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991.
S K Hwang  B M Park 《Orthopedics》1991,14(7):809-812
Forty immature and 40 mature rabbits which received periosteal resection from the proximal metaphyses or diaphyses of tibiae were evaluated for the occurrence of osteochondromas at the sites of periosteal defects. Thirteen of 20 immature tibiae with the periosteal defects at their proximal metaphyses showed osteochondromas covered by hyaline cartilage caps. We assume that the occurrence of osteochondroma at the metaphyseal region of growing long bone, where the periosteal defects were made, is due primarily to a decrease in the power of the periosteum to control the circumferential growth of the metaphysis, and is due secondarily to an abnormal proliferation of cartilage progenitors located in Ranvier's groove.  相似文献   
992.
993.
The expected quality-adjusted survival (QAS) for an index population with a specific disease can be estimated by summing the product of the survival function and the mean quality of life function of the population. In many follow-up studies with heavy censoring, the expected QAS may not be well estimated due to the lack of data beyond the close of follow-up. In this paper, we first created a reference population from the life tables of the general population according to the Monte Carlo method. Secondly, we fitted a simple linear regression line to the logit of the ratio of quality-adjusted survival functions for the index and reference populations up to the end of follow-up. Finally, combining information on the reference population with the fitted line, we predicted the expected quality-adjusted survival curve beyond the follow-up period for the index population. Simulation studies have shown that the simple Monte Carlo estimation procedure is a potential approach for estimating expected QAS and the survival function beyond the follow-up with a certain degree of accuracy.  相似文献   
994.
995.
Pityriasis alba (PA) is a common benign disease, characterized by hypopigmented macules or patches on the face, usually seen in children. However, two uncommon variants exist, a pigmenting type and an extensive type. Extensive PA is rare. The lesions tend to be less scaly, more persistent, more generalized, more symmetrical, and more frequently seen over the trunk and less so over the face. We report a child who had extensive PA lesions.  相似文献   
996.
997.
This report describes the color and pulsed Doppler US findings of penile Mondor's disease. The pulsed Doppler US findings of penile Mondor's disease have not been previously published, so we report here for the first time on the cavernosal arterial flow signal pattern of penile Mondor's disease. Penile Mondor's disease is rare disease that's characterized by thrombosis in the dorsal vein of the penis. The previous reports on penile Mondor's disease are concerned with the color Doppler US finding without the flow signals in this area, but these findings are insufficient to understand the hemodynamics in penile Mondor's disease. We report for the first time on a cavernosal artery flow signal pattern of low peak systolic velocity and high-resistance.  相似文献   
998.
Syphilitic keratoderma is a rare cutaneous manifestation of secondary syphilis, characterized by symmetrical and diffuse hyperkeratosis of the palms and soles. In addition, no cases of syphilitic keratoderma and uveitis have been reported in the dermatologic literature. A 69-year-old woman presented with steroid-resistant hyperkeratotic patches on the palms and soles and uveitis for 4 months. As steroid-resistant uveitis must be evaluated for syphilis, viral infections, and autoimmune diseases, we ran several laboratory tests and the serologic test for VDRL was reactive (titer; 1:128). After treatment with penicillin G (4 MU, IV every 4 hours for 2 weeks), her skin lesions and visual disturbance were completely resolved. Therefore she was diagnosed as having syphilitic keratoderma and uveitis. Here, we report a rare case of syphilitic keratoderma concurrent with syphilitic uveitis and suggest that evaluation for syphilis may be required when skin lesions and ocular disturbance are resistant to long-term steroid therapy.  相似文献   
999.
Patients with traumatic subdural hygroma (SDG) are at an increased risk of developing chronic subdural hematoma (CSDH). However, the mechanism by which this occurs is still not fully understood. The purpose of this paper is to investigate the clinical characteristics and pathogenesis of CSDH, as well as the relationship between CSDH and SDG. We review the pertinent literature and retrospectively examine a series of cases in which CSDH had been preceded by SDG to understand the natural history and developmental mechanisms of these lesions. We discuss the cases of 24 patients in whom CSDH developed from traumatic SDG between 2001 and 2005. Headache was the most common symptom, and the mean Glasgow Coma Scale score was 14.1. Increases in SDG volume were observed in CT scans of 17 patients, and increased density and volume was observed in five patients. The mean interval between the two diseases was 57.6 days, and 13 patients developed new symptoms after the development of CSDH. The most common symptoms at that time were headache and hemiparesis. All patients underwent an operation, which resulted in good recovery in all but one case. The cycle of persistent SDG, rebleeding, coagulation and fibrinolysis contributes to the development of CSDH from SDG. It is important to understand the natural history of CSDH and carefully follow up patients with head injury, especially if it is associated with SDG, and the potential for the development of CSDH should be considered.  相似文献   
1000.
We assessed the seroprevalence of antibodies to Trypanosoma cruzi among pregnant Hispanic women in Houston. Sera from 2,107 Hispanic and 1,658 non-Hispanic subjects were tested by ELISA for the presence of antibodies to T. cruzi. Twenty-two (0.6%) of 3,765 subjects had sera that were reactive. Seroreactivity was confirmed by hemagglutination assay. Eleven subjects had reactive sera, giving a confirmed seroprevalence of 0.3% (95% CI, 0-1%). Nine sera from Hispanic and two from non-Hispanic women were positive by hemagglutination assay, for a prevalence of 0.4% and 0.1%, respectively, during pregnancy. On the basis of these seroreactivity data, transplacental transmission of T. cruzi could occur in the continental United States. Screening for antibodies to T. cruzi during pregnancy would provide the potential for early intervention in congenital Chagas' disease.  相似文献   
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