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111.
Comparison of Ashdown's medium, Burkholderia cepacia medium, and Burkholderia pseudomallei selective agar for clinical isolation of Burkholderia pseudomallei 下载免费PDF全文
Peacock SJ Chieng G Cheng AC Dance DA Amornchai P Wongsuvan G Teerawattanasook N Chierakul W Day NP Wuthiekanun V 《Journal of clinical microbiology》2005,43(10):5359-5361
Ashdown's medium, Burkholderia pseudomallei selective agar (BPSA), and a commercial Burkholderia cepacia medium were compared for their abilities to grow B. pseudomallei from 155 clinical specimens that proved positive for this organism. The sensitivity of each was equivalent; the selectivity of BPSA was lower than that of Ashdown's or B. cepacia medium. 相似文献
112.
The involvement of the pituitary in cases of toxoplasmosis has been described in the literature only rarely. This is the first report to describe pituitary adenoma in association with Toxoplasma gondii infection. The two patients were 43 and 19 year old women. Radiological examination revealed tumours in the sellar region. Microscopically, the tumours consisted of small homogeneous polygonal or round cells. Toxoplasma cysts were found among the tumour cells, a finding confirmed by Toxoplasma gondii specific antibody immunohistochemistry. The association between pituitary adenoma and toxoplasma raises the possibility that T gondii might be involved in the development of certain cases of pituitary adenoma. 相似文献
113.
Expression of L-Selectin (CD62L), CD44, and CD25 on activated bovine T cells 总被引:2,自引:0,他引:2 下载免费PDF全文
Waters WR Rahner TE Palmer MV Cheng D Nonnecke BJ Whipple DL 《Infection and immunity》2003,71(1):317-326
Mycobacterium bovis infection of cattle represents a natural host-pathogen interaction and, in addition to its economic and zoonotic impact, represents a model for human tuberculosis. Extravasation and trafficking of activated lymphocytes to inflammatory sites is modulated by differential expression of multiple surface adhesion molecules. However, effects of M. bovis infection on adhesion molecule expression have not been characterized. To determine these changes, peripheral blood mononuclear cells from M. bovis-infected cattle were stimulated with M. bovis purified protein derivative (PPD) or pokeweed mitogen (PWM) and evaluated concurrently for proliferation and activation marker expression. Stimulation with PPD or PWM increased CD25 and CD44 mean fluorescence intensity (MFI) and decreased CD62L MFI on CD4(+) cells from infected animals. CD62L MFI on PPD- and PWM-stimulated gammadelta T-cell receptor-positive (TCR(+)) and CD8(+) cells was also reduced compared to that of nonstimulated gammadelta TCR(+) and CD8(+) cells. Using a flow cytometry-based proliferation assay, it was determined that proliferating cells, regardless of lymphocyte subset, exhibited increased expression of CD25 and CD44 and decreased expression of CD62L compared to cells that had not proliferated. In contrast to proliferation, activation-induced apoptosis of CD4(+) cells resulted in a significant down regulation of CD44 expression. Lymphocytes obtained from lungs of M. bovis-infected cattle also had reduced expression of CD44 compared to lymphocytes from lungs of noninfected cattle. These alterations in surface molecule expression upon activation likely impact trafficking to sites of inflammation and the functional capacity of these cells within tuberculous granulomas. 相似文献
114.
