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BackgroundThe US physician workforce does not represent the racial or ethnic diversity of the population it serves.ObjectivesTo assess whether the proportion of US physician trainees of Black race and Hispanic ethnicity has changed over time and then provide a conceptual projection of future trends.DesignCross-sectional, retrospective, analysis based on 11 years of publicly available data paired with recent US census population estimates.ParticipantsA total of 86,303 (2007–2008) to 103,539 (2017–2018) resident physicians in the 20 largest US Accreditation Council for Graduate Medical Education resident specialties.Main MeasuresChanges in proportion of physician trainees of Black race and Hispanic ethnicity per academic year. Projected number of years it will then take, for specialties with positive changes, to reach proportions of Black race and Hispanic ethnicity comparable to that of the US population.Key ResultsAmong the 20 largest specialty training programs, Radiology was the only specialty with a statistically significant increase in the proportion of Black trainees, but it could take Radiology 77 years to reach levels of Black representation comparable to that of the US population. Obstetrics/Gynecology, Emergency Medicine, Internal Medicine/Pediatrics, and Orthopedic Surgery demonstrated a statistically significant increase in the proportion of Hispanic trainees, but it could take these specialties 35, 54, 61, and 93 years respectively to achieve Hispanic representation comparable to that of the US population.ConclusionsAmong US residents in the 20 largest specialties, no specialty represented either the Black or Hispanic populations in proportions comparable to the overall US population. Only a small number of specialties demonstrated statistically significant increases. This conceptual projection suggests that current efforts to promote diversity are insufficient.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06650-7.Key Words: Accreditation Council for Graduate Medical Education, physician workforce, workforce diversity  相似文献   
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Background

Aim of the study was to find out which myocardial repolarization parameters predict reperfusion ventricular tachycardia and fibrillation (VT/VF) and determine how these parameters express in ECG.

Methods

Coronary occlusion and reperfusion (30/30 min) was induced in 24 cats. Local activation and end of repolarization times (RT) were measured in 88 intramyocardial leads. Computer simulations of precordial electrograms were performed.

Results

Reperfusion VT/VF developed in 10 animals. Arrhythmia-susceptible animals had longer RTs in perfused areas [183(177;202) vs 154(140;170) ms in susceptible and resistant animals, respectively, P < 0.05]. In logistic regression analysis, VT/VFs were associated with prolonged RTs in the perfused area (OR 1.068; 95% CI 1.012–1.128; P = 0.017). Simulations demonstrated that prolonged repolarization in the perfused/border zone caused precordial terminal T-wave inversion.

Conclusions

The reperfusion VT/VFs were independently predicted by the longer RT in the perfused zone, which was reflected in the terminal negative phase of the electrocardiographic T-wave.  相似文献   
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The role of fast activity as a potential biomarker in localization of the epileptogenic zone (EZ) remains controversial due to recently reported unsatisfactory performance. We recently identified a “fingerprint” of the EZ as a time‐frequency pattern that is defined by a combination of preictal spike(s), fast oscillatory activity, and concurrent suppression of lower frequencies. Here we examine the generalizability of the fingerprint in application to an independent series of patients (11 seizure‐free and 13 non‐seizure‐free after surgery) and show that the fingerprint can also be identified in seizures with lower frequency (such as beta) oscillatory activity. In the seizure‐free group, only 5 of 47 identified EZ contacts were outside the resection. In contrast, in the non‐seizure‐free group, 104 of 142 identified EZ contacts were outside the resection. We integrated the fingerprint prediction with the subject's MR images, thus providing individualized anatomical estimates of the EZ. We show that these fingerprint‐based estimates in seizure‐free patients are almost always inside the resection. On the other hand, for a large fraction of the nonseizure‐free patients the estimated EZ was not well localized and was partially or completely outside the resection, which may explain surgical failure in such cases. We also show that when mapping fast activity alone onto MR images, the EZ was often over‐estimated, indicating a reduced discriminative ability for fast activity relative to the full fingerprint for localization of the EZ.  相似文献   
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Brain tumors are the common site for solid tumors in childhood. Very few studies have investigated genes with low penetrance in relation to pediatric brain tumor (pBT) development. Brain tumors do occur more frequently in males compared to females regardless of age, tumor histology, or region of the world. Taken into account these facts, we have designed a study aimed to analyse the contribution of some genetic factors to pBP in males and females. Patients with glial and embryonic brain tumors (160 males, 124 females) and healthy controls (277 males, 187 females) were included in the study. All subjects were genotyped for eight polymorphic variants in the genes of xenobiotics detoxification CYP1A1 (rs2606345, rs4646903, rs1048943), GSTM1 (Ins/del), GSTT1 (Ins/del), repair ERCC2 (rs1799793, rs13181), and folate pathway MTHFR (rs1801133). Genotype-specific risks of pBT were sex-dependent. GSTM1 deletion and dual deletions in GSTM1-GSTT1 loci were associated with brain tumor in males (P?=?1.2?×?10?5; odds ratio (OR)?=?2.56; 95 % confidence interval (CI), 1.45–3.85 and P?=?4.9?×?10?4; OR?=?3.09; 95 % CI, 1.63–5.89, relatively). The increased risk of brain tumors was evident for CYP1A1 rs2606345 (P?=?0.0028; OR?=?2.06; 95 % CI, 1.27–3.34) and minor haplotypes rs2606345–rs1048943–rs4646903 in females (global haplotype association P value, 0.0011). This study provides first evidence for the different pronounced pBT associations in males and females. This phenomenon possibly reflects the sexual dimorphism as an important determinant of brain tumor biology.  相似文献   
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Abstract

