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641.
Klein H 《Science (New York, N.Y.)》1947,105(2714):4-5
642.
CASE REPORT AND CLINICAL REVIEW: Unilateral facial myokymia in a dog with an intracranial meningioma
A 23-month-old castrated male Cavalier King Charles spaniel was evaluated because of a 6-month history of unusual rippling/undulating movements of the right facial muscles that were continuous and persisted during sleep. Neurological examination revealed narrowing of the right palpebral fissure and unilateral right-sided facial myokymia that was characterised by myokymic, and to a lesser degree, neuromyotonic discharges on concentric needle electromyographic examination. After persisting unchanged for almost 2.5 years from its onset, the facial myokymia gradually disappeared over a 6-month period concomitant with the emergence of a persistent ipsilateral facial paralysis and head tilt. At 5 years and 9 months after the first examination, signs of ipsilateral lacrimal, pharyngeal and laryngeal dysfunction became evident and the dog was euthanased. Postmortem examination identified a malignant (WHO grade III) meningioma in the right cerebellopontomedullary angle that compressed the ventrolateral cranial medulla, effaced the jugular foramen and internal acoustic meatus and extended into the facial canal of the petrous temporal bone. Novel findings were the unique observation of isolated unilateral facial myokymia preceding diagnosis of a meningioma affecting facial nerve function within the caudal cranial fossa and the remarkably long duration of neurological signs (75 months) attributable to the neoplasm. 相似文献
643.
The production of interspecific or intergeneric progeny involving Sorghum spp. is greatly enhanced by the presence of the iap (Inhibition of Alien Pollen) allele in sorghum [Sorghum bicolor (L.) Moench]. Variation in the expressivity of the iap phenotype has been observed in previous studies, leading to the hypothesis that the humidity during pollination is affecting the degree of alien pollen adhesion and pollen tube growth. The objective of this study was to determine the optimum humidity for maximum maize pollen tube growth on sorghum florets homozygous for iap. Growth chambers were used to create environments of 45, 65, and 85 % humidity with reciprocal crosses made between the 65 and 85 % humidity chambers. Maize pollen was dusted onto the stigmas of Tx3361 (iap iap) and ATx623 (Iap Iap). Pollen adhesion and germination were higher for pollinations with Tx3361 at all humidity levels but the greatest adhesion and germination was observed at 45 % humidity for Tx3361. Under this humidity, pollen tube growth to the style and ovary was observed. The results indicate that lower humidity maximizes maize pollen adhesion and germination on the stigmas of Tx3361. Analysis of the differences in adhesion between Tx3361 and ATx623 indicate that Iap affects pollen adhesion at the stigma surface and may be controlling pollen–pistil incompatibility in interspecific crosses in sorghum. 相似文献
644.
André Luis da Cruz Hugo Ribeiro da Silva Lícia Maria Lundstedt Arno Rudi Schwantes Gilberto Moraes Wilfried Klein Marisa Narciso Fernandes 《Fish physiology and biochemistry》2013,39(2):243-256
Hypoxic water and episodic air exposure are potentially life-threatening conditions that fish in tropical regions can face during the dry season. This study investigated the air-breathing behavior, oxygen consumption, and respiratory responses of the air-breathing (AB) armored catfish Pterygoplichthys anisitsi. The hematological parameters and oxygen-binding characteristics of whole blood and stripped hemoglobin and the intermediate metabolism of selected tissue in normoxia, different hypoxic conditions, and after air exposure were also examined. In normoxia, this species exhibited high activity at night and AB behavior (2–5 AB h?1). The exposure to acute severe hypoxia elicited the AB behavior (4 AB h?1) during the day. Under progressive hypoxia without access to the water surface, the fish were oxyregulators with a critical O2 tension, calculated as the inspired water O2 pressure, as 47 ± 2 mmHg. At water O2 tensions lower than 40 mmHg, the fish exhibited continuous apnea behavior. The blood exhibited high capacity for transporting O2, having a cathodic hemoglobin component with a high Hb–O2 affinity. Under severe hypoxia, the fish used anaerobic metabolism to maintain metabolic rate. Air exposure revealed physiological and biochemical traits similar to those observed under normoxic conditions. 相似文献
645.
S. Fischer J. Möhring C. C. Schön H.‐P. Piepho D. Klein W. Schipprack H. F. Utz A. E. Melchinger J. C. Reif 《Plant Breeding》2008,127(5):446-451
The ratio of variance due to specific vs. general combining ability (GCA) (σ2SCA:σ2GCA) is of central importance for predicting hybrid performance from GCA effects. The objectives of our study were to (1) analyse the changes in estimates of σ2GCA, σ2SCA and their ratio during 30 years of hybrid maize breeding and (2) compare the observed trends in genetic variances with those expected under a simple genetic model. We analysed multilocation yield trials based on the North Carolina Design II conducted in the maize breeding programme of the University of Hohenheim from 1975 to 2004 for grain yield (GY) and dry matter content (DMC). GY showed a significant (P < 0.05) annual increase of 0.17 Mg/ha, but no linear trend was found for DMC. Since the beginning of hybrid breeding at the University of Hohenheim, the sum of estimates of σ2GCA of the flint and dent heterotic groups were higher than the estimates of their σ2SCA. This predominance did not change with ongoing inter‐population improvement. Consequently, superior hybrids can be identified and selected mainly based on their prediction from GCA effects. 相似文献
646.
