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31.
Predictors of in‐hospital mortality in octogenarian patients who underwent primary percutaneous coronary intervention after ST segment elevated myocardial infarction 下载免费PDF全文
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Gandham Lakshminarayana Youssef Elmahroug Ashok Kumar Huseyin Ozan Tekin Najeh Rekik Mengge Dong Dong-Eun Lee Jonghun Yoon Taejoon Park 《Materials》2021,14(9)
For both the B2O3-Bi2O3-CaO and B2O3-Bi2O3-SrO glass systems, γ-ray and neutron attenuation qualities were evaluated. Utilizing the Phy-X/PSD program, within the 0.015–15 MeV energy range, linear attenuation coefficients (µ) and mass attenuation coefficients (μ/ρ) were calculated, and the attained μ/ρ quantities match well with respective simulation results computed by MCNPX, Geant4, and Penelope codes. Instead of B2O3/CaO or B2O3/SrO, the Bi2O3 addition causes improved γ-ray shielding competence, i.e., rise in effective atomic number (Zeff) and a fall in half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP). Exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) were derived using a geometric progression (G–P) fitting approach at 1–40 mfp penetration depths (PDs), within the 0.015–15 MeV range. Computed radiation protection efficiency (RPE) values confirm their excellent capacity for lower energy photons shielding. Comparably greater density (7.59 g/cm3), larger μ, μ/ρ, Zeff, equivalent atomic number (Zeq), and RPE, with the lowest HVL, TVL, MFP, EBFs, and EABFs derived for 30B2O3-60Bi2O3-10SrO (mol%) glass suggest it as an excellent γ-ray attenuator. Additionally, 30B2O3-60Bi2O3-10SrO (mol%) glass holds a commensurably bigger macroscopic removal cross-section for fast neutrons (ΣR) (=0.1199 cm−1), obtained by applying Phy-X/PSD for fast neutrons shielding, owing to the presence of larger wt% of ‘Bi’ (80.6813 wt%) and moderate ‘B’ (2.0869 wt%) elements in it. 70B2O3-5Bi2O3-25CaO (mol%) sample (B: 17.5887 wt%, Bi: 24.2855 wt%, Ca: 11.6436 wt%, and O: 46.4821 wt%) shows high potentiality for thermal or slow neutrons and intermediate energy neutrons capture or absorption due to comprised high wt% of ‘B’ element in it. 相似文献
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Summary In a 47-year-old male cadaver the splenic artery traveled partially through the substance of the pancreas. Additionally, the pancreas was apparently large and had an unusual shape; the neck of the organ could not be differentiated; the uncinate processus was absent; two pancreatic ducts were present. The probable reason for this combined anomaly was abnormal fusion of the ventral and dorsal pancreatic buds due to different levels of origin.
Trajet intra-pancréatique de l'artère splénique associé à des anomalies pancréatiques
Résumé Sur le cadavre d'un homme de 47 ans, l'artère splénique présentait un trajet partiel à travers le pancréas. De plus, le pancréas paraissait volumineux et avait une forme inhabituelle, il n'était pas possible de différencier le col du pancréas, le processus uncinatus était absent, il y avait deux conduits pancréatiques. La raison probable de ces variations multiples se trouverait dans la fusion anormale des bourgeons pancréatiques dorsal et ventral en raison de leurs niveaux d'origine différents.相似文献
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According to modern reinforcement learning theories, midbrain dopamine (DA) neurons are part of an adaptive system within which learned expectations filter reward-related signals to enable computation of reward prediction errors (RPEs). Recent electrophysiological data on DA neuron responses to probabilistic reward schedules inspired the idea that DA neurons might be adapting their mismatch sensitivities to reflect variances of expected rewards. Taken literally as a mathematical hypothesis, this idea contradicts reinforcement learning theory, and most computational models of basal ganglia learning. Here, we report a qualitative mathematical derivation of the implications of a generic class of circuit models for learning to compute RPEs. This analysis and concordant circuit simulations, both of which predict DA neuron responses on probabilistic schedules, support a reinterpretation of the electrophysiological data that is fully compatible with the examined class of RPE models. This reinterpretation implies a novel and readily testable prediction. 相似文献
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Berna?Musal Yucel?GurselEmail author H?Cahit?Taskiran Sema?Ozan Arif?Tuna 《BMC medical education》2004,4(1):16
Background
The objective of this study is to investigate the perceptions of first and third year medical students on self-study and reporting processes of Problem-based Learning (PBL) sessions and their usage of learning resources. 相似文献37.