Squamous-lined cysts of the pancreas: lymphoepithelial cysts, dermoid cysts (teratomas), and accessory-splenic epidermoid cysts 总被引:11,自引:0,他引:11
In the pancreas, 3 types of morphologically similar lesions may present as "squamous cysts": Lymphoepithelial cysts, dermoid cysts (monodermal teratomas), and epidermoid cysts in intrapancreatic accessory spleen. Lymphoepithelial cysts (LECs) are seen predominantly in men (M/F: 4/1) and in adulthood (mean age, 56, and range, 35 to 74 years). They may occur at any site of the organ (head, body, or tail). LECs are well-delineated cysts that may be multilocular (60%) or unilocular (40%), and they are characterized microscopically by stratified squamous epithelium surrounded by a band of mature lymphoid tissue with intervening well-formed germinal centers. Solid lymphoepithelial clusters are seldom seen. The pathogenesis of LECs is unclear; clinical diseases that are known to be associated with their counterparts in the salivary glands such as Sjogren disease or human immunodeficiency virus have not been documented for the LECs of the pancreas. The second type of squamous-lined cyst in the pancreas is the epidermoid cyst arising in intrapancreatic accessory spleen. These are located almost exclusively in the tail of the pancreas, in the fourth decade of life (mean age = 38). Their mean size is 4.5 cm (range, 2.3 to 6.5). In some cases, the cyst lining may be partly mucinous. Dermoid cysts of the pancreas are also rare. The cases that appear to be true dermoid cysts occur in a younger age group (mean age, 23, range, 2 to 53 years), and in contrast with LEC, there is no gender predominance. Mucinous epithelium, respiratory-type mucosa and sebaceous units are more readily identifiable in dermoid cysts, and they may contain hair. Subepithelial lymphoid tissue is not a feature. They are sometimes complicated by suppurative infections. The importance of these lesions is in their distinction from other cystic neoplasms, especially mucinous cystic tumors. 相似文献
115.
116.
大鼠肝抑素纯化及其生物活性的检测 总被引:3,自引:1,他引:3
用SephadecG-5凝胶过滤层析法,进一步纯化具肝抑素生物活性的大鼠肝蛋白质粗提品,以分离的大鼠再生肝的肝细胞为靶细胞,体外检测各洗脱峰浓缩物对肝细胞增殖的制率结果证明,E峰浓缩物的抑制作用最强,其活性比为粗提品的20倍,SDS聚丙烯酰胺电泳图及蛋白质迁移率测定表明,该浓缩物的主要成分为分子量13.5kD的多肽。本研究对大鼠肝抑素做了初步纯化,验证了该物质在肝再生中起重要调控作用的生物效应。 相似文献
117.
Naoki Utoguchi Tetsushi Nakata Hsien Hung Cheng Kenji Ikeda Hiroo Makimoto Yu Mu Shinsaku Nakagawa Motomasa Kobayashi Isao Kitagawa Tadanori Mayumi 《Inflammation》1997,21(2):223-233
Leukocyte adhesion to vascular endothelial cells is an essential step in the development of inflammatory diseases. We have searched for inhibitors of leukocyte-endothelial cell adhesion that could be used as anti-inflammatory drugs and found that bruceine B (0.2 g/ml; 0.44 M) inhibited human neutrophil or T cell adhesion to tumor necrosis factor- (TNF) stimulated human umbilical vein endothelial cells (HUVEC). The inhibition of neutrophil adhesion to TNF-stimulated HUVEC by bruceine B was not derived from cytotoxic effects, as determined by measurement of the level of lactate dehydrogenase (LDH) activity in conditioned medium. The effect of bruceine B on neutrophil adhesion to HUVEC was not seen when the neutrophils were preincubated with bruceine B. However, inhibitory effects were evident when the HUVEC were preincubated with bruceine B. Bruceine B also inhibited neutrophil adhesion to lipopolysaccharide-stimulated HUVEC and T cell adhesion to TNF-stimulated HUVEC. These findings suggest that bruceine B may have anti-inflammatory activity. 相似文献
118.