Nikhil Y. Patil N. Ace Pugh Robert R. Klein Hector S. Martinez Raul S. Martinez Raul Rodriguez-Herrera 《Journal of Crop Improvement》2019,33(1):1-24
Breeding efforts in cereal crops directed toward developing or improving end-use products of grain require assessment of existing phenotypic variance and an understanding of the genetic control of grain quality traits. To this end, a grain sorghum [Sorghum bicolor (L.) Moench] mapping population consisting of 113 F2:7 recombinant inbred lines (RILs) derived from a cross between Sureño and RTx430 was evaluated in multiple environments for grain composition (fat, fiber, protein, starch) using near-infrared reflectance spectroscopy (NIRS), and size estimates of grain parts (embryo, vitreous endosperm, floury endosperm, kernel area) using an image-based phenotyping software system. Estimates of broad-sense heritability of grain compositional traits ranged from 0.11 to 0.90, whereas those of grain size ranged from 0.16 to 0.72. Composite interval mapping (CIM) was applied to a single nucleotide polymorphism (SNP)-based linkage map to identify marker-trait associations, and through these efforts, a total of 37 quantitative trait loci (QTL) for grain quality were identified across environments. Each QTL explained between 7 and 23% of the phenotypic variation for a given grain trait. Three of the five QTL that colocalized were for traits with significant negative correlation, which included grain protein content that was negatively correlated with grain starch content. In addition, several traits that were positively correlated (e.g. fat and fiber content) also revealed colocalized QTL. Finally, we compared the present study with previous studies identifying grain composition trait loci in an effort to identify genomic regions controlling grain traits across a diversity of environments and sorghum genotypes. 相似文献
647.
Alternating Rabacfosadine/Doxorubicin: Efficacy and Tolerability in Naïve Canine Multicentric Lymphoma
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648.
Feline ocular melanomas show a high malignant behaviour, but adjunctive therapies are non‐existent. The aim of this pilot study was to determine, whether feline ocular melanomas harbour mutations comparable to mutations in human melanomas and to evaluate the gene expression status of genes known to be involved in initiation and progression of human melanomas. Mutation hotspot regions of several genes of feline ocular melanomas were analysed by DNA sequencing and RNA expression levels of the respective genes and others were evaluated by quantitative real‐time polymerase chain reaction (RT‐qPCR). Common mutations found in human melanomas are not present in feline tumours. Gene expression analysis revealed a significant upregulation of KIT and LTA4H, as well as a downregulation of GNAQ, GNA11, BRAF and RASSF1 in feline ocular melanomas. As KIT seems to harbour a potential as target gene in human uveal melanomas, future studies should further investigate the potential of KIT as target for adjunctive therapy in feline ocular melanomas. 相似文献
649.
Sylvie Oddou-Muratorio Aurore Bontemps Etienne K. Klein Igor Chybicki Giovanni G. Vendramin Yoshihisa Suyama 《Forest Ecology and Management》2010
The comparison between estimates of historical gene flow, using variance in allelic frequencies, and estimates of contemporary gene flow, using parentage assignment, is expected to provide insights into ecological and evolutionary processes at work within and among populations. Genetic variation at microsatellite loci was used to quantify genetic structure in two wind pollinated, gravity and animal-dispersed tree species (Fagus sylvatica L. and Fagus crenata Blum.) and to derive historical estimates of gene flow. The gene dispersal distances estimated assuming effective population density to be 1/4 of the observed density were ∼77 m in European beech and ∼40 m in Japanese beech. Parentage analyses and a neighbourhood model approach were used to estimate contemporary patterns of seed and pollen dispersal. Our results suggest restricted seed dispersal abilities in both European beech (δs = 10.5 m) and Japanese beech (δs = 12.4 m), with an exponential shaped seed dispersal kernel. A non-negligible rate of seed immigration (ms = 27%) was detected in European beech sites but not in Japanese beech site. Pollen dispersal within studied sites also appeared limited (δp = 41.63 m in European beech and δp = 79.4 m in Japanese beech), despite high rate of pollen immigration (mp = 68% in European beech and mp = 40% m in Japanese beech). Interestingly, contemporary and historical estimates of gene flow were within the same order of magnitude (a few tens of meters). 相似文献
650.
Klein RG 《Science (New York, N.Y.)》2003,299(5612):1525-1527