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721.
Rapid PCR test for Streptococcus suis serotype 7 总被引:5,自引:0,他引:5
Hilde E Smitha Linda van Bruijnsvoorta Herma Buijsa Henk J Wisselinka Mari A Smitsa 《FEMS microbiology letters》1999,178(2):265-270
Recent epidemiological studies on Streptococcus suis infections in pigs indicated that, besides serotypes 1, 2 and 9, serotype 7 is also frequently associated with diseased animals. For the latter serotype, however, no rapid and sensitive diagnostic methods are available. This hampers prevention and control programs. Here, we describe the development of a type-specific PCR test for the rapid and sensitive detection of S. suis serotype 7. The test is based on DNA sequences of capsular (cps) genes specific for serotype 7. These sequences were identified by cross-hybridization of several individual cps genes with the chromosomal DNAs of 35 different S. suis serotypes. 相似文献
722.
Manousos E Kambouris Utz Reichard Nicholas J Legakis Aristea Velegraki 《FEMS immunology and medical microbiology》1999,25(3):255-264
In immunodeficient patients, Aspergillus species emerge as circumstantial pathogens. Aspergillus fumigatus is a distant first among the pathogenic aspergilli, which cause deep-seated mycoses. Sequences of the pep gene of A. fumigatus as potential PCR primers, which have not been tested before, were used to identify this species and if possible, differentiate it from other, co-identified, clinically important species of the genus. We present results of the three most promising primer pairs, pep-1/pep-22, pep-15/pep-22 and pep-21/pep32. The second pair was of better specificity when tested with DNA extracted from pure cultures of a multitude of aspergilli, whereas the first co-amplified four clinically significant Aspergillus species. The compatibility of the PCR method with the CTAB DNA extraction protocol varied according to the biological fluid tested and the primer pair used. The first two pairs showed moderate adaptability to the different commercial DNA extraction kits, which were tested in whole blood, spiked with Aspergillus fumigatus hyphae and conidia - as were all the biological fluids used. Restriction of the amplification products with MspI produced distinct patterns for different Aspergillus spp. This approach, as a potential diagnostic tool, seems reliable and sensitive due to its flexibility, speed, low cost, ease of application and selectable breadth of detection. 相似文献
723.
Li-fang Zhang Wei-min Gao Robert Gealy Joel Weissfeld Elaine Elder Theresa L. Whiteside 《Biomarkers》2013,18(2):156-161
Mutations in the K-ras gene are frequently found in lung tumours and are implicated in the development of lung cancer. In order to investigate the clinical usefulness of these mutations in lung cancer, we applied a sensitive method to compare mutations in codon 12 of the K-ras gene in DNA extracted from lung tumours and the matched sputum samples obtained from 22 lung cancer patients. K-ras mutations were identified in the lung tumours of 12 patients (54.5%) and in the sputum samples of 10 patients (45.5%). Nine patients showed an identical mutation in both the tumour and the matched sputum samples. There was a significant association between the presence of a K-ras mutation in a lung tumour and the detection of an identical mutation in the matched sputum sample of the lung cancer patient (κ = 0.64, 95% confidence interval 0.32-0.95, p <0.01). K-ras mutations were detected in sputum samples from cancer patients with all lung tumour grades, and both in the presence and the absence of lymph node metastasis. Therefore, K-ras mutations may provide useful diagnostic markers for lung cancer. 相似文献
724.
725.
726.
A new set of primers for the detection of Toxoplasma gondii in amniotic fluid using polymerase chain reaction 总被引:1,自引:0,他引:1
Hervé Pelloux Judy Weiss Josiane Simon François Muet hélène Fricker-hidalgo rée Goullier-fleuret Pierre Ambroise-thomas 《FEMS microbiology letters》1996,138(1):11-15
Abstract A new PCR system including a pair of primers, a probe and an internal control were designed from the B1 gene of Toxoplasma gondii . The system described allowed the detection of less than 10 tachyzoites of the RH strain of T. gondii . Among 21 amniotic fluid samples, this system diagnosed the cases of congenital toxoplasmosis which were simultaneously diagnosed using mice inoculation, in vitro culture, and serology from both amniotic fluid and fetal blood. These results show that these new primers allow for a highly sensitive detection of T. gondii DNA. 相似文献
727.
目的:探讨并比较动态(电子)喉镜及电子喉镜诊断喉部疾病的临床价值。方法:回顾性分析2012-2013年东南大学附属南京江北人民医院和南京大学医学院附属鼓楼医院耳鼻咽喉科收治的1826例患者的内镜诊断及病理诊断资料,并对其结果进行相关比对分析。结果:电子喉镜诊断喉部病变的正确率为97.44%,良恶性病变的误诊率为1.84%,良恶性病变的诊断一致性为98.16%。动态(电子)喉镜诊断喉部病变的正确率为99.31%,良恶性病变的误诊率为0.35%,良恶性病变的诊断一致性为99.65%。结论:动态(电子)喉镜和电子喉镜诊断喉部病变均有很高的临床价值,动态(电子)喉镜优于电子喉镜。 相似文献
728.
