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61.
The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states.  相似文献   
62.
Infective endocarditis caused by zoonotic microorganisms is an uncommon clinical entity. A 55-year-old man was diagnosed with endocarditis due to Capnocytophaga canimorsus, a commensal bacterium contained in the saliva of dogs, that involved the aortic and tricuspid valves and was complicated by a para-aortic valve abscess and aorta-to-right atrial fistula. The patient was successfully treated with antibiotic therapy and surgical intervention. C canimorsus endocarditis should be considered in patients with culture-negative endocarditis, particularly in immunosuppressed, asplenic or alcoholic individuals who have recently suffered a dog bite or have had close contact with dogs.  相似文献   
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CJ Hobbs  JM Wynne  AJ Thomas 《Archives of disease in childhood》1995,73(5):465-9; discussion 469-71
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management.  相似文献   
65.
Little objective evidence has been published to support the claim that constipation is an important contributory factor in recurrent urinary tract infection (UTI) in childhood. Using a radiological scoring system, two observers assessed faecal loading from abdominal radiographs of children with proved UTIs. There was a significant increase in the degree of faecal loading in children with UTI when compared with controls (r = 0.237). This difference was mainly accounted for by girls with recurrent (greater than five) UTIs. This study confirms an association between recurrent UTI and faecal loading. Further studies are needed to establish if there is a causal relationship and benefits from treatment.  相似文献   
66.

Background  

Previous epidemiological studies have inconsistently shown a modestly increased breast cancer risk associated with hormone replacement therapy (HRT). Limited information is available about different formulations - particularly concerning different progestins.  相似文献   
67.

Background  

The Licensing Act 2003 (The Act) was implemented on the 24th November 2005 across England and Wales. The Act allowed more flexible and longer opening hours for licensed premises. We investigated the effect of The Act on alcohol related attendances to an inner city emergency department in Birmingham, UK.  相似文献   
68.
Extralobar pulmonary sequestration was found in a newborn premature infait that presented with non-immune hydrops fetalis, massive bilateral hydrothorax and polyhydramnios in utero. The baby died of severe respiratory insufficiency 15 h after birth. Postmortem examination revealed distended lymphatic vessels in the sequestered lung tissue probably due to impeded lymph drainage. We suggest that not extralobar pulmonary sequestration itself but a subsequent massive unilateral hydrothorax due to severe obstruction of lymph drainage was the cause of the non-immune hydrops fetalis, pulmonary hypoplasia and polyhydramnios. If these symptoms are diagnosed before delivery, a search for extralobar pulmonary sequestration is indicated.  相似文献   
69.
70.
To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.  相似文献   
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