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Ossifying fibromyxoid tumor of soft parts   总被引:1,自引:0,他引:1  
Ossifying fibromyxoid tumors (OFT) of soft parts are very rare neoplasms recently described by Enzinger et al. (1). They usually present as well-circumscribed, slow-growing, asymptomatic subcutaneous masses. A characteristic finding is a fibrous capsule and an incomplete peripheral shell of mature bone. Although most cases behave as benign tumors, a high rate of local recurrences have been described. We describe a 43-year-old male with a perianal subcutaneous tumor of 10 years evolution. The histopathology was compatible with OFT. Due to the subcutaneous location of OFF, both the dermatologist and dermatopathologist need to know about this rare tumor.  相似文献   
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Lymnaea cubensis is the vector in a region of distome infection in Trujillo State at more than 1000 m altitude where almost all bovines are infected. A quarter of the molluscs were infected with a mean number of 20 rediae per infected molluc each redia capable of producing 16 cercariae. Prevalence of infection increases with size of molluse and is highest in those 4 to 5 mm long. However, Lymnaea as small as 3 mm produce cercariae and molluscicide treatments should be begun as soon as forms of this size appear.  相似文献   
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We have recently reported isolation of the gene responsible for X- linked Opitz G/BBB syndrome, a defect of midline development. MID1 is located on the distal short arm of the human X chromosome (Xp22. 3) and encodes a novel member of the B box family of zinc finger proteins. We have now cloned the murine homolog of MID1 and performed preliminary expression studies during development. Mid1 expression in undifferentiated cells in the central nervous, gastrointestinal and urogenital systems suggests that abnormal cell proliferation may underlie the defect in midline development characteristic of Opitz syndrome. We have also found that Mid1 is located within the mouse pseudoautosomal region (PAR) in Mus musculus , while it seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a recent acquisition of the M. musculus PAR. Genetic and FISH analyses also demonstrated a high frequency of unequal crossovers in the murine PAR, creating spontaneous deletion/duplication events involving Mid1. These data provide evidence for the first time that genetic instability of the PAR may affect functionally important genes. In addition, we show that MID1 is the first example of a gene subject to X-inactivation in man while escaping it in mouse. These data contribute to a better understanding of the molecular content and evolution of the rodent PAR.   相似文献   
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Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.   相似文献   
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The expression of Brachyury (Bra) during development of Colostethus machalilla was analyzed with a polyclonal antibody. The observed molecular mass of Bra was of 48 kDa, as in Xenopus laevis. During cleavage, low levels of Bra were expressed. In contrast, in the blastula Bra became up-regulated, and Bra protein was present in a wide ring of surface cells. The surface expression of Bra disappeared in the gastrula, and a new ring of Bra-positive nuclei was detected in deep cells around the closing blastopore. The C. machalilla external and internal rings of Bra-positive nuclei apparently mark the prospective mesoderm in the blastula and gastrula, respectively. The two Bra expression rings were dissociated in time in the fairly slow developing embryos of this frog. Brachyury expression in the notochord became visible only after the blastopore closed, in contrast with X. laevis. In addition, Bra expression in the notochord indicated that dorsal convergence and extension occurred after blastopore closure. The C. machalilla Bra-positive notochord was originally exposed on the gastrocoel roof, in agreement with a superficial component of the prospective mesoderm.  相似文献   
18.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
19.
Lipomas are common benign tumours that can occur in most parts of the body. Lipomas arising from the deep temporal fat pad, found between the two layers of the deep temporal fascia, are rare, however; there has been only one documented case report to our knowledge. We describe a second case arising from the temporal fat pad in a patient treated at our unit, having previously reported the first one, and discuss the relevant anatomy and management.  相似文献   
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A healthy diet is essential to attain genetically determined peak bone mass and maintain optimal skeletal health across the adult lifespan. Despite the importance of nutrition for bone health, many of the nutritional requirements of the skeleton across the lifespan remain underexplored, poorly understood, or controversial. With increasingly aging populations, combined with rapidly changing diets and lifestyles globally, one anticipates large increases in the prevalence of osteoporosis and incidence of osteoporotic fractures. Robust, transparent, and reproducible nutrition research is a cornerstone for developing reliable public health recommendations to prevent osteoporosis and osteoporotic fractures. However, nutrition research is often criticized or ignored by healthcare professionals due to the overemphasis of weak science, conflicting, confusing or implausible findings, industry interests, common misconceptions, and strong opinions. Conversely, spurious research findings are often overemphasized or misconstrued by the media or prominent figures especially via social media, potentially leading to confusion and a lack of trust by the general public. Recently, reforms of the broader discipline of nutrition science have been suggested and promoted, leading to new tools and recommendations to attempt to address these issues. In this perspective, we provide a brief overview of what has been achieved in the field on nutrition and bone health, focusing on osteoporosis and osteoporotic fractures. We discuss what we view as some of the challenges, including inherent difficulties in assessing diet and its change, disentangling complex interactions between dietary components and between diet and other factors, selection of bone-related outcomes for nutrition studies, obtaining evidence with more unbiased designs, and perhaps most importantly, ensuring the trust of the public and healthcare professionals. This perspective also provides specific recommendations and highlights new developments and future opportunities for scientists studying nutrition and bone health. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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