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71.
Athanassakis I Papadimitriou L Bouris G Vassiliadis S 《Developmental and comparative immunology》2000,24(6-7):663-672
Maturation of the murine ectoplacental cone results in the development of the placental tissue which essentially consists of two trophoblastic zones, the spongiotrophoblast and labyrinthine trophoblast. In this study we attempted to investigate the action of cytokines on ectoplacental cone cell differentiation to mature trophoblast cells. After determining the cellular composition of the ectoplacental cone cell suspensions based on the expression of cytokeratin, vimentin, Mac-1, class I and class II MHC antigens, the cells were exposed to the differentiation-inducing cytokines IL-3, GM-CSF, CSF-1 and IFN-gamma. From the four factors employed, only IFN-gamma increased the levels of cytokeratin-positive cells without inducing Mac-1 expression. IL-3 increased the percentages of cytokeratin as well as Mac-1- and vimentin-positive cells whereas GM-CSF and CSF-1 preferentially promoted an increase of the Mac-1 and vimentin markers. For further analysis, ectoplacental cone cells were negatively selected for Mac-1, class I and class II antigens to exclude non-trophoblastic contaminants and thereafter treated with the same cytokines. We show here that only IFN-gamma leads the sorted ectoplacental cone cells to a pure trophoblastic population composed of 100% cytokeratin-positive cells. The specificity of IFN-gamma on this differentiation pathway is strengthened by the fact that murine maternal serum on the day of EC formation contains high levels of this cytokine, suggesting that its natural presence supports - at least phenotypically - the in vivo differentiation of EC cells to trophoblasts. 相似文献
72.
Primary gastrointestinal malignant lymphomas. A morphologic and immunohistochemical study 总被引:1,自引:0,他引:1
Thirty-nine primary gastric and 22 intestinal malignant lymphomas collected from 1969 to 1980 have been studied morphologically and immunohistochemically. Eighteen of the 61 gastrointestinal lymphomas were of low-grade malignancy (9 lymphoplasmacytoid/cytic, 3 centrocytic, 6 centroblastic/centrocytic) and 43 were of high-grade malignancy (14 centroblastic, 7 lymphoblastic, 22 immunoblastic malignant lymphomas) according to the Kiel classification. The peroxidase-antiperoxidase (PAP) method was used in 53 of the 61 cases. Twenty-seven of them revealed a monoclonal positivity for intracytoplasmic IgS: kappa light chains in 18 and lambda light chains in 7 cases. Two cases represented alpha chain disease, revealing only a heavy chain positivity. The most frequent staining pattern of the lymphoma cells was that of kappa/mu. Cells with a mixed centrocytic and plasma cell configuration (centrocytoid plasma cells) proved to be positive for intracytoplasmic IgS. Lymphoma cells of all tested cases proved to be negative for all histiocytic markers. Histologically and immunohistochemically, the Greek cases of primary gastrointestinal malignant lymphomas seem to resemble "western" type lymphomas. 相似文献
73.
Christina Spyraki Z. Papadopoulou A. Kourkoubas D. Varonos 《Naunyn-Schmiedeberg's archives of pharmacology》1985,329(2):128-134
Summary We studied the influence of different pretreatment regimens (Chlorimipramine-Cmi, electroconvulsive shock-ECS, and Cmi+ECS all regimens being applied for either 2 or 15 days) on the open field behaviour, on the striatal and on the prefrontal dopamine-PFC DA turnover in rats injected with either apomorphine-AP 25 g/kg (stimulating presynaptic DA receptors), AP 200 g/kg (stimulating postsynaptic DA receptors), or vehicle (control).In the controls, AP 25 g/kg reduced the locomotor activity and the striatal, but not the PFC DA turnover. AP 200 g/kg increased the locomotor activity and reduced the striatal but not the PFC DA turnover.Short-term pretreatment: ECS and Cmi+ECS prevented the decrease of striatal DA turnover after AP 25 g/kg. No other influence of any pretreatment on behaviour or DA-turnover became significant.Long-term pretreatment: Chronic Cmi: marginally increased the open field behaviour and marginally decreased the PFC DA turnover; significantly increased the effect of AP (200 g/kg) on striatal DA turnover and the effect of AP (25 and 200 g/kg) on PFC DA turnover. Repeated ECS: decreased locomotion and rearing and increased PFC DA turnover; increased the effect of AP (200 g/kg) on locomotion and on striatal DA turnover; decreased the effect of AP (25 and 200 g/kg) on PFC DA turnover.Chronic Cmi+ECS: decreased locomotion and rearing and marginally decreased PFC DA turnover; increased the effect of AP on hyperlocomotion and on striatal DA turnover. No other influence of any chronic pretreatment on behaviour or on DA turnover became significant.The data support the view that chronic AD therapies increase DAergic functions related to postsynaptic rather than to presynaptic structures. It is suggested that the different effects of chronic Cmi and repeated ECS on AP-evoked PFC DA turnover help to understand the different influences exerted by both treatments on rats' behaviour. 相似文献
74.
