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排序方式: 共有4549条查询结果,搜索用时 312 毫秒
191.
Effect of Asymptomatic Severe Aortic Stenosis on Outcomes of Individuals Aged 80 and Older
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Inge A. Mulder MSc Mei Li PhD Tessa de Vries MSc Tao Qin Takeshi Yanagisawa MD PhD Kazutaka Sugimoto MD PhD Antoon van den Bogaerdt PhD A. H. Jan Danser MD PhD Marieke J. H. Wermer MD PhD Arn M. J. M. van den Maagdenberg PhD Antoinette MaassenVanDenBrink PhD Michel D. Ferrari MD PhD Cenk Ayata MD PhD 《Annals of neurology》2020,88(4):771-784
195.
Kumi O. Kuroda Yuko Shiraishi Kazutaka Shinozuka 《Psychiatry and clinical neurosciences》2020,74(10):516-526
Behaviors comparable to human child maltreatment are observed widely among mammals, in which parental care is mandatory for offspring survival. This article first reviews the recent findings on the neurobiological mechanisms for nurturing (infant caregiving) behaviors in mammals. Then the major causes of attack/desertion toward infants (conspecific young) in nonhuman mammals are classified into five categories. Three of the categories are ‘adaptive’ in terms of reproductive fitness: (i) attack/desertion toward non‐offspring; (ii) attack/desertion toward biological offspring with low reproductive value; and (iii) attack/desertion toward biological offspring under unfavorable environments. The other two are nonadaptive failures of nurturing motivation, induced by: (iv) caregivers’ inexperience; or (v) dysfunction in caregivers’ brain mechanisms required for nurturing behavior. The proposed framework covering both adaptive and nonadaptive factors comprehensively classifies the varieties of mammalian infant maltreatment cases and will support the future development of tailored preventive measures for each human case. Also included are remarks that are relevant to interpretation of available animal data to humans: (1) any kind of child abuse/neglect is not justified in modern human societies, even if it is widely observed and regarded as adaptive in nonhuman animals from the viewpoint of evolutionary biology; (2) group‐level characteristics cannot be generalized to individuals; and (3) risk factors are neither deterministic nor irreversible. 相似文献
196.
Noriaki Yoshida Hiroaki Miyoshi Fumiko Arakawa Kazutaka Nakashima Keisuke Kawamoto Masao Seto Koichi Ohshima 《Hematological oncology》2020,38(5):673-679
Follicular lymphoma (FL) is a germinal center-derived B-cell lymphoma that is known to proliferate in the intrafollicular region. However, lymphoma cells can be identified in the extrafollicular regions, which are related to disease dissemination. We purified the intrafollicular and extrafollicular regions of FL cells by laser microdissection and conducted microarray analysis in order to characterize the gene expression profiles of FL cells from both regions. BCL2 and genes of germinal B-cell markers clearly separated intrafollicular and extrafollicular regions of reactive follicular hyperplasia, suggesting the adequacy of the current analysis. In FL cases, cytokine-related genes were significantly enriched in extrafollicular regions compared with those in the intrafollicular regions. In intrafollicular regions of FL, cell-cycle–related genes were enriched. We found that the FL cells in the extrafollicular region more strongly expressed IL3RA and CXCL12 than those of intrafollicular regions. The cytokines might be also derived from stroma cells in the extrafollicular regions, which may initiate activation and migration of the tumor cells to this region. Our results suggest that FL cell interaction with surrounding stroma cells plays an important role in the pathophysiology of FL and that such interactions should be a good target for therapy. 相似文献
197.
