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11.
Point prevalence of oropharyngeal carriage of fluconazole-resistant Candida in human immunodeficiency virus-infected patients 总被引:1,自引:0,他引:1
To estimate the prevalence of both clinically evident and asymptomatic carriage of fluconazole-resistant Candida, we prospectively surveyed 128 adults infected with human immunodeficiency virus (HIV). The patients had an average CD4 cell count of 206/mm3. Ninety-seven isolates of Candida were obtained from the oropharynx of 82 patients (64%). Of these 82 patients, 76% carried C. albicans alone; 18%, both albicans and non-albicans isolates; and 6%, non-albicans species alone. Oropharyngeal candidiasis was evident in only 38 (46%) of the 82 patients for whom a culture was positive and was never seen unless C. albicans was present. When MICs were measured by using the National Committee for Clinical Laboratory Standards M27-T methodology and grouped by using recently proposed breakpoints, we found that eight of the 38 patients with oropharyngeal candidiasis and six of the 44 patients who were asymptomatically colonized carried C. albicans isolates resistant to fluconazole (MIC, > or = 64 micrograms/mL); estimated rates of carriage were 21% (95% confidence interval, 10%-37%) and 14% (95% confidence interval, 5%-27%), respectively. Carriage of resistant isolates of C. albicans by HIV-infected adults is more common than previously suspected, and clinicians should be alert to the possible need for either higher doses of fluconazole or alternative treatment modalities. 相似文献
12.
Cristiane Vieira Helm Alicia de Francisco Salete Aparecida Gaziola Ricardo Francisco Fornazier Georgia Bertoni Pompeu Ricardo Antunes Azevedo 《Food Biotechnology》2005,18(3):327-341
Barley (Hordeum vulgare L.) has had an important impact on human nutrition. Hull-less barley is a genetically improved type that has been widely used in recent years. Six Brazilian hull-less barley varieties (IAC-IBON 214-82; IAC 8612-421; IAC 8501-31; IAC 8501-12; IAPAR 39-ACUMAI; IAC 8501-22) were analyzed for storage protein constituents, amino acid contents, and similarity among the hull-less barley varieties. Albumins, globulins, prolamins I and II, and glutelins were extracted and separated by SDS-PAGE. The total protein amino acid contents of the flour were also determined for each variety by TLC and HPLC. Variations in intensity and appearance and disappearance of protein bands were observed among the varieties suggesting genetic variability. However, the amino acid profile did not indicate any major variations in the amino acid concentrations. The high lysine and threonine total concentrations detected in the seeds of the hull-less barley varieties encouraged an investigation into the regulation of amino acid metabolism and storage protein synthesis. 相似文献
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Two-step channel selection-a novel technique for reconfigurable multistandard transceiver front-ends
Pui-In Mak Seng-Pan U Martins R.P. 《IEEE transactions on circuits and systems. I, Regular papers》2005,52(7):1302-1315
This paper starts with a review of the prevailing channel-selection techniques utilized so far in the design of wireless transceiver analog front-ends before describing a novel two-step channel-selection technique, which handles the traditionally unwanted image, in radio frequency-to-intermediate frequency (RF-to-IF) or IF-to-RF frequency conversion, as a useful adjacent channel of the desired one, and selects deliberately either of them from IF to baseband (or baseband to IF). Thus, one more channel-selection possibility is created for both low-IF receivers and two-step-up transmitters. The consequential benefits of introducing channel selection at IF consist of two. First, many design specifications (such as phase noise and settling time) of the RF frequency synthesizer and local oscillator can be substantially relaxed. Second, a low-IF/zero-IF reconfigurable receiver and a direct-up/two-step-up reconfigurable transmitter can be synthesized to match better with narrowband-wideband-mixed multistandard systems. The operating principles of such architectures are presented in easy-to-understand complex-signal spectral-flow illustrations, and their practicability is demonstrated in the design of a Bluetooth/IEEE 802.11FH/HomeRF multistandard receiver. SPECTRE simulation results validate the reconfigurable functionalities mainly implemented by a triple-mode channel-select filter and a multifunctional sampling-mixer scheme. 相似文献
16.
Raquel Alves dos Santos Teresinha Rosa Cabral Isabel Rosa Cabral Lusania Maria Greggi Antunes Cristiane Pontes Andrade Plínio Cerqueira dos Santos Cardoso Marcelo de Oliveira Bahia Claudia Pessoa José Luis Martins do Nascimento Rommel Rodríguez Burbano Catarina Satie Takahashi 《Biocell》2008,32(2):195-200
Physalis angulata L (Solanaceae) is a medicinal plant from North of Brazil, whose different extracts and infusions are commonly used in the popular medicine for the treatment of malaria, asthma, hepatitis, dermatitis and rheumatism. However, the genotoxic effects of P. angulata on human cells is not well known. The main purpose of the present study was to evaluate the in vitro genotoxic effects of aqueous extract of P. angulata using the comet assay and the micronucleus assay in human lymphocytes provided from 6 healthy donors. Treatments with P. angulata extracts were performed in vitro in order to access the extent of DNA damage. The comet assay has shown that treatments with P. angulata at 0.5, 1.0, 2.0, 3.0 and 6.0 microg/mL in culture medium were genotoxic. Lymphocytes treated with P. angulata at the concentrations of 3.0 and 6.0 microg/mL in culture medium showed a statistically significant increase in the frequency of micronucleus (p<0.05), however, the cytokinesis blocked proliferation index (CBPI) was not decreased after P. angulata treatment. In conclusion, the present work demonstrated the genotoxic effects of P. angulata extract on human lymphocytes in vitro. 相似文献
17.
