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排序方式: 共有196条查询结果,搜索用时 10 毫秒
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Expression profile and in vitro blockade of programmed death‐1 in human papillomavirus–negative head and neck squamous cell carcinoma 下载免费PDF全文
3.
Giorgina Barbara Piccoli Gianfranca Cabiddu Rossella Attini Federica Neve Vigotti Stefania Maxia Nicola Lepori Milena Tuveri Marco Massidda Cecilia Marchi Silvia Mura Alessandra Coscia Marilisa Biolcati Pietro Gaglioti Michele Nichelatti Luciana Pibiri Giuseppe Chessa Antonello Pani Tullia Todros 《Journal of the American Society of Nephrology : JASN》2015,26(8):2011-2022
CKD is increasingly prevalent in pregnancy. In the Torino-Cagliari Observational Study (TOCOS), we assessed whether the risk for adverse pregnancy outcomes is associated with CKD by comparing pregnancy outcomes of 504 pregnancies in women with CKD to outcomes of 836 low-risk pregnancies in women without CKD. The presence of hypertension, proteinuria (>1 g/d), systemic disease, and CKD stage (at referral) were assessed at baseline. The following outcomes were studied: cesarean section, preterm delivery, and early preterm delivery; small for gestational age (SGA); need for neonatal intensive care unit (NICU); new onset of hypertension; new onset/doubling of proteinuria; CKD stage shift; “general” combined outcome (preterm delivery, NICU, SGA); and “severe” combined outcome (early preterm delivery, NICU, SGA). The risk for adverse outcomes increased across stages (for stage 1 versus stages 4–5: “general” combined outcome, 34.1% versus 90.0%; “severe” combined outcome, 21.4% versus 80.0%; P<0.001). In women with stage 1 CKD, preterm delivery was associated with baseline hypertension (odds ratio [OR], 3.42; 95% confidence interval [95% CI], 1.87 to 6.21), systemic disease (OR, 3.13; 95% CI, 1.51 to 6.50), and proteinuria (OR, 3.69; 95% CI, 1.63 to 8.36). However, stage 1 CKD remained associated with adverse pregnancy outcomes (general combined outcome) in women without baseline hypertension, proteinuria, or systemic disease (OR, 1.88; 95% CI, 1.27 to 2.79). The risk of intrauterine death did not differ between patients and controls. Findings from this prospective study suggest a “baseline risk” for adverse pregnancy-related outcomes linked to CKD. 相似文献
4.
Is renal hyperfiltration protective in chronic kidney disease‐stage 1 pregnancies? A step forward unravelling the mystery of the effect of stage 1 chronic kidney disease on pregnancy outcomes 下载免费PDF全文
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Placental expression of soluble fms-like tyrosine kinase 1 is increased in singletons and twin pregnancies with intrauterine growth restriction 总被引:1,自引:0,他引:1
Nevo O Many A Xu J Kingdom J Piccoli E Zamudio S Post M Bocking A Todros T Caniggia I 《The Journal of clinical endocrinology and metabolism》2008,93(1):285-292
OBJECTIVE: Intrauterine growth restriction (IUGR) is characterized by decreased placental perfusion. Low oxygen has been shown to increase soluble fms-like tyrosine kinase 1 (sFlt-1) expression in the human placenta. The objective of this study was to examine sFlt-1 expression in different types of IUGR pregnancies, including early-onset severe cases characterized by abnormal umbilical and uterine artery Doppler and discordant IUGR twins in which the normal cotwin represents the optimal control because both placentas share the same uterine environment. PATIENTS: Placentas from four subgroups were collected: early severe IUGR with umbilical artery absent end diastolic flow (n = 19), small for gestational age with normal uterine and umbilical artery Doppler (n = 11), severely growth-restricted dichorionic and monochorionic twins with abnormal umbilical artery Doppler (n = 9), preeclamptic twins (n = 3), and age-matched normal singletons (n = 19) and twin controls (n = 8). RESULTS: Expression of sFlt-1 mRNA and protein was significantly increased in IUGR placentas compared with small for gestational age and normal control placentas. sFlt-1 expression levels were also significantly greater in the small IUGR twin placentas from discordant twin pregnancies compared with the normal cotwin. In preeclamptic twins, sFlt-1 expression was increased in only one of the two placentas. CONCLUSIONS: Our results demonstrate that sFlt-1 expression is increased in severe IUGR placentas with abnormal umbilical artery Doppler of singletons and also in discordant IUGR twins. Reduced placental perfusion may contribute to the increased expression of sFlt-1 in IUGR pregnancies. Our data are compatible with differential sFlt-1 expression in placentas from discordant twins. 相似文献
6.