《Endocrine practice》2023,29(1):24-28
BackgroundHybrid closed-loop (HCL) systems, also known as automated insulin delivery systems, are a rapidly growing technology in diabetes management. Because more patients are using these systems in the outpatient setting, it is important to also assess inpatient safety to determine whether HCL use can be continued when those patients become hospitalized.MethodsThe records of patients using HCL technology on admission to our hospital between June 1, 2020, and June 30, 2021, were analyzed.ResultsThe final analysis included 71 patients divided into 3 categories based on their pump use as an inpatient: (1) HCL users; (2) manual pump users; and (3) pump removed. All cohorts were similar in age, sex, race, hemoglobin A1C at admission, and in Medicare Severity Diagnosis Related Group. Pairwise comparisons indicated that patient-stay mean glucose levels, frequency of patient-specific hyperglycemic measurements, and frequency of hypoglycemic events were similar between all groups. No adverse events, particularly occurrences of diabetic ketoacidosis, pump site complications or infection, or equipment malfunction, were reported.ConclusionThis preliminary case series review indicates that continued use of HCL technology in the hospital is safe. Moreover, glycemic control in HCL users was comparable with that in those using insulin pump with manual settings and those converted to basal-bolus insulin therapy. 相似文献
729.
H. Ramírez B. San Romn I. Glaria R. Reina M.M. Hernndez X. de Andrs H. Crespo B. Hichou S. Cianca C. Goi A. Grandas L. García-Pastor L.E. Vijil F. Quintín M.J. Grill D. de Andrs B. Amorena 《Theriogenology》2009,72(8):1085-1096
Antibody-based diagnosis of small ruminant lentiviruses (SRLVs) has been efficiently achieved using serum and milk, but not semen, for which polymerase chain reaction (PCR) has been proposed as a confirmatory technique. This work, involving 296 ovine (Ovis aries) and caprine (Capra hircus) semen donors, investigates whether seminal fluid (SF) can be reliably used in antibody-based SRLV diagnosis. First, a gold standard was established to assess the infection status and determine the sensitivity and specificity of three commercial enzyme-linked immunosorbent assays (ELISAs) in serum testing using Western blot and PCR as confirmatory tests. For SF testing, both gold standard and serum testing results were used as reference. The performance of SF testing was affected not only by the ELISA assay sensitivity (related to antigen spectrum) compared with that of the gold standard (as it occurred in serum testing) but also by SF sample quality and SF working dilution. Nonturbid SF samples, commonly collected in artificial insemination centers (AICs), were required. Compared with serum, SF testing had a decreased sensitivity in two of the ELISA assays (with original serum working dilutions ≤1/20 in serum testing) but reached a similar sensitivity (and specificity) in the assay designed to work at the highest serum dilution (1/500). A SF concentration of about 1/2 (250-fold that used in serum testing) was found optimal in this assay, yielding highly repeatable results that were in almost perfect agreement with those of serum testing (κ ± SE, 0.91 ± 0.81). Thus, SF ELISA can be reliably applied in antibody-based SRLV diagnosis. This information may be useful to control infection in AICs and animal and semen trade programs requiring health-certified quality of semen donors. 相似文献
730.
Jacek Tomczyk Iulian Komarnitki Dorota Olczak‐Kowalczyk 《American journal of physical anthropology》2013,150(3):475-481
In many odontological studies concerning archeological material, there is no analysis of early caries lesions (caries incipiens) that manifest as a carious spot. At this stage of caries, the enamel is still hard, and thus, it is impossible to diagnose caries by visual methods. We assessed the usefulness of the DIAGNODent pen (DD laser) in analyzing noncavity lesions on the smooth surface sites of crowns from historical populations. Twenty‐seven individuals were examined: 18 from Radom (Poland), and nine from Tell Masaikh and Terqa (Syria). A total of 562 teeth were characterized. The series represented different climatic zones, but were dated from the similar period, 18th to 19th century AD. We used four diagnostic techniques: visual, DD laser, radiographic, and histological as the gold standard. DD laser showed that the mean values of healthy enamel in both series did not exceed 15 units. The mean values of smooth and rough spots in the Syrian population were significantly higher than those from Poland. This study showed that all the noncarious spots from the Radom series did not exceed 30 units. In the Syrian samples, this limit was higher at 44 units. These results were confirmed by histology and radiography. The DD laser provided good results in detecting dentine carious lesions in historical material, but its efficiency in diagnosing early caries (caries incipiens) remains uncertain based on the presented series. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc. 相似文献