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91.
A common gene for juvenile and adult-onset primary open-angle glaucomas confined on chromosome 1q. 总被引:11,自引:2,他引:9 下载免费PDF全文
J Morissette G Ct J L Anctil M Plante M Amyot E Hon G E Trope J Weissenbach V Raymond 《American journal of human genetics》1995,56(6):1431-1442
Primary open-angle glaucoma (POAG), which causes progressive loss of the visual fields, was subdivided into two groups according to age at onset: (1) chronic open-angle glaucoma (COAG) diagnosed after age 40 years and (2) juvenile open-angle glaucoma (JOAG) diagnosed between 3 years of age and early adulthood. A JOAG gene (GLC1A) was recently mapped to chromosome 1q. We studied 142 members of a huge multigenerational French Canadian family affected with autosomal dominant POAG. Either JOAG or COAG was diagnosed in 40 patients. Six subjects were also diagnosed with ocular hypertension (OHT), which may lead to POAG. To localize a common disease gene that might be responsible for both glaucoma subsets, we performed linkage analysis considering JOAG and COAG under the same phenotypic category. JOAG/COAG was tightly linked to seven microsatellite markers on chromosome 1q23-q25; a maximum lod score of 6.62 was obtained with AF-M278ye5. To refine the disease locus, we exploited a recombination mapping strategy based on a unique founder effect. The same characteristic haplotype, composed of 14 markers spanning 12 cM between loci D1S196 and D1S212, was recognized in all persons affected by JOAG, COAG, or OHT, but it did not occur in unaffected spouses and in normal family members > 35 years of age, except for three obligatory carriers. Key recombination events confined the disease region within a 9-cM interval between loci D1S445 and D1S416/D1S480. These observations demonstrate that the GLC1A gene is responsible for both adult-onset and juvenile glaucomas and suggest that the JOAG and COAG categories within this family may be part of a clinical continuum artificially divided at age 40 years. 相似文献
92.
Summary We have investigated features for minimizing the inactivation of tyrosinase (E.C. 1.14.18.1) that is caused by immobilization on glass beads and Celite®. The degree of inactivation is dependent on the enzyme loading and the carrier's surface area. Addition of a sacrificial protein during the immobilization procedure offers a protective effect with increased residual activity on the basis of comparable enzyme loading. 相似文献
93.
Richard L. Schading Raymond I. Carruthers Barbara A. Mullin-Schading 《Biocontrol Science and Technology》1995,5(2):201-208
The viability of conidia from two species of deuteromycetes fungi pathogenic to insects was determined using two fluorochrome stains, fluorescein diacetate (FDA) and propidium iodide (PI). These stains were used either alone or in combination, and results were compared with standard conidial germination tests. FDA fluoresces bright green in viable conidia and PI fluoresces red in non-viable conidia, when viewed using specific fluorescence microscopic techniques. Conidia from two isolates of Paecilomyces fumosoroseus (Wize) Brown and Smith and two isolates of Beauveria bassiana (Balsamo) Vuillemin were evaluated. Conidia were suspended in deionized water and half of each suspension was treated with microwave radiation to kill all the conidia. Conidia were tested for viability in non-microwaved suspensions in a mixture (ca. 1:1) of viable and non-viable conidial suspensions, and in the microwaved suspensions that contained all non-viable conidia. No significant differences were observed for the four isolates tested between germination tests on water and agar and viability tests conducted with FDA alone or FDA in combination with PI. One isolate of B. bassiana that had been damaged in storage was also tested. Differences were observed between the actual germination and the percentage of viability determined using FDA or FDA plus PI. Damaged conidia maintained a measure of viability and fluoresced green, but did not fully germinate. 相似文献
94.
Summary Periplasmic-leaky (lky) Hfr mutant strains of Escherichia coli K12, grown in low-phosphate Tris medium, excreted alkaline phosphatase (AP) into the extracellular fluid. The lky207 mutation, which proved to induce the highest AP excretion rate, was transferred to an F- host, carrying a phoS, T mutation allowing constitutive AP biosynthesis. Use of high-phosphate LB-rich medium for growing this F-
lky strain improved cell biomass, extracellular AP activity and excretion specificity in favour of the enzyme. Physiological studies helped us to develop a new culture medium (LB 8.3) giving higher enzyme and excretion yields. LB 8.3 medium also increased cell viability of lky mutants stored at 4° C.Using optimized culture conditions, the highest extracellular enzyme activity produced by lky mutant 706 was reached in the late stationary growth phase and was equal to 1,400 U/ml of culture medium (i.e., 6 times the intracellular AP content of wild-type strain, Ga15, developed in derepressed conditions); AP released into the extracellular fluid corresponded to 34% of total excreted proteins and was equivalent to a purified enzyme preparation. 相似文献
95.
