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91.
Julian C Chantrey Andrew M Borman Elizabeth M Johnson Anja Kipar 《Medical mycology》2006,44(4):375-378
Emmonsia crescens, a dimorphic fungus of the order Onygenales, is primarily a pathogen of lower animals and rarely humans. Inhaled conidia of E. crescens fail to germinate in the lungs, and instead simply enlarge in lung tissue to become giant adiaspores. We present here the case of fatal Emmonsia crescens infection in a wild-caught British water vole (Arvicola terrestris). Histopathological examination of the animal, which died in captivity, revealed a multifocally extensive granulomatous reaction containing oval adiaspores scattered irregularly throughout the lungs. Mycological examination of fungus cultured from lung tissue and PCR amplification and sequencing of rDNA gene fragments of the cultured organism confirmed the diagnosis of massive infection by E. crescens. 相似文献
92.
The effect of increased sodium in the drinking water on right ventricular hypertrophy, right ventricular failure and ascites in broiler chickens 总被引:5,自引:0,他引:5
R J Julian 《Avian pathology》1987,16(1):61-71
One hundred commercial male broiler chickens were grown to 27 days in four floor pens on a commercial diet containing 0.14% sodium (Na+). From day 6 each pen received different levels of sodium chloride (NaCl) in the drinking water; 0.0%, 0.15% (0.06% Na+), 0.3% (0.12% Na+) and 0.6% (0.24% Na+). Eight chicks from each group were killed at 13, 20 and 27 days and examined for right ventricular hypertrophy (RVH) and right ventricular failure (RVF). By day 27 as little as 0.06% added Na+ caused two cases of RVH and one case of RVF with ascites, typical of the ascites caused by RVF in commercial broilers. RVH, RVF and ascites developed earlier in broilers on higher levels of Na+. 相似文献
93.
Paul Kruszka Tommy Hu Sungkook Hong Rebecca Signer Benjamin Cogné Betrand Isidor Sarah E. Mazzola Jacques C. Giltay Koen L. I. van Gassen Eleina M. England Lynn Pais Charlotte W. Ockeloen Pedro A. Sanchez‐Lara Esther Kinning Darius J. Adams Kayla Treat Wilfredo Torres‐Martinez Maria F. Bedeschi Maria Iascone Stephanie Blaney Oliver Bell Tiong Y. Tan Marie‐Ange Delrue Julie Jurgens Brenda J. Barry Elizabeth C. Engle Sarah K. Savage Nicole Fleischer Julian A. Martinez‐Agosto Kym Boycott Elaine H. Zackai Maximilian Muenke 《American journal of medical genetics. Part A》2019,179(10):2075-2082
Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features. 相似文献
94.
Summary Autoregressive topographic EEG analysis was used to determine topographic EEGs of the total power in quiet and active sleep stages in 33 healthy premature infants of 34 to 40 weeks conceptional age. The developmental characteristics were also examined by simultaneously referring to the autoregressive pattern discrimination of topographic EEGs between different conceptional age groups in both sleep stages. Treating 10.24 seconds of EEG as one segment, the topographic EEG of 10 segments in each of the quiet and active sleep stages as well as their mean were obtained. In both sleep stages the results showed a small peak in total power in the frontal region and a large peak in the occipital region, but total power was greater in the quiet sleep. Total power decreased with increasing conceptional age. Topographic pattern discrimination between different conceptional age groups showed significant differences mainly in the frontal, temporal and occipital regions. It was concluded that regional differences in the development of EEG in premature infants could be clarified by means of topographic EEG analysis and the pattern discrimination method using the autoregressive model.This study was supported by a Scientific Research Grant (No. 02670450) from the Japanese Ministry of Education. 相似文献
95.
Utility of a multiplex PCR assay for detecting herpesvirus DNA in clinical samples 总被引:4,自引:0,他引:4 下载免费PDF全文
Druce J Catton M Chibo D Minerds K Tyssen D Kostecki R Maskill B Leong-Shaw W Gerrard M Birch C 《Journal of clinical microbiology》2002,40(5):1728-1732
A multiplex PCR was designed to amplify herpes simplex virus types 1 and 2, cytomegalovirus, and varicella-zoster virus DNA present in a diverse range of clinical material. The susceptibility of these viruses to in vivo inhibition by at least one antiviral drug was an important consideration in their inclusion in the multiplex detection system. An aliquot of equine herpesvirus was introduced into each specimen prior to extraction and served as an indicator of potential inhibitors of the PCR and a detector of suboptimal PCR conditions. Compared to virus isolation and immunofluorescence-based antigen detection, the multiplex assay yielded higher detection rates for all viruses represented in the assay. The turnaround time for performance of the assay was markedly reduced compared to those for the other techniques used to identify these viruses. More than 21,000 tests have been performed using the assay. Overall, the multiplex PCR enabled the detection of substantially increased numbers of herpesviruses, in some cases in specimens or anatomical sites where previously they were rarely if ever identified using traditional detection methods. 相似文献
96.
