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41.
Masanori Hosokawa Ryuichi Kasai Keiichi Higuchi Shuji Takeshita Katsuji Shimizu Hajime Hamamoto Atsuko Honma Mika Irino Kayoko Toda Atsuko Matsumura Mutsumi Matsushita Toshio Takeda 《Mechanisms of ageing and development》1984,26(1):91-102
For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in 相似文献
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Analysis of the floral transcriptome uncovers new regulators of organ determination and gene families related to flower organ differentiation in Gerbera hybrida (Asteraceae)
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Laitinen RA Immanen J Auvinen P Rudd S Alatalo E Paulin L Ainasoja M Kotilainen M Koskela S Teeri TH Elomaa P 《Genome research》2005,15(4):475-486
Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis. 相似文献
44.
Riitta Hari Ritva Hänninen Timo Mäkinen Veikko Jousmäki Nina Forss Mika Seppä Oili Salonen 《Neuroscience letters》1998,240(3):998-134
We describe patient E.P. who occasionally perceives a ‘ghost' hand which copies the previous positions of the left hand with a 0.5–1 min time lag, but follows the movement patterns of the right hand. The symptoms started after an operation of a ruptured aneurysm, followed by an infarction of the right frontal lobe; E.P. also has a previously lesioned corpus callosum. Neuromagnetic recordings revealed that activity of the left secondary somatosensory cortex was strongly suppressed during the ghost arm percept, thereby providing an objective correlate for E.P.'s sensations. We conclude that simultaneous mental contents about body scheme may be based on neural information extracted at considerably different times, resulting in fragmentation of bodily awareness. 相似文献
45.
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OBJECTIVE: Although an association between stressful life events and health problems has been demonstrated, the underlying mechanisms have remained unclear. We examined whether psychological problems and health-risk behaviors underpin the health effects of different event categories. METHOD: The initially healthy participants were 2991 (796 men, 2195 women) municipal employees who had taken no sick leave in 1995. In 1997, they completed a questionnaire requesting information on recent life events and psychological and behavioral factors. The outcome was recorded sickness absences in 1998. RESULTS: In men, the death or serious illness of a family member, violence, and financial difficulties increased the risk of later sickness absence. According to structural equation modeling, violence and financial difficulties also induced psychological problems such as anxiety, mental distress, and lowered sense of coherence. Psychological problems were associated with heightened cigarette and alcohol consumption, which in turn increased sickness absence. A corresponding structural model did not fit the data in relation to death or serious illness of a family member. In women, life events were associated with psychological problems and smoking but not sickness absence. CONCLUSIONS: Longitudinal evidence suggests that increased psychological problems and behaviors involving risk to health partially mediate the effect of stressful life events on health, as indicated by sickness absence. This model received support among men and for the event categories of violence and financial difficulties. Women were less affected by stressful life events than men. 相似文献
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48.
Motonobu Nishimura MD Takashi Nishimura MD Masayuki Ishikawa MD Ayumu Masuoka MD Nobuyuki Okamura MD Keiko Abe MD Takahiro Matsuoka MD Mika Iwazaki MD Kazuhito Imanaka MD Haruhiko Asano MD Shunei Kyo MD 《Journal of artificial organs》2006,9(4):209-213
The presence of a significant organ dysfunction does not immediately exclude patients from consideration for treatment with
a left ventricular assist system (LVAS). However, in treating morbid circulatory shock patients with multiple organ failure,
it is important to know the preoperative and postoperative factor or factors related to the recovery of the damaged organ
function. In this study, we retrospectively analyzed patients receiving a LVAS at our institution and tried to determine the
important factors related to the survival of patients with multisystem failure. Twenty-seven patients who underwent LVAS placement
at Saitama Medical School Hospital between 1993 and 2003 were included in this study. The preoperative risk factors analyzed
were renal dysfunction, respiratory dysfunction, hepatic dysfunction, the existence of active infection, and the combination
of all four factors. As a postoperative factor, the pump flow index (mean LVAS pump flow during the first 2 weeks after LVAS
surgery divided by the body surface area) was analyzed. None of the analyzed preoperative factors could predict survival after
LVAS surgery, but a pump flow index of less than 2.5 l/min/m2 had a significant relationship with death after LVAS surgery. Further analysis revealed that all the patients with a pump
flow index of 3.0 l/min/m2 or more could overcome preoperative organ dysfunction. Congestive heart failure patients with multisystem failure need luxury
pump flow for successful LVAS surgery; this factor could be especially important in device selection and postoperative management. 相似文献
49.
Junko Ueshima Ryo Momosaki Akio Shimizu Keiko Motokawa Mika Sonoi Yuka Shirai Chiharu Uno Yoji Kokura Midori Shimizu Ai Nishiyama Daisuke Moriyama Kaori Yamamoto Kotomi Sakai 《Nutrients》2021,13(3)
Malnutrition negatively affects the quality of life of patients with dysphagia. Despite the need for nutritional status assessment in patients with dysphagia, standard, effective nutritional assessments are not yet available, and the identification of optimal nutritional assessment items for patients with dysphagia is inadequate. We conducted a scoping review of the use of nutritional assessment items in adult patients with oropharyngeal and esophageal dysphagia. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched to identify articles published in English within the last 30 years. Twenty-two studies met the inclusion criteria. Seven nutritional assessment categories were identified: body mass index (BMI), nutritional screening tool, anthropometric measurements, body composition, dietary assessment, blood biomarkers, and other. BMI and albumin were more commonly assessed in adults. The Global Leadership Initiative on Malnutrition (GLIM), defining new diagnostic criteria for malnutrition, includes the categories of BMI, nutritional screening tool, anthropometric measurements, body composition, and dietary assessment as its required components, but not the blood biomarkers and the “other” categories. We recommend assessing nutritional status, including GLIM criteria, in adult patients with dysphagia. This would standardize nutritional assessments in patients with dysphagia and allow future global comparisons of the prevalence and outcomes of malnutrition, as well as of appropriate interventions. 相似文献
50.
Adriana Mika Lukasz P Halinski Tomasz Sledzinski Sylwia Malgorzewicz Paulina Woloszyk Jolanta Dardzinska Alicja Debska-Slizien Michal Chmielewski 《Nutrients》2021,13(3)
Patients with end-stage kidney disease, treated with renal transplantation, are at increased risk of cardio-vascular disease (CVD) and cardio-vascular mortality. They are also characterized by an atherogenic dyslipidemia. Alterations of the fatty acids (FA) profile contribute to increased cardio-vascular risk in the general population. In the current study we test the hypothesis that kidney transplantation is associated with ab-normalities in FA profile. FA profile was analysed by gas chromatography–mass spectrometry in 198 renal transplant recipients, and 48 control subjects. The most profound differences between renal transplant patients and controls were related to the content of branched chain FA, monounsaturated FA, and n-6 polyunsaturated FA, respectively. The FA profile significantly separated the patients from the controls in the principal component analysis (PCA). The abnormalities of FA profile showed a tendency for normalization in long-term kidney recipients, as compared to patients with recent transplants. The n-3 PUFA content demonstrated a strong inverse association with the presence of inflammation. Most profound alterations of the FA profile were observed in patients with impaired graft function (glomerular filtration rate < 45 mL/min). The study demonstrated significant disorders of the FA profile in kidney transplant recipients, that might contribute to cardio-vascular risk in this vulnerable patient population. 相似文献