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1.
The purpose of this study was to determine the degree of agreement among different frequencies of blood pressure measurements (FoM) in 24-hour ambulatory blood pressure monitoring (ABPM) in their ability to obtain useful clinical information. ABPM records were obtained with a Del Mar IV Avionics device from 49 hospitalised preeclamptic women with a FoM of 7 per hour (high-FoM). With these records, we simulated two sets of data as if measurements had been recorded at a rate of 1 measurement per hour (low-FoM) and of 2 per hour (medium-FoM). Diastolic blood pressure > 89 mmHg defined hypertension and > 109 mmHg, severe hypertension The median and 25th and 75th centiles for the differences in hypertensive rate detected (expressed as percentage points) between lowFoM vs. high-FoM was 0.00 (- 3.4-3.00) and between medium-FoM vs. high-FoM,- 1.04 (- 3.7-1.5). The agreement in the detection of severely affected patients was 85% (CI 95%: 74-96) between low-FoM and high-FoM and 87% (CI 95%: 77-98), between medium-FoM and high-FoM. Average blood pressure was similar in the three FoMs studied at day-time and night-time. We did not find any strong argument to perform ABPM at a high-FoM. Lower FoM are more comfortable for the patient and could reduce equipment deterioration, while providing equivalent information to that supplied by high-FoM.  相似文献   
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Atomically thin van der Waals materials stacked with an interlayer twist have proven to be an excellent platform toward achieving gate-tunable correlated phenomena linked to the formation of flat electronic bands. In this work we demonstrate the formation of emergent correlated phases in multilayer rhombohedral graphene––a simple material that also exhibits a flat electronic band edge but without the need of having a moiré superlattice induced by twisted van der Waals layers. We show that two layers of bilayer graphene that are twisted by an arbitrary tiny angle host large (micrometer-scale) regions of uniform rhombohedral four-layer (ABCA) graphene that can be independently studied. Scanning tunneling spectroscopy reveals that ABCA graphene hosts an unprecedentedly sharp van Hove singularity of 3–5-meV half-width. We demonstrate that when this van Hove singularity straddles the Fermi level, a correlated many-body gap emerges with peak-to-peak value of 9.5 meV at charge neutrality. Mean-field theoretical calculations for model with short-ranged interactions indicate that two primary candidates for the appearance of this broken symmetry state are a charge-transfer excitonic insulator and a ferrimagnet. Finally, we show that ABCA graphene hosts surface topological helical edge states at natural interfaces with ABAB graphene which can be turned on and off with gate voltage, implying that small-angle twisted double-bilayer graphene is an ideal programmable topological quantum material.

Two-dimensional (2D) van der Waals heterostructures with an interlayer twist have provided a new avenue for observing emergent tunable many-body electron phenomena. Recent experimental realizations include twisted bilayer graphene (tBG) near the so-called “magic angle” of 1.1° (13), twisted double-bilayer graphene (tDBG) (46), ABC trilayer graphene on near-perfectly aligned hexagonal boron nitride (hBN) (ABC-tLG/hBN) (7, 8) and transition-metal dichalcogenide heterostructures (912) [with predictions on a variety of other systems (13, 14)]. All of these systems host an interplay of two phenomena––the presence of one or more van Hove singularities (which we colloquially refer to as “flat bands” henceforth) at low energy where the density of states is sharply peaked, and the existence of a moiré pattern that creates a unit cell that is about a hundred times larger than the carbon–carbon nearest-neighbor distance in graphene. The large number of electrons with quenched kinetic energy make the flat bands conducive to interaction-driven phases (15). The enlarged moiré unit cell is thought to reduce both the flat-band bandwidth and the interaction energy scales, and also introduces easily accessible integer fillings that create Mott-like insulating states (112), the relation of which to nearby superconductivity is debated. A natural question that arises from all of these works is whether the moiré pattern is a necessary condition for the observation of correlated many-body phases, or whether it is simply sufficient to further reduce the flat-band bandwidth and hence the kinetic energy in the heterostructure.In this regard, multilayer rhombohedral (ABC) graphene offers a different perspective toward achieving a flat-band edge without the use of a moiré potential (16). Indeed, in a seminal work (17), it was theoretically shown that the low-energy band structure of multilayer rhombohedral graphene has a sharply peaked density of state (DOS), with the band structure E(k)kN (where N is the number of layers) at low energy in the nearest-neighbor hopping approximation. This implies a peak in the DOS at charge neutrality in this material for N>2, with an appreciable fraction of the entire band within this peak (18). Indeed, this physics is already at play in ABC-tLG/hBN (7, 8), where some of the flatness of the bands comes from the intrinsic band structure of ABC graphene, which is then further flattened and isolated by the moiré pattern from the hBN alignment. A facile alternative to flatten the bandwidth without introducing a moiré potential is to simply increase the number of layers of the rhombohedral stacked graphene. Unfortunately, isolating rhombohedral stacked graphene of any thickness is extremely difficult as it is less energetically favorable than the multilayer counterpart, Bernal stacked graphene. Since the difference between rhombohedral and Bernal graphene is simply a lattice shift, and the interlayer van der Waals forces are weak, it is well known that rhombohedral graphene reverts to the Bernal form when samples are processed with heat, pressure, or while performing lithography (19). In this work, we show that twisting two sheets of tDBG by a tiny (<0.1°) angle is a simple and robust method to create large area (up to micrometer-scale) rhombohedral graphene of four-layer thickness (ABCA graphene). We present gate-tunable scanning tunneling microscopy and spectroscopy (STM/STS) measurements at 5.7 K on these regions. We show that correlated phases can be achieved without the need for a moiré pattern and that rhombohedral graphene has unique topological properties.  相似文献   
