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101.
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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Derek Leong Ali A. Sovari Ashkan Ehdaie Tarun Chakravarty Qiang Liu Hasan Jilaihawi Rajendra Makkar Xunzhang Wang Eugenio Cingolani Michael Shehata 《Journal of interventional cardiac electrophysiology》2018,52(1):111-116
Background
Damage to the cardiac conduction system requiring permanent pacemaker (PPM) implantation is a known adverse outcome of transcatheter aortic valve replacement (TAVR). A permanent-temporary pacemaker (PTPM) is a device that involves an active-fixation lead attached to an external pulse generator taped to the skin. We reviewed the utility of PTPMs as a temporary bridge measure after TAVR in patients with conduction abnormalities that do not meet conventional criteria for PPM placement.Methods
Between January 01, 2013 and December 31, 2015, we analyzed 67 patients who received PTPM after TAVR. Baseline demographics, comorbidities, type and size of the valve, pre-TAVR electrocardiograms (ECGs), post-TAVR ECGs at 1 day, 1 month, and 6 months, and pacemaker interrogation results were reviewed for each patient if available.Results
The mean age of patients was 80.5?±?9.1 years. PTPM were placed for 2.3?±?2.4 days. Among these patients, 44.8% (n?=?30) received a PPM prior to discharge. Male gender (OR 2.84, 95% CI 1.05–7.69, p?=?0.05) and an increase in QRS duration post-TAVR (p?=?0.01) were associated with PPM placement. Pacemaker interrogation data of 11 patients with PPM revealed that 27% (n?=?3) had <?1% V-pacing requirements and <?10% A-pacing requirements.Conclusions
In post-TAVR patients who develop conduction abnormalities that do not meet conventional PPM implantation indications, PTPM safely provides a time period for further assessment and may prevent unnecessary PPM implantation. Male gender and an increase in QRS duration post-TAVR are associated with PPM implantation. Additionally, some patients may recover from their conduction disturbances and demonstrate low pacemaker utilization.105.
106.
Childhood obesity is a growing epidemic in the United States, and is associated with an increased risk of lower-extremity physeal fractures, and fractures requiring operative intervention. However, no study has assessed the risk upper extremity physeal fractures among overweight children. Our purpose was to compare the following upper-extremity fracture characteristics in overweight and obese children with those of normal-weight/underweight children (herein, “normal weight”): mechanism of injury, anatomical location, fracture pattern, physeal involvement, and treatment types. We hypothesized that overweight and obese children would be higher risk for physeal and complete fractures with low-energy mechanisms and would therefore more frequently require operative intervention compared with normal-weight children.We performed a cross-sectional review of our database of 608 patients aged 2 to 16 years, and included patients who sustained isolated upper-extremity fractures at our level-1 pediatric tertiary care center from January 2014 to August 2017. Excluded were patients who sustained pathologic fractures and those without basic demographic or radiologic information. Using body mass index percentile for age and sex, we categorized patients as obese (≥95th percentile), overweight (85th to <95th percentile), normal weight (5th to <85th percentile), or underweight (<5th percentile). The obese and overweight groups were analyzed both separately and as a combined overweight/obese group. Demographic data included age, sex, height, and weight. Fractures were classified based on fracture location, fracture pattern (transverse, comminuted, buckle, greenstick, avulsion, or oblique), physeal involvement, and treatment type. Of the 608 patients, 58% were normal weight, 23% were overweight, and 19% were obese. There were no differences in the mean ages or sex distributions among the 3 groups.Among patients with low-energy mechanisms of injury, overweight/obese patients had significantly greater proportions of complete fractures compared with normal-weight children (complete: 65% vs 55%, P = .001; transverse: 43% vs 27%, P = .006). In addition, the overweight/obese group sustained significantly more upper-extremity physeal fractures (37%) than did the normal-weight group (23%) (P = .007).Compared with those in normal-weight children, upper-extremity fracture patterns differ in overweight and obese children, who have higher risk of physeal injuries and complete fractures caused by low-energy mechanisms.Level of Evidence: Level III, retrospective comparative study. 相似文献
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108.
