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61.
62.
Osborne AH Vance D Rohling EJ Barton N Rogerson M Fello N 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(43):16444-16447
It is widely accepted that modern humans originated in sub-Saharan Africa approximately 150-200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant approximately 120-90 ka, northward dispersal likely occurred during a humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130-117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of-now buried-fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. These corridors would explain scattered findings at desert oases of Middle Stone Age Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. Here we present geochemical data that demonstrate that water in these fossil systems derived from the south during wet episodes in general, and penetrated all of the way to the Mediterranean during MIS 5e in particular. This proves the existence of an uninterrupted freshwater corridor across a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa. 相似文献
63.
We report a 64-year-old Turkish man who presented with unstable angina pectoris. Coronary angiography revealed massive intracoronary thrombus, which completely occluded the distal part of the left circumflex coronary artery. The thrombotic segment and the rest of the coronary tree were free of atherosclerosis. The patient was treated with intravenous tirofiban, a glycoprotein IIb/IIIa inhibitor. A control angiography was performed one week later and showed total dissolution of the thrombus with tirofiban therapy. 相似文献
64.
目的:探讨放射状角膜切开术在轻中度圆锥角膜治疗中光学和视力康复的效果。
方法:回顾性分析应用放射状角膜切开术治疗圆锥角膜的病例22例31眼并进行了至少12 mo的随访。测量并分析术前术后裸眼视力,最佳矫正视力,自动屈光计值,角膜曲率,角膜不规则指数以及并发症。
结果:在最后一次随访中,平均裸眼视力( logMAR)由0.86±0.34显著提升至0.30±0.29(P<0.0001),平均最佳矫正视力由0.47±0.21提升至0.17±0.23(P<0.0001)。平均角膜曲率由48.69±3.68 D 降低至44.33±3.09 D ( P<0.0001)。自动屈光计测得平均等效球镜值由-5.61±2.85D显著提升至-2.29±1.95D(P<0.0001)。在整个随访过程中,中央角膜厚度和3mm,5mm区域的角膜不规则指数均无变化。术中和术后没有观察到严重并发症。
结论:在本组病例中,放射状角膜切开术是轻中度圆锥角膜视觉康复的有效治疗方法。 相似文献
方法:回顾性分析应用放射状角膜切开术治疗圆锥角膜的病例22例31眼并进行了至少12 mo的随访。测量并分析术前术后裸眼视力,最佳矫正视力,自动屈光计值,角膜曲率,角膜不规则指数以及并发症。
结果:在最后一次随访中,平均裸眼视力( logMAR)由0.86±0.34显著提升至0.30±0.29(P<0.0001),平均最佳矫正视力由0.47±0.21提升至0.17±0.23(P<0.0001)。平均角膜曲率由48.69±3.68 D 降低至44.33±3.09 D ( P<0.0001)。自动屈光计测得平均等效球镜值由-5.61±2.85D显著提升至-2.29±1.95D(P<0.0001)。在整个随访过程中,中央角膜厚度和3mm,5mm区域的角膜不规则指数均无变化。术中和术后没有观察到严重并发症。
结论:在本组病例中,放射状角膜切开术是轻中度圆锥角膜视觉康复的有效治疗方法。 相似文献
65.
Suna Sabuncuoglu Ayse Eken Ahmet Aydin Hilal Ozgunes Hilmi Orhan 《Drug and chemical toxicology》2015,38(4):375-382
We explored the association between the activities of antioxidant enzymes and their metallic cofactors in rats treated with cisplatin. The antioxidant effects of aminoguanidine, and a combination of vitamins E and C were investigated. Plasma platin was significantly lower than liver and kidney. Cisplatin treatment caused significant increase in plasma Se-glutathione peroxidase activity. Activities of Se-glutathione peroxidase, glutathione S-transferase, catalase and Cu,Zn-superoxide dismutase have been found to be significantly decreased in liver and kidney compared to controls. Zn levels in these organs were diminished upon cisplatin treatment, while levels of Cu were unaffected. Interestingly, levels of iron, the cofactor of catalase, were found to be significantly increased in liver and kidney. Intervention with aminoguanidine or vitamins was generally prevented cisplatin-caused changes in the activity of enzymes and in the tissue levels of cofactor metals. These observations suggest that relation between activities of enzymes and levels of cofactor metals is multifactorial. 相似文献
66.
We report here a method for the synthesis of a unique hybrid gel system for the sustained delivery of P2X7 receptor (P2X7R) antagonist. P2X7R has been reported as a key mediator in inflammatory processes and controlled delivery of this molecule would be critical for the treatment of inflammatory arthritis. The hybrid gel designed here for the sustained delivery of P2X7R antagonists is based on crosslinked hydrophobic styrene-butadiene-styrene (SBS) polymer as a continuous network, where hydrogel particles prepared with hydrophilic poly(ethylene glycol) (PEG) were embedded into this system. PEG hydrogel particle-incorporated SBS gels were characterized through electron microscopy, water contact angle observations, and strong mechanical properties were confirmed through nanoindentation measurements. The release of P2X7R antagonist from these hybrid hydrogel-elastomer system demonstrated a sustained drug release profile up to 28 days at physiological pH, which was not observed in earlier reports. We obtained drug release percentages ranging from 49.72% to 93.04% which indicated the tunability of release through SBS crosslinking and hydrophilic/hydrophobic nature of SBS. This tunability is significant to achieve simultaneous improvements in drug efficacy with reduced side effects. CellTiter-Glo luminescence measurements using human kidney cells revealed that these networks are non-toxic and highly biocompatible with percent cell viabilities of higher than 85%. The approach presented here with crosslinked, amphiphilic and elastic SBS gel systems is not only promising for extended release of P2X7R antagonist but could also allow for incorporation of different molecules so that simultaneous/sequential and extended release profiles for therapeutic molecules could be achieved.We report here a method for the synthesis of a unique hybrid gel system for the sustained delivery of P2X7 receptor (P2X7R) antagonist. 相似文献
67.
