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1.
Rolando Barbucci Mario Casolaro Mila Nocentini Gianna Reginato Paolo Ferruti 《Macromolecular chemistry and physics.》1986,187(8):1953-1962
Two linear vinyl polymers carrying amido and primary amino groups in the side chains were synthesized and characterized. Their behaviour in aqueous solution was investigated by potentiometric, viscometric and calorimetric techniques. In both cases, the basicity constants show a linear dependence on the degree of protonation α, while the enthalpy values of protonation do not. The thermodynamic results demonstrate the important role of hydrophobic interactions on the protonation process. 相似文献
2.
Dejan Popovic Tessa Gordon Victor F. Rafuse Dr. Arthur Prochazka 《Annals of biomedical engineering》1991,19(3):303-316
Implanted wire electrodes are increasingly being used for the functional electrical stimulation of muscles in partially paralysed
patients, yet many of their basic characteristics are poorly understood. In this study we investigated the selectivity, recruitment
characteristics and range of control of several types of electrode in triceps surae and plantaris muscles of anaesthetized
cats. We found that nerve cuffs are more efficient and selective (i.e., cause less stimulus spread to surrounding muscles)
than intramuscular electrodes. Bipolar intramuscular stimulation was more efficient and selective than monopolar stimulation,
but only if the nerve entry point was between the electrodes. Monopolar electrodes are efficient and selective if located
close to the nerve entry point, but their performance declines with distance from it. Nonetheless, for a variety of reasons
monopolar stimulation provides the best compromise in many current applications. Short duration pulses offer the best efficiency
(least charge per pulse to elicit force) but high peak currents, increasing the risk of electrode corrosion and tissue damage.
Electrode size has little effect on recruitment and should therefore be maximised because this minimises current density. 相似文献
3.
Sarah L. Nolin Anne Glicksman Nicole Tortora Emily Allen James Macpherson Montserrat Mila Angela M. Vianna‐Morgante Stephanie L. Sherman Carl Dobkin Gary J. Latham Andrew G. Hadd 《American journal of medical genetics. Part A》2019,179(7):1148-1156
Instability of the FMR1 repeat, commonly observed in transmissions of premutation alleles (55–200 repeats), is influenced by the size of the repeat, its internal structure and the sex of the transmitting parent. We assessed these three factors in unstable transmissions of 14/3,335 normal (~5 to 44 repeats), 54/293 intermediate (45–54 repeats), and 1561/1,880 premutation alleles. While most unstable transmissions led to expansions, contractions to smaller repeats were observed in all size classes. For normal alleles, instability was more frequent in paternal transmissions and in alleles with long 3′ uninterrupted repeat lengths. For premutation alleles, contractions also occurred more often in paternal than maternal transmissions and the frequency of paternal contractions increased linearly with repeat size. All paternal premutation allele contractions were transmitted as premutation alleles, but maternal premutation allele contractions were transmitted as premutation, intermediate, or normal alleles. The eight losses of AGG interruptions in the FMR1 repeat occurred exclusively in contractions of maternal premutation alleles. We propose a refined model of FMR1 repeat progression from normal to premutation size and suggest that most normal alleles without AGG interruptions are derived from contractions of maternal premutation alleles. 相似文献
4.
N. Matamoros Florí J. Mila Llambi T. Español Boren S. Raga Borja G. Fontan Casariego 《Journal of clinical immunology》1997,17(4):333-339
The Spanish Registry for Primary Immunodeficiency Diseases (REDIP) was organized in 1993. One thousand sixty-nine cases of primary immunodeficiency diseases (PID) were registered in patients diagnosed between January 1980 and December 1995. PID diagnosis was made according to the World Health Organization criteria. The most frequent disorders were IgA deficiency (n = 394) and common variable immunodeficiency (n = 213), followed by severe combined immunodeficiency (n = 61), C1 inhibitor deficiency (n = 52), X-Iinked agammaglobulinemia (n = 49), IgG subclass deficiency (n = 48), and chronic granulomatous disease (n = 32). A comparative study between REDIP and data recently obtained from the European registry (ESID Report, 1995) revealed important differences between phagocytic disorders and complement deficiencies reported in both registries, 4.9 vs 8.7 and 6.0 vs 3.6, while percentages of predominantly antibody deficiencies and T cell and combined deficiencies concurred with those reported in the European registry, 69.3 vs 64.7 and 14.7 vs 20.2, respectively. The heterogeneous nature of the geographical distribution of cases submitted may indicate underdiagnosis of PID in some country areas; surprisingly, the interval between the onset of clinical symptoms and diagnosis was significant, even in immunodeficiency diseases, such as IgA deficiency, which are easy to diagnose. 相似文献
5.
