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排序方式: 共有895条查询结果,搜索用时 31 毫秒
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.
Tozzi V Balestra P Galgani S Narciso P Sampaolesi A Antinori A Giulianelli M Serraino D Ippolito G 《Journal of acquired immune deficiency syndromes (1999)》2001,28(1):19-27
OBJECTIVES: To describe changes in HIV-associated neurocognitive impairment in patients treated with highly active antiretroviral therapy (HAART) for at least 3 years. METHODS: Prospective, observational study of comprehensive neuropsychologic (NP) testing, neurologic examination, and laboratory measures before HAART and after 6, 15 and 45 months of HAART, on 28 consecutive patients seen in our department since April 1996. RESULTS: At baseline, 16 patients were neurocognitively impaired and 12 were not. Among the 16 impaired patients, 5 patients failed to meet the criteria for impairment after 6 months and 9 patients after both 15 and 45 months of HAART, respectively. Statistically significant improvements ( p < or =.01) were seen in two of six measures exploring the concentration and speed of mental processing, two of three measures exploring mental flexibility, in one of five measures exploring memory, and in two of two measures exploring fine motor functions. Unimpaired study subjects performed better than impaired ones in 10 of 17 measures at baseline, in eight of 17 after 6 months, in six of 17 after 15 months, and in seven of 17 after 45 months of HAART. CONCLUSIONS: During the course of HAART, patients experienced a positive and sustained improvement in their neurocognitive performance. However, the presence of 7 of 16 (43.7%) patients with neurocognitive impairment, and the persistence of statistically significant differences in the neurocognitive performance between impaired and unimpaired patients after more than 3 years of HAART, suggests that ongoing HIV-related neurologic damage can occur even during potent antiretroviral treatment. 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.
General morphology and capsid fine structure of African swine fever virus particles 总被引:11,自引:0,他引:11
JoséL. Carrascosa JoséM. Carazo Angel L. Carrascosa Narciso García Antonio Santisteban Eladio Viñuela 《Virology》1984,132(1):160-172
The structure of African swine fever virus particles has been examined by electron microscopy. The analysis of virions prepared by negative staining, thin sectioning, and freeze-drying and shadowing showed that the virus particle was composed of several concentric structures with an overall icosahedral shape. The inner region of the virus particles was a nucleoid that was surrounded by a membrane covered by the capsid. The capsid had side-to-side dimensions of 172 to 191 nm and was built up by capsomers arranged in an hexagonal lattice. Computer-filtered electron micrographs of either negatively stained or freeze-dried and shadowed capsids revealed capsomers with a hexagonal outline and a hole in the center. The intercapsomer distance ranged from 7.4 to 8.1 nm. The triangulation number of the capsid was estimated to be 189 to 217, indicative of 1892 to 2172 capsomers. Extracellular African swine fever virus particles had an external membrane that resembled the cytoplasmic unit membrane. 相似文献
5.
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
6.
Trilla Herrera E Torrecilla Ortíz C Muñoz Seguí J Riera Canals L Suárez Novo JF Marco Pérez LM Franco Miranda E Serrallach Milá N 《Actas urologicas espa?olas》2000,24(5):423-428
First described by the end of the fifties, pelvic lipomatosis is an uncommon disease that develops as a result of an excessive proliferation of benign fat tissue within the perivesical and perirectal spaces. The compressive effect on the urinary, and to a lesser degree, the digestive and vascular structures result in the well-known symptoms. Diagnosis is reached through X-ray studies, primarily computerised tomography. Contribution of four new cases in young males diagnosed through imaging studies as well as biopsies in three of them. Evolution has been varying, with medical control of symptoms in two cases and renal function impairment due to upper obstructive uropathy in the other two. 相似文献
7.
8.
Fernanda Neves de Carvalho Carolina Toniolo Zenatti Danila Cassia Reis Santana Juliana Maria da Silva Juliane Cristina Oliveira dos As Katia Kisielow dos Anjos Jessica Sigari Cassia de Lima Santos Marcelle Guerra Olivia Pereira Barros Tomaz Cochemore Roberto Camargo Narciso Mario Lucio Baptista Filho 《The Brazilian journal of infectious diseases》2018
9.
10.
Indiara Soares Oliveira Leonardo Oliveira Pena Costa Alessandra Narciso Garcia Gisela Cristiane Miyamoto Cristina Maria Nunes Cabral Lucíola da Cunha Menezes Costa 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(4):328-335