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941.
942.
Peter Aaby Jette Bukh Ida Maria Lisse Maria Clotilde da Silva 《BMJ (Clinical research ed.)》1988,296(6631):1225-1228
The mortality from measles was studied in an urban area of Guinea-Bissau one year before and five years after the introduction of a vaccination programme. The years after the introduction of immunisation saw a decline in mortality among unvaccinated children with measles. This decline occurred despite a lower age at infection and an increasing prevalence of malnourished children. State of nutrition (weight for age) did not affect the outcome of measles infection. The incidence of isolated cases, however, increased in the period after the introduction of measles vaccination. As mortality was lower among these cases, diminished clustering explained some of the reduction in mortality. Comparison between the urban district and a rural area inhabited by the same ethnic group showed a lower age at infection, less clustering of cases, and lower case fatality ratios in the urban area.Endemic transmission of measles in urban districts leads to less clustering of cases, which may help explain the usually lower case fatality ratios in these areas. As measles vaccination increases herd immunity and diminishes clustering of cases, it may reduce mortality even among unvaccinated children who contract the disease. 相似文献
943.
L R Chen C J Yuan G Somasekhar P Wejksnora J E Peterson A M Myers L Graves P T Cohen E F da Cruz e Silva D J Graves 《Biochemical and biophysical research communications》1989,161(2):746-753
A cDNA encoding the entire tau subunit of rabbit skeletal muscle phosphorylase kinase was reconstructed and inserted into a plasmid containing the Escherichia coli ptac promoter and a constructed plasmid containing the ptac promoter and bacterial chloramphenicol acetyl transferase (CAT) gene, respectively. A significant phosphorylase kinase activity was found, in the first case. In the second case, a fused protein containing 73 amino acids from the CAT protein was obtained. After renaturation, the CAT-tau subunit protein shows enzymatic activity similar to the HPLC-purified and renatured tau subunit. 相似文献
944.
Zhen Ma Yiqun Cao M. Fátima C. Guedes da Silva João J.R. Fraústo da Silva 《Journal of inorganic biochemistry》2010,104(7):704-711
Reactions between 4′-phenyl-terpyridine (L) and several Zn(II) salts (sulfate, nitrate, chloride or acetate) led to the formation of the complexes [Zn2(μ-O2SO2)2L2(CH3OH)2] (1), [Zn(NO3)L(H2O)]NO3 (2), [Zn(Cl)2L] (3) and [Zn(CH3COO)2L] (4) which were characterized by IR, 1H NMR and fluorescence spectroscopies, elemental analysis and single crystal X-ray diffraction. In the dinuclear molecule of 1 the Zn atom is hexacoordinated, with a N3O3 coordination environment and forms an octagonal ZnOSOZnOSO metallacycle. In the remaining structures, the metal atom is envisaged as possessing highly distorted N3X2 (X = O or Cl) square pyramid coordination geometries. The structure of 3 presents two different packing patterns which lead to distinct π-π stackings. In both structures 2 and 4, strong intermolecular hydrogen bonds were identified. The complexes exhibit promising in vitro tumor-inhibiting activities, which are higher than that of cisplatin, against the following human tumor cell lines: promyelocyticfina leukaemia (HL-60), hepatocellular carcinoma (Bel-7402), gastric carcinoma (BGC-823) and nasopharyngeal carcinoma (KB). 相似文献
945.
