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81.
82.
早产儿视网膜病变伴黄斑裂孔的视网膜脱离 总被引:2,自引:0,他引:2
目的:描述早产儿视网膜病变的黄斑裂孔视网膜脱离及其手术处理和疗效。方法:回顾性分析4例早产儿视网膜病变患儿和1例表现为早产儿视网膜病变的足月儿。均出现伴黄斑裂孔视网膜脱离并且接受手术治疗。结果:4例早产儿视网膜病变的平均孕周是26周。5例患儿发现黄斑裂孔前均有玻璃体手术史。4例再次手术治疗的患儿视网膜部分或完全复位。有走动的视力。结论:采用玻璃体手术合并气-液交换不能闭合婴儿中因早产儿视网膜病变引起视网膜脱离的黄斑裂孔。非热性黄斑部巩膜扣带术能封闭裂孔和复位视网膜。可能是值得选择的方法。 相似文献
83.
S-allylcysteine scavenges singlet oxygen and hypochlorous acid and protects LLC-PK(1) cells of potassium dichromate-induced toxicity. 总被引:1,自引:0,他引:1
Omar Noel Medina-Campos Diana Barrera Sabina Segoviano-Murillo Diana Rocha Perla D. Maldonado Nicandro Mendoza-Patiño José Pedraza-Chaverri 《Food and chemical toxicology》2007,45(10):2030-2039
It has been found that S-allylcysteine (SAC), a garlic-derived compound, has in vivo and in vitro antioxidant properties. In addition, it is known that SAC is able to scavenge different reactive oxygen or nitrogen species including superoxide anion (O(2)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radical (OH()), and peroxynitrite anion (ONOO(-)) although the IC(5O) values for each reactive species has not been calculated and the potential ability of SAC to scavenge singlet oxygen ((1)O(2)) and hypochlorous acid (HOCl) has not been explored. The purposes of this work was (a) to explore the potential ability of SAC to scavenge (1)O(2) and HOCl, (b) to further characterize the O(2)(-), H(2)O(2), OH(), and ONOO(-) scavenging ability of SAC by measuring the IC(50) values using in vitro assays, and (c) to explore the potential ability of SAC to ameliorate the potassium dichromate (K(2)Cr(2)O(7))-induced cytotoxicity in LLC-PK1 cells in which oxidative stress is involved. The scavenging activity was compared against the following reference compounds: N-acetylcysteine for O(2)(-), sodium pyruvate for H(2)O(2), dimethylthiourea for OH(), lipoic acid and glutathione for (1)O(2), lipoic acid for HOCl, and penicillamine for ONOO(-). It was found that SAC was able to scavenge concentration-dependently all the species assayed with the following IC(5O) (mean+/-SEM, mM): O(2)(-) (14.49+/-1.67), H(2)O(2) (68+/-1.92), OH() (0.68+/-0.06), (1)O(2) (1.93+/-0.27), HOCl (2.86+/-0.15), and ONOO(-) (0.80+/-0.05). When the ability of SAC to scavenge these species was compared to those of the reference compounds it was found that the efficacy of SAC (a) to scavenge O(2)(-), H(2)O(2), OH(), and ONOO(-) was lower, (b) to scavenge HOCl was similar, and (c) to scavenge (1)O(2) was higher. In addition, it was found that SAC was able to prevent K(2)Cr(2)O(7)-induced toxicity in LLC-PK1 cells in culture. It was showed for the first time that SAC is able to scavenge (1)O(2) and HOCl and to ameliorate the K(2)Cr(2)O(7)-induced toxicity. 相似文献
84.
Breast cancer is the most commonly diagnosed malignancy in women, with triple-negative breast cancer (TNBC) accounting for 10–20% of cases. Historically, fewer treatment options have existed for this subtype of breast cancer, with cytotoxic chemotherapy playing a predominant role. This article aims to review the current treatment paradigm for curative-intent TNBC, while also reviewing potential future developments in this landscape. In addition to chemotherapy, recent advances in the understanding of the molecular biology of TNBC have led to promising new studies of targeted and immune checkpoint inhibitor therapies in the curative-intent setting. The appropriate selection of TNBC patient subgroups with a higher likelihood of benefit from treatment is critical to identify the best treatment approach. 相似文献
85.
Khalil B. Ramadi Yassir A. Mohamed Ashraf Al-Sbiei Saeeda Almarzooqi Ghada Bashir Aisha Al Dhanhani 《Nanotoxicology》2016,10(8):1061-1074
Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1–20?mg/kg), on the early acute (4–24?h post-exposure) and late phase response (96?h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2?mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24?h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24?h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP. 相似文献
86.
