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121.
Different strains of Mycobacterium tuberculosis cause various spectrums of disease in the rabbit model of tuberculosis 下载免费PDF全文
Manabe YC Dannenberg AM Tyagi SK Hatem CL Yoder M Woolwine SC Zook BC Pitt ML Bishai WR 《Infection and immunity》2003,71(10):6004-6011
The rabbit model of tuberculosis has been used historically to differentiate between Mycobacterium tuberculosis and Mycobacterium bovis based on their relative virulence in this animal host. M. tuberculosis infection in market rabbits is cleared over time, whereas infection with M. bovis results in chronic, progressive, cavitary disease leading to death. Because of the innate resistance of commercial rabbits to M. tuberculosis, 320 to 1,890 log-phase, actively growing inhaled bacilli were required to form one grossly visible pulmonary tubercle at 5 weeks. The range of inhaled doses required to make one tubercle allows us to determine the relative pathogenicities of different strains. Fewer inhaled organisms of the M. tuberculosis Erdman strain were required than of M. tuberculosis H37Rv to produce a visible lesion at 5 weeks. Furthermore, with the Erdman strain, only 7 of 15 rabbits had healed lesions at 16 to 18 weeks; among the other animals, two had chronic, progressive cavitary disease, a phenotype usually seen only with M. bovis infection. Genotypic investigation of the Erdman strain with an H37Rv-based microarray identified gene differences in the RD6 region. Southern blot and PCR structural genetic analysis showed significant differences between M. tuberculosis strains in this region. Correlation of the relative pathogenicity, including disease severity, in the rabbit model with the strain genotype may help identify stage-specific M. tuberculosis genes important in human disease. 相似文献
122.
Abiodun O. Johnson Isaac A. Grillo Samuel A. Adebonojo 《Journal of the National Medical Association》1980,72(4):315-318
This report documents the first recorded patient in the recent literature with an esophageal perforation and an esophagopleural fistula following chest intubation for empyema. It was treated successfully by conservative method with feeding gastrostomy. It is important to realize that tube thoracostomy drainage is not an innocuous procedure and to be alert to this complication, especially in the presence of empyema. 相似文献
123.
Claire M. Payne Raymond B. Nagle Samuel H. Paplanus Anna R. Graham Martin M. Berman 《Ultrastructural pathology》1986,10(6):539-552
Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature. 相似文献
124.
Measurement of mesothelioma on thoracic CT scans: a comparison of manual and computer-assisted techniques 总被引:4,自引:0,他引:4
Armato SG Oxnard GR MacMahon H Vogelzang NJ Kindler HL Kocherginsky M Starkey A 《Medical physics》2004,31(5):1105-1115
Our purpose in this study was to evaluate the variability of manual mesothelioma tumor thickness measurements in computed tomography (CT) scans and to assess the relative performance of six computerized measurement algorithms. The CT scans of 22 patients with malignant pleural mesothelioma were collected. In each scan, an initial observer identified up to three sites in each of three CT sections at which tumor thickness measurements were to be made. At each site, five observers manually measured tumor thickness through a computer interface. Three observers repeated these measurements during three separate sessions. Inter- and intra-observer variability in the manual measurement of tumor thickness was assessed. Six automated measurement algorithms were developed based on the geometric relationship between a specified measurement site and the automatically extracted lung regions. Computer-generated measurements were compared with manual measurements. The tumor thickness measurements of different observers were highly correlated (r > or = 0.99); however, the 95% limits of agreement for relative inter-observer difference spanned a range of 30%. Tumor thickness measurements generated by the computer algorithms also correlated highly with the average of observer measurements (r > or = 0.93). We have developed computerized techniques for the measurement of mesothelioma tumor thickness in CT scans. These techniques achieved varying levels of agreement with measurements made by human observers. 相似文献
125.
A two year (1992 to 1993) in vivo assessment of Plasmodium falciparum sensitivity to chloroquine was conducted in two communities at Dodowa (hyperendemic) and Prampram (mesoendemic) in Southern Ghana. A slightly modified World Helath Organization standard field test (7 day test) for response of Plasmodium falciparum asexual parasites to chloroquine was used for the survey. In 1992, 16.2% (12/74) responses were classified as exhibiting chloroquine resistance at RI (14.8% ) and RII (1.4%) in the dry season and 8.2% (10/122) responses at RI in the wet season in the hyperendemic community. Only a single response (1/144; 0.7%) at RI showed resistance in the mesoendemic community. The rest of the responses in both communities were classified as sensitive to chloroquine. In the hyperendemic community, 8.4% (13/154) of responses in the dry season showed resistance at RI and 1.3% (82/150) at RI (0.7%) and RII (0.7%) in the wet season in 1993. In the mesoendemic community 1 (1.0%) response was resistant at RI in the wet season. The rest of the responses were classified as sensitive responses to chloroquine. No RIII response was encountered in any of the communities. The pattern of RI and RII responses did not show any seasonal variations in the mesoendemic community. However, they were generally higher in the dry season than in the wet season in the hyperendemic community. 相似文献
126.
127.