CA Kalva-Filho EZ Campos VL Andrade ASR Silva AM Zagatto MCS Lima M Papoti 《Biology of sport / Institute of Sport》2015,32(4):333-337
The aims of the present study were to investigate the relationship of aerobic and anaerobic parameters with 400 m performance, and establish which variable better explains long distance performance in swimming. Twenty-two swimmers (19.1±1.5 years, height 173.9±10.0 cm, body mass 71.2±10.2 kg; 76.6±5.3% of 400 m world record) underwent a lactate minimum test to determine lactate minimum speed (LMS) (i.e., aerobic capacity index). Moreover, the swimmers performed a 400 m maximal effort to determine mean speed (S400m), peak oxygen uptake () and total anaerobic contribution (CANA). The CANA was assumed as the sum of alactic and lactic contributions. Physiological parameters of 400 m were determined using the backward extrapolation technique ( and alactic contributions of CANA) and blood lactate concentration analysis (lactic anaerobic contributions of CANA). The Pearson correlation test and backward multiple regression analysis were used to verify the possible correlations between the physiological indices (predictor factors) and S400m (independent variable) (p < 0.05). Values are presented as mean ± standard deviation. Significant correlations were observed between S400m (1.4±0.1 m·s-1) and LMS (1.3±0.1 m·s-1; r = 0.80), (4.5±3.9 L·min-1; r = 0.72) and CANA (4.7±1.5 L·O2; r= 0.44). The best model constructed using multiple regression analysis demonstrated that LMS and explained 85% of the 400 m performance variance. When backward multiple regression analysis was performed, CANA lost significance. Thus, the results demonstrated that both aerobic parameters (capacity and power) can be used to predict 400 m swimming performance. 相似文献
946.
da Silva AJ Coelho AL Simas AB Moraes RA Pinheiro DA Fernandes FF Arruda EZ Costa PR Melo PA 《Bioorganic & medicinal chemistry letters》2004,14(2):431-435
Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group. 相似文献
947.
948.
Tatiane A. Paixão Marcelo C. C. Malta Semíramis A. Soave Herlandes P. Tinoco Maria E.L.T. Costa Angela T. Pessanha Rodrigo O.S. Silva Fernanda M. Coura Luciana F. Costa Andreia P. Turchetti Francisco C.F. Lobato Marilia M. Melo Marcos B. Heinemann Renato L. Santos 《Journal of medical primatology》2014,43(2):118-121
949.
Ribeiro-dos-Santos  Khayat AS Silva A Alencar DO Lobato J Luz L Pinheiro DG Varuzza L Assumpção M Assumpção P Santos S Zanette DL Silva WA Burbano R Darnet S 《PloS one》2010,5(10):e13205
Background
While microRNAs (miRNAs) play important roles in tissue differentiation and in maintaining basal physiology, little is known about the miRNA expression levels in stomach tissue. Alterations in the miRNA profile can lead to cell deregulation, which can induce neoplasia.Methodology/Principal Findings
A small RNA library of stomach tissue was sequenced using high-throughput SOLiD sequencing technology. We obtained 261,274 quality reads with perfect matches to the human miRnome, and 42% of known miRNAs were identified. Digital Gene Expression profiling (DGE) was performed based on read abundance and showed that fifteen miRNAs were highly expressed in gastric tissue. Subsequently, the expression of these miRNAs was validated in 10 healthy individuals by RT-PCR showed a significant correlation of 83.97% (P<0.05). Six miRNAs showed a low variable pattern of expression (miR-29b, miR-29c, miR-19b, miR-31, miR-148a, miR-451) and could be considered part of the expression pattern of the healthy gastric tissue.Conclusions/Significance
This study aimed to validate normal miRNA profiles of human gastric tissue to establish a reference profile for healthy individuals. Determining the regulatory processes acting in the stomach will be important in the fight against gastric cancer, which is the second-leading cause of cancer mortality worldwide. 相似文献950.
Ines Pires da Silva Isabella C. Glitza Lauren E. Haydu Romany Johnpulle Patricia D. Banks George D. Grass Simone M. A. Goldinger Jessica L. Smith Ashlyn S. Everett Peter Koelblinger Rachel Roberts‐Thomson Michael Millward Victoria G. Atkinson Alexander Guminski Rony Kapoor Robert M. Conry Matteo S. Carlino Wei Wang Mark J. Shackleton Zeynep Eroglu Serigne Lo Angela M. Hong Georgina V. Long Douglas B. Johnson Alexander M. Menzies 《Pigment cell & melanoma research》2019,32(4):553-563