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461.
A cost-effective, reliable, and reproducible method has been developed to produce good-quality, double-stranded plasmid DNA
for automated sequence analysis. The method incorporates modifications to a previously described plasmid-purification protocol
used in manual sequencing. The quality of the DNA produced from the present protocol is suitable for automated fluorescent
sequencing. Using a dye-terminator sequencing protocol, most runs using plasmid DNA prepared using this protocol produced
over 700 bases with greater than 99% base-calling accuracy. 相似文献
462.
An automated cell analysis system (Autoplan-MIAC) for the early detection of precancerous lesions of the cervix was tested under semi-routine conditions in a clinical cytology laboratory. A set of 1500 specimens, highly enriched with abnormal cases, was analysed. Cervical scrapings were collected in suspension and processed by cytocentrifugation for microscopy. Two slides were prepared from each sample: one for staining according to Papanicolaou for the visual reference diagnosis and one for Feulgen staining for automated analysis. the specimens were evaluated in two ways: the first one, which is referred to as the automated machine classification system (AMC), classifies the specimens according to the number and ratio of selected objects (alarms) and is a fully automated system. the second system classifies the specimens after visual evaluation of the stored alarms as they are displayed on a TV monitor, and is designated the interactive machine classification system (IMC). the AMC results showed a false positive rate of 16.5% when the cut-off threshold was selected so that all 117 positively diagnosed specimens were classified ‘positive’ by the system. In that case 87.4% of the CINI and 96.9% of the CINII cases were AMC-positive. the IMC results showed a false positive rate of 2.5%, when 86.3% of the CIN I cases, 96.9% of the CIN II cases and all CIN III and invasive carcinoma cases were positively classified. 相似文献
463.
Hiroaki Mikasa Yasuo Suzuki Nobuo Fujii Keitaro Nishiyama 《Biological trace element research》1988,16(1):59-66
The adsorption of zinc and lead on hair was dependent on the acidity of the hair and/or the medium in which the hair sample
was immersed, suggesting that hair is an ion exchanger. The pKa was estimated to be between 4.5 and 5.0. The coexistence of
mercuric ion or PCMB reduced zinc adsorption by only a few percent, whereas zinc inhibited mercuric ion adsorption to a greater
extent. These facts suggest that the binding sites in hair for metals are located on functional groups like carboxyl groups
rather than sulfhydryl groups.
The removal and/or elution of metals from hair were observed for 18 elements by various washing procedures. By treating hair
with a water solution of detergent, alkaline metals were eluted to a great extent, whereas alkaline earth metals were eluted
to some extent. The other metals did not vary with any procedures tested. 相似文献
464.
Umeo Takahama 《Physiologia plantarum》1993,89(4):791-798
The aqueous phase of cell walls in stems of Kalanchoë daigremontiana Hamet et Perrier de la Bâthie (apoplast) contained ascorbic acid (AA) and dehydroascorbic acid (DHA). Ratios of AA/(AA + DHA) were 0.31 ± 0.12 (SD, n = 4), whereas those of whole stems (tissues plus apoplast) were >0.9. The amounts of (AA + DHA) in the stems were 1970 ± 190 (SD, n = 4) nmol g−1 fresh weight and those in the apoplast were 14 ± 2 (SD, n = 4) nmol g−1 fresh weight of stems. Ratios of AA/(AA + DHA) differed in different tissues of the stems. The ratios of AA/(AA + DHA) of apoplast plus symplast were in the following order: pith ⋍ epidermis plus cortex > vascular bundle system, and those of apoplast were: pith > epidermis plus cortex > vascular bundle system. Ratios of AA/(AA + DHA) in the apoplast of the different tissues decreased to about 1/3 of the original values after wounding, while the amounts of (AA + DHA) remained largely unaffected. In contrast, soluble apoplastic peroxidase activities increased 30- to 70-fold on wounding. Hydrogen peroxide infiltrated into stems caused a rapid oxidation of AA. Coniferyl alcohol was oxidized by peroxidase in intercellular washing fluid and by cell wall-bound peroxidase. The oxidation of coniferyl alcohol by peroxidase in intercellular washing fluid was completely inhibited as long as AA was present in reaction mixtures. The oxidation of the coniferyl alcohol by cell wall-bound peroxidase was partially inihibited by AA and the degree of inhibition was dependent upon the concentration of AA. The possible functions of AA in the apoplast are discussed in relation to the control of peroxidase-dependent oxidation of phenolics. 相似文献
465.
Michal Lebl Christine Pistek John Hachmann Petr Mudra Vaclav Pesek Vit Pokorny Pavel Poncar Karel Zenisek 《International journal of peptide research and therapeutics》2007,13(1-2):367-375
We have developed a small benchtop oligonucleotide synthesizer which allows the scientist to prepare, rapidly and economically,
up to 24 oligonucleotides in one batch. We have shown that this instrument can be used for peptide synthesis, as well. The
instrument is based on the centrifugation method for solid–liquid separation.
Dedicated to the memory of Prof. Bruce Merrifield, who was the inspiration behind all of our efforts in building automatic
synthesizers. 相似文献
466.
467.
- In the context of global amphibian decline, monitoring and restoration programmes are important. Acoustic monitoring is a possible approach for underwater vocalising species like the rapidly declining European common spadefoot toad (Pelobates fuscus). In this study, our aim was to design a dedicated software detector to be used in combination with programmable audio recorders to process the large amount of data generated by long-term acoustic monitoring and to use it for investigating the seasonal and circadian patterns of P. fuscus vocal activity.
- The software detector targets advertisement calls of the species. Based on acoustic analysis of that call, we developed a detector that utilises both frequency and time features of the calls. Data collected during three breeding seasons in four known or potential P. fuscus breeding sites of north-eastern France were used to build a ground truth in order to test the performance of the detector. Then, we used the detector for analysing four acoustic monitoring campaigns conducted in two different sites over two breeding seasons to gain insight into the seasonal and circadian patterns of vocal activity of this species.
- Evaluation of the P. fuscus call detector against a ground truth returned false-positive rates below 1.5% and true-positive rates ranging from 53% to 73%. These figures are compatible with long-term monitoring of the presence of the species. Running the software detector on standard hardware, the computation time for post-processing the 360 hr of a typical 3-month monitoring campaign was less than 1 day.
- The seasonal pattern of P. fuscus underwater vocal activity is more complex than previously recognised. Over the whole ostensible 3-month breeding season, the actual time window for vocalising and breeding can last from a few days up to several weeks and may be split into clearly distinct episodes. When vocalisations occurred at both night- and daytime, the circadian vocal activity of P. fuscus occasionally proceeded uninterrupted for 24 hr but usually a several hour lull occurred immediately prior to sunset. When vocalisations occurred at both night- and daytime, the vocal activity pattern followed a bimodal distribution with a nocturnal highest peak of activity and a second peak occurring in the morning.
- Our results demonstrate that it is feasible to monitor presence of P. fuscus in north-eastern France using a dedicated software detector combined with programmable audio recorders. Based on the outcomes of the detector applied to long-term audio data sets, we reveal temporal patterns of the vocal activity of the species and subsequently provide recommendations for attended and unattended acoustic monitoring.
468.
《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