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1.
Primary tumours of the heart are uncommon and, among them, hemangioendotheliomas are exceptionally rare. The purpose of this paper is to present a rare case of right ventricular hemangioendothelioma treated surgically with success.  相似文献   
2.
Summary The authors describe three cases of systemic lupus erythematosus (SLE) associated with Kikuchi's histiocitic necrotizing lymphadenitis (HNL). Two patients presented a cytomegalovirus infection concomitantly with Kikuchi's lymphadenitis; in one of them the onsets of SLE and HNL were simultaneous. In the third case an inguinal HNL was concomitant with vaginitis of unknown aetiology.  相似文献   
3.
We have identified a novel missense transition (362G→A) in exon 3 of the COL4A5 gene in a male patient with late-onset Alport syndrome. We used non-isotopic single strand conformation polymorphism, heteroduplex analysis, and automated DNA sequencing. The mutation changes a conserved glycine at codon 54 for an aspartic acid (Gly54Asp), which abolishes a BstNI site. Using restriction analysis, we identified the heterozygous carrier status in the two daughters of the proband. Our findings are in keeping with the hypothesis that slower progressive forms of Alport syndrome are more often associated with missense mutations rather than large deletions or frameshifts. This is the first mutation described in the N-terminus triple helical 7S domain of the COL4A5 gene in an Alport syndrome patient.  相似文献   
4.
We observed that peripheral T cells activated in vivo or invitro by superantigens are susceptible to cell death when theirantigen receptor is cross-linked with the appropriate anti-ßTCR mAb. TCR ligation by mAbs specifically drove the T cellclonal deletion in both CD4+ and CD8+ cell subsets. An IL-2/1L-2Rinteraction seems to be a critical step In predisposing superantigenactivated cells to death; In fact, in vivo IL-2R bockade reversedT cell deletion In superantlgen plus anti-ß TCR mAbtreated mice. TCR ligatlon by mAbs also produced cell deathof the relevant targets in in vitro IL-2 activated T cells.Surprisingly, no T cell deletion was demonstrable in IL-2 activatedcells following staphylococcal enterotoxin B - TCR Interaction,ruling out the possibility that superantigen in Itself can inducecell death. Thus, while superantigen activation opens the celldeath program, a subsequent TCR-antigen (self) Interaction appearsnecessary to produce clonal deletion in mature T lymphocytes.  相似文献   
5.
Phenylalanine hydroxylation across the kidney in humans. BACKGROUND: Although phenylalanine hydroxylase activity is detectable in in vitro renal tissue preparations, no data on in vivo phenylalanine hydroxylation across the human kidney, as well as on its possible contribution to whole-body hydroxylation, currently exist. METHODS: To this aim, we have measured whole-body, renal, and splanchnic phenylalanine hydroxylation to tyrosine, as well as phenylalanine and tyrosine rates of appearance (Ra) and disposal (Rd), in postabsorptive subjects by means of renal and splanchnic arteriovenous catheterization combined with phenylalanine and tyrosine isotope infusions. RESULTS: In the kidney, a relevant phenylalanine hydroxylation activity was detected (3.51 +/- 0.97 micromol/min x 1.73 m2 of body surface), whereas it was 2.48 +/- 1. 35 micromol/min x 1.73 m2 across the splanchnic area. These two sites together accounted for virtually the entire whole-body phenylalanine hydroxylation. Renal production of tyrosine from phenylalanine hydroxylation accounted for approximately 13% of whole-body tyrosine Ra, whereas renal total tyrosine Ra accounted for approximately 34% of whole-body tyrosine Ra. In the splanchnic area, these figures were approximately 9 and 40%, respectively. Hydroxylation accounted for approximately 70% of phenylalanine Rd in the kidney, as opposed to approximately 8% in the splanchnic area. CONCLUSIONS: These data indicate that hydroxylation represents the major route of phenylalanine disposal within the kidney. The kidney and the splanchnic bed together account for all of the whole-body phenylalanine hydroxylation. These data also provide a further explanation for the reduced tyrosine pools occurring in uremia.  相似文献   
6.
欧洲血管外科学会召集颈动脉疾病领域的专家制定了关于颈动脉疾病有创性治疗的最新指南.根据证据级别对推荐意见进行分级.对于狭窄程度50%的有症状患者,如果围手术期卒中/死亡发生率<6%,则推荐行颈动脉内膜切除术(carotid endarterctomy,CEA)(A级推荐),最好在患者最近发作的2周内进行(A级推荐).对于狭窄程度为70%~99%并且年龄在75岁以下的男性无症状患者,如果围手术期卒中/死亡发生率<3%,也推荐行CEA(A级推荐).女性无症状患者从CEA中获得的益处明显不如男性患者(A级推荐).因此,只有年龄较小的合适的女性患者才考虑行CEA(A级推荐).颈动脉补片血管成形术优于直接缝合(A级推荐).在CEA术前、术中和术后均应给予阿司匹林(75~325 mg/d)和他汀类药物治疗(A级推荐).颈动脉支架置入术(carotid arterystenting,CAS)仅适用于CEA高危患者,并且应在围手术期卒中/死亡发生率较低的大型中心或是在随机对照试验中进行(C级推荐).在CAS治疗的同时,应使用阿司匹林+氯吡格雷双重抗血小板治疗(A级推荐).使用颈动脉保护装置可能有益(C级推荐).  相似文献   
7.
