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Identification, distribution, and sequence analysis of new insertion elements in Caulobacter crescentus.

Ohta, N; Mullin, D A; Tarleton, J; Ely, B; Newton, A
Tipo: text
Publicado em /01/1990 Português
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We describe two insertion elements isolated from Caulobacter crescentus that are designated IS298 and IS511. These insertion elements were cloned from spontaneous flagellar (fla) gene mutants SC298 and SC511 derived from the wild-type strain CB15 (ATCC 19089), in which they were originally identified as insertions in the flbG operon of the hook gene cluster (N. Ohta, E. Swanson, B. Ely, and A. Newton, J. Bacteriol. 158:897-904, 1984). IS298 and IS511 were each present in C. crescentus CB2 and CB15 in at least four different positions, but neither was present in strain CB13 or in several Caulobacter species examined, including C. vibrioides, C. leidyia, and C. henricii. Nucleotide sequence analysis across the chromosome-insertion element junctions showed that IS298 is located 152 base pairs (bp) upstream from the ATG translation start of the hook protein gene flaK, where it is bounded by a 4-bp direct repeat derived from the site of insertion, and that IS511 is inserted at codon 186 of the flaK coding sequence, where it is also bounded by a 4-bp direct repeat duplicated from the site of insertion. The ilvB102 mutation in strain SC125 was also shown to result from insertion sequence IS511, but no duplication of the genomic sequence was present at the insertion element junctions. IS298 contains an imperfect terminal inverted repeat 16 bp long...

Molecular cloning of Drosophila mus308, a gene involved in DNA cross-link repair with homology to prokaryotic DNA polymerase I genes.

Harris, P V; Mazina, O M; Leonhardt, E A; Case, R B; Boyd, J B; Burtis, K C
Tipo: text
Publicado em /10/1996 Português
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Mutations in the Drosophila mus308 gene confer specific hypersensitivity to DNA-cross-linking agents as a consequence of defects in DNA repair. The mus308 gene is shown here to encode a 229-kDa protein in which the amino-terminal domain contains the seven conserved motifs characteristic of DNA and RNA helicases and the carboxy-terminal domain shares over 55% sequence similarity with the polymerase domains of prokaryotic DNA polymerase I-like enzymes. This is the first reported member of this family of DNA polymerases in a eukaryotic organism, as well as the first example of a single polypeptide with homology to both DNA polymerase and helicase motifs. Identification of a closely related gene in the genome of Caenorhabditis elegans suggests that this novel polypeptide may play an evolutionarily conserved role in the repair of DNA damage in eukaryotic organisms.

Detection of immunoglobulins G and M to rubella virus by time-resolved immunofluorometry.

Shankaran, P; Reichstein, E; Khosravi, M J; Diamandis, E P
Tipo: text
Publicado em /03/1990 Português
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We describe new methods for the detection of immunoglobulin G (IgG) and IgM rubella-specific antibodies in serum. The IgG assay was based on a solid-phase rubella antigen immobilization approach, and the IgM assay was based on the IgM capture assay principle. Both assays used biotinylated antibodies (anti-human IgG and antirubella monoclonal antibody, respectively). The tracer system was based on streptavidin labeled with a fluorescent europium chelate. The final measurements were done by using time-resolved fluorescence. Both assays were thoroughly evaluated with clinical samples and compared successfully with established techniques. We anticipate that these assays are suitable for routine clinical use.

Measurement of inspiratory muscle performance with incremental threshold loading: a comparison of two techniques.