Tai X Van Laethem F Pobezinsky L Guinter T Sharrow SO Adams A Granger L Kruhlak M Lindsten T Thompson CB Feigenbaum L Singer A 《Blood》2012,119(22):5155-5163
CTLA-4 proteins contribute to the suppressor function of regulatory T cells (Tregs), but the mechanism by which they do so remains incompletely understood. In the present study, we assessed CTLA-4 protein function in both Tregs and conventional (Tconv) CD4(+) T cells. We report that CTLA-4 proteins are responsible for all 3 characteristic Treg functions of suppression, TCR hyposignaling, and anergy. However, Treg suppression and anergy only required the external domain of CTLA-4, whereas TCR hyposignaling required its internal domain. Surprisingly, TCR hyposignaling was neither required for Treg suppression nor anergy because costimulatory blockade by the external domain of CTLA-4 was sufficient for both functions. We also report that CTLA-4 proteins were localized in Tregs in submembrane vesicles that rapidly recycled to/from the cell surface, whereas CTLA-4 proteins in naive Tconv cells were retained in Golgi vesicles away from the cell membrane and had no effect on Tconv cell function. However, TCR signaling of Tconv cells released CTLA-4 proteins from Golgi retention and caused activated Tconv cells to acquire suppressor function. Therefore, the results of this study demonstrate the importance of intracellular localization for CTLA-4 protein function and reveal that CTLA-4 protein externalization imparts suppressor function to both regulatory and conventional CD4(+) T cells. 相似文献
7.
Stephan Oelhafen Aki Nikolaidis Tullia Padovani Daniela Blaser Thomas Koenig Walter J. Perrig 《Neuropsychologia》2013,51(13):2781-2790
Recent studies suggest that computerized cognitive training leads to improved performance in related but untrained tasks (i.e. transfer effects). However, most study designs prevent disentangling which of the task components are necessary for transfer. In the current study, we examined whether training on two variants of the adaptive dual n-back task would affect untrained task performance and the corresponding electrophysiological event-related potentials (ERPs). Forty three healthy young adults were trained for three weeks with a high or low interference training variant of the dual n-back task, or they were assigned to a passive control group. While n-back training with high interference led to partial improvements in the Attention Network Test (ANT), we did not find transfer to measures of working memory and fluid intelligence. ERP analysis in the n-back task and the ANT indicated overlapping processes in the P3 time range. Moreover, in the ANT, we detected increased parietal activity for the interference training group alone. In contrast, we did not find electrophysiological differences between the low interference training and the control group. These findings suggest that training on an interference control task leads to higher electrophysiological activity in the parietal cortex, which may be related to improvements in processing speed, attentional control, or both. 相似文献
8.
