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21.
Seeds of legume species Argyrolobium flaccidum, Desmodium elegans, D. tortuosum, Indigofera gangetica, Lespedeza stenocarpa and Sesbania sesban have been evaluated for the toxicity to rhizobia for the first time. Legume species differ in quantity and quality of released seed toxins to which the symbiotic bacteria respond differentially. Therefore, seed toxicity may be used as a selectable taxonomic marker for the strainal identification of rhizobia. Seed toxins are located in seed coat and are thermolabile to some extent. The seed genotypes, within the species, differ in toxicity and such polymorphism can be used in the selection of toxin-free seeds. Seed surface-disinfection procedures involving subsequent soaking and washing with water are the most useful methods for reducing the seed toxins. The seed toxins from I. gangetica inhibited the growth of its homologous strain but did not affect nodulation and symbiotic parameters. Various seed-toxin-producing legume species did not affect nodulation and symbiotic efficiency and effectiveness. 相似文献
22.
Y Terada H Suma T Saito S Fukuda T Takayama Y Wanibuchi S Furuta 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(11):873-877
The long term (10 to 15 years) results of coronary artery bypass grafting (CABG) were studied in 20 patients. The duration of follow-up was ranged from 130 to 170 months with mean 146.4 months. Ten out of 20 patients underwent coronary angiography (CAG), which disclosed that the late patency of saphenous vein (SV) grafts was 68.8% (11/16), but 54.5% (6/11) of patent SV grafts showed atherosclerotic changes such as irregularity and localized narrowing. On the other hand, internal thoracic artery (ITA) grafts were all patent without any atherosclerotic luminal changes. We recognized that ITA grafts were superior to SV grafts from an angiographic standpoint of view in the long term in Japan. 相似文献
23.
Bharti Razdan Peter J. Marro Outi Tammela Rajiv Goel Om Prakash Mishra Maria Delivoria-Papadopoulos 《Brain research》1993,600(2):308-314
The effect of hypoxia on the structure and function of the synaptosomal membranes and myelin fraction (glial cells, neuronal cell bodies and axonal membranes) was investigated by measuring Na+,K+-ATPase activity and levels of lipid peroxidation products in cerebral cortical synaptosomal membranes and myelin fractions obtained from newborn piglets. Hypoxic hypoxia was induced and cerebral hypoxia was documented as a decrease in the ratio of phosphocreatine to inorganic phosphate (PCr/Oi) using31P-NMR spectroscopy. PCr/Pi decreased from baseline of2.93 ± 0.76to0.61 ± 0.36 during hypoxia. The synaptosomal membrane Na+,K+-ATPase activity decreased from a control value of56.6 ± 3.7to40.4 ± 6.0 μgmol Pi/mg protein/h during hypoxia. The level of conjugated dienes increased from zero (reference value) to4.5 ± 2.7 nmol/mg lipid and the level of fluorescent compounds increased from23.5 ± 2.2to92.6 ± 46.4 ng quinine sulfate/mg lipid in the synaptosomal membranes during hypoxia. No change in myelin fraction Na+,K+-ATPase activity or levels of lipid peroxidation products were noted. These data indicate that sunaptosomal membranes, rich in polyunsaturated fatty acids, are more susceptible to oxygen free radical mediated lipid peroxidative damage during hypoxia. 相似文献
24.
H Suma T Nishimoto M Kawakami H Morita 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1989,37(6):1194-1196
A 57-year-old female underwent coronary artery bypass reoperation successfully by utilizing the free gastroepiploic artery (GEA) graft in combination with the in situ left internal mammary artery (IMA) graft. The left IMA was anastomosed to the left anterior descending artery and the "free" GEA was anastomosed to the left IMA proximally and to the first diagonal branch distally. The patient recovered well with a disappearance of angina. Postoperative angiogram at 6 weeks showed good patency of both grafts and improvement of left ventricular contraction was obtained. Thus, GEA can be utilized not only as an "in situ" graft, but also as a "free" graft, effectively. 相似文献
25.
Karen W. Gripp Lindsey A. Morse Marni Axelrad Kathryn C. Chatfield Aaron Chidekel William Dobyns Daniel Doyle Bronwyn Kerr Angela E. Lin David D. Schwartz Barbara J. Sibbles Dawn Siegel Suma P. Shankar David A. Stevenson Mihir M. Thacker K. Nicole Weaver Sue M. White Katherine A. Rauen 《American journal of medical genetics. Part A》2019,179(9):1725-1744
Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence‐based guidelines due to the lack of data for this rare condition. 相似文献
26.
