451
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Soumekh M, Choi JH. Phase and amplitude phase restoration in synthetic aperture radar imaging. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1992; 1:229-242. [PMID: 18296157 DOI: 10.1109/83.136599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Methods for addressing two types of multiplicative noise in synthetic aperture radar (SAR) imaging are presented. The authors consider a multiplicative noise with a real phase (i.e. the SAR signal's phase is contaminated but its amplitude is uncorrupted) that possesses unknown functional characteristics with respect to the radar signal's temporal frequencies. A perturbation solution for phase reconstruction from amplitude is developed from a wave equation governing the SAR signal and a Riccati equation that relates the amplitude and phase functions of the SAR signal. This solution is converted into a noniterative analytical solution in terms of the moments and powers of the log amplitude function. Next, the authors consider a multiplicative noise with a complex phase (i.e. both the amplitude and phase of the SAR signal are contaminated) that varies linearly with respect to the radar signal's temporal frequencies. The two wave equations governing the SAR signal at two temporal frequencies of the radar signal are combined to derive a method to reconstruct the complex phase error function.
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452
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Suen KL, Choi JH. Isolation and sequence analysis of a cDNA clone for a carrot calcium-dependent protein kinase: homology to calcium/calmodulin-dependent protein kinases and to calmodulin. PLANT MOLECULAR BIOLOGY 1991; 17:581-590. [PMID: 1912486 DOI: 10.1007/bf00037045] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Recently, a novel type of calcium-dependent protein kinase (CDPK) that requires neither calmodulin nor phospholipids for activation, has been described in plants. We have isolated a cDNA clone for carrot CDPK by probing a library of somatic embryo cDNAs with oligonucleotides corresponding to highly conserved regions of protein kinases. The product of this gene overexpressed in Escherichia coli reacted strongly with monoclonal antibodies to soybean CDPK. The deduced amino acid sequence of carrot CDPK reveals two major functional domains. An N-terminal catalytic domain with greatest homology to calcium/calmodulin-dependent protein kinase type II from rat brain is coupled to a C-terminal calcium-binding domain resembling calmodulin. These features of the primary sequence explain how CDPK binds calcium and suggest a model for CDPK regulation based on similarities to animal calcium/calmodulin-dependent protein kinases.
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453
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Abstract
Cysticercosis, which has a worldwide distribution is found in man, who is usually infected by eating inadequately cooked pork or other contaminated food. Cysticercosis develops most commonly in the muscles and brain. Pulmonary involvement is very rare and also difficult to recognize because pulmonary lesions caused by the presence of cysticerci are difficult to discern from pulmonary infiltrates, because other parasitic infestations or tuberculosis, as well as metastatic lesions, produce similar chest X-ray findings and similar clinical symptoms. We experienced a case of pulmonary cysticercosis confirmed at Gyeongsang National University Hospital by means of an open lung biopsy and treated successfully with praziquantel (50 mg/kg per day for 15 days). This case seems to indicate that pulmonary cysticercosis should be considered as a diagnostic possibility in patients with nodular infiltrates in the lungs, especially in endemic areas, until such infiltrates are otherwise explained.
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454
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Hammerman C, Aramburo MJ, Choi JH. Prostanoid inhibition and group B hemolytic streptococci (GBS) induced neutropenia in newborn piglets. Prostaglandins Leukot Essent Fatty Acids 1990; 41:125-30. [PMID: 2125731 DOI: 10.1016/0952-3278(90)90065-s] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
GBS (Group B Hemolytic Streptococci) cause pulmonary hypertension with associated neutropenia. We investigated whether there is a correlation between the neutropenia of sepsis and GBS-induced pulmonary vasoconstriction, through study of the effects of inhibiting pulmonary vasoconstriction on the neutropenia of GBS in newborn piglets. Fifteen piglets were infused with GBS. After one hour, animals were given either a thromboxane inhibitor (DAZ), a combined cyclooxygenase/lipoxygenase inhibitor, BW755C, or placebo. With GBS infusion, WBC and PMN counts dropped steadily, from similar baselines, to 2250 +/- 570, 3300 +/- 500 and 5400 +/- 1100 cells/mm3 respectively (p less than 0.05; DAZ and BW vs. placebo). PMN's dropped similarly to 710 +/- 320, 2390 + 1240 and 3130 +/- 1050 cells/mm3 respectively (p less than 0.05; DAZ vs. BW and placebo). The drop in WBC's predominantly resulted from proportional decreases in PMN's (DAZ: r = 0.98; BW: r = 0.88; placebo r = 0.93). Compared to GBS alone, DAZ reduced pulmonary vasoconstriction, but exacerbated the granulocytopenia. BW755C similarly reduced pulmonary hypertension: however, it ameliorated the exacerbation of GBS induced neutropenia described above. These data imply that there is no direct correlation between GBS induced granulocytopenia and pulmonary hypertension.
