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1.
Kelsey A. Johnson James Sutherland-Smith Trisha J. Oura Amy F. Sato Bruce Barton 《Veterinary radiology & ultrasound》2023,64(1):86-94
Evaluation of brain disease in veterinary patients uses a wide variety of MRI sequences. A shortened protocol that maintains consistency of interpretation would reduce radiologist reporting time, patient anesthetic time, and client cost. The aims of this retrospective, methods comparison, observer agreement study were to evaluate whether abbreviated MRI protocols alter differential diagnoses and recommendations compared to our institution's standard protocol; evaluate interobserver agreement on standard brain MRIs; and assess whether differential diagnoses change after postcontrast images. Normal and pathologic canine and feline brain MRIs were retrieved from hospital archives. Three protocols were created from each: a 5-sequence noncontrast enhanced Fast Brain Protocol 1 (FBP1); a 6-sequence contrast-enhanced Fast Brain Protocol 2 (FBP2); and an 11-sequence standard brain protocol (SBP). Three blinded veterinary radiologists interpreted FBP images for 98 cases (1 reader/case) and SBP images for 20 cases (3 readers/case). A fourth observer compared these interpretations to the original MRI reports (OMR). Overall agreement between FBPs and OMR was good (k = 0.75) and comparable to interobserver agreement for multiple reviews of SBP cases. Postcontrast images substantially altered conclusions in 17/97 cases (17.5%), as well as improved interobserver agreement compared to noncontrast studies. The conclusions reached with shortened brain protocols were comparable to those of a full brain study. The findings supported the use of a 6-sequence brain MRI protocol (sagittal T2-weighted [T2w] TSE; transverse T2w turbo spin echo fluid-attenuated inversion recovery, T2*-weighted gradient recalled echo, T1-weighted spin echo, and diffusion weighted imaging/apparent diffusion coefficient; and postcontrast transverse T1-weighted spin echo) for dogs and cats with suspected intracranial disease. 相似文献
2.
Takayuki Anzai Masamichi Kaminishi Keizo Sato Laura Kaufman Hijiri Iwata Dai Nakae 《Journal of toxicologic pathology》2015,28(2):57-64
The Standard for the Exchange of Nonclinical Data (SEND), adopted by the US FDA, is part of a set of regulations and guidances requiring the submission of standardized electronic study data for nonclinical and clinical data submissions. SEND is the nonclinical implementation of SDTM (Study Data Tabulation Model), the standard electronic format for clinical regulatory submissions to FDA. SEND, SDTM, and the associated Controlled Terminology have been developed by CDISC (Clinical Data Interchange Standards Consortium). In order to successfully implement SEND, interdisciplinary contributions between sponsors and CROs, need a model for task allocation. This is being undertaken by the Pharmaceutical Users Software Exchange (PhUSE). Because SEND is currently the preferred submission format of the US FDA only and will become required by it starting in December 2016, only American academic societies and companies are actively involved. An exception to this is the INHAND initiative, which leads the way in standardizing terminology for toxicological pathology. On the other hand, international globalization of other clinical and nonclinical practices is not feasible because there are substantial differences between the US and non-US countries in CRO involvement in drug development. Thus, non-US countries must consider and develop approaches to SEND that meet their needs. This paper summarizes the activities of the major organizations involved in SEND development and implementation, discusses the effective use of SEND, and details a compliance scheme (research material of the Showa University School of Medicine) illustrating how pharmaceutical companies can complete a large amount of work up to an FDA application with the effective utilization of CROs and solution providers. 相似文献
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Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed. 相似文献
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Zhengjun Xia Hiroko Sato Satoshi Watanabe Shiji Kawasaki Kyuya Harada 《Euphytica》2005,141(1-2):129-137
We have constructed a soybean (Glycine max (L.) Merrill) bacterial artificial chromosome (BAC) library from green leaf protoplasts of the cultivar, Misuzudaizu. The library contains 53,760 clones with an average insert size of 116 kb. About 2.9% chloroplast DNA origin was revealed by PCR and colony hybridization. Apart from 2.8% clones having no insert, this library represents 5.2 genome equivalents. With this genome coverage, the probability of having any DNA sequence represented in the library is higher than 99.5%. Three-dimensional pools of the BAC library in combination with the use of a high efficiency genome scanning (HEGS) electrophoresis facilitate rapid and efficient PCR-based screening. An average of five positive clones were identified after screening the BAC library with SSR and STS markers. BAC-end walking was performed for three SSR associated BACs. This library will provide a good resource for positional cloning of agronomically and biologically important QTL genes that Misuzudaizu possesses. 相似文献
8.
Deep-seeding tolerance, the emergence of seedlings from deep seeded conditions, is involved in stand establishment in semi-arid
regions, where the soil surface is too dry for seed germination. Genes determining deep-seeding tolerance in barley were mapped
using two doubled haploid populations derived from the following crosses: Harrington × TR306 (H/T)and Step toe × Morex (S/M).
Significant quantitative trait loci (QTLs) for deep-seeding tolerance were found in each population. Two QTL sex plained 40%
of the phenotypic variation in the H/T population and one QTL (S/M) 8% of the total phenotypic variance. Multiple QTLs accounting
for coleoptile length and first internode length were detected in both populations. In the H/T population, there were coincident
QTLs for deep-seeding tolerance, coleoptile length and first internode length on the long arm of chromosome 5H. These QTLs
correspond with previously reported QTLs for abscisic acid and gibberellic acid response. QTL coincidence may be due to the
pleiotropic effects of alleles at a single locus. This information may be useful for breeding programs manipulating morphological
and physiological traits in order to develop varieties for semi-arid regions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
Effectivness of the hybrid-weakness caused by a complementary interaction of two dominant genes Hwc1 and Hwc2 to suppress the spread of the red-grain gene into ordinary white-grained rice cultivars was investigated using the Monte Carlo computer simulation method. It was shown that the weakness genes, as far as being capable of reducing the fitness of the carrier by 80 percent or more, work quite effectively to suppress the genetic contamination of white-grained cultivars due to inflow of pollen from red-grained cultivars due to inflow of pollen from red-grain gene once the gene has been incorporated in to the population in the form of red-grained progeny produced as a result of the imperfect lethality of the initial hybrid between red-and white-grained cultivars. The weakness genes have little or no effect cultivars. The weakness genes have little or no effect either, when the contamination is initiated by an inflow of seeds or seedlings from ed-grained cultivars in these situations, removal (selection)of red grained plants Is the only countermeasure to exterminate the red-grain gene. The removal of red grained plants need not be intensive if carried out continuously. The spread of the red-grain gene after initial contamination is suppressed if the red-grain gene and weakness genes are linked. The suppressing effect of the linkage, however, is not substantial when the outcrossing rate is around or smaller than 0.01 as can be assumed in most rice cultivars. 相似文献
10.
Jie Liu Rumi Fujita Michiko Sato Kuniyoshi Shimizu Fumiko Konishi Kiyoshi Noda Shoichiro Kumamoto Chie Ueda Hisatoshi Tajiri Shuhei Kaneko Yoshitaro Suimi Ryuichiro Kondo 《Journal of Wood Science》2005,51(2):189-192
The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5-reductase inhibitory activity among the extracts tested. 相似文献