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71.
Blinded, Externally Controlled Multicenter Evaluation of Light Microscopy and PCR for Detection of Microsporidia in Stool Specimens 总被引:6,自引:4,他引:6 下载免费PDF全文
Heinz Rinder Klaus Janitschke Horst Aspck Alexandre J. Da Silva Peter Deplazes Daniel P. Fedorko Caspar Franzen Ursula Futh Frank Hünger Anselm Lehmacher Christian G. Meyer Jean-Michel Molina Jrg Sandfort Rainer Weber Thomas Lscher the Diagnostic Multicenter Study Group on Microsporidia 《Journal of clinical microbiology》1998,36(6):1814-1818
The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where technicians used light microscopy and for six laboratories where technicians used PCR. The average overall sensitivities were 67% (89% for patient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities were 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used. 相似文献
72.
Genes encoding the common gonadotrophin subunit and folliclestimulating hormone (FSH)-specific ß subunit wereisolated from a DNA library derived from human fetal liver cells,and inserted into separate expression vectors containing a selectable/amplifiablegene. These vectors were inserted into the genome of the Chinesehamster ovary cell line, resulting in expression of large amountsof biologically active human (h)FSH. This cell line was culturedon microcarrier beads in a large-scale bioreactor. hFSH in thecell culture supernatant was purified to homogeneity by a multistepprocess. The mature ß subunit had seven fewer aminoacid residues than reported in the literature and three otherdifferences were found in the sequence. Similar oligosaccharidestructures were present on recombinant (r)-hFSH and a purifiedurinary (u)-hFSH preparation. In-vitro and in-vivo, the biologicalactivities of u- and r-hFSH were indistinguishable, r-hFSH wasformulated in ampoules containing 75 IU FSH activity ( 7.5 µgFSH), which accounts for >99% of the protein content of thepreparation. Studies in non-human primates and human volunteersshowed the pharmacokinetics of u- and r-hFSH to be similar.In healthy volunteers, r-hFSH stimulated follicular developmentand induced significant increases in serum oestradiol and inhibin.Clinical experience with r-hFSH has shown it is more effectiveat stimulating ovarian follicle growth than urinary gonadotrophins.It is also effective at initiating spermatogenesis when giventogether with human chorionic gonadotrophin. 相似文献
73.
Wolf Szmuness Cladd E. Stevens Edward J. Harley Edith A. Zang Patricia E. Taylor Harvey J. Alter The Dialysis Vaccine Trial Group 《Journal of medical virology》1981,8(2):123-129
Three hundred thirty-six medical personnel from hemodialysis centers were treated with three doses, 20 μg each, of the Merck hepatitis B vaccine (at 0, 1, and 6 months). Within 1 month after the first injection, 41% converted to anti-HBs positivity; after the second injection the conversion rate rose to 80–90%; and after the booster, to 96–98%. The later rate remained unchanged during the 18-month follow-up period. Only 2.8% of those vaccinated did not respond to the vaccine. The patterns of immune responses to 20-μg doses were found to be exactly the same as to 40-μg doses. It is suggested that reduced doses of vaccine should be as efficacious as the larger ones. 相似文献
74.
Genetic diversity among community methicillin-resistant Staphylococcus aureus strains causing outpatient infections in Australia 下载免费PDF全文
Coombs GW Nimmo GR Bell JM Huygens F O'Brien FG Malkowski MJ Pearson JC Stephens AJ Giffard PM;Australian Group for Antimicrobial Resistance 《Journal of clinical microbiology》2004,42(10):4735-4743
Increasing reports of the appearance of novel nonmultiresistant methicillin-resistant Staphylococcus aureus MRSA (MRSA) strains in the community and of the spread of hospital MRSA strains into the community are cause for public health concern. We conducted two national surveys of unique isolates of S. aureus from clinical specimens collected from nonhospitalized patients commencing in 2000 and 2002, respectively. A total of 11.7% of 2,498 isolates from 2000 and 15.4% of 2,486 isolates from 2002 were MRSA. Approximately 54% of the MRSA isolates were nonmultiresistant (resistant to less than three of nine antibiotics) in both surveys. The majority of multiresistant MRSA isolates in both surveys belonged to two strains (strains AUS-2 and AUS-3), as determined by pulsed-field gel electrophoresis (PFGE) and resistogram typing. The 3 AUS-2 isolates and 10 of the 11 AUS-3 isolates selected for multilocus sequence typing (MLST) and staphylococcal chromosomal cassette mec (SCCmec) analysis were ST239-MRSA-III (where ST is the sequence type) and thus belonged to the same clone as the eastern Australian MRSA strain of the 1980s, which spread internationally. Four predominant clones of novel nonmultiresistant MRSA were identified by PFGE, MLST, and SCCmec analysis: ST22-MRSA-IV (strain EMRSA-15), ST1-MRSA-IV (strain WA-1), ST30-MRSA-IV (strain SWP), and ST93-MRSA-IV (strain Queensland). The last three clones are associated with community acquisition. A total of 14 STs were identified in the surveys, including six unique clones of novel nonmultiresistant MRSA, namely, STs 73, 93, 129, 75, and 80slv and a new ST. SCCmec types IV and V were present in diverse genetic backgrounds. These findings provide support for the acquisition of SCCmec by multiple lineages of S. aureus. They also confirm that both hospital and community strains of MRSA are now common in nonhospitalized patients throughout Australia. 相似文献
75.