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455
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Rogers C, Dowell S, Choi JH, Sathyavagiswaran L. Crossbow injuries. J Forensic Sci 1990; 35:886-90. [PMID: 2391480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The crossbow is an uncommon source of fatal injury. In Los Angeles County, two crossbow homicides have occurred in the past 20 years. Following the second case, a crossbow was test-fired into a fresh pork thigh, resulting in distinctive wounds. Experimental studies also showed that the vanes of the bolt (arrow) may be a source of trace material found in the wound.
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456
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Choi JH, Kornblum RN. Pete Maravich's incredible heart. J Forensic Sci 1990; 35:981-6. [PMID: 2202775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Postmortem examination of a former professional basketball player revealed an abnormal heart, most notably a single coronary artery. The literature on single coronary arteries is briefly reviewed, and the possible mechanism which caused the patient's condition is considered. This case is particularly unusual because of the patient's profession, which is so physically demanding.
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457
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Choi JH, Kim JK. Higher-genus characters for the level-two SU(2) WZW model and GKO coset construction. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1990; 41:1908-1913. [PMID: 10012563 DOI: 10.1103/physrevd.41.1908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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458
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Choi JH, Kim JK. Higher-genus characters of the Ising model. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1990; 41:484-491. [PMID: 10012355 DOI: 10.1103/physrevd.41.484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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459
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Yu BP, Lee DW, Marler CG, Choi JH. Mechanism of food restriction: protection of cellular homeostasis. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 1990; 193:13-5. [PMID: 2152977 DOI: 10.3181/00379727-193-42982] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The major difficulty in defining the mechanisms for the action of food restriction relates to its diversity and lack of specificity. In searching for the common factor(s) and commonality involved in such diversified effects, a cellular homeostasis mechanism is proposed. A study initiated in our laboratory strongly indicates that the cellular homeostatic mechanism is seriously compromised by oxidative damage of free radical reaction with aging. Data on mitochondrial hydroperoxide, microsomal cytochrome P-450 breakdown, and reduction of cytosolic antioxidant capacity support the notion. Remarkably, food restriction attenuates all of these age-related changes. It is concluded therefore that food restriction preserves the homeostatic regulatory processes by maintaining the integrity of (i) membrane structure and function, (ii) proper redox state of cellular components, and (iii) detoxification process of xenobiotics.
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460
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Choi DH, Choi JH, Whang SK, Kim YS. Regulation of acetyl CoA carboxylase mRNA in rat liver by high carbohydrate diet and insulin. Yonsei Med J 1989; 30:235-45. [PMID: 2573976 DOI: 10.3349/ymj.1989.30.3.235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Acetyl CoA carboxylase contents in liver cytosol of rats refed a high carbohydrate diet or injected with insulin were measured by an immunoassay method in order to evaluate the effects of dietary carbohydrate and insulin treatment on the control in the amount of acetyl CoA carboxylase. Acetyl CoA carboxylase was purified 1,552 folds with a specific activity of 3.88 units/mg protein from livers of rats refed a high carbohydrate diet for 3 days following a 3-day fasting and the antibody was generated against the purified acetyl CoA carboxylase in a rabbit. Treatment of insulin (1.5 units/100g BW) and a high carbohydrate diet increased the amount of acetyl CoA carboxylase in liver cytosol by 3 times and 10 times, respectively, when compared to the enzyme content found in the control. The synthetic ratio of acetyl CoA carboxylase to total cytosolic proteins was 4 times higher in the insulin-treated group and 10 times higher in the high carbohydrated diet-treated group than the control group. The polysomal RNA contents in liver cytosols were 279% of the control in the insulin-treated group and 365% of the control in the high carbohydrate diet group. Also, the nascent chain of acetyl CoA carboxylase in polysome were 158% of the control in the insulin-treated group and 311% of the control in the high carbohydrate treated group. From these results, it is assumed that the increase of acetyl CoA carboxylase content in the rat liver cells by insulin treatment, or high carbohydrate diet refeeding has resulted from the increased polysomal acetyl CoA carboxylase mRNA, which is directly related to the biosynthesis of this enzyme.