Eriko Yanagida Hiroaki Miyoshi Mai Takeuchi Noriaki Yoshida Kazutaka Nakashima Kyohei Yamada Takeshi Umeno Yasumasa Shimasaki Takuya Furuta Masao Seto Koichi Ohshima 《Hematological oncology》2020,38(5):680-688
The interaction of CD47 and signal-regulatory protein alpha (SIRPα) induces “don't eat me signal”, leading suppression of phagocytosis. This signal can affect the clinical course of malignant disease. Although CD47 and SIRPα expression are associated with clinicopathological features in several neoplasms, the investigation for adult T-cell leukemia/lymphoma (ATLL) has not been well-documented. This study aimed to declare the association between CD47 and SIRPα expression and clinicopathological features in ATLL. We performed immunostaining on 73 biopsy samples and found that CD47 is primarily expressed in tumor cells, while SIRPα is expressed in non-neoplastic stromal cells. CD47 positive cases showed significantly higher FoxP3 (P = .0232) and lower CCR4 (P = .0214). SIRPα positive cases presented significantly better overall survival than SIRPα negative cases (P = .0132). SIRPα positive cases showed significantly HLA class I (P = .0062), HLA class II (P = .0133), microenvironment PD-L1 (miPD-L1) (P = .0032), and FoxP3 (P = .0229) positivity. In univariate analysis, SIRPα expression was significantly related to prognosis (Hazard ratio [HR] 0.470; 95% confidence interval [CI] 0.253-0.870; P = .0167], although multivariate analysis did not show SIPRα as an independent prognostic factor. The expression of SIRPα on stromal cells reflects activated immune surveillance mechanism in tumor microenvironment and induce good prognosis in ATLL. More detailed studies for gene expression or genomic abnormalities will disclose clinical and biological significance of the CD47 and SIRPα in ATLL. 相似文献
198.
Iida M Nihei M Yamazaki M Sawaguchi M Honjo H Kodama I Kamiya K 《Journal of human hypertension》2008,22(4):275-281
Plasma levels of von Willebrand factor (vWF), a marker of endothelial dysfunction/damage, are elevated in high-risk hypertensive patients and in patients with severe aortic regurgitation (AR). Patients with mild-to-moderate AR, frequently detected in hypertensive elderly, have additional left ventricular morphological and functional dysfunctions. We hypothesized that hypertensive patients with mild-to-moderate AR may have enhanced endothelial and/or left ventricular dysfunctions that may lead to a deteriorated prognosis. We measured vWF, prothrombin F1+2 (F 1+2) as a marker of thrombin generation, brain natriuretic peptide (BNP) in 104 hypertensive patients with mild-to-moderate AR and 66 hypertensive patients without AR. The left ventricular diameter at systole (LVDs) and left ventricular posterior wall thickness (LVWT) were determined by echocardiography and indexed by body surface area (LVDs/BSA and LVWT/BSA). VWF (median, interquartile range (IQR) 154, 120-196%) and BNP (34.7 pg ml(-1), 15-65%) levels were greater in patients with AR than in those without AR (135, 98-175% and 20, 10.3-49 pg ml(-1)). All patients were prospectively followed up for cardiac events during the period of median 43 months (IQR 31-81). Patients with AR had an increased risk of cardiac events (regression ratio (RR) 1.87, 95% confidence interval 1.28-2.87) when compared to those without AR. A multivariate Cox hazard analysis indicated that log vWF (RR 4.93) and log BNP (RR 1.9) were independent predictors in patients with AR. VWF was an independent predictor of clinical outcome in hypertensive patients with mild-to-moderate AR. 相似文献
199.
Clinical characteristics and prognostic implications of NPM1 mutations in acute myeloid leukemia 总被引:15,自引:4,他引:15
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Suzuki T Kiyoi H Ozeki K Tomita A Yamaji S Suzuki R Kodera Y Miyawaki S Asou N Kuriyama K Yagasaki F Shimazaki C Akiyama H Nishimura M Motoji T Shinagawa K Takeshita A Ueda R Kinoshita T Emi N Naoe T 《Blood》2005,106(8):2854-2861
Recently, somatic mutations of the nucleophosmin gene (NPM1), which alter the subcellular localization of the product, have been reported in acute myeloid leukemia (AML). We analyzed the clinical significance of NPM1 mutations in comparison with cytogenetics, FLT3, NRAS, and TP53 mutations, and a partial tandem duplication of the MLL gene (MLL-TD) in 257 patients with AML. We found NPM1 mutations, including 4 novel sequence variants, in 64 of 257 (24.9%) patients. NPM1 mutations were associated with normal karyotype and with internal tandem duplication (ITD) and D835 mutations in FLT3, but not with other mutations. In 190 patients without the M3 French-American-British (FAB) subtype who were treated with the protocol of the Japan Adult Leukemia Study Group, multivariate analyses showed that the NPM1 mutation was a favorable factor for achieving complete remission but was associated with a high relapse rate. Sequential analysis using 39 paired samples obtained at diagnosis and relapse showed that NPM1 mutations were lost at relapse in 2 of the 17 patients who had NPM1 mutations at diagnosis. These results suggest that the NPM1 mutation is not necessarily an early event during leukemogenesis or that leukemia clones with NPM1 mutations are sensitive to chemotherapy. 相似文献
200.