96.
The H+/O ratio of proton translocation linked to the oxidation of succinate by mitochondria 总被引:1,自引:0,他引:1
Raymond Wootton 《FEBS letters》1984,178(2):187-192
In a recent communication Lehninger and co-workers (Costa, L.E., Reynaferje, B., and Lehninger, A.L. (1984) J. Biol. Chem. 259, 4802-4811) reported values approaching 8 for the H+/O ratio of vectorial proton ejection from rat liver mitochondria respiring with succinate. Here we present a rigorous analysis of these measurements which reveals that they may significantly overestimate the true H+/O stoicheiometry. 相似文献
97.
Diane Willenbrock McNees Roscoe W. Lewis Betty J. Ponzio Raymond F. Sis Frank J. Stein 《Primates; journal of primatology》1984,25(1):103-109
Blood chemistry values were collected over a three-year period from at least 10 colony-born and 24 wild-born apparently normal
common marmosets. BUN, SGOT, creatinine, calcium, phosphorus, alkaline phosphatase, protein, albumin, cholesterol, triglycerides,
uric and glucose values were determined. A statistical comparison of baseline values was made between wild-born, colony-born,
male and female marmosets. Also the same comparison was made between common marmosets and cotton-top tamarins, white lipped
tamarins and human subjects. 相似文献
98.
Dr. Raymond E. Papka 《Cell and tissue research》1978,194(2):219-236
Summary The development of innervation to the atrial myocardium of rabbits from 20th day of gestation to 35 days postnatal was studied ultrastructurally by electron microscopy and by demonstration of catecholamines by histofluorescence. Special attention was directed to the first morphologic appearance of nerve fibers and terminals and the closeness of juxtaposition of terminals with myocardial cells. Adrenergic and cholinergic terminals were identified on the basis of their differential ability to take-up and store the false adrenergic neurotransmitter 5-hydroxydopamine. Adrenergic terminals were first encountered at 20 days of gestation whereas cholinergic terminals could not be positively identified until the 24th day of gestation. Throughout development adrenergic terminals were more numerous than cholinergic, about 71 % of the terminals encountered being adrenergic. Many terminals approach closely (20–30 nm) to the sarcolemma of the muscle cells of the atrium. In many instances adrenergic and cholinergic fibers travel together in the same nerve bundle and are closely apposed without intervening Schwann-cell cytoplasm. Such a relationship could allow peripheral interaction between these fibers in the myocardium.Supported in part by the Kentucky Heart Association, Human Development Studies Program of the University of Kentucky and DHEW Grant 1 RO1 HL 22226-01 HED from the National Heart, Lung and Blood Institute. The technical assistance of Merle Wekstein is appreciated 相似文献
99.
H. L. Raymond 《Entomologia Experimentalis et Applicata》1977,21(2):121-129
Résumé Les performances de pièges à Tabanidae de type Manitoba ont été étudiées en milieu montagnard et subalpin. On a testé les influences respectives de la présence ou de l'absence d'une source de CO2, de la nature de cette source (solide ou gazeuse), de la présence ou de l'absence d'un leurre visuel (sphère noir brillant), de la nature transparente ou opaque de la partie supérieure du piège (hotte conique). Plus de 8.000 Tabanidae et plus de 51.000 Muscidae ont été pris au cours de ces essais totalisant 660 heures-pièges.
Summary Manitoba traps, traps without decoy or with black canopy, unbaited or baited with dry ice or compressed carbon dioxide, were compared for the numbers of horse flies and muscid flies caught in mountainous mixed wood and pasture land and in subalpine larch forest between 1500 m and 2200 m, in July. More muscid flies were captured in the compressed CO2 baited traps than in dry ice baited traps. Haematopota pluvialis, Tabanus maculicornis and Tabanus quatuornotatus were more attracted by CO2 than Tabanus bromius. T. bromius was more attracted by the decoy than other species. The genus Atylotus and T. bromius are more attracted to the black canopy than other species. The visual decoy is more necessary to the efficiency of the trap than the chemical bait. The CO2 baited Manitoba trap caught the greatest number of horse flies (180 per trap and per hour). The unbaited Manitoba trap was efficient too, but other traps were inefficient. About 8000 horse flies and 51000 muscid flies were caught.相似文献
100.
Arni V. Thorsson Raymond L. Hintz 《Biochemical and biophysical research communications》1977,74(4):1566-1573
Somatomedin is a growth hormone-stimulated peptide purified from plasma which has actions on cartilage and other tissues. Specific receptor sites for somatomedin distinct from insulin receptor sites have been described for many tissues. This study demonstrates the existence of a specific 125I-somatomedin receptor site on circulating human mononuclear cells. This will provide an easily accessible human source for the study of changes in somatomedin receptors in disease states. 相似文献