Rik Willems Margaret L Morck Derek V Exner Sarah M Rose Anne M Gillis 《Heart rhythm》2004,1(4):414-421
OBJECTIVES: The purpose of this study was to evaluate the frequency and clinical significance of ventricular high-rate (VHR) episodes (ventricular rate >162 bpm) in patients with symptomatic bradycardia and paroxysmal atrial fibrillation (AF). BACKGROUND: Newer pacemakers have enhanced diagnostic features that permit detection and storage of detailed information about the frequency, duration, and time of onset of multiple episodes of AF, atrial tachycardia (AT), and ventricular tachycardia (VT). However, the prevalence and prognostic value of AF associated with rapid ventricular rates in the pacemaker population are unknown. METHODS: We prospectively followed 125 patients who received a Medtronic AT 500/501 pacemaker for symptomatic bradycardia and paroxysmal AF. RESULTS: AF recurred in 112 patients (90%) during 22 +/- 8 months of follow-up. A total of 1,324 VHR episodes occurred in 38 patients (30%). Episodes with available electrograms (n = 560) were reviewed and classified as AF (n = 279; 50%), AT (n = 266; 47%) or VT (n = 15; 3%). AF burden was higher in patients with VHR episodes (median 1.9 vs 0.2 hours/day; P < .001). After controlling for AT/AF burden and heart disease, VHR episodes were a significant independent predictor of hospitalization for cardiovascular symptoms (odds ratio 2.92, 95% confidence interval 1.33-6.38; P = .007). Heart rate control improved over time in the cohort, and the frequency of VHR episodes decreased during follow-up (P < .001). CONCLUSIONS: VHR episodes documented in the pacemaker diagnostics identify a high-risk subgroup of patients with AF. Monitoring VHR episodes may be useful for identifying pacemaker patients with AF who require more vigilant monitoring, additional investigations, and/or additional interventions. 相似文献
109.
We have compared results obtained with an uncalibrated respiratory inductance plethysmograph (RIP) with those of a face mask and pneumotachograph (PNT) for the computerized measurement of the time to reach peak tidal expiratory flow as a ratio of total expiratory time (tpTEF:tE). Simultaneous measurements were made in 32 healthy neonates aged 0–3 weeks, 35 healthy infants aged 5–82 weeks, and 28 infants aged 15–94 weeks with physician diagnosed recurrent wheeze. The group mean (±SD) values of tpTEF:tE determined using a PNT were 0.455 (±0.129), 0.263 (±0.077), and 0.232 (±0.089) for the neonates, healthy infants and infants with recurrent wheeze respectively. RIP gave mean (±SD) values that were 0.055 (±0.044) and 0.025 (±0.104) lower than the PNT in healthy neonates and infants with recurrent wheeze respectively; RIP values were 0.002 (±0.073) higher in the healthy infants over 4 weeks of age than measurements by PNT. Although the difference between the two measurements was not related to the thoracoabdominal phase angle, as measured from Lissajous figures, examination of the RIP ribcage and abdominal signals revealed that many healthy subjects, while appearing clinically in phase, had ribcage and abdominal signals that differed markedly from each other in terms of convexity/concavity during early expiration. This may explain the lack of agreement between the two methods. We conclude that uncalibrated RIP should be used with caution for the determination of tpTEF:tE, even in subjects whose ribcage and abdomen appear to move synchronously. The measurement of tpTEF:tE did not differentiate between the healthy infants and infants with recurrent wheezing. Pediatr Pulmonol. 1995; 20:119–124 . © 1995 Wiley-Liss, Inc. 相似文献
110.
Amit K. Patel Risa M. Broyer Cassidy D. Lee Tianlun Lu Mikaela J. Louie Anna La Torre Hassan Al-Ali Mai T. Vu Katherine L. Mitchell Karl J. Wahlin Cynthia A. Berlinicke Vinod Jaskula-Ranga Yang Hu Xin Duan Santiago Vilar John L. Bixby Robert N. Weinreb Vance P. Lemmon Donald J. Zack Derek S. Welsbie 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(52):33597