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51.
Hydatid disease is a parasitic infection generally occurring in specific geographical areas. Exclusive involvement of the muscles is extremely uncommon, because implantation at this site would require passage through the filters of the liver and lung. We describe a patient with a mass in the popliteal fossa of the knee for 7 years who was seen for pain and was found to have hydatid disease.  相似文献   
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Transmission of human herpesvirus 8 (HHV-8) may occur through various routes including breastfeeding and sexual intercourse. We attempted to detect HHV-8 infection in nine HIV-positive couples discordant for Kaposi's sarcoma who maintained a monogamous sexual relationship for at least one year. By quantitative real-time polymerase chain reaction and HHV-8 genotyping we provide strong evidence for the sexual transmission of HHV-8 in this unique cohort.  相似文献   
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Solitary fibrous tumours, which are commonly described as arising from the pleura, are rarely seen in the lower urinary tract. Although malignant changes have been reported, these tumours are usually benign. This case report discusses the radiological features, management strategy and histopathology of a solitary fibrous tumour arising from the prostate.  相似文献   
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Malignant melanoma is one of the most aggressive and invasive metastatic tumors derived from melanocytes that have undergone malignant transformation by acquisition of genetic and epigenetic alterations. Oligonucleotide microarray-based screening of distinct stages in the tumor progression model of cutaneous melanoma identified ASK/Dbf4, as a novel determinant for melanoma development. Quantitative real-time polymerase chain reaction-based confirmation of ASK/Dbf4 on a series of benign nevi, dysplastic nevi, primary cutaneous melanomas and cutaneous melanoma metastases; and a number of other controls using normal human melanocytes as calibrator not only revealed a melanoma-specific over-expression but also revealed that higher ASK/Dbf4-expressing melanomas were associated with lower relapse-free survival. Additionally, we also confirmed the observed over-expression of ASK/Dbf4 in melanoma using western blot analysis and immunohistochemistry. As ASK/Dbf4 is known to be a cyclin-like regulatory subunit of mammalian Cdc7 from the studies in yeast, the present study investigated its role in melanoma cells. In keeping with its expected role, our data suggest that up-regulated ASK/Dbf4 is localized in the nucleus and binds to human Cdc7 to form Cdc7-ASK/Dbf4 complexes in several analyzed melanoma cell lines. Further, we demonstrate that small interfering RNA-mediated depletion of ASK/Dbf4 retarded melanoma cell survival and proliferation. In summary, we report the differential regulation of a novel gene, namely ASK/Dbf4, in melanoma and suggest that up-regulation of ASK/Dbf4 is a novel molecular determinant with prognostic relevance that confers a proliferative advantage in cutaneous melanoma.  相似文献   
58.
Metalloproteases are responsible for the hemorrhagic effects of many snake venoms and contribute to other pathways that lead to local tissue damage. Methods that quantify snake venom metalloproteases (SVMP) are therefore valuable tools in research on the clinical, physiological, and biochemical effects of envenomation. Comparative analysis of individual, population, and species differences requires screening of large numbers of samples and treatments, and therefore require a method of quantifying SVMP activity that is simple, rapid, and sensitive. This paper demonstrates the properties of a new fluorometric assay of SVMP activity that can provide a measure of metalloprotease activity in 1 h. The assay is reliable, with variation among replicates sufficiently small to reliably detect differences in between species (F19,60 = 2924, p < 0.001), even for those venoms with low overall activity. It is also sensitive enough to detect differences among venoms using <2 ng of whole venom protein. We provide an example use of this assay to detect the presence of natural SVMP inhibitors in minute samples of blood plasma from rock squirrels (S. variegatus), a natural prey species for North American rattlesnakes. We propose this assay is a useful addition to the set of tools used to characterize venoms, as well as high-throughput screening of natural or synthetic inhibitors, or other novel therapeutic agents against SVMP effects.  相似文献   
59.
A retrospective analysis of the treatment of 70 patients with obstructed left colonic cancer was undertaken in order to assess whether staged or primary resection was more appropriate. Thirty-four patients had initial colostomy and staged resection (group 1) while 36 patients were treated by primary resection and immediate anastomosis following intra-operative bowel washout (group 2). There were seven deaths (10%), five in group 1 and two in group 2. The wound infection rate and average hospital stay were 44% and 36 days in group l and 19.4% and 16.5 days in group 2, respectively. Twenty per cent of patients in group 1 did not complete their staged procedures and had to live with their colostomies. The smoother postoperative recovery and shorter hospital stay was particularly significant in group 2 patients. As primary resection and anastomosis can now be performed with relative safety and reduced morbidity, we conclude that staged procedures can no longer be accepted as standard treatment for left colonic obstruction.  相似文献   
60.
Axillary lymph node enlargement can be the first and only manifestation of malignancy. Although lymphoma and metastasis from melanoma, breast and lung cancers are known causes, the primary tumour may remain undetected in some cases despite exhaustive investigations. Therefore, once the diagnosis of malignancy is confirmed by clinical examination followed by histology, further investigations should be limited to a search for treatable malignancies only. Extensive investigations with a hope of discovering the primary is useless and not cost effective. Close follow up may occasionally reveal new clinical signs when further investigations can be justified. This paper reports the clinical approach to diagnosis and management of such cases with examples of illustrative cases.  相似文献   
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