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81.
Curvularia infections in humans are relatively uncommon despite the ubiquitous presence of this soil-dwelling dematiaceous fungus in the environment. Originally thought to be solely a pathogen of plants, Curvularia has been described as a pathogen of humans and animals in the last half-century, causing respiratory tract, cutaneous, and corneal infections. Only three previous cases of central nervous system involvement by Curvularia have been documented in the medical literature. We report a fatal case of cerebral Curvularia infection in which there was no known history of immunocompromise or prior respiratory tract or sinus infection in the patient.  相似文献   
82.
A family study of hydrocephalus resulting from aqueduct stenosis.   总被引:3,自引:1,他引:3       下载免费PDF全文
Stenosis of the aqueduct of Sylvius accounts for about one third of cases of congenital hydrocephalus. At least 32 families have been reported in which the aqueduct stenosis is inherited in an X linked fashion. In half of these families, flexed adducted thumbs were noted in some affected family members. Occasionally other male members were mentally retarded, suggesting limited expression of the gene. The problem of giving genetic advice to an isolated, clinically unremarkable, case of aqueduct stenosis remains, so a family study was undertaken based on 24 such cases seen at The Hospital for Sick Children over a 19-year period. There were 15 male and nine female index patients. The diagnosis was confirmed in all cases by air encephalogram. One boy had a radial club hand and another developed clasped thumbs secondary to spasticity. No cases had hyaloidoretinal dysplasia. The 15 boys had 18 brothers and 19 sisters, of whom one sister was similarly affected. The nine girls had 12 sibs, none of whom was affected. This study, combined with a similar study in the USA, suggests that the empirical risk of recurrence of a sporadic case of aqueduct stenosis is about 4.5%.  相似文献   
83.
A new route for the synthesis of high glass transition temperature, thermally stable polymer foams has been developed, using compositionally asymmetric microphase-separated block copolymers where the minor component (poly(propylene oxide)) is thermally labile and the major component (polyimide) is thermally stable. The minor component decomposes to low molecular weight species upon heating, and the decomposition products diffuse out of the film, leaving behind pores embedded in a matrix of the thermally stable component. In this study, the polyimide block was crosslinked with ethynyl functionalities to obtain a stable porous structure. The decomposition of the propylene oxide in the block copolymer was studied by thermogravimetric, dynamic mechanical and thermomechanical analyses. Mild conditions were required to avoid rapid depolymerization of the propylene oxide and plasticization of the polyimide matrix. The foams showed pore sizes with diameters up to a micrometer in size as well as the expected reduction in the mass density.  相似文献   
84.
The p44 gene of the agent of human granulocytic ehrlichiosis (aoHGE) encodes a 44-kDa major outer surface protein. A technique was developed for the typing of the aoHGE based on the PCR amplification of the p44 gene followed by a multiple restriction digest with HindIII, EcoRV, and AspI to generate restriction fragment length polymorphism patterns. Twenty-four samples of the aoHGE were collected from geographically dispersed sites in the United States and included isolates from humans, equines, canines, small mammals, and ticks. Six granulocytic ehrlichiosis (GE) types were identified. The GE typing method is relatively simple to perform, is reproducible, and is able to differentiate among the various isolates of granulocytic ehrlichiae in the United States. These characteristics suggest that this GE typing method may be an important epizootiological and epidemiological tool.  相似文献   
85.
BACKGROUND: The applications of new diagnostic technologies such as near patient tests are relevant to the further development and potential of primary care. Through their use, doctors in the community may increase the accuracy of their diagnoses and improve their ability to monitor disease. A reliable indicator of disease activity in various clinical conditions is C-reactive protein (CRP) and a near patient test for this is now available, although there is little information on its use outside hospitals. AIM: A study was set up to evaluate the feasibility of using a novel near patient test for CRP in primary care to validate the results against the laboratory "gold standard' for CRP (Beckman Array) and to compare results with the usual inflammation test used in general practice. METHOD: Prospective recording of CRP as a near patient test on an "intention to investigate' basis, with validation of results against the Beckman Array system for CRP and hospital laboratory erythrocyte sedimentation rate results, in six general medical practices in Birmingham. Main outcome measures were change in local laboratory usage, characteristics of patients chosen for testing, use of quality control, and comparison of readings with results from the same sample sent to an independent laboratory. RESULTS: Tests of CRP levels were rarely requested before the study was undertaken. During the 3-month study period, 181 near patient tests were carried out, 146 (81%) to establish a diagnosis and the remainder for disease monitoring. Out of the tests, 67% were performed by general practitioners, mostly during the consultation itself. Using a cut-off level of 10 mg I-1, the near patient test and the Beckman Array gave results which agreed in 84% of cases. The sensitivity and specificity of the near patient test results were 97 and 79%, respectively. The predictive value of a positive result was 59% and that of a negative result was 99%. Cohen's Kappa was 62% and the overall mean bias for results in the range of the test was 6.11 mg I-1 (SE = 3.07 mg I-1). Each test took 6 min on average to perform, including all preparations, blood letting, performing the test and averaging the time for quality control estimations. The cost per test averaged pounds 1.72, rising to pounds 4.17 including labour, capital costs, quality controls and consumables (general practitioner performing the assay at average frequency found in this study). CONCLUSIONS: Measurement of CRP is rarely used in primary care and awareness of its value could be raised. This near patient test proved feasible for use by general practitioners and practice nurses. Its reliability compared with a laboratory result was satisfactory overall, and excellent with adequate operator technique.  相似文献   
86.
Translocation (14;19)(q32;q13.1) is an acquired chromosomal rearrangement that has been associated with chronic lymphocytic leukemia of B-cell phenotype frequently progressing to lymphoma. Molecular analysis suggests that the translocation involves the immunoglobulin heavy chain gene on chromosome 14 and the BCL3 oncogene on chromosome 19. We present the first case of t(14;19) in a patient with acute leukemia. Correlation of detailed cytogenetic and molecular genetic studies, cell surface marker analysis, cytochemistry, and electron microscopy indicated that the leukemic cells were biophenotypic, with characteristics consistent with both myeloid and B-lineage lymphoid differentiation.  相似文献   
87.
88.
The spirochete Borrelia hermsii avoids the immune response of its mammalian host through multiphasic antigenic variation. Serotype specificity is determined by variable antigens, Vmp proteins, in the outer membrane. Through nonreciprocal recombination between linear plasmids, a formerly silent vmp gene replaces another vmp gene downstream from a common expression site. To further characterize this activating site, we determined the nucleotide sequence of 6.9 kb of the common upstream expression region of strain HS1 of B. hermsii. Preceding the vmp gene promoter and a poly(dT.dA) run were three imperfectly repeated segments of 2 kb. Each of the 2-kb segments contained 1-kb elements with inverted repeats of approximately 0.2 kb each at their termini. The potential of the 1-kb elements to form stem-and-loop structures was demonstrated by heteroduplex analysis. There was no evidence of the presence of the elements elsewhere in the genome of B. hermsii. One or more of these elements may confer the unidirectionality that characterizes vmp gene switches.  相似文献   
89.
Inhibition of cellular transformation by the adeno-associated virus rep gene   总被引:17,自引:0,他引:17  
S N Khleif  T Myers  B J Carter  J P Trempe 《Virology》1991,181(2):738-741
  相似文献   
90.
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