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991.
Malignant fibrous histiocytomas (MFH) as primary renal tumours are rare, with less than 50 cases described in the literature. We report a case of primary renal MFH of giant cell type in a 56-year-old man, who presented with bilateral dull flank pain, intermittent gross haematuria and body weight loss (6 kg in 3 months). Intravenous urography, computerized tomography (CT) and magnetic resonance image (MRI) showed right ureteral stones with mild hydronephrosis, and a solid mass at the lower pole of the left kidney associated with staghorn calculi, as well as tumour thrombi in the left renal vein and inferior vena cava. Left radical nephrectomy and evacuation of tumour thrombi from the left renal vein and inferior vena cava were performed. Histopathologic examination revealed malignant fibrous histiocytoma (MFH) of giant cell type. To the best of our knowledge, this is the first report of primary renal MFH associated with staghorn calculi. 相似文献
992.
Clinical Evaluation of Compression Ratios using JPEG2000 on Computed Radiography Chest Images 总被引:3,自引:1,他引:3
Min-Mo Sung Hee-Joung Kim Sun Kook Yoo Byoung-Wook Choi Ji-Eun Nam Hye-Sung Kim Jae-Hoon Lee Hyung-Sik Yoo 《Journal of digital imaging》2002,15(2):78-83
The efficient compression of radiographic images is of importance for improved storage and network utilization in support
of picture archiving and communication systems (PACS) applications. The DICOM Working Group 4 adopted JPEG2000 as an additional
compression standard in Supplement 61 over the existing JPEG. The wavelet-based JPEG2000 can achieve higher compression ratios
with less distortion than the Discrete Cosine Transform (DCT)-based JPEG algorithm. However, the degradation of JPEG2000-compressed
computed radiography (CR) chest images has not been tested comprehensively clinically. The authors evaluated the diagnostic
quality of JPEG2000-compressed CR chest images with compression ratios from 5:1 to 200:1. An ROC (receiver operating characteristic
analysis) and t test were performed to ascertain clinical performance using the JPEG2000-compressed images. The authors found
that compression ratios as high as 20:1 can be utilized without affecting lesion detectability. Significant differences between
the original and the compressed CR images were not recognized up to compression ratio of 50:1 within a confidence level of
99%. 相似文献
993.
After the gamma-irradiation sterilization, the most widely used orthopaedic grade polymer bearing liner material for the total joint replacement, ultra-high molecular weight polyethylene (UHMWPE), degrades through the progressive in vivo oxidation. The oxidative degradation makes UHMWPE brittle and leads to reduction of its mechanical properties. In this study, the effect of the in vivo post-irradiation ageing time on the wear of UHMWPE was investigated. Twelve retrieved polyethylene hip liners implanted for 3-16 years and then stored in the air for 1.5-8 years were used. Two types of the pin-on-disk wear testing were conducted. The uni-directional repeat pass rotating and the linear reciprocating wear testing were done with stainless steel disks against stationary polyethylene pins under 4MPa at 1Hz with bovine serum lubrication. Wear of the retrieved polyethylene hip liners does not have significant correlation with the in vivo or total ageing time. The linear reciprocal sliding motion generated a more pronounced wear than the uni-directional repeat pass sliding motion. This indicates that the kinematic motion significantly affects the wear of aged UHMWPE, having a brittle, white band region. 相似文献
994.
Cytokine responses in mice infected with<Emphasis Type="Italic"> Clonorchis sinensis</Emphasis> 总被引:5,自引:0,他引:5
FVB and BALB/c mice show different morbidity, development of Clonorchis sinensis, and pathological changes following C. sinensis infection. FVB mice are susceptible and BALB/c mice are relatively more resistant to C. sinensis infection. To investigate the relationship between cytokine reaction and susceptibility to C. sinensis infection in FVB and BALB/c mice, we described both the patterns and kinetics of Th1 cytokines and Th2 cytokines in spleen cell culture. Interleukin (IL)-4 and IL-10 cytokine production in the culture supernatants of the concanavalin-A-stimulated spleen cells increased at 2–3 weeks post-infection in both strains. IL-5 production increased between 2 and 5 weeks post-infection in both strains, and reached a peak level at 2 weeks post-infection in BALB/c mice and 4 weeks post-infection in FVB mice. In contrast, gamma interferon (IFN-) production decreased between 2 and 4 weeks in both strains. IL-2 production increased slightly in BALB/c mice following infection, but was unchanged in FVB mice. IL-4 production over preinfection levels was significantly higher in FVB mice, whereas IFN-, IL-2, and IL-10 production were significantly higher in BALB/c mice. The levels of serum immunoglobulin E (IgE) and blood eosinophils in both mouse strains significantly increased between 3 and 6 weeks postinfection. Serum IgE levels were significantly higher in FVB mice than in BALB/c mice. The results of this study suggest that susceptibility to C. sinensis infection is associated with Th2 cytokine production, especially IL-4 which is predominant in relatively susceptible FVB mice. 相似文献
995.
