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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
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We report a case of a 44-year-old woman who had coexisting distinct and separate primary tumors of the bladder: a leiomyosarcoma and a transitional cell carcinoma (urothelial cancer). The patient presented with macroscopic hematuria. A computed tomography scan of the pelvis showed a bladder mass along the left anterolateral wall. A transurethral resection of the bladder was performed. A pathological examination revealed that the mass was leiomyosarcoma. The patient underwent radical cystectomy with ileal conduit diversion. The urinary cystectomy specimen revealed an 11 cm x 6 cm x 5 cm solid mass on the left anterolateral wall and two 1-cm papillary tumors with different localization on the right and left lateral walls of the urinary bladder. Pathological examination revealed that the masses were high-grade leiomyosarcoma and urothelial cancer. Because of the differences in the histogenesis and prognosis, such cases should be differentiated from cases of carcinosarcoma of the urinary bladder. Synchronous occurrence of urothelial cancer and sarcoma as two separate primary tumors in the bladder is very rare. To our knowledge, seven cases of coexisting sarcoma and transitional cell carcinoma of the urinary bladder have been reported in the literature. 相似文献
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Xu Wang Ziqiang Tan Yuanhu Pan Awais Ihsan Qianying Liu Lingli Huang Guyue Cheng Dongmei Chen Yanfei Tao Zhenli Liu Zonghui Yuan 《Journal of applied toxicology : JAT》2015,35(11):1415-1426
Aditoprim (ADP), a new developed dihydrofolate reductase (DHFR) inhibitor, has great potential in clinical veterinary medicine because of its greater pharmacokinetic properties than structural analogs. Preclinical toxicology studies were performed to assess the safety of ADP including an acute oral toxicity test, a subchronic toxicity test and five mutagenicity tests. In the acute oral toxicity test, ADP was administered singly by oral gavage to Wistar rats and Kunming mice. The LD50 calculated was 1400 mg kg–1 body weight (BW) day–1 in rats and 1130 mg kg–1 BW day–1 in mice. In a subchronic study, Wistar rats were administered ADP at dose levels of 0, 20, 100 and 1000 mg kg–1 diet for 90 days. Significant decreases were observed on body weight and food efficiency in the high‐dose group. Treatment‐related changes in clinical serum biochemistry were found in the medium‐ and high‐dose groups. Significant increases in the relative weights of livers and kidneys in females and testis in males in the 1000 mg kg–1 diet, and significant decrease in relative weights of livers in males in the 100 mg kg–1 diet were noted. Histopathological observations revealed that the 1000 mg kg–1 ADP diet could induce lymphocytic infiltration and hepatocytic necrosis near the hepatic portal area. The genotoxicity of ADP was negative in tests, such as the bacterial reverse mutation assay, mice bone marrow erythrocyte micronucleus assay, in vitro chromosomal aberration test, in vitro cho/hgprt mammalian cell mutagenesis assay and mice testicle cells chromosome aberration. Based on the subchronic study, the no‐observed‐adverse‐effect level for ADP was a 20 mg kg–1 diet, which is about 1.44‐1.53 mg kg–1 BW day–1 in rats. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Cebi Alper Han Demir Ferhat Ikbal Mevlit Kalyoncu Mukaddes 《Clinical rheumatology》2021,40(5):1975-1981
Clinical Rheumatology - Immunoglobulin A vasculitis (IgAV) is the most common form of childhood systemic vasculitis. It is mostly self-limiting and characterized by skin, joint, gastrointestinal... 相似文献
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Jack R. Cornelius Ihsan M. Salloum Nancy L. Day Michael E. Thase J. John Mann 《Alcoholism, clinical and experimental research》1996,20(8):1451-1455
The aims of this study were (1) to comprehensively characterize a population of alcoholics with major depression in a psychiatric hospital, (2) to determine the prevalence of suicidal behavior in this sample, and (3) to determine whether quantity of alcohol ingested was associated with level of suicidality. Ratings of drinking, depression, and suicidality were obtained using both self-rated and observer-rated instruments. The prevalence of suicide attempts in the week before hospitalization was remarkably high, approaching 40%, whereas 70% had made a suicide attempt at some point in their lifetime. These suicide attempts were typically impulsive in nature, involving little if any premeditation. Most subjects reported drinking more heavily than usual on the day of their suicide attempt. Recent suicidal behavior was significantly associated with recent very heavy drinking (<70 drinks per week) and with number of drinks per drinking day. Quantity of drinking per drinking day was also significantly higher in those making a recent suicide attempt. However, no association was found between quantity of alcohol consumption and suicidal ideation. These findings suggest that recent heavy alcohol use primarily affects suicidality by increasing the likelihood of acting on suicidal ideation rather than by inducing suicidal ideation. 相似文献
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