Heloisa Martins Shih Mitchell M Tseng 《International Journal of Project Management》1996,14(6):373-378
In this paper the application of workflow technology to monitor, control and coordinate business processes and projects is proposed. The conceptual characteristics of processes and projects as well as their management needs in the functions of planning, execution, monitoring and control are compared. The general design of the proposed system is then developed, with an application example. The proposed monitoring and control system provides proactive tracking of the flow of work and information, and of the utilization and commitment of resources. The design supports hierarchical management of the project and/or business process, allowing concerned persons to visualize and to utilize it in different levels of abstraction, as necessary. The application of workflow technology also provides additional benefits in facilitating communication, documentation and re-utilization. 相似文献
18.
T Paiva A Farinha A Martins A Batista C Guilleminault 《Canadian Metallurgical Quarterly》1997,157(15):1701-1705
BACKGROUND: Headaches and sleep problems are common complaints in the daily practice of the general practitioner. Since the relationship between headaches and sleep complaints is complex, clear models of interaction are needed for adequate diagnosis and treatment. METHODS: All subjects, successively seen in a headache clinic during a defined period, were subdivided based on the time of onset of cephalalgia. Subjects who reported onset of headache on a long-term basis, during the nocturnal or early morning (before final awakening) period, were systematically studied by a headache clinic and a sleep disorders center. This subgroup represented 17% of the total headache group. RESULTS: Although the results of the headache clinic study did not differentiate this subgroup from the other patients, the sleep disorders center's interviews and questionnaires demonstrated a significant impact of the sleep disorders on headache and daytime function. Nocturnal monitoring during sleep identified specific sleep disorders in 55% of the subjects with onset of headache during the nocturnal sleep period. Follow-up after treatment of the sleep disorder showed that all subjects with an identifiable sleep disorder reported either an improvement or absence of their headache. The subjects identified with periodic limb movement syndrome were mostly those who reported only an improvement in their sleep and still needed treatment for their headaches. The question of the interaction and association of sleep-related headache and periodic limb movement syndrome is unresolved. CONCLUSION: Headaches occurring during the night or early morning are often related to a sleep disturbance. 相似文献
19.
Peter J. Jervis Carolina Amorim Teresa Pereira Jos A. Martins Paula M. T. Ferreira 《International journal of molecular sciences》2021,22(5)
Supramolecular peptide hydrogels are gaining increased attention, owing to their potential in a variety of biomedical applications. Their physical properties are similar to those of the extracellular matrix (ECM), which is key to their applications in the cell culture of specialized cells, tissue engineering, skin regeneration, and wound healing. The structure of these hydrogels usually consists of a di- or tripeptide capped on the N-terminus with a hydrophobic aromatic group, such as Fmoc or naphthalene. Although these peptide conjugates can offer advantages over other types of gelators such as cross-linked polymers, they usually possess the limitation of being particularly sensitive to proteolysis by endogenous proteases. One of the strategies reported that can overcome this barrier is to use a peptidomimetic strategy, in which natural amino acids are switched for non-proteinogenic analogues, such as D-amino acids, β-amino acids, or dehydroamino acids. Such peptides usually possess much greater resistance to enzymatic hydrolysis. Peptides containing dehydroamino acids, i.e., dehydropeptides, are particularly interesting, as the presence of the double bond also introduces a conformational restraint to the peptide backbone, resulting in (often predictable) changes to the secondary structure of the peptide. This review focuses on peptide hydrogels and related nanostructures, where α,β-didehydro-α-amino acids have been successfully incorporated into the structure of peptide hydrogelators, and the resulting properties are discussed in terms of their potential biomedical applications. Where appropriate, their properties are compared with those of the corresponding peptide hydrogelator composed of canonical amino acids. In a wider context, we consider the presence of dehydroamino acids in natural compounds and medicinally important compounds as well as their limitations, and we consider some of the synthetic strategies for obtaining dehydropeptides. Finally, we consider the future direction for this research area. 相似文献
20.
Joseph Breheny Cian Kingston Robert Doran Joao Anes Marta Martins Samus Fanning Patrick J. Guiry 《International journal of molecular sciences》2021,22(12)
Herein, we report antibacterial and antifungal evaluation of a series of previously prepared (+)-tanikolide analogues. One analogue, (4S,6S)-4-methyltanikolide, displayed promising anti-methicillin-resistant Staphylococcus aureus activity with a MIC of 12.5 µg/mL. Based on the antimicrobial properties of the structurally related (−)-malyngolide, two further analogues (4S,6S)-4-methylmalyngolide and (4R,6S)-4-methylmalyngolide bearing a shortened n-nonyl alkyl side chain were prepared in the present study using a ZrCl4-catalysed deprotection/cyclisation as the key step in their asymmetric synthesis. When these were tested for activity against anti-methicillin-resistant Staphylococcus aureus, the MIC increased to 50 µg/mL. 相似文献