Bardsley, P A; Bentley, S; Hall, H S; Singh, S J; Evans, D H; Morgan, M D
Tipo: text
Publicado em /04/1993 Português
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BACKGROUND--Incremental threshold loading (ITL) is a test of inspiratory muscle performance which is usually performed by breathing through a weighted inspiratory plunger, the load on the inspiratory muscles being increased by externally adding weights to the intake valve. This is not a true threshold device and may be inaccurate. This method was compared with a true threshold device consisting of a solenoid valve which only opens to supply air at a predetermined negative mouth pressure. METHODS--Six naive, normal subjects (three men and three women) aged 22-24 years underwent three tests using each system. The inspiratory loads were increased every minute by equivalent amounts, -10 cm H2O with the solenoid valve and by 50 g with the weighted plunger, until the subjects could not inspire or sustain inspiration for a full minute. Six experienced subjects (four men and two women) aged 23-41 years were subsequently randomised to perform ITL with the solenoid valve, twice with the breathing pattern fixed and twice free. RESULTS--The solenoid valve generated a more accurate mouth pressure response and was less variable at higher loads than the weighted plunger. The work performed (expressed as the pressure-time product) was less with the solenoid valve but was more reproducible. ITL with the solenoid valve was not influenced by controlling the breathing pattern of the subjects. CONCLUSIONS--The solenoid valve has several features that make it superior to the weighted plunger as a device for ITL. It generates a more accurate mouth pressure response which is less variable at higher loads. Increases in load are smoother and quicker to introduce. ITL with the solenoid valve is not influenced by varying breathing patterns and does not require any external regulation.

Eye Disease in the Tropics

Bisley, G. G.
Tipo: text
Publicado em /04/1983 Português
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Inhibition of Na+/H+ Antiport Activity in Sugar Beet Tonoplast by Analogs of Amiloride 1

Blumwald, Eduardo; Cragoe, Edward J.; Poole, Ronald J.
Tipo: text
Publicado em /09/1987 Português
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The effects of amiloride and a series of amiloride analogs have been tested on the Na+/H+ antiport activity in intact vacuoles and tonoplast vesicles isolated from sugar beet cell suspension cultures. There is a competitive interaction between amiloride analogs and sodium. Substitution of one or both H-atoms of the 5-amino group of amiloride (apparent Ki about 150 micromolar) resulted in a 3- to 200-fold increase in inhibitory potency of the antiport activity.

Some anatomical features of the mandible

Gabriel, A. C.
Tipo: text
Publicado em /10/1958 Português
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Should the Unpublished Results of Clinical Trials Be Available to Other Researchers and Physicians?

Lundberg, George D.
Fonte: Medscape Publicador: Medscape
Tipo: text
Publicado em 16/09/2004 Português
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John Maynard Smith: January 6, 1920–April 19, 2004

Charlesworth, Brian
Fonte: Genetics Society of America Publicador: Genetics Society of America
Tipo: text
Publicado em /11/2004 Português
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Medical Litigation

Tipo: text
Publicado em 15/01/1986 Português
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HS-599: a novel long acting opioid analgesic does not induce place-preference in rats

Lattanzi, R; Negri, L; Giannini, E; Schmidhammer, H; Schutz, J; Improta, G
Tipo: text
Publicado em /09/2001 Português
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When administered subcutaneously HS-599, a new didehydroderivative of buprenorphine (18,19-dehydrobuprenorphine), produced a long-lasting antinociceptive response in rats. Its potency exceeded twice that of buprenorphine. In the tail-flick test it acted as a full agonist but in the plantar test only as a partial agonist. Whereas the ?-opioid antagonists naloxone and naltrexone antagonized HS-599 antinociception the ?-opioid antagonist naltrindole and the ?-opioid antagonist nor-binaltorphimine did not.Unlike buprenorphine and morphine, HS-599 never induced conditioned place-preference in rats.In radioligand binding assays, compared with buprenorphine HS-599 had 3 fold higher ?-opioid receptor affinity but lower ?- and ?-opioid receptor affinity.In isolated guinea-pig ileum preparations, HS-599 only partially inhibited the electrically-stimulated contraction, acting as a partial opioid agonist. When tested against the ?-opioid receptor agonist dermorphin, it behaved as a non-equilibrium antagonist. Conversely, in mouse vas deferens (rich in ?-opioid receptors) and rabbit vas deferens preparations (rich in ?-opioid receptors) HS-599 acted as a pure equilibrium antagonist, shifting the log-concentration-response curves of the ?-opioid agonist deltorphin I and the ?-opioid agonist U-69593 to the right.In conclusion...

Letter: Nephrotoxic drugs.