Interinstitutional variations of sensitometric curves of radiographic dosimetric films 总被引:1,自引:0,他引:1
Bos LJ Danciu C Cheng CW Brugmans MJ van der Horst A Minken A Mijnheer BJ 《Medical physics》2002,29(8):1772-1780
Depth and field size dependence of the sensitometric curves of radiographic films have been studied by various groups. Limited information is, however, available on the magnitude of the variations in sensitometric curves applied in clinical practice in different institutions. In this study we assessed in a systematic way the effect of the various parameters influencing the shape of the sensitometric curve: batch composition, irradiation conditions, film processing, and film scanning. Two types of film, Kodak X-Omat V and CEA TVS, were irradiated, processed, and analyzed in three different institutions. The interinstitutional variation of the sensitometric curves, expressed as the OD variation at 50 cGy, can be up to 32% and is mainly caused by differences in film processing and to a lesser degree to differences in batch composition, film scanning, and irradiation conditions. For the Kodak films, the average OD difference at 50 cGy between the three institutions is 17% as a result of differences in batch composition and 25% due to differences in processing conditions. For the CEA films these data are 6% and 24%, respectively. The long-term variation of the sensitometric curves of KODAK films in one institution was smaller than the differences in batch composition between the three institutions. The sensitometric curves of CEA films showed in one institution a large variation with time; the shape gradually varied from sigmoidal to quasilinear. By using relative OD values rather than absolute OD values, variations in sensitometric curves of KODAK films can be reduced to 2%. Consequently, one sensitometric curve is sufficient to derive relative dose values. If processing conditions are well controlled, it might therefore be advantageous to determine the absolute OD only at one or two dose values, in combination with a "universal" relative sensitometric curve. 相似文献
119.
Analysis of two IL-4 promoter polymorphisms in a cohort of atopic and asthmatic subjects 总被引:2,自引:0,他引:2
Hook S Cheng P Holloway J Riley G Sawyer G Le Gros G Beasley R 《Experimental and clinical immunogenetics》1999,16(1):33-35
The Th2 cytokine interleukin 4 (IL-4) has been identified as having a central role in driving the inflammatory immune responses which are present in atopic airway disease. This study examined the distribution of two putative IL-4 promoter polymorphisms (-285 C-T and -81 A-G) in groups of patients with severe and moderate asthma, non-asthmatic atopy and control subjects. Neither polymorphism was identified in any of the samples tested. The data suggest that either the polymorphisms are present at very low frequencies or are artefacts of the B cell lines from which they were identified. 相似文献
120.
Shyh Ren Chiang Hung Jen Tang Ping Chin Chang Kuo Chen Cheng Wen Chien Ko Chung Hua Chen Yin Ching Chuang 《Journal of microbiology, immunology, and infection》2007,40(2):123-133
BACKGROUND AND PURPOSE: Vibrio vulnificus causes primary bacteremia and necrotizing wound infection, leading to high morbidity and mortality in humans. This study aimed to evaluate the antimicrobial effect of cefotaxime and minocycline on proinflammatory cytokine levels in a murine model of V. vulnificus infection. METHODS: We investigated the dynamics of proinflammatory cytokines and their modulation by antimicrobial agents using a murine model of V. vulnificus infection. The change in cytokine levels was followed over a time course to identify the antimicrobial activity of the drugs against V. vulnificus. BALB/c female mice were challenged with an intraperitoneal infection using a clinical invasive isolate of Vv05191, and their cytokine levels were assayed over various time points. RESULTS: Serum levels of tumor necrosis factor-alpha, interleukin (IL)-1 beta, and IL-6 post-infection were found to be inoculum dose-dependent and positively correlated to the subsequent fatality rate in the infected mice. With an inoculum of 6.6 x 10(6) colony-forming units and intraperitoneal administration of cefotaxime, minocycline, or both, the serum and peritoneal fluid cytokine levels increased and then declined gradually. Comparison of the 3 antimicrobial regimens revealed that the magnitude of reduction in cytokine levels was greatest in mice treated with cefotaxime-minocycline combination. Moreover, the peritoneal fluid cytokine level in the combination group was significantly lower than that in the groups treated with minocycline or cefotaxime alone. CONCLUSIONS: The current results support the superiority of the combination therapy in treating invasive V. vulnificus infections. 相似文献