Mohamed Guled Samuel Myllykangas Henry F Frierson Stacey E Mills Sakari Knuutila Edward B Stelow 《Modern pathology》2008,21(6):770-778
Olfactory neuroblastoma is an unusual neuroectodermal malignancy, which is thought to arise at the olfactory membrane of the sinonasal tract. Due to its rarity, little is understood regarding its molecular and cytogenetic abnormalities. The aim of the current study is to identify specific DNA copy number changes in olfactory neuroblastoma. Thirteen dissected tissue samples were analyzed using array comparative genomic hybridization. Our results show that gene copy number profiles of olfactory neuroblastoma samples are complex. The most frequent changes included gains at 7q11.22-q21.11, 9p13.3, 13q, 20p/q, and Xp/q, and losses at 2q31.1, 2q33.3, 2q37.1, 6q16.3, 6q21.33, 6q22.1, 22q11.23, 22q12.1, and Xp/q. Gains were more frequent than losses, and high-stage tumors showed more alterations than low-stage olfactory neuroblastoma. Frequent changes in high-stage tumors were gains at 13q14.2-q14.3, 13q31.1, and 20q11.21-q11.23, and loss of Xp21.1 (in 66% of cases). Gains at 5q35, 13q, and 20q, and losses at 2q31.1, 2q33.3, and 6q16-q22, were present in 50% of cases. The identified regions of gene copy number change have been implicated in a variety of tumors, especially carcinomas. In addition, our results indicate that gains in 20q and 13q may be important in the progression of this cancer, and that these regions possibly harbor genes with functional relevance in olfactory neuroblastoma. 相似文献
128.
Matthew J. Bassignani Samuel J. Dwyer III Jonathan M. Ciambotti Juan M Olazagasti Ruth Moran Sean Moynihan Alfred C. Weaver Andrew M. Snyder 《Journal of digital imaging》2004,17(1):18-27
Teleradiology allows contemporaneous interpretation of imaging exams performed at some distance from the interpreting radiologist. The transmitted images are usually static. However, there is benefit to real-time review of full-motion ultrasound (US) exams as they are performed. Telesonography is transmission of full-motion sonographic data to a remote site. We hypothesize that US exams, read after having been compressed utilizing Motion Picture Experts Group version 4 (MPEG-4) compression scheme, transmitted over the Internet as streaming multimedia, decompressed, and displayed, are equivalent in diagnostic accuracy to reading the examinations locally. MPEG-4 uses variable compression on each image frame to achieve a constant output bit rate. With less compression, the bit rate rises, and the only way the encoder can contain bit rate within the set bandwidth is by lowering frame rate or reducing image quality. We review the relevant technologies and industry standard components that will enable low-cost telesonography. 相似文献
129.
Horie H Yoshida H Matsuura K Miyazawa M Wakabayashi K Nomoto A Hashizume S 《Journal of medical virology》2002,68(3):445-451
Type 1, 2, and 3 vaccine-derived polioviruses were isolated from a sewage disposal plant located downstream of the Oyabe River in Toyama Prefecture, Japan, between October 1993 and September 1995. Neurovirulence was analyzed in 13 type 1 vaccine-derived strains, using mutant analysis by polymerase chain reaction and restriction enzyme cleavage (MAPREC). Nine strains (69%) were estimated to have marked neurovirulence. Some of the neutralizing antigenic sites, temperature sensitivity, and plaque-forming ability of two virulent vaccine-derived poliovirus strains were similar to Mahoney strain. The neutralizing activity of human sera obtained after oral poliomyelitis vaccine (OPV) administration against one of the virulent vaccine-derived polioviruses was examined. Although all human sera showed sufficient neutralizing activity for the prevention of poliomyelitis by vaccine-derived poliovirus strains, a lower titer than that against Sabin type 1 strain was observed. Vaccination against virulent vaccine-derived poliovirus will be effective. However, the environmental presence of viruses that have properties similar to those Mahoney strain is a threat. The introduction of inactivated poliovirus vaccine (IPV), and well-maintained herd immunity, together with reinforced environmental surveillance is important for the final phase of the polio eradication program by the World Health Organization (WHO). 相似文献
130.
苏肖好 《国际中华应用心理学杂志》2006,3(3):200-209
目的 探讨香港与澳门两地中小学学校辅导的发展,就辅导工作的内容、开展情况、辅导人员在建设上的差别以及发展速度相异的原因等方面作分析。方法 本研究以香港及澳门中小学的学校辅导员/社工为调查对象,利用自编问卷方式进行调查.结果 (1)两地的辅导员都一致认为,通过学校辅导服务可以帮助中学生建立良好的社交行为及人际关系,(2)两地的中小学都在帮助学生更好地接纳他人及尊重他人这个项目上都做得较好;(3)两地的中小学校辅导的目标不再是以处理学生的偏差行为为主,转而注重学生的个人潜能发展;(4)就课堂辅导活动开展的情况来看,香港在班级辅导、全年级辅导及全校性辅导方面都做得比较好,而澳门的全校性辅导通有待加强。至于课堂以外的辅导活动,两地均以个别晤谈,团体辅导、心理卫生讲座以及工作坊等方式开展辅导活动为多。(5)在持介制度上,香港中小学都做得比较完善;(6)咨询服务方面,香港小学做得较多,而澳门则是中学做得较多;(7)新生适应服务方面,香港较澳门做得较多;(8)香港的学校比澳门学校更多地与其它机构共同合辩小区教育;(9)香港及澳门的中学辅导员主要是学校自聘/校内编制,两地的中学社工主要是由政府资助民间志愿机构派驻。香港的小学导员以学校自聘/校内编制和政府派驻为主,香港的小学社工以政府直接派驻为多;澳门的小学辅导员为政府派驻,小学社工则由政府资助民间志愿机构派驻为多。(10)对于两地学校辅导人员学历的比较,香港中学及小学专职辅导贝、专职社工的学历均较澳门为高.结论 两地在学校辅导目标上比较一致;两地均建立了发展辅导为主,预防辅导及治疗辅导并重的辅导模式;家庭问题及人际关系问题为两地中小学生的困扰问题;两地的学校辅导活动呈现一个多元化的局面,但香港较澳门丰富;澳门需要建立完善的转介机构。 相似文献