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排序方式: 共有861条查询结果,搜索用时 15 毫秒
31.
32.
Gordana Leposavić Milica Perišić Nanut Ivan Pilipović Duško Kosec Nevena Arsenović-Ranin Zorica Stojić-Vukanić Jasmina Djikić Mirjana Nacka-Aleksić 《Immunobiology》2014
This study explores the role of ovarian hormones in the phenotypic shaping of peripheral T-cell pool over the reproductive lifespan of rats. For this purpose, 2-month-old prepubertally ovariectomised (Ox) rats, showing oestrogen and progesterone deficiency, and 11-month-old Ox rats, exhibiting only progesterone deficiency, were examined for thymus output, and cellularity and composition of major TCRαβ+ peripheral blood lymphocyte (PBL) and splenocyte subsets. Although ovariectomy increased thymic output in both 2- and 11-month-old rats, the count of both CD4+ and CD8+ PBLs and splenocytes increased only in the former. In the blood and spleen of 11-month-old Ox rats only the count of CD8+ cells increased. Although ovariectomy affected the total CD4+ count in none of the examined compartments from the 11-month-old rats, it increased CD4+FoxP3+ PBL and splenocyte relative proportions over those in the age-matched controls. The age-related differences in the cellularity and the major subset composition in Ox rats were linked to the differences in the ovarian steroid hormone levels registered in 2- and 11-month-old rats. The administration of progesterone to Ox rats during the seven days before the sacrificing confirmed contribution of this hormone deficiency to the ovariectomy-induced changes in the TCRαβ+ PBL and splenocyte pool from 11-month-old rats. The expansion of the CD8+ splenocyte subset in the 11-month-old Ox rats reflected increases in cellularity of memory and, particularly, naïve cells. This was due to greater thymic output of CD8+ cells and homeostatic proliferation than apoptosis in 11-month-old Ox rats when compared with age-matched sham-Ox control rats. The homeostatic changes within CD8+ splenocyte pool from 11-month-old Ox rats, most likely, reflected the enhanced splenic IL-7 and TGF-β mRNA expression. Overall, in adult female rats, circulating oestrogen and progesterone provide maintenance of T-cell counts, a diversity of T-cell repertoire, and the main T-cell subset composition in the periphery. Progesterone deficiency affects mainly the CD8+ lymphocyte compartment through increasing thymic CD8+ cell export and upsetting homeostatic regulation within the CD8+ splenocyte pool. These alterations were reversible through progesterone supplementation. 相似文献
33.
目的:对10例大肠癌新鲜标本的原发癌组织和转移癌组织中肿瘤干细胞( cancer stem cell, CSC)的含量进行检测并分选,为进一步探讨转移肿瘤干细胞( migrating cancer stem cell, MCSC)的生物功能和机制奠定基础。方法应用流式抗体CD133-PE和CD44-FITC分别标记大肠癌原发癌组织和转移癌组织细胞悬液,应用流式细胞仪检测CD133-PE和CD44-FITC阳性细胞的含量并对其进行分选。结果在大肠癌原发癌组织和转移癌组织中均存在一定比例的CD133和CD44阳性细胞,转移癌组织中CSC比例高于原发癌组织(P<0.05)。结论大肠癌原发癌组织和转移癌组织中均存在CSC,转移癌组织中CSC比例明显高于原发癌组织,提示CSC参与大肠癌的转移过程并发挥作用。 相似文献
34.
Purpose To determine the demand and preferences of infertility patients for sex selection for nonmedical reasons, and to investigate
the relation between these choices and their demographic and socioeconomic characteristics.
Methods A cross-sectional, self-administered survey by mail was conducted at a University hospital-based fertility center of 1,350
consecutive women who presented for infertility care, to assess patient demand and preferences for sex selection.
Results Of respondents, 49% wanted to select the sex of their next child for no added cost. Of these patients, 56% had no living children
and 37% had children all of one sex. After adjustment for observed predictors of gender preference, we found a significant
preference for a female child among women who had only sons, had more living children, or were single. Nulliparous women did
not significantly prefer one sex over the other. Among parous women, those with only daughters significantly desired to select
a male child, whereas those with sons significantly desired to select a female child.
Conclusion There is significant demand among infertility patients for preimplantation sex selection, with a significant portion of this
demand coming from patients who do not have any children or have children all of one sex.
Presented in part at the American Society for Reproductive Medicine (ASRM) Annual Meeting, New Orleans, Louisiana, October
2006.
Financial support: none
Conflict of interest: none 相似文献
35.
Taku Wakabayashi Hisamichi Naito Tomohiro Iba Kohji Nishida Nobuyuki Takakura 《Investigative ophthalmology & visual science》2022,63(4)
PurposeCD157 (also known as Bst1) positive vascular endothelial stem cells (VESCs), which contribute to vascular regeneration, have been recently identified in mouse organs, including the retinas, brain, liver, lungs, heart, and skin. However, VESCs have not been identified in the choroid. The purpose of this study was to identify VESCs in choroidal vessels and to establish the protocol to isolate retinal and choroidal VESCs.MethodsWe established an efficient protocol to create single-cell suspensions from freshly isolated mouse retina and choroid by enzymatic digestion using dispase, collagenase, and type II collagenase. CD157-positive VESCs, defined as CD31+CD45−CD157+ cells, were sorted using fluorescence-activated cell sorting (FACS).ResultsIn mouse retina, among CD31+CD45− endothelial cells (ECs), 1.6 ± 0.2% were CD157-positive VESCs, based on FACS analysis. In mouse choroid, among CD31+CD45− ECs, 4.5 ± 0.4% were VESCs. The CD157-positive VESCs generated a higher number of EC networks compared with CD157-negative non-VESCs under vascular endothelial growth factor (VEGF) in vitro cultures. The EC network area, defined as the ratio of the CD31-positive area to the total area in each field, was 4.21 ± 0.39% (retinal VESCs) and 0.27 ± 0.12% (retinal non-VESCs), respectively (P < 0.01). The EC network area was 8.59 ± 0.78% (choroidal VESCs) and 0.14 ± 0.04% (choroidal non-VESCs), respectively (P < 0.01). The VESCs were located in large blood vessels but not in the capillaries.ConclusionsWe confirmed distinct populations of CD157-positive VESCs in both mouse retina and choroid. VESCs are located in large vessels and have the proliferative potential. The current results may open new avenues for the research and treatment of ocular vascular diseases. 相似文献
36.