Demir Arzu Meltem Aydin Fatma Acar Banu Kurt Tuba Poyraz Aylar Kiremitci Saba Gülleroglu Basak Azili Müjdem Nur Bayrakci Umut Selda 《Clinical rheumatology》2021,40(9):3817-3825
Clinical Rheumatology - Autoimmune pancreatitis (AIP) type 1 is an IgG4-related disease (IgG4-RD), characterized by inflammatory pseudotumors and histologically by dense lymphoplasmacytic... 相似文献
68.
Weidner Kathrin Behnes Michael Schupp Tobias Hoppner Jorge Ansari Uzair Mueller Julian Lindner Simon Borggrefe Martin Kim Seung-hyun Huseyinov Aydin Ellguth Dominik Akin Muharrem Meininghaus Dirk Große Bertsch Thomas Taton Gabriel Bollow Armin Reichelt Thomas Engelke Niko Reiser Linda Akin Ibrahim 《Journal of interventional cardiac electrophysiology》2022,63(1):13-20
Journal of Interventional Cardiac Electrophysiology - The study sought to assess the prognostic impact of chronic kidney disease (CKD) in patients with electrical storm (ES). ES represents a... 相似文献
69.
Acetyl salicylic acid improves somatosensory evoked potentials in streptozotocin-diabetic rats 总被引:4,自引:0,他引:4
Microalbuminuria and retinopathy was studied in a non-proteinuric diabetic population of Cameroon. Patients were enrolled on a consecutive basis in two referral hospitals in Yaoundé. Retinopathy was evaluated by direct ophthalmoscopy and biomicroscopy, and controlled by mydriatic fundus photography. Detection of microalbuminuria was carried out on an overnight urine sample using Micral II test (Boehringer Mannheim). Anthropometric and blood pressure measurements were done using validated methods. In 64 non-proteinuric diabetic patients (9 IDDM and 55 NIDDM) aged 19-70 years with known duration of diabetes of 1-23 years, the prevalence of retinopathy was 37.5%. Microalbuminuria was detected in 53.1% of patients. Microalbuminuria correlated with duration of diabetes, and blood pressure, retinopathy was positively correlated with age, and blood pressure. Retinopathy was not significantly associated with the known duration of diabetes. Retinopathy was found to be independently associated with microalbuminuria (P < 0.001) and microalbuminuria appeared to be a sensitive marker of retinopathy. The prevalence of retinopathy and microalbuminuria in this population was high. Microalbuminuria and non-proliferative retinopathy are independently associated, and are both associated with increased blood pressure levels in the study population. As shown in previous studies microalbuminuria may also be a sensitive marker of early diabetic retinopathy in African diabetic patients. 相似文献
70.
Adem Aydin Yavuz Selvi Lutfullah Besiroglu Murat Boysan Abdullah Atli Osman Ozdemir Sultan Kilic Ragıp Balaharoglu 《Journal of affective disorders》2013
It has been commonly recognized that circadian rhythm and sleep/wake cycle are causally involved in bipolar disorder. There has been a paucity of systematic research considering the relations between sleep and mood states in bipolar disorder. The current study examines the possible influences of sleep deprivation on mood states and endocrine functions among first-degree relatives of patients with bipolar disorder and healthy controls. Blood samples were taken at two time points in the consecutive mornings at predeprivation and postdeprivation periods. Participants simultaneously completed the Profiles of Mood States at two time points after giving blood samples. Plasma T3 and TSH levels increased after total sleep deprivation in both groups. Sleep deprivation induced TSH levels were reversely associated with depression–dejection among healthy controls. A paradoxical effect was detected for only the first-degree relatives of the patients that changes in plasma cortisol levels negatively linked to depression–dejection and anger–hostility scores after total sleep deprivation. Plasma DHEA levels became correlated with vigor-activity scores after sleep deprivation among first-degree relatives of bipolar patients. On the contrary, significant associations of depression–dejection, anger–hostility, and confusion–bewilderment with the baseline plasma DHEA levels became statistically trivial in the postdeprivation period. Findings suggested that first-degree relatives of patients with bipolar disorder had completely distinct characteristics with respect to sleep deprivation induced responses in terms of associations between endocrine functions and mood states as compared to individuals whose relatives had no psychiatric problems. Considering the relationships between endocrine functions and mood states among relatives of the patients, it appears like sleep deprivation changes the receptor sensitivity which probably plays a pivotal role on mood outcomes among the first-degree relatives of patients with bipolar disorder. 相似文献