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461
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Choi JH, Koh IG. Erratum: Genus-two characters of the Ising model. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1989; 40:1371. [PMID: 10011953 DOI: 10.1103/physrevd.40.1371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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462
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Choi JH, Koh IG. Genus-two characters of the Ising model. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1989; 39:3163-3166. [PMID: 9959553 DOI: 10.1103/physrevd.39.3163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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463
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Hammerman C, Yousefzadeh D, Choi JH, Bui KC. Persistent pulmonary hypertension of the newborn. Managing the unmanageable? Clin Perinatol 1989; 16:137-56. [PMID: 2656058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Persistent pulmonary hypertension of the newborn is a complex syndrome with multiple causes, which retains a high morbidity and mortality. This article presents pathophysiologic and diagnostic foundations and then focuses the discussion on management issues.
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464
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Hammerman C, Aramburo MJ, Choi JH. Prostaglandin E1 selectively reduces group B beta-hemolytic streptococci-induced pulmonary hypertension in newborn piglets. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1989; 143:343-7. [PMID: 2492755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Group B beta-hemolytic streptococci (GBS)-induced pulmonary hypertension was generated in ten newborn piglets. Intravenous infusions of either prostaglandin E1 (PGE1) (n = 5) or placebo (n = 5) were begun after 60 minutes of stable pulmonary hypertension. The effects of these interventions on cardiopulmonary hemodynamics were studied. Pulmonary artery pressure (PAP) increased similarly in both groups during the first 60 minutes of GBS infusion. By two hours after intervention, PAP was significantly lower in the animals given PGE1 (20 +/- 4 vs 32 +/- 5 mm Hg for PGE1 vs placebo). The ratio of pulmonary to systemic vascular resistance followed a pattern analogous to PAP, increasing with the GBS infusion, indicating selective pulmonary vasoconstriction. The pulmonary vascular resistance/systemic vascular resistance ratio decreased after intervention in the group given PGE1 only (0.25 +/- 0.08 vs 0.50 +/- 0.12 for PGE1 vs placebo), indicating selective pulmonary vasodilation. Transient systemic hypotension was noted at one hour after initiation of PGE1 infusion. Prostaglandin E1 infusion selectively improved GBS-induced pulmonary hypertension and hypoxemia in newborn piglets with only transient systemic hypotension.
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465
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Soumekh M, Choi JH. Reconstruction in diffraction imaging. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 1989; 36:93-100. [PMID: 18284954 DOI: 10.1109/58.16973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The problem of reconstruction in imaging systems that are modeled using the Helmholtz wave equation (diffraction imaging) is addressed. A spectral analysis of the available diffraction data is presented to help develop algorithms and constraints on a diffraction imaging system's parameters for accurate reconstruction of the desired image. Means of reducing the execution time of these algorithms and their relationship to currently available filtered backpropagation and unified Fourier reconstruction methods are also discussed.
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466
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Moon HR, Ko TS, Ko YY, Choi JH, Kim YC. Cystic fibrosis--a case presented with recurrent bronchiolitis in infancy in a Korean male infant. J Korean Med Sci 1988; 3:157-62. [PMID: 3267364 PMCID: PMC3053675 DOI: 10.3346/jkms.1988.3.4.157] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The aim of this case report is to draw the attention to the occurrence of cystic fibrosis (C.F.) in a Korean infant and thus increase the awareness for the diagnosis. The male infant was presented with a history of recurrent bronchiolitis manifested by severe cough, wheeze and dyspnea from three weeks of age, in whom the diagnosis of C.F. was clinically suspected and was confirmed by demonstration of two elevated sweat chloride levels (97 mEq/L and 99 mEq/L) in the patient. The diagnosis was delayed because the main manifestations of C.F. were the same as the main symptoms of common diseases such as cough, diarrhea and failure to thrive. C.F. is probably underdiagnosed in Korean population both because the diagnosis is not considered since the disease is thought to be uncommon or even not to occur and because diagnostic facilities including the quantitative iontophoresis sweat test are lacking.
