent single cell recording for electrophysiological assessment of Purkinje cell firing patterns, followed by perfusion for glyoxylic acid induced catecholamine fluorescence. Cerebellar sections were photographed first by fluorescence microscope for catecholamines, and 2–3 weeks later for quantification of lipofuscin autofluorescence. Finally, these same tissues were treated with cresyl violet and photographed a third time to permit quantitative estimates of age changes in the number of Nissl staining Purkinje neurons. Electrophysiological studies revealed significant effects of age on a number of Purkinje cell firing parameters: in particular, increasing numbers of aberrant, very slow-firing cells were encountered in older animals. These cells showed normal climbing fiber mediated burst activity, but spontaneous simple spike firing rates 3–5 times less than normal. Rats exhibiting the highest numbers of such abnormal cells also exhibited the poorest Nissl staining. Conversely, good Nissl staining of Purkinje neurons in an old rat was a reliable predictor of relatively normal Purkinje cell firing. Lipofuscin was found to accumulate measurably in Purkinje neurons by 20 months of age, and to increase significantly thereafter. Deposition of the substance occurred almost exclusively at the apical pole of the soma. Our data suggest, however, that accumulation of lipofuscin in Purkinje neurons, as well as its reported accumulation in the inferior olive, is not a primary cause of electrophysiological dysfunction. There was no apparent age change in glyoxylic acid induced catecholamine fluorescence nor, in separate pharmacological studies, could any senescent alteration in cerebellar catecholamine levels be found. 相似文献