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OBJECTIVES: To determine if periodontal disease (PD) is a risk factor for premature labor, low birth weight, or preeclampsia, and to look for a potential association between the different clinical forms of PD and the obstetric results indicated. METHODS: This is an analytical, cross-sectional and prospective study of all women who gave birth in Dr. José Penna Hospital, in the city of Bahía Blanca, Argentina, between 1 February and 18 July 2003 and between 1 March and 31 May 2004. Women who met the inclusion criteria (being over 18 years old, having at least 18 teeth, not being diabetic, and having had children who survived labor) underwent a dental exam to look for hemorrhage when teeth were probed, loose teeth, or inflammation of the gums, and any loss of insertion was measured clinically. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated, and the results were adjusted according to smoking status and the presence or absence of anemia. RESULTS: A total of 2,003 births and 1,982 labor episodes were registered. In all, 420 women (21.2%) were excluded from the study because they did not meet the inclusion criteria or because no diagnostic exam could be carried out. Of the 1,562 women who were examined, 809 (51.8%) had at least one of the problems being sought; of these women, 274 (17.5%) had severe periodontal disease, and 535 (34.3%) had gingivitis. In all, there were 149 (9.5%) cases of premature labor; 161 (10.3%) cases of low birth weight, and 157 (10.0%) cases of preeclampsia. No association was noted between PD and premature labor (OR = 1.06; 95% CI: 0.74 to 1.50), low birth weight (OR = 1.05; 95% CI: 0.74 to 1.47), or preeclampsia (OR = 0.99; 95% CI: 0.70 to 1.40). The risk of giving birth to an infant with low birth weight in the subgroup of women who smoked more than 10 cigarettes a day was greater among women who had severe PD than among those who had good oral health (OR = 3.81; 95% CI: 1.46 to 10.05; P = 0.001). Anemia was found to be a risk factor for low birth weight (OR = 1.74; IC 95%: 1.03 to 2.94; P = 0.02). CONCLUSIONS: No significant association was found between PD and premature labor, low birth weight, or preeclampsia.  相似文献   
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We describe a primary rhinopharyngeal tuberculosis case in a woman who presented with an asymptomatic mass found incidentally on a MRI scan. Histopathological examination of the biopsy specimen showed granulomatous inflammation and caseous necrosis. Anti-tuberculosis therapy was applied for a 6-month period, after which nasopharyngeal examination was normal. This case supports the necessity of including tuberculosis in the differential diagnosis for a rhinopharyngeal mass.  相似文献   
6.
Minimalistic splint design: a rationale told in a personal style.   总被引:1,自引:0,他引:1  
Theoretic clinical reasoning is becoming increasingly important in splint construction. The purpose of this paper is to present an algorithm of decision steps that will help therapists consider all aspects of splint making proactively, so that they can take the necessary steps to be successful. A decision flowchart is presented and discussed in detail. An extra dimension of splint design is emphasized-namely, frugality in structure, technique, and cost. The paper concludes that the use of a comprehensive decision algorithm provides the basis for successful working technique and that the ability to create minimal-design splints is more a state of mind than a technical skill.  相似文献   
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BackgroundAdrenal venous sampling (AVS) is the gold standard for preoperative differentiation between unilateral and bilateral primary aldosteronism (PA). However, results are sometimes vitiated by failing to access the right adrenal vein.Materials and methodsThe present study assumed that clinical decisions can be made with incomplete AVS data, by comparing aldosterone/cortisol (A/C) ratio in both left and right adrenal veins with that in the inferior vena cava (LAV/IVC and RAV/IVC). Receiver operation characteristic (ROC) curve and scatterplot were used to certify the upper and lower cutoffs and to analyze the significance of discrimination. One hundred and sixty patients diagnosed with PA from April 2017 to June 2018 underwent AVS in the Urology Department of West China Hospital, Chengdu, China. One hundred and eleven with complete AVS data were divided into 3 groups: left-sided (N = 40), right-sided (N = 29) and bilateral (N = 42). We also collected patients from September 2018 to April 2019 in our department as validation cohort to test our hypothesis.ResultsOn the basis of LAV/IVC, RAV/IVC and diagnostic category, upper cutoff was 1.14 (50% sensitivity and 100% specificity) and lower cutoff 0.07 (27.5% sensitivity and 100% specificity) for LAV/IVC, and 1.04 (55% sensitivity and 100% specificity) and 0.08 (40% sensitivity and 100% specificity), respectively, for RAV/IVC.ConclusionThe diagnostic model in this study contributes to clinical decision-making in patients with only partial PA with incomplete AVS data.  相似文献   
10.
Since the first silk suture material acting as a nidus for the development of subsequent common bile duct stones after cholecystectomy was described in 1897, several investigators have reported that suture materials may cause choledocholithiasis. Silk, chromic catgut, parasites, and other foreign bodies are known occasionally to form such niduses in the common bile duct. Surgical hemostatic clips have been used widely and generally are considered very safe. The first case of postcholecystectomy clip migration was reported in 1979. Its exact pathogenesis remains unknown; it generally is agreed that bile duct injuries, inappropriate clip placements, subclinical bile leak, and infections also have been postulated to contribute to clip migration. We report an unusual case in which the core of a biliary calculus in the common bile duct was found to contain a surgical clip. This case illustrates the potentially abrupt and late development of clip-related gallstones and highlights the need for long-term follow-up evaluation.  相似文献   
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