In this study the authors aimed to show variations of the nutrient artery of the fibula, which is important for more effective vascularized fibular grafts. Thirty intact legs were examined to determine the number, location, and diameter of the nutrient arteries in the shaft. In 27 of these specimens (90%) there was single nutrient artery; two legs (6.6%) had double nutrient artery. In one leg (3.3%) no nutrient artery was observed. The number of nutrient arteries found on each of the surfaces was summarized as follows. Most of the nutrient arteries pierced the fibula at its medial crest, while only one entered from the posterior surface. Most nutrient arteries were near the middle third of the fibula. The most frequent diameter of the nutrient artery was 0.9-1.5 mm. The authors think that their results about the variations of the nutrient artery supplying the fibula will contribute to the clinical and vascular anatomy knowledge. 相似文献
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The pudendal nerve is a considerably large branch of the sacral plexus. There are many articles in the literature concerning the pudendal nerve in adults, but as far as we know, there is none on the branching pattern and variations in pudendal nerve anatomy in fetus. This study investigates the pudendal nerve trunking with respect to the piriformis muscle in 25 formalin-fixed fetuses (50 sides of pelves, 15 females, 10 males), ranging from 20 to 37 weeks of gestation. We investigate pudendal nerve trunking in four types: Type I-a is defined as single-trunk with the inferior rectal nerve branching proximal to the dorsal nerve of penis/clitoris (38%), Type I-b is also single-trunk with the dorsal nerve of penis/clitoris branching proximal to the inferior rectal nerve (24%), Type II is double-trunk with medial trunk as an inferior rectal nerve (34%), and Type III is triple-trunk (4%). We measured the average diameter of the main trunk of pudendal nerve in Type I-a and I-b groups to be 0.98 +/- 0.33 mm. We also measured the average length of the pudendal nerve trunks before the dorsal nerve of penis/clitoris branch to be 7.35 +/- 3.50 mm. There was no significant statistical difference in the average length, diameter, number of trunks, and pudendal nerve variations between male and female and also right and left sides of the pelves. This first and detailed fetal study of pudendal nerve trunking with respect to the piriformis muscle would be useful for educational anatomy dissections and anatomical landmark definitions for relevant clinical procedures. 相似文献
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Summary In two cases, one male and one female, muscular anomalies together with neurovascular variations were encountered in the gluteal regions, in each cadaver on the same side. In the male cadaver, there was a double piriformis muscle and high division of the sciatic nerve. In the female cadaver, in addition to these anomalies, the superior and inferior gemelli and obturator internus muscles, and the internal pudendal vessels and pudendal nerve passed behind the sacrotuberous ligament. Although duplication of the piriformis and high division of the sciatic nerve have been reported previously, to the best of our knowledge the other anomalies have not yet been reported. The abnormal relationship of the internal pudendal vessels and the pudendal nerve with the sacrotuberal ligament, as in our case, may cause venous congestion, arterial obstruction, dysfunction of penile erection and perineal neuralgia. These anomalies of the gluteal region are not only of academic interest, but may be of practical importance for surgical intervention in the area.
Anomalies musculaires et neurovasculaires de la région glutéale : un nerf pudendal atypique
Résumé Sur deux sujets — un homme et une femme — l'association d'anomalies musculaires et de variations neurovasculaires ont été observées dans la région glutéale. Sur chacun des cadavres, toutes ces particularités étaient situées du même côté. Chez le cadavre mâle, il y avait duplication du muscle piriforme et division haute associée du nerf sciatique. Chez le cadavre femelle, outre ces anomalies, les muscles jumeaux supérieur et inférieur, le muscle obturateur interne, ainsi que les vaisseaux et le nerf pudendal, passaient en arrière du ligament sacrotubéral. Si la duplication du muscle piriforme et la division haute du nerf sciatique ont déjà été rapportées, à notre connaissance les autres anomalies n'ont encore jamais été signalées. Les rapports atypiques des vaisseaux honteux internes et du nerf honteux avec le ligament sacro-tubéral comme dans notre cas, pourraient induire une congestion veineuse voire une obstruction artérielle et entraîner un dysfonctionnement du pénis et des algies périnéales. Ces anomalies de la région glutéale n'ont pas un simple intérêt académique mais peuvent être d'importance pratique pour la chirurgie de la région.相似文献
40.
Deniz Eyice Karabacak Semra Demir Osman Ozan Yeğit Ali Can Kadriye Terzioğlu Derya Ünal Müge Olgaç Raif Coşkun Bahauddin Çolakoğlu Suna Büyüköztürk Aslı Gelincik 《Allergy》2021,76(8):2535-2543