97.
为了探讨一种适合培养细胞的低本底、低成本免疫细胞化学方法 ,本研究将低浓度的 Triton X-10 0加入抗体稀释液和洗液中 ,观察了其对 ABC反应时的抗体和 ABC的使用浓度和反应效果的影响。结果证明 ,在抗体稀释液和洗液中加入 0 .1%Triton X-10 0可以增强细胞对抗体的通透性 ,在不减弱阳性信号的状况下使 -抗的使用浓度明显降低 ,使生物素化二抗和 ABC的使用浓度达到 1/ 10 0 0~ 1/ 40 0 0 ,并大大减弱染色本底。本研究结果提示 ,在这一稀释度明显低于目前试剂盒建议的使用浓度。在充分显示阳性信号的前提下 ,使抗体的使用浓度和量大幅度减少 ,从而实现了降低本底和实验成本的目的 相似文献
98.
Outbreak of serogroup C meningococcal disease caused by a variant of Neisseria meningitidis serotype 2a ET-15 in a community of men who have sex with men 下载免费PDF全文
Tsang RS Kiefer L Law DK Stoltz J Shahin R Brown S Jamieson F 《Journal of clinical microbiology》2003,41(9):4411-4414
We describe an outbreak, in a community of men who have sex with men, of serogroup C meningococcal disease caused by a genetic variant of the serotype 2a ET-15 Neisseria meningitidis characterized by a point mutation in the gene coding for the serotype 2a antigen. A microbiological characterization of the outbreak strain is presented in this report. 相似文献
99.
Protection against infection with Neisseria meningitidis group B serotype 2b by passive immunization with serotype-specific monoclonal antibody 总被引:4,自引:8,他引:4
Hybridomas derived from mice immunized with Neisseria meningitidis serogroup B serotype 2b (B,2b) outer membrane preparations produced monoclonal antibodies (MAbs) specific for major outer membrane proteins of classes 1, 2, and 5. The MAbs were examined by enzyme-linked immunosorbent assay against a selected panel of seven strains of N. meningitidis (B,2b) of different sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns, a serotype 2a, and a nontypable strain. The five MAbs selected were all bactericidal and of different immunoglobulin subclasses. None of the MAbs reacted with other bacterial strains in a dot-enzyme immunoassay. The corresponding antigenic determinant for each MAb was localized on a specific outer membrane protein by immunoblotting of sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of major outer membrane proteins. MAbs M5-11 and M5-30 bound to the class 2 protein and were serotype 2b specific. MAb M2-20 bound to the class 1 protein, and MAbs M5-16 and M5-19 bound to the class 5 protein. A mouse model of infection was established whereby a local infection progressed to lethal bacteremia over 3 days, and 50% of the animals were killed with an intraperitoneal injection of 10 meningococci plus 4% mucin and 1.6% hemoglobin. The ability of the MAbs to provide passive protection against experimental infection with N. meningitidis (B,2b) was examined. Both serotype-specific MAbs M5-11 and M5-30 were highly protective even though they were of different immunoglobulin subclasses. The class 5-specific MAb offered no protection, while the class 1-specific MAb gave limited protection. It may therefore be possible to provide protection against serotype 2b infection by using as vaccine the class 2 serotype-specific surface-exposed outer membrane protein epitopes defined by MAb M5-11 or M5-30. 相似文献
100.
The variation in isometric tension with sarcomere length in vertebrate muscle fibres 总被引:65,自引:20,他引:65
1. The variation of isometric tetanus tension with sarcomere length in single fibres from frog striated muscle has been re-investigated with special precautions to ensure uniformity of sarcomere length within the part of the fibre being studied.2. In most respects the results of Ramsey & Street (1940) were confirmed, but (a) the peak of the curve was found to consist of a plateau between sarcomere lengths of 2.05 and 2.2 mu, (b) the decline of tension above this plateau is steeper than found by Ramsey & Street, and (c) the decline of tension below the plateau becomes suddenly steeper at a sarcomere length of about 1.67 mu.3. Many features of this length-tension relation are simply explained on the sliding-filament theory.4. It is concluded that, in the plateau and at greater lengths, the tension on each thin filament is made up of equal contributions from each bridge which it overlaps on adjacent thick filaments.5. Internal resistance to shortening is negligible in this range but becomes progressively more important with shortening below the plateau. 相似文献