27.
Summary Spontaneous mitotic intragenic and intergenic recombination at various sites is enhanced 10 to 100 fold in the methyl methanesulfonate (MMS)-sensitive mutants mms9-1, mms13-1, and mms21-1 of Saccharomyces cerevisiae. All three mutants show elevated rates of spontaneous mutation. Sporulation is reduced in diploids homozygous for any of the three mutations, and a deficiency in meiotic recombination and meiotic chromosome segregation is observed. Pleiotropic effects on cell viability, growth rate, and radiation sensitivity, in combination with the alterations in recombination and mutagenesis displayed by mutant strains, suggest that the MMS9, MMS13, and MMS21 genes play important roles in DNA replication and/or genetic recombination. 相似文献
28.
Siddharth K. Prakash Soniely Lugo‐Ruiz Michelle Rivera‐Dávila Nunilo Rubio Jr. Avni N. Shah Rebecca C. Knickmeyer Cindy Scurlock Melissa Crenshaw Shanlee M. Davis Gary A. Lorigan Aaron T. Dorfman Karen Rubin Cheryl Maslen Vaneeta Bamba Paul Kruszka Michael Silberbach Scientific Advisory Board of the TSRR 《American journal of medical genetics. Part C, Seminars in medical genetics》2019,181(1):7-12
To address knowledge gaps about Turner syndrome (TS) associated disease mechanisms, the Turner Syndrome Society of the United States created the Turner Syndrome Research Registry (TSRR), a patient‐powered registry for girls and women with TS. More than 600 participants, parents or guardians completed a 33‐item foundational survey that included questions about demographics, medical conditions, psychological conditions, sexuality, hormonal therapy, patient and provider knowledge about TS, and patient satisfaction. The TSRR platform is engineered to allow individuals living with rare conditions and investigators to work side‐by‐side. The purpose of this article is to introduce the concept, architecture, and currently available content of the TSRR, in anticipation of inviting proposals to utilize registry resources. 相似文献
29.
Sertoli-Leydig cell tumors are uncommon tumors of ovary accounting for about 1% of sex cord stromal tumors. They constitute between 0.1% to 0.5% of all the primary ovarian neoplasms. The majority of reported cases are moderately or poorly differentiated combined Sertoli-Leydig cell tumors. A rare case of Sertoli-Leydig cell tumor with heterologous element in a 14 year girl is described. The heterologous component comprised smooth muscle, an uncommon element, that was seen in 60 to 70% of the tumor area. The epithelial element of the tumor consisted of solid, tubular and foci of retiform pattern. Both these features imply a poor prognosis. 相似文献
30.
A simple and highly sensitive enzymeimmunoassay (EIA) for GH determination in buffalo plasma on microtitreplates using biotin-streptavidin amplification system and the second antibody coating was developed. Biotin was coupled to GH and used to bridge between streptavidin-peroxidase and immobilized antiserum in competitive assay. The EIA was carried out directly in 100 microL buffalo plasma. The GH standards ranging from 0.05 ng/well/100 microL to 12.8 ng/well/100 microL were prepared in hormone free plasma collected from an aged (> 15 years) senile buffalo. The sensitivity of the EIA procedure was 50 pg/well GH. which corresponded to 0.50 ng/mL plasma; the 50% relative binding sensitivity was seen at 800 pg/well/100 microL. Plasma volumes for the EIA, viz., 25, 50, and 100 microL did not influence the shape of standard curve, even though a slight drop in the OD450 was seen with higher plasma volumes. For the biological validation of the assay, 12 Murrah buffalo calves were used. Six of these were administered synthetic bovine growth hormone-releasing factor (10 microg/100 kg body weight, i.v., and the remaining six animals were administered sterile normal saline and kept as controls. Jugular blood samples were collected at -60, -45, -30, -15, -10, -5, 5, 10, 15, and 30 min and, thereafter, at an interval of 15 min using an indwelling jugular catheter, beginning 1 h prior to GRF injection up to 8 h post treatment. In all animals, a peak of GH was recorded within 5 to 20 min of GRF administration, which confirms the biological validation of the EIA. To confirm homogeneity of buffalo GH with bovine GH, a parallelism test was conducted between the buffer standard curve of bovine GH and GH measured from serial dilution of buffalo plasma containing a high level of endogenous growth hormone. 相似文献