Dejan Nikolic Yongmei Li Lucas R Chadwick Simonida Grubjesic Pia Schwab Peter Metz Richard B van Breemen 《Drug metabolism and disposition》2004,32(2):272-279
The female flowers of hops are used throughout the world as a flavoring agent for beer. Recently, there has been increasing interest in the potential estrogenic properties of hop extracts. Among the possible estrogenic compounds in hops, 8-prenylnaringenin is perhaps most significant due to its high in vitro potency exceeding that of other known phytoestrogens. Since data regarding the pharmacokinetic properties of this compound are lacking, we investigated the in vitro metabolism of 8-prenylnaringenin by human liver microsomes. A total of 12 metabolites were identified, and biotransformation occurred on the prenyl group and the flavanone skeleton. The major site of oxidation was on the terminal methyl groups, and of the two possible isomers, the transisomer was more abundant. The double bond on the prenyl group was also oxidized to an epoxide that was opened by intramolecular reaction with the neighboring hydroxyl group. On the flavanone skeleton, the major site of oxidation was at 3'position on the B ring. Other metabolites included oxidation at carbon-3 as well as desaturation of the C ring to produce 8-prenylapigenin. An unusual hydroxy quinone product formed by ipso hydroxylation of the B ring of 8-prenylnaringenin was also detected. This product was probably an intermediate for the B ring cleavage product, 8-prenylchromone. 相似文献
6.
7.
Karen Marr Dejan Jakimovski Marcello Mancini Ellen Carl Robert Zivadinov 《Ultrasound in medicine & biology》2018,44(8):1762-1769
A consensus on venous flow quantification using echo spectral Doppler sonography is lacking. Doppler sonography data from 83 healthy individuals were examined using manually traced transverse cross-sectional area and diameter-derived cross-sectional area obtained in longitudinal view measurements of the internal jugular vein. Time-averaged velocity over a 4-s interval was obtained in the longitudinal plane using manual tracing of the waveform. Manual and computer-generated blood flow volume calculations were also obtained for the common carotid artery, for accuracy purposes. No differences were detected between semi-automated and manual blood flow volume calculations for the common carotid artery. The manual calculation method resulted in almost twofold larger venous internal jugular vein flow measurements compared with the semi-automated method. Doppler sonography equipment does not provide accurate automated calculation of venous size and blood flow. Until further technological development occurs, manual calculation of venous blood flow is warranted. 相似文献
8.
Uroš Rajkovič Marija Milavec Kapun Dejan Dinevski Vesna Prijatelj Marija Zaletel Olga Šušteršič 《Journal of medical systems》2016,40(9):198
Health documentation is a prerequisite for good and sustainable health and social care. It is especially important for patient involvement and their empowerment. A transition from paper to e-documentation together with the electronic patient record should be based on thorough knowledge of the current state of documentation and its usages. The main objective of this paper was to analyse which documents and work methods of documenting processes within nursing are being used within different environments. Furthermore, what are the main reasons for their discrepancies from theoretical approaches and best practices. The analysis is based on a survey carried out on all three levels of healthcare. The survey questionnaire consisted of 12 questions to which responded 286 nursing teams from community health centres, hospitals and retirement homes in Slovenia. The results point to diversity in documenting as well as lack of interoperability. This is reflected in a great number of different documents. All phases of the nursing process were being documented in only 31.8 % of cases. The main reasons for this can be attributed to work organisation, different definitions of data-set requirements and inadequate knowledge by nurses. Survey results pointed out a need for the renewal of nursing documentation towards a more uniform system based on contemporary health technologies. 相似文献
9.
Dejan Susic Bo Rønn Hansen Torben Bæk Hansen 《Journal of plastic surgery and hand surgery》2013,47(3):319-320
To find out if a non-invasive technique (ultrasonography) was able to identify a dislocated ligament of a metacarpophalangeal joint of the thumb with instability of the ulnar collateral ligament, 14 consecutive patients with clinical rupture of the ulnar collateral ligament were examined with ultrasono-graphy before the ligament was explored. At exploration all ligaments were ruptured, and only five out of the 14 were dislocated. Ultrasonography recognised only two of the dislocated ligaments, and in half of the 14 patients the ultrasound scan gave incorrect information about the position of the ligament. We conclude that ultrasonography is not adequate for identifying dislocated ulnar collateral ligaments of the metacarpophalangeal joint of the thumb, and exploration is indicated in those with clinical instability in which palpation either suggests a dislocated ligament or is inconclusive. 相似文献
10.