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77.
Performance and Cost evaluation of one commercial and six in-house conventional and real-time reverse transcription-pcr assays for detection of severe acute respiratory syndrome coronavirus 总被引:5,自引:0,他引:5 下载免费PDF全文
78.
Blacker D Bertram L Saunders AJ Moscarillo TJ Albert MS Wiener H Perry RT Collins JS Harrell LE Go RC Mahoney A Beaty T Fallin MD Avramopoulos D Chase GA Folstein MF McInnis MG Bassett SS Doheny KJ Pugh EW Tanzi RE;NIMH Genetics Initiative Alzheimer's Disease Study Group 《Human molecular genetics》2003,12(1):23-32
Alzheimer's disease (AD) is a devastating neurodegenerative disorder of late life with complex inheritance. Mutations in three known genes lead to the rare early-onset autosomal dominant form of AD, while a common polymorphism (epsilon 4) in the gene encoding apolipoprotein E (APOE ) is a risk factor for more typical late-onset (>60 years) AD. A recent study concluded that there are up to four additional genes with an equal or greater contribution to the disease. We performed a 9 cM genome screen of 437 families with AD, the full National Institute of Mental Health (NIMH) sample, which has been carefully ascertained, evaluated and followed by our group over the last decade. Performing standard parametric and non-parametric linkage analyses, we observed a 'highly significant' linkage peak by Lander and Kruglyak criteria on chromosome 19q13, which probably represents APOE. Twelve additional locations-on 1q23, 3p26, 4q32, 5p14, 6p21, 6q27, 9q22, 10q24, 11q25, 14q22, 15q26 and 21q22-met criteria for 'suggestive' linkage [i.e. two-point lod score (TLS) >/=1.9 and/or multipoint lod score (MLS) >/=2.2] in at least one of our analyses. Although some of these will surely prove to be false positives, these linkage signals should provide a valuable framework for future studies aimed at identifying additional susceptibility genes for late-onset AD. 相似文献
79.
BACKGROUND: The clinical efficacy and safety of a six-grass pollen allergoid has been studied. The advent of more exacting clinical guidelines and a better appreciation of the possible mechanisms of treatment prompted this reappraisal. METHODS: A 2-year double-blind multicentre placebo-controlled phase 3 clinical trial was undertaken in 154 patients suffering symptoms of rhinoconjunctivitis with or without asthma (GINA I or II). Therapy comprised two consecutive preseasonal short-courses of subcutaneous injections using a grass pollen allergoid adsorbed to aluminium hydroxide. RESULTS: A combined symptom and medication score (SMS) was used as the primary end-point for clinical efficacy. SMS from the first year showed a significant difference of 26.6% between the two study groups (P=0.026) and this was improved after the second year when there was a 48.4% difference in SMS between active and placebo treatment in favour of the allergoid (P = 0.018). Highly significant increases in grass pollen allergen-specific IgG1 and IgG4 antibody concentrations were measured in association with active treatment. Allergen tolerance was increased as judged by a conjunctival provocation test and significant improvements in quality of life were documented using a standardized questionnaire. The allergoid was well tolerated. CONCLUSIONS: The grass pollen allergoid was shown to be safe and clinically efficacious in the management of hay fever with or without asthma (GINA I or II). 相似文献
80.
George Capone Mary Stephens Stephanie Santoro Brian Chicoine Peter Bulova Moya Peterson Joan Jasien Anna Jo Smith Down Syndrome Medical Interest Group Adult Health Workgroup 《American journal of medical genetics. Part A》2020,182(7):1832-1845
Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed. 相似文献