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91.
Left coronary artery compression syndrome is an uncommon entity and characterized by compression of the LMCA in-between the aorta and an enlarged main pulmonary arterial trunk. It is usually associated with a congenital cardiac defect. Cardiac 64-slice MDCT provides a non-invasive and an accurate method for assessing the degree of dynamic LMCA compression throughout the cardiac cycle, its angulation relative to the left sinus of Valsalva and depiction of pulmonary pathology, making it a valuable tool in the workup of patients suspected of left coronary artery compression.  相似文献   
92.
Most moving objects in the world are non-rigid, changing shape as they move. To disentangle shape changes from movements, computational models either fit shapes to combinations of basis shapes or motion trajectories to combinations of oscillations but are biologically unfeasible in their input requirements. Recent neural models parse shapes into stored examples, which are unlikely to exist for general shapes. We propose that extracting shape attributes, e.g., symmetry, facilitates veridical perception of non-rigid motion. In a new method, identical dots were moved in and out along invisible spokes, to simulate the rotation of dynamically and randomly distorting shapes. Discrimination of rotation direction measured as a function of non-rigidity was 90% as efficient as the optimal Bayesian rotation decoder and ruled out models based on combining the strongest local motions. Remarkably, for non-rigid symmetric shapes, observers outperformed the Bayesian model when perceived rotation could correspond only to rotation of global symmetry, i.e., when tracking of shape contours or local features was uninformative. That extracted symmetry can drive perceived motion suggests that shape attributes may provide links across the dorsal-ventral separation between motion and shape processing. Consequently, the perception of non-rigid object motion could be based on representations that highlight global shape attributes.  相似文献   
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Four clinically healthy dogs of either sex, aged 3–5 years, weighing between 9 and 18 kg and maintained under uniform management conditions, were administered haloperidol (5 mg/ml) and ketamine (50 mg/ml) intravenously in 1:1 ratio until the pedal reflex was lost. The calculated doses of haloperidol and ketamine were 1.71 and 17.05 mg/kg body weight intravenously, respectively. Corneal and palpebral reflexes were maintained although pain reflexes were absent up to 20 min of the cocktail administration. The induction of anaesthesia was quick and smooth. There was moderate to good muscle relaxation and analgesia. Mean arterial and central venous pressures and tidal volume decreased significantly (P < 0.05) from baseline values. Significant tachycardia and hyperglycemia were observed.  相似文献   
95.
Purpose:To report the association of procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) mutations with bilateral primary congenital glaucoma (PCG) in monozygotic twins and with nondominant juvenile-onset primary open-angle glaucoma (JOAG).Methods:We utilized family-based whole-exome sequencing to detect disease-causing mutations in a pair of monozygotic twins with de-novo PCG and compared its existence in 50 nonfamilial cases of JOAG and 30 healthy controls. To validate the identified mutations, direct Sanger sequencing was performed. For further evaluation of gene expression in the ocular tissues, we performed whole-mount in situ hybridization in zebrafish embryos.Results:We identified a novel missense mutation (c.1925A>G, p.Tyr642Cys) in the PLOD2 gene in the monozygotic twin pair with PCG and another missense mutation (c.1880G>A, p.Arg627Gln) in one JOAG patient. Both mutations identified were heterozygous. Neither the parents of the twins nor the parents of the JOAG patient harbored the mutation and it was probably a de-novo change. The zebrafish in situ hybridization revealed expression of the PLOD2 gene during embryogenesis of the eye.Conclusion:We observed an association of PLOD2 mutations with PCG and with nonfamilial JOAG. This new gene needs to be further investigated for its role in pathways associated with glaucoma pathogenesis.  相似文献   
96.
BackgroundImmune dysregulation plays a key role in determining COVID-19 disease severity. We aimed to analyze the T cell activation profile in COVID − 19 cases and its predictive role in disease severity and outcome.Material & methodsThis was a prospective observational pilot study from a tertiary care COVID-19 hospital. Peripheral blood samples obtained between the fifth and seventh day of COVID-19 illness, were subjected to lymphocyte subset analysis using multicolor flowcytometry using a single tube, 8 antibodies (CD45, CD19, CD3, CD4, CD8, CD38, HLADR, and CD56) analysis. Correlation between lymphocyte subset analysis and clinical profile was determined.Results26 patients including 11 with mild disease and 15 with severe disease were enrolled. The median age was 58 years (range: 33–81), with a male: female ratio of 1.36:1. Significant lymphopenia was observed in the severe group compared to the mild group (p < 0.02). The absolute numbers of CD3+, CD4+, CD8 + T cells, B cells, and NK cells were significantly reduced in the severe group as compared to the mild group (p < 0.05). In patients with severe disease, the proportion of CD8 + and CD4 + T cells were significantly higher than those in patients with mild disease (p = 0.0372). Using ROC analysis, a CD4:8 T cell ratio of ≥ 2.63 and an activated (CD38 + HLA-DR+) CD8 T cell proportion of > 15.85% of the total CD8 T cell population, significantly determined the severe disease category.ConclusionsSevere COVID-19 is associated with severe lymphopenia, altered CD4/CD8 ratio and markedly increased CD8 T cell activation profile.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12288-022-01558-6.  相似文献   
97.
98.
Intermaxillary fixation (IMF) is required before plating to achieve premorbid relationship of mandibular and maxillary teeth. We recommended the use of single wire for achieving IMF using 24 gauze stainless steel wire, which is an easy, fast, economical and minimally invasive technique.  相似文献   
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100.
Sobti  R.C.; Bhardwaj  D.K. 《Mutagenesis》1993,8(2):101-103
A cytogenetic survey was conducted on personnel exposed to petroleumexhaust fumes (vapour and smoke at automobile workshops). Theincidence of chromosomal aberrations (CAs) in this populationwas evaluated. A total of 1.15 ± 0.22 aberrations wereencountered in the exposed group as compared with 0.47 ±0.12 aberrations in the age matched controls. The increase inCAs in the exposed group was highly significant (P < 0.01,test of variance). A strongly positive correlation between increasingexposure duration and a higher incidence of CAs was apparent.No stratification for a higher incidence of CAs on the basisof smoking and/or alcoholic habits could be made in the exposedgroup.  相似文献   
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