Nikhil Sasidharan Marija Sumakovic Mandy Hannemann Jan Hegermann Jana F. Liewald Christian Olendrowitz Sabine Koenig Barth D. Grant Silvio O. Rizzoli Alexander Gottschalk Stefan Eimer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(46):18944-18949
Neurons secrete neuropeptides from dense core vesicles (DCVs) to modulate neuronal activity. Little is known about how neurons manage to differentially regulate the release of synaptic vesicles (SVs) and DCVs. To analyze this, we screened all Caenorhabditis elegans Rab GTPases and Tre2/Bub2/Cdc16 (TBC) domain containing GTPase-activating proteins (GAPs) for defects in DCV release from C. elegans motoneurons. rab-5 and rab-10 mutants show severe defects in DCV secretion, whereas SV exocytosis is unaffected. We identified TBC-2 and TBC-4 as putative GAPs for RAB-5 and RAB-10, respectively. Multiple Rabs and RabGAPs are typically organized in cascades that confer directionality to membrane-trafficking processes. We show here that the formation of release-competent DCVs requires a reciprocal exclusion cascade coupling RAB-5 and RAB-10, in which each of the two Rabs recruits the other’s GAP molecule. This contributes to a separation of RAB-5 and RAB-10 domains at the Golgi–endosomal interface, which is lost when either of the two GAPs is inactivated. Taken together, our data suggest that RAB-5 and RAB-10 cooperate to locally exclude each other at an essential stage during DCV sorting. 相似文献
37.
38.
Veeraya K. Tanawattanacharoen Courtney C. Choy Trevor J. Anesi Take Naseri Christina Soti‐Ulberg Muagututia S. Reupena Nicola L. Hawley 《Maternal & child nutrition》2020,16(3)
Eating habits begin forming early in life when parental beliefs and behaviours often play a major role in shaping dietary intake. We aimed to assess maternal beliefs about the cost, social status, and nutritional value of foods in Samoa—a setting with an alarming burden of childhood obesity—and to determine how those beliefs may be related to child dietary intake. Samoan mothers (n = 44) sorted photographs of 26 foods commonly consumed in children in Samoa by cost, social status, and nutritional value (healthfulness). Responses were then assessed for their association with child dietary intake (reported using a food frequency questionnaire) using Pearson correlations. Mothers indicated that traditional Samoan foods were healthier, of higher social status, and lower cost compared with non‐traditional/imported food items. Compared with nutritional experts and a market survey of food prices, mothers demonstrated strong nutritional (r = .87, 95% CI [0.68, 0.95], p < .001) and consumer (r = .84, 95% CI [0.68, 0.93], p < .001) knowledge. The perceived cost of food was more strongly associated (r = ?.37, 95% CI [?0.66, 0.02], p = .06) with child dietary intake than either healthfulness or social status, with decreasing consumption reported with increasing food cost. Our findings contradicted the notion that the high social status of imported foods may be contributing to increased intake and rising prevalence of childhood obesity in this developing country setting. Despite their nutritional knowledge, Samoan mothers may need additional support in applying their knowledge/beliefs to provide a healthy child diet, including support for access to reasonably priced healthy foods. 相似文献
39.
《Brain & development》2020,42(2):113-120
The DSM-5 confirmed that autism spectrum disorder (ASD) might be comorbid with attention-deficit/hyperactivity disorder (ADHD). This study investigated the executive function of ASD comorbid with ADHD (ASD + ADHD), ASD, and typically developed (TD) children using the Keio version of the modified Wisconsin card sorting test (KWCST). Children with ASD + ADHD (n = 43), ASD (n = 69), and TD (n = 69) were examined in two age groups: 5–9 years and 10–15 years. Both of the younger clinical groups showed significantly unfavorable scores for many indices in the second step compared to the TD group. As for the older groups, the ASD children showed significantly unfavorable scores in total errors in the second step, while the ASD + ADHD children did not show significant differences in either step. However, some index scores of the two older clinical groups were comparable to the older TD group in the second step. For the cognitive differences between clinical groups, the younger ASD + ADHD showed unfavorable scores in numbers of response cards until the first category achieved in the second step, while the older ASD showed unfavorable scores in categories achieved and perseverative errors of Nelson in the first step. For the degree of improvements in the second step, the older groups did not show significant group differences, while the younger ASD group showed significantly fewer improvements compared to the TD group. Based on these results, it is presumed that younger ASD + ADHD individuals are not sufficiently able to sustain attention and/or memory, and that the older ASD patients have difficulty in terms of flexibility. 相似文献
40.
Megumi Mathison Vivek P. Singh Maria J. Chiuchiolo Deepthi Sanagasetti Yun Mao Vivekkumar B. Patel Jianchang Yang Stephen M. Kaminsky Ronald G. Crystal Todd K. Rosengart 《The Journal of thoracic and cardiovascular surgery》2017,153(2):329-339.e3