Tune, B M; Kempson, R L
Tipo: text
Publicado em 22/09/1973 Português
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TRAUMATIC THROMBOSIS OF THE UPPER EXTREMITIES*

Swindt, Joseph K.
Tipo: text
Publicado em /11/1927 Português
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Productivity: Getting Cataract Patients ‘Through and Out’

Thulasiraj, RD; Saravanan, S
Fonte: International Centre for Eye Health Publicador: International Centre for Eye Health
Tipo: text
Publicado em //2000 Português
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Dramatic improvement in non-AIDS related progressive multifocal leucoencephalopathy

Aure, K; Behin, A; Louillet, F; Lafitte, C; Sanson, M; Vernant, J
Fonte: BMJ Group Publicador: BMJ Group
Tipo: text
Publicado em /09/2005 Português
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Translation and validation of a Japanese version of the irritable bowel syndrome-quality of life measure (IBS-QOL-J)

Kanazawa, Motoyori; Drossman, Douglas A; Shinozaki, Masae; Sagami, Yasuhiro; Endo, Yuka; Palsson, Olafur S; Hongo, Michio; Whitehead, William E; Fukudo, Shin
Fonte: BioMed Central Publicador: BioMed Central
Tipo: text
Publicado em 03/03/2007 Português
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p53 Mutations in Nasal Natural Killer/T-Cell Lymphoma from Mexico : Association with Large Cell Morphology and Advanced Disease

Quintanilla-Martinez, Leticia; Kremer, Marcus; Keller, Gisela; Nathrath, Michaela; Gamboa-Dominguez, Armando; Meneses, Abelardo; Luna-Contreras, Lourdes; Cabras, Antonello; Hoefler, Heinz; Mohar, Alejandro; Fend, Falko
Fonte: American Society for Investigative Pathology Publicador: American Society for Investigative Pathology
Tipo: text
Publicado em /12/2001 Português
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Nasal NK/T-cell lymphoma is a unique form of lymphoma highly associated with Epstein-Barr virus, and with a characteristic geographic distribution. Recently, we showed that p53 is overexpressed in a high percentage of nasal NK/T-cell lymphomas. The aim of this study was to analyze the status of the p53 gene, and correlate it with the expression of p53 protein and its downstream target, the cyclin-dependent kinase inhibitor p21, in a series of 25 cases of well-characterized nasal NK/T-cell lymphoma from Mexico. The highly conserved exons 5 to 8 of the p53 gene were amplified by polymerase chain reaction and screened for mutations by denaturing high-pressure liquid chromatography. Abnormal polymerase chain reaction products detected by denaturing high-pressure liquid chromatography and additional selected cases were sequenced. In addition, the incidence of loss of heterozygosity at the p53 locus was analyzed in 12 cases. Of the 25 patients, 17 were male and 8 female (M:F ratio, 2.1:1), with a median age of 43 years (range, 21 to 93 years). Morphologically, most of the cases were composed of a mixture of medium-sized cells and large transformed cells (21 cases), and four cases were composed exclusively of large transformed cells. Three different groups determined by p53 gene status and expression of p53 protein were identified: group 1 was p53 +/p53 mutated (five cases...

Thus We Are Men

Tipo: text
Publicado em 26/01/1952 Português
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Friday Afternoon Lectures, 1980-1931

Tipo: text
Publicado em /09/1930 Português
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Studies on Sulfhydryl Groups during Cell Division of Sea Urchin Egg : IV. Contractile properties of the thread model of KCl-soluble protein from the sea urchin egg

Sakai, Hikoichi
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: text
Publicado em 01/01/1962 Português
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A KCl-soluble protein fraction can be extracted from the water-insoluble residue of the homogenate of sea urchin eggs which contains three major components separable by ultracentrifugation. When the extract is stirred in acetone or distilled water, a fibrous precipitate appears which has a strong birefringence positive in the direction of the long axis. When the fraction is squirted through a slender tubing, it precipitates in the form of a thread. The thread model contracts vigorously under the action of di-, tri-, and tetravalent metal ions; the contraction can be reversed by EDTA. The contraction and the elongation of the thread model can be repeated many times. The thread model contracts also in the presence of dehydroascorbic acid, cystine, oxidized glutathione, or other oxidizing agents, and this contraction is reversed by reducing agents such as cysteine or ascorbic acid. When —SH groups of the thread model are blocked by various —SH reagents, the contraction by metal ions is inhibited to some extent. As mechanisms of the contraction, electrostatic forces between metal ions and negative charges of the thread model are essential for metal ion-induced contraction and oxidation of —SH groups of the thread model for the contraction by oxidizing reagents.