This study was designed to evaluate the effect of polyethylene oxide (PEO) and negatively charged side chains on blood compatibility. For this, novel copolymers (MMA/MPEOMA/VSA copolymers) with both PEO and negatively chargeable side chains were synthesized by random copolymerization of methyl methacrylate (MMA), methoxy PEO monomethacrylate (MPEOMA; PEO mol wt 1000), and vinyl sulfonic acid sodium salt (VSA) monomers of different compositions. MMA/MPEOMA copolymer (with PEO side chains) and MMA/VSA copolymer (with negatively chargeable side groups) also were synthesized for purposes of comparison. The synthesized copolymers were characterized by 1H-nuclear magnetic resonance spectroscopy and gel permeation chromatography. They were coated onto polyurethane (PU) or polymethyl methacrylate (PMMA) films by spin coating. The surface properties of MMA/MPEOMA/VSA copolymers were compared by water contact angle and zeta potential with those of MMA/MPEOMA and MMA/VSA copolymers of similar MPEOMA or VSA composition. Using electron spectroscopy for chemical analysis and scanning electron microscopy, respectively, the behaviors of the adsorption of blood proteins (albumin, gamma-globulin, fibrinogen, and plasma proteins) and the adhesion of platelets on the copolymer-coated surfaces also were compared. Among the copolymers, the MMA/MPEOMA/VSA copolymer with a monomer molar ratio 8:1:1 was observed to be particularly effective in preventing both protein adsorption and platelet adhesion on the surfaces, probably owing to the combined effects of highly mobile, hydrophilic PEO side chains and negatively charged side groups in aqueous solution. 相似文献
996.
Defective neurogenesis resulting from DNA ligase IV deficiency requires Atm 总被引:2,自引:0,他引:2 下载免费PDF全文
Ataxia telangiectasia results from mutations of ATM and is characterized by severe neurodegeneration and defective responses to DNA damage. Inactivation of certain DNA repair genes such as DNA ligase IV results in massive neuronal apoptosis and embryonic lethality in the mouse, indicating the occurrence of endogenously formed DNA double-strand breaks during nervous system development. Here we report that Atm is required for apoptosis in all areas of the DNA ligase IV-deficient developing nervous system. However, Atm deficiency failed to rescue deficits in immune differentiation in DNA ligase IV-null mice. These data indicate that ATM responds to endogenous DNA lesions and functions during development to eliminate neural cells that have incurred genomic damage. Therefore, ATM could be important for preventing accumulation of DNA-damaged cells in the nervous system that might eventually lead to the neurodegeneration observed in ataxia telangiectasia. 相似文献
997.
BACKGROUND: Forcipomyia taiwana is a tiny, blood-sucking midge that cause intense pruritis and swelling in sensitive individuals. It is distributed island-wide in rural Taiwan and Southern China. Objective: This study aimed to study the allergic immune responses and identify F. taiwana allergens. METHODS: Crude whole body F. taiwana extracts were prepared with phosphate-buffered saline. The specific IgE antibody was determined by enzyme-linked immunoassay and immunoblotting. Protein was analyzed by electrospray ionization tandem mass spectrometry. RESULTS: Among the 372 subjects that were exposed to F. taiwana bites, 179 (48%) reported an immediate skin reaction with/without delay reaction and 41(11.1%) reported a solely delay reaction. The skin of 21 subjects was tested with F. taiwana extract. Of these 21 subjects, 12 (57.1%) produced immediate skin reactions and contained high levels of specific IgE antibody against F. taiwana. Immunoblotting revealed that 11 allergenic components are able to bind specific IgE. Allergens of 22, 24, 35, 36, and 64 kDa bound 50, 50, 75, 66.7, and 75% of IgE-containing sera tested, respectively. Tryptic fragments of the 24, 35, 36, and 64 kDa allergens were analyzed by ESI-MS/MS. Selected tryptic peptides of 24, 35, and 36, and 64 kDa allergens exhibited significant sequence identity with triosephosphate isomerase of Anopheles merus,Tenebrio molitor,Ochlerotatus togoi, and Chrysops vittatus, fructose 1,6-bisphosphate aldolase of Antheraea yamamai and Homalodisca coagulata, and a slow muscle myosin S1 heavy chain of Homarusamericanus and a protein with unknown function from A. gambiae, respectively. The 35 and 36 kDa proteins may represent different isoforms of the fructose 1,6-bisphosphate aldolase. CONCLUSION: We conclude that immediate reaction to F. taiwana bites is IgE mediated and the 24 (For t 1), 35 (For t 2), and 64 kDa (For t 3) proteins are candidates for major F. taiwana allergens. Further studies are needed to confirm these allergens. 相似文献
998.
