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The studies were carried out to evaluate the constituents in the leaves ofCrataegus pinnatifida var.psilosa (Rosaceae) continuously. From the BuOH fraction of the MeOH extract, four flavonoid compounds, hyperoside (1), vitexin (2), 2"-O-rhamnosylvitexin (3) and quercetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside (4) were isolated and identified on the basis of their physico-chemical properties and spectroscopic evidences by comparison with authentic samples. 相似文献
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A 21-year-old woman with tuberous sclerosis presented with abdominal distension and flank pain. Imaging studies, including
CT and MR imaging, revealed bilateral renal mass lesions, containing fat and suggesting the diagnosis of tuberous sclerosis.
However the imaging characteristics of one of these lesions differed from the others with no radiologically detectable fat
tissue in this solid lesion suggesting renal cell carcinoma. Histopathological examination of this lesion in the left kidney
revealed an angiomyolipoma with minimal fat tissue. The radiological diagnosis of angiomyolipomas with minimal fat tissue
remains difficult and the differential diagnosis is discussed.
Received: 5 October 1998; Revised: 22 December 1998; Accepted: 7 June 1999 相似文献
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Min SH Hwang DY Kang TS Hwang JH Lim CH Lee SH Lim HJ Seo SJ Sheen YY Paik SG Cho JS Kim YK 《International journal of molecular medicine》2003,12(2):181-183
Apoptosis is an important process in the variety of different biological system including cell death and embryonic development. Inappropriate apoptosis is implicated in many human diseases such as Alzheimer's disease. Central component of the machinery of apoptosis program in neurons of patients with Alzheimer's disease includes proteins of caspases and Bcl-2 families. We examined whether endogenous protein levels of caspases and Bcl-2 families are expressed in a differential manner during the embryonic and postnatal development of BDF1 strain. Here, all four proteins with caspases-3, -9, Bcl-2 and Bax were highly expressed between embryonic day 19 and 1 week age of early postnatal development, but thereafter the expression dramatically declined. These patterns are needed to compare the proteins in the brains of APPsw-transgenic mice that are expected to be expressed highly in the brain of adult mice. Thus, the results are useful to understand fundamentally the mechanisms of the apoptotic changes during the embryonic and postnatal development of Alzheimer's model mice. 相似文献
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Identification of tumor suppressor loci on the long arm of chromosome 4 in primary small cell lung cancers 总被引:4,自引:0,他引:4
Recent cytogenetic studies have indicated that loss of the long arm of chromosome 4 is a frequent event in small cell lung cancer (SCLC), which suggests the presence of tumor suppressor genes there. To precisely map tumor-suppressor loci on chromosome 4q for further positional cloning efforts, we tested 15 primary SCLCs. Forty two polymorphic microsatellite markers located on chromosome 4q were used in the microsatellite analysis. We found that 12 (80%) of the 15 tumors exhibited loss of heterozygosity (LOH) in at least one of the tested microsatellite markers, and that 3 (25%) of these 12 tumors exhibited a larger area of deletion on chromosome 4q. Frequent LOH, defined as occurring in more than 50% of the tumors, was observed in five commonly deleted regions on 4q, namely 4q24, 4q27-28.3, 4q33, 4q34.1, and 4q34.3-35.2. Of these 5, LOH at 4q33 was the most frequent (61.5%). Six (40%) of the 15 tumors exhibited shifted bands in at least one of the tested microsatellite markers. Shifted bands occurred in 3.7% (23 of 630) of the loci tested. Our data demonstrated that at least five tumor-suppressor loci exist on the long arm of chromosome 4 and that they may play an important role in the development and progression of primary small cell lung cancer tumorigenesis. 相似文献
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