Guido Tavazzi Carlo Pellegrini Marco Maurelli Mirko Belliato Fabio Sciutti Andrea Bottazzi Paola Alessandra Sepe Tullia Resasco Rita Camporotondo Raffaele Bruno Fausto Baldanti Stefania Paolucci Stefano Pelenghi Giorgio Antonio Iotti Francesco Mojoli Eloisa Arbustini 《European journal of heart failure》2020,22(5):911-915
We describe the first case of acute cardiac injury directly linked to myocardial localization of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in a 69‐year‐old patient with flu‐like symptoms rapidly degenerating into respiratory distress, hypotension, and cardiogenic shock. The patient was successfully treated with venous‐arterial extracorporeal membrane oxygenation (ECMO) and mechanical ventilation. Cardiac function fully recovered in 5 days and ECMO was removed. Endomyocardial biopsy demonstrated low‐grade myocardial inflammation and viral particles in the myocardium suggesting either a viraemic phase or, alternatively, infected macrophage migration from the lung. 相似文献
9.
Pierluigi Toniutto Carlo Fabris Edmondo Falleti Annarosa Cussigh Elisabetta Fontanini Davide Bitetto Ezio Fornasiere Rosalba Minisini Tullia De Feo Francesca Marangoni Mario Pirisi 《Liver international》2008,28(2):257-263
Background/Aims: Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, being a putative steatogenic factor, may promote liver fibrosis progression in patients with chronic hepatitis C. This study aimed to verify the role of recipient MTHFR polymorphism in favouring graft fibrosis progression in patients with recurrent HCV after orthotopic liver transplantation (OLT). Methods: We studied 63 such patients, followed for >1 year. MTHFR allelic variants were determined by a polymerase chain reaction/restriction fragment length polymorphism method. Results: Recipients carrying the TT genotype had more frequently, 1‐year post‐OLT, homocysteine serum levels >23 μmol/L (P<0.05), serum triglycerides >180 mg/dL (P<0.02) and de novo diabetes mellitus (P<0.05) but not a higher frequency of graft steatosis. Time‐to‐event analysis in reaching an Ishak staging score >2 was performed by stratifying the recipients as follows: (a) patients with donor age ≤45 years, (b) patients with donor age >45 and C/* genotype, and (c) patients with donor age >45 years and TT genotype. A significant linear trend was observed, with increasing frequencies as follows: (a) 8/37, (b) 10/19 and (c) 6/7 (P=0.0005). Conclusion: The MTHFR C677T polymorphism may play a role in influencing liver fibrosis progression in patients with recurrent hepatitis C, in conjunction with donor age, but not via steatosis promotion. 相似文献
10.
De Stefano V Martinelli I Rossi E Battaglioli T Za T Mannuccio Mannucci P Leone G 《British journal of haematology》2006,135(3):386-391
Whether or not pregnant women with a previous episode of venous thromboembolism (VTE) should receive antithrombotic prophylaxis is a matter of debate. In order to estimate the rate of recurrent deep venous thrombosis (DVT) or pulmonary embolism (PE) during pregnancy and puerperium we retrospectively investigated a cohort of 1104 women with previous VTE; after a single DVT or isolated PE, 88 of them became pregnant at least once without receiving antithrombotic prophylaxis. Overall, 155 pregnancies and 120 puerperium periods without prophylaxis were recorded. There were nine recurrences during pregnancy and 10 during puerperium, with a rate of 5.8% [95% confidence interval (CI) 3.0-10.6] and 8.3% (95%CI 4.5-14.6) respectively. In pregnancy, the rate of recurrence was 7.5% (95%CI 4.0-13.7) if the first VTE was unprovoked, related to pregnancy or to oral contraceptive use, whereas no recurrence occurred if the first VTE was related to other transient risk factors. In puerperium, the rate of recurrence was 15.5% (95%CI 7.7-28.7) in women with a pregnancy-related first VTE, with a risk 3.9-times higher than in the remaining women. Inherited thrombophilia was not associated with a statistically significant increase in risk of recurrence in pregnancy or in puerperium, yet the rate of recurrence in puerperium was 14.2% (95%CI 5.7-31.4) in overall carriers of factor V Leiden and 30% (95%CI 10.7-60.3) in carriers with a pregnancy-related first VTE, with a risk 6.8 times higher than in women without thrombophilia and with a non pregnancy-related first VTE. 相似文献