Pavel Gershkovich Bashir Qadri Avihai Yacovan Shimon Amselem Amnon Hoffman 《European journal of pharmaceutical sciences》2007,31(5):298-305
The aim of this article was to investigate the role of intestinal lymphatic transport in the oral bioavailability of two structurally similar synthetic lipophilic cannabinoids: dexanabinol and PRS-211,220. For this purpose, the long chain triglyceride (LCT) solubility and affinity to chylomicrons ex vivo of both cannabinoids were evaluated. Their oral bioavailability was assessed in rats following administration in a lipid-free and a LCT-based formulation. The intestinal lymphatic transport of these two molecules was also directly measured in a freely moving rat model. LCT solubility of dexanabinol and PRS-211,220 was 7.9 ± 0.2 and 95.8 ± 5.3 mg/g, respectively. The uptake by chylomicrons was moderate (31.6 ± 5.2%) and high (66.1 ± 2.4%), respectively. The bioavailability of dexanabinol (37%) was not affected by LCT solution, whereas administration of PRS-211,220 in LCT improved the absolute oral bioavailability three-fold (from 13 to 35%) in comparison to the lipid-free formulation. The intestinal lymphatic transport of dexanabinol and PRS-211,220 was 7.5 ± 0.8 and 60.7 ± 6.8% of the absorbed dose, respectively. In conclusion, despite structural similarity and similar lipophilicity, dexanabinol and PRS-211,220 exhibited a very diverse pattern of oral absorption, and the lymphatic system played quite a different role in the oral bioavailability of these molecules. The low lymphatic transport of dexanabinol is likely driven by relatively lower affinity to chylomicrons and lower LCT solubility. 相似文献
87.
88.
89.
Omar SZ Qvist R Khaing SL Muniandy S Bhalla S 《The journal of obstetrics and gynaecology research》2008,34(2):174-178
AIM: The aim of the present study was to determine the existence or prevalence of thrombophilic markers such as Factor V Leiden, prothrombin G20210A, protein S, protein C, activated protein C and anti-thrombin in pre-eclampsia and pregnancy-induced hypertensive patients. METHODS: Blood samples were collected from a total number of 124 women at the maternity unit, University of Malaya Medical Center. These included 49 patients with pre-eclampsia, 63 patients with pregnancy-induced hypertension and 12 normal pregnant women. DNA was extracted from the blood samples. Factor V Leiden (Taq I) and prothrombin G20210A (Hind III) genotyping was done on polymerase chain reaction-restriction fragment length polymorphism. Anti-thrombin activity and the concentrations of protein C, protein S and activated protein C were measured using the IL Coagulation System (Hemosil). RESULTS: Of the 124 subjects, one pre-eclampsia patient was homozygous for Factor V Leiden mutation but prothrombin G20210A mutation was not present in any of the subjects. The subject with Factor V Leiden mutation also had a low activated protein C resistance and a low protein S concentration. CONCLUSIONS: Factor V Leiden mutation is present in the Asian population and may very well serve as one of the genetic factors responsible for pre-eclampsia and other adverse pregnancy outcomes. 相似文献
90.
Tan PC Valiapan SD Tay PY Omar SZ 《BJOG : an international journal of obstetrics and gynaecology》2007,114(7):824-832
Objective To compare concurrent oxytocin with dinoprostone pessary versus dinoprostone pessary in labour induction for nulliparas with an unfavourable cervix.
Design A randomised double-blind study.
Setting University Malaya Medical Centre, Malaysia.
Population Nulliparas at term with intact membranes, Bishop score ≤ 6 and admitted for labour induction.
Methods All women received 3 mg dinoprostone pessary for labour induction. Those randomised to the oxytocin arm received oxytocin infusion started at 1 mu/minute and doubled every 30 minutes to a maximum 16 mu/minute. Women assigned to placebo received identical volume of saline infusion. After 6 hours, infusion was stopped and vaginal reassessment performed to guide further management.
Main outcome measures Primary outcome was vaginal delivery within 24 hours.
Results Concurrent oxytocin infusion with dinoprostone pessary did not significantly increase vaginal delivery rate within 24 hours (48.6 versus 35.9%; P = 0.07, relative risk [RR] 1.4 [95% CI 1.0–1.9]). It reduced the requirement for repeat dinoprostone (37.1 versus 61.2%; P = 0.001, RR 0.61 [95% CI 0.45–0.81]) and improved maternal satisfaction with the birth process (median score of 3 versus 5 on a 10-point visual analogue scale, P = 0.007). Caesarean rates were not different (41.9 versus 44.7%, P = 0.52).
Conclusions Labour induction with concurrent oxytocin infusion and vaginal dinoprostone could be considered for nulliparas with an unfavourable cervix. Larger studies are needed. 相似文献
Design A randomised double-blind study.
Setting University Malaya Medical Centre, Malaysia.
Population Nulliparas at term with intact membranes, Bishop score ≤ 6 and admitted for labour induction.
Methods All women received 3 mg dinoprostone pessary for labour induction. Those randomised to the oxytocin arm received oxytocin infusion started at 1 mu/minute and doubled every 30 minutes to a maximum 16 mu/minute. Women assigned to placebo received identical volume of saline infusion. After 6 hours, infusion was stopped and vaginal reassessment performed to guide further management.
Main outcome measures Primary outcome was vaginal delivery within 24 hours.
Results Concurrent oxytocin infusion with dinoprostone pessary did not significantly increase vaginal delivery rate within 24 hours (48.6 versus 35.9%; P = 0.07, relative risk [RR] 1.4 [95% CI 1.0–1.9]). It reduced the requirement for repeat dinoprostone (37.1 versus 61.2%; P = 0.001, RR 0.61 [95% CI 0.45–0.81]) and improved maternal satisfaction with the birth process (median score of 3 versus 5 on a 10-point visual analogue scale, P = 0.007). Caesarean rates were not different (41.9 versus 44.7%, P = 0.52).
Conclusions Labour induction with concurrent oxytocin infusion and vaginal dinoprostone could be considered for nulliparas with an unfavourable cervix. Larger studies are needed. 相似文献