Antimicrobial agents played a miraculous role in the treatment of bacterial infections until resistant bacteria became widespread. Besides antimicrobial-resistant bacteria, many factors can influence the cure of infection. Nocardia infection may be a good example which is difficult to cure with antimicrobial agents alone. A 66-year-old man developed soft tissue infection of the right buttock and thigh. He was given prednisolone and azathioprine for pachymeningitis 3 months prior to admission. Despite surgical and antimicrobial treatment (sulfamethoxazole-trimethoprim), the infection spread to the femur and osteomyelitis developed. The case showed that treatment of bacterial infection is not always as successful as was once thought because recent isolates of bacteria are more often resistant to various antimicrobial agents, intracellular parasites are difficult to eliminate even with the active drug in vitro, and infections in some sites such as bone are refractory to treatment especially when the patient is in a compromised state. In conclusion, for the treatment of infections, clinicians need to rely on laboratory tests more than before and have to consider the influence of various host factors. 相似文献
999.
S. W. Choi W. S. Park J. M. Yang C. S. Kang H. S. Sun B. S. Kim E. J. Seo M. J. Lee C. S. Park 《Journal of Korean medical science》1994,9(4):299-303
Gene alterations of p53 tumor suppressor gene such as point mutations, deletions or insertions occur in various human cancers. p53 protein overexpression was studied immunohistochemically in 80 gastric adenocarcinomas using an anti-human p53 antibody (Pab 1801) and the avidin-biotin-peroxidase technique. We have also analyzed allele loss of the human p53 gene in 54 cases of gastric adenocarcinoma using polymerase chain reaction and restriction fragment length polymorphism. p53 immunostaining was also demonstrated in 48 of 80 carcinomas (60%). Normal mucosa was always negative. No relation could be found between p53 immunostaining and the degree of differentiation. 21 of the 54 patients(39%) were informative for the p53 exon 4. In ten of these informative cases(47.6%), tumor DNAs showed allele loss when compared with nonmetastatic lymph node DNAs. Seven of the ten(70%) showed p53 immunoreactivity. These findings suggest that mutations of the p53 gene may play a role in the development of gastric adenocarcinoma and that allele loss of p53 frequently occurs in p53 immunoreactive gastric adenocarcinoma. 相似文献
1000.
Altered expression of cell adhesion molecules in uninvolved gut in inflammatory bowel disease. 总被引:2,自引:0,他引:2
G M Schuermann A E Aber-Bishop P Facer J C Lee D S Rampton C J Dor J M Polak 《Clinical and experimental immunology》1993,94(2):341-347
Adhesion of circulating cells to vascular endothelium occurs in the early phase of inflammation, and is mediated by specific cell adhesion molecules. Many such adhesion molecules are increased in inflamed regions of ulcerative colitis (UC) and Crohn's disease (CD) but there is limited knowledge of their expression in the uninvolved gut, adjacent to inflammation. We investigated immunohistochemically the expression of platelet endothelial cell adhesion molecule-1 (PECAM-1), intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) on resected specimens taken at a distance of 2-4 cm from the inflamed area and without histological signs of inflammation. Compared with normal gut, we found (i) a significant increase of PECAM-1-positive vessels in the mucosa of uninvolved UC (149.0 +/- 24.1 vessels/mm2 (mean +/- s.d.); normal colon = 123.1 +/- 21.6; P = 0.004); (ii) a significant decrease of ICAM-1-positive vessels in uninvolved CD (111.9 +/- 22.6 vessels/mm2; normal ileum = 136.9 +/- 27.6; P = 0.04); and (iii) a moderate but statistically insignificant increase of LFA-1-positive cells in the mucosa of uninvolved UC and Crohn's ileitis. This altered expression of cell adhesion molecules may contribute to the early lesion in inflammatory bowel disease and provide new therapeutic opportunities. 相似文献