Cardiac hydatid disease represents 0.02-2% of the possible locations of the parasite. In these last few years we have seen an increase in the percentage of cardiac hydatid disease treated with surgery. The Authors report on two patients who underwent surgery for the excision of cardiac hydatid cysts. The Authors agree that in spite of the rarity of cardiac hydatid disease it should be investigated routinely by two-dimensional echocardiography in the presence of hepatic or pulmonary hydatid disease in order to prevent the possible spread of the parasite throughout the body.  相似文献   
8.
Capillaria hepatica is a zoonotic parasite (nematode) found in the liver of many mammals, especially rodents, worldwide. In this study, 94 non-commensal rodents were trapped in a forest area near Dijon, France, including 65 Apodemus spp. and 29 Myodes glareolus. Pathology was studied on the liver of each rodent. Histological lesions consisting of chronic multifocal granulomatous hepatitis due to both eggs and adult forms of the parasite were observed in the liver of eight M. glareolus and one Apodemus spp. The global prevalence of 9.6 % was significantly higher in M. glareolus (27.6 %) compared to Apodemus spp. (1.5 %) living in the same ecosystem. No significant difference in the infection rate was found between males and females of M. glareolus. Gross pathological lesions compatible with capillariasis were observed in four of nine rodents. These results raise the role of wild rodents in the maintenance of capillariasis in nature, and their possible role in the transmission to humans.  相似文献   
9.
This article describes a technique for surgically extruding severely compromised roots needing prosthetic rehabilitation. Unlike previously described approaches, the technique does not require advanced clinical skills or equipment, may reduce the risk of tooth or bone fracture during the luxation maneuvers, and does not seem to interfere with the alveolar socket healing process.  相似文献   
10.
BACKGROUND: During neoplastic progression, alterations in transforming growth factor beta1 (TGF-beta1) dependent control of cell growth may be an important mechanism of selective proliferation of transformed cellular clones. Defective regulation of TGF-beta1 receptors has been reported to occur in a number of human malignant tumours while little is known of the actual levels of this growth inhibitory cytokine in cancer. On the basis of the demonstrated ability of major lipid peroxidation products such as 4-hydroxynonenal to modulate TGF-beta1 expression and synthesis, we speculated that decreased lipid oxidation, as frequently observed in neoplastic tissues, would contribute to the selective promotion of tumour growth through decreased expression of the cytokine within the tumour mass. AIMS: To seek a possible association between steady state levels of major aldehydic end products of lipid peroxidation and TGF-beta1 content in human colon cancer at different stages of growth. PATIENTS AND METHODS: Tissue biopsies from 15 adult patients with colon adenocarcinoma of different TNM and G stagings were compared with regard to lipid peroxidation aldehydes and net TGF-beta1 levels. For a more comprehensive analysis, cytokine type I and II receptors were measured in tumour biopsies. In one set of experiments, to support the conclusions, the apoptotic effect of TGF-beta1 was evaluated in a human colon cancer cell line, CaCo-2, retaining receptor changes consistent with those observed in cancer patients. RESULTS: With the exception of two extremely advanced cases (T4/G3) in which tissue levels of lipid peroxidation were within the normal range, 4-hydroxynonenal was significantly decreased in all other cancer specimens. Consistent with lipid peroxidation levels, TGF-beta1 protein was markedly decreased or even negligible compared with the corresponding normal tissue surrounding the tumour in all tested biopsies except for the two T4/G3 colon cancers in which cytokine content was again within the normal range. As regards TGF-beta1 receptors, both in tumour sections and CaCo-2 cells, downregulation was greater for TGF-beta1 receptor I than for receptor II. Of note, in CaCo-2 cells, incubation with appropriate doses of TGF-beta1 led to marked nuclear fragmentation and apoptosis. CONCLUSIONS: Evasion of human colon cancer cells from TGF-beta1 mediated growth inhibition appears to be due not only to downregulation of TGF-beta1 receptors, which is inconsistent and unrelated to cancer development, but also to the constant low concentration of this cytokine in the tumour mass. The associated levels of lipid peroxidation aldehydes, much lower than in control tissue, probably represent a lower stimulus for TGF-beta1 production in the neoplastic area and thus a favourable condition for neoplastic progression.  相似文献   
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