Study of serum prolactin during electroconvulsive therapy (ECT) in depressive patients revealed a greater prolactin increase after bilateral than after unilateral ECT. A linear correlation between the two types of prolactin response was found for a group of 10 patients, a finding that suggests a quantitative rather than a qualitative difference between bilateral and unilateral ECT with regard to their prolactin-releasing properties. The magnitude of prolactin response did not differ between right and left unilateral ECT, nor in a systematically studied case of postictal dysphoric excitement that occurred after right, but not after left, unilateral ECT. In this case, maximal prolactin response occurred earlier with right than with left unilateral ECT. Prolactin increase after ECT was not correlated with such factors as severity of depression nor seizure duration. 相似文献
75.
A 75 year woman with chronic vitreous hemorrhage underwent extraction of a senile cataract. Surgery was complicated by the flow of brown fluid from the vitreous to the anterior chamber, which was not entirely removed. Post-operatively there was pain, 2 mm of brown hypopyon and intraocular pressure elevation to 60 mm Hg with the preoperative diagnosis of endophthalmitis, a pars plana vitreous tap and instillation of intravitreal antibiotics was performed. Bacterial cultures were negative and the presence of erythrocyte "ghost cells" established the diagnosis of hemolytic glaucoma. As medical management proved ineffective, a pars plana vitrectomy was performed. One year post-operatively the patient had a visual acuity of 0.4-0.5, normal intraocular pressure without medication and evidence of an old branch retinal vein occlusion. The mechanism of hemolytic "ghost-cell" glaucoma in this case is discussed. 相似文献
76.
Curren Laura C. Borba Christina P. C. Henderson David C. Tompson Martha C. 《Maternal and child health journal》2022,26(5):1142-1152
Maternal and Child Health Journal - Mothers are especially vulnerable to the onset or recurrence of psychological symptoms during the postpartum period. However, protective psychosocial factors may... 相似文献
77.
Herkama Sanna Kontio Mari Sainio Miia Turunen Tiina Poskiparta Elisa Salmivalli Christina 《Prevention science》2022,23(6):954-968
Prevention Science - The long-term sustainment of bullying prevention programs has rarely been investigated. This study addresses this gap by identifying facilitators and barriers to the systematic... 相似文献
78.
79.
Ryan Gage Martin Girling-Butcher Ester Joe Moira Smith Cliona Ni Mhurchu Christina McKerchar Viliami Puloka Rachael McLean Louise Signal 《Nutrients》2021,13(1)
Snacking is a common eating behaviour, but there is little objective data about children’s snacking. We aimed to determine the frequency and context of children’s snacking (n = 158; mean age = 12.6 years) by ethnicity, gender, socioeconomic deprivation and body mass index (BMI) children. Participants wore wearable cameras that passively captured images of their surroundings every seven seconds. Images (n = 739,162) were coded for snacking episodes, defined as eating occasions in between main meals. Contextual factors analysed included: snacking location, food source, timing, social contact and screen use. Rates of total, discretionary (not recommended for consumption) and healthful (recommended for consumption) snacking were calculated using negative binomial regression. On average, children consumed 8.2 (95%CI 7.4, 9.1) snacks per day, of which 5.2 (95%CI 4.6, 5.9) were discretionary foods/beverages. Children consumed more discretionary snacks than healthful snacks in each setting and at all times, including 15.0× more discretionary snacks in public spaces and 2.4× more discretionary snacks in schools. Most snacks (68.9%) were sourced from home. Girls consumed more total, discretionary and healthful snacks than boys, and Māori and Pacific consumed fewer healthful snacks than New Zealand (NZ) Europeans. Results show that children snack frequently, and that most snacking involves discretionary food items. Our findings suggest targeting home buying behaviour and environmental changes to support healthy snacking choices. 相似文献
80.
Magdalena Hoffmann Christine Maria Schwarz Stefan Fürst Christina Starchl Elisabeth Lobmeyr Gerald Sendlhofer Marie-Madlen Jeitziner 《Nutrients》2021,13(1)
Critically ill patients in the intensive care unit (ICU) have a high risk of developing malnutrition, and this is associated with poorer clinical outcomes. In clinical practice, nutrition, including enteral nutrition (EN), is often not prioritized. Resulting from this, risks and safety issues for patients and healthcare professionals can emerge. The aim of this literature review, inspired by the Rapid Review Guidebook by Dobbins, 2017, was to identify risks and safety issues for patient safety in the management of EN in critically ill patients in the ICU. Three databases were used to identify studies between 2009 and 2020. We assessed 3495 studies for eligibility and included 62 in our narrative synthesis. Several risks and problems were identified: No use of clinical assessment or screening nutrition assessment, inadequate tube management, missing energy target, missing a nutritionist, bad hygiene and handling, wrong time management and speed, nutritional interruptions, wrong body position, gastrointestinal complication and infections, missing or not using guidelines, understaffing, and lack of education. Raising awareness of these risks is a central aspect in patient safety in ICU. Clinical experts can use a checklist with 12 identified top risks and the recommendations drawn up to carry out their own risk analysis in clinical practice. 相似文献