The trial objective was to determine the peripheral blood NK cells cytotoxic activity effect on trophoblast cells at recurrent pregnancy loss (RPL). The investigation involved non-pregnant women with PRL in proliferating and secretory menstrual cycle phases (PMCPh and SMCPh, respectively); women of 6–7 weeks pregnancy with RPL in past medical history; healthy fertile non-pregnant women in PMCPh and SMCPh, women of 6–7 weeks physiological pregnancy, nulliparity healthy women with regular menstrual function in PMCPh and SMCPh. NK cells cytotoxic activity was determined using peripheral blood mononuclear cells. The target cells were JEG-3?line trophoblasts. It has been established that NK cells cytotoxic activity effect on trophoblasts is lower in SMCPh than in PMCPh in non-pregnant fertile women. The NK cells cytotoxic activity was higher in SMCPh than in PMCPh in non-pregnant women with PRL and also higher than the same value in SMCPh in non-pregnant fertile women. The increased NK cells cytotoxic activity values in SMCPh in women with RPL may be the reason for miscarriage.  相似文献   
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ABSTRACT

While the association between microbiomes and inflammatory bowel disease (IBD) is well known, establishing causal relationships between the two is difficult in humans. Germ-free (GF) mice genetically susceptible to IBD can address this question. Smad3-/- mice with defective transforming growth factor ß signaling are a model of IBD and colon cancer. They develop IBD upon colonization with Helicobacter under specific pathogen-free conditions, suggesting a role of the microbiome in IBD in this model. Thus, we rederived Smad3-/- mice GF to determine the potential of using these mice for testing the causative role of microbiomes in IBD. We found that fecal microbiomes from mice with IBD cause more severe gut inflammation in GF Smad3-/- and wild type mice compared to microbiomes from healthy mice and that Helicobacter induces gut inflammation within the context of other microbiomes but not by itself. Unexpectedly, GF Smad3+/+ and Smad3+/- mice given IBD microbiomes develop IBD despite their lack of disease in SPF conditions upon Helicobacter infection. This was not unique to the background strain of our Smad3 model (129); both wild type C57BL/6 and 129 strains developed IBD upon fecal transfer. However, wild type Swiss Webster stock was not susceptible, indicating that the genetic background of recipient mice influences the severity of IBD following fecal transfer. Our data suggest that the microbiome is an independent risk factor contributing to IBD development, and careful characterization of new GF models is needed to understand potential sources of confounding factors influencing microbiome studies in these mice.  相似文献   
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A method for magnesium scrap transformation into highly efficient hydroreactive material was elaborated. Tested samples were manufactured of magnesium scrap with no additives, or 5 and 10 wt.% Devarda’s alloy, by ball milling for 0.5, 1, 2, and 4 h. Their microstructural evolution and reaction kinetics in 3.5 wt.% NaCl solution were investigated. For the samples with additives and of scrap only, microstructural evolution included the formation of large plane-shaped pieces (0.5 and 1 h) with their further transformation into small compacted solid-shaped objects (2 and 4 h), along with accumulation of crystal lattice imperfections favoring pitting corrosion, and magnesium oxidation with residual oxygen under prolonged (4 h) ball milling, resulting in the lowest reactions rates. Modification with Devarda’s alloy accelerated microstructural evolution (during 0.5–1 h) and the creation of ‘microgalvanic cells’, enhancing magnesium galvanic corrosion with hydrogen evolution. The 1 h milled samples, with 5 wt.% Devarda’s alloy and without additives, provided the highest hydrogen yields of (95.36 ± 0.38)% and (91.12 ± 1.19)%; maximum reaction rates achieved 470.9 and 143.4 mL/g/min, respectively. Such high results were explained by the combination of the largest specific surface areas, accumulated lattice imperfections, and ‘microgalvanic cells’ (from additive). The optimal values were 1 h of milling and 5 wt.% of additive.  相似文献   
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