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467
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Rao N, Smith RE, Choi JH, Xu XH, Kornblum RN. Autopsy findings in the eyes of fourteen fatally abused children. Forensic Sci Int 1988; 39:293-9. [PMID: 3229710 DOI: 10.1016/0379-0738(88)90133-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The eyes of fourteen fatally abused children and sixteen control cases were examined histopathologically. Ten of the abused children showed intraocular change. The most common ocular changes were subdural hemorrhage of the optic nerve and retinal hemorrhage which involved all the layers of the retina, but most commonly the nerve fiber layer, ganglion cell layer and inner nuclear layer. The presence of blood cavities within the retina partially supported the hypothesis of traumatic retinoschisis. The control cases of non-abused children rarely showed intraocular hemorrhage.
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468
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469
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Choi JH, Ryu KS. Responses of broilers to dietary zinc bacitracin at two different planes of nutrition. Br Poult Sci 1987; 28:113-8. [PMID: 3567680 DOI: 10.1080/00071668708416942] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Four concentrations of Zn bacitracin (0, 50, 100 and 150 mg/kg) added to diets of two different planes of nutrition were fed to male broiler chicks for 7 weeks. Feeding broilers Zn bacitracin significantly improved growth rate and food conversion, and increased shank pigmentation. The effects of Zn bacitracin were independent of the plane of nutrition. Regression analyses revealed that the responses of birds were linear.
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470
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Borkird C, Choi JH, Sung ZR. Effect of 2,4-dichlorophenoxyacetic Acid on the expression of embryogenic program in carrot. PLANT PHYSIOLOGY 1986; 81:1143-6. [PMID: 16664958 PMCID: PMC1075500 DOI: 10.1104/pp.81.4.1143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Embryogenesis in a wild carrot cell line, W001C, can start and progress up to the first morphogenetic stage (the globular-stage embryo) in 2,4-dichloropenoxyacetic acid (2,4-D). To clarify the quantitative effect of 2,4-D on this cell line, morphological and biochemical criteria have been used to monitor embryogenesis in the presence of increasing concentrations of 2,4-D. The biochemical criteria are the ability to inactivate cycloheximide and the expression of an embryogenic polypeptide E(1). The results show that 2,4-D can affect embryogenesis in a quantitative manner but never fully suppresses embryogenesis unless it is coupled with high cell density.
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471
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Choi JH, So BS, Ryu KS, Kang SL. Effects of pelleted or crumbled diets on the performance and the development of the digestive organs of broilers. Poult Sci 1986; 65:594-7. [PMID: 3703802 DOI: 10.3382/ps.0650594] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Two types (mash and crumble) of the starter ration (for 0 to 4 weeks of age) and two types (mash and pellets) of the finisher ration (for 4 to 8 weeks of age) were fed to broilers in a 2 X 2 factorial arrangement. Chicks fed the crumbled starter diet gained more weight and consumed more feed (P less than .01). Pelleting the finisher diet also significantly (P less than .01) improved weight gain and feed intake. Feeding the crumble during the starter period significantly (P less than .05) decreased gizzard weight at 4 weeks of age. Pelleting the finisher diet also significantly (P less than .01) reduced weights of the digestive tract and the gizzard at 8 weeks of age, compared to those fed the mash diet.
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472
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Abstract
Strangulation accounts for up to 10% of violent or criminally related deaths in the United States annually. Strangulation techniques include hanging, throttling, garrotting, and chokeholds. These methods are thought to cause unconsciousness or death by compression of either the airway or the major vessels of the neck. A review of the records of 112 nonsurvivors and 59 survivors of strangulation revealed that hyoid bone and laryngotracheal fractures occurred in both groups, particularly in throttling victims. The laryngeal injuries themselves could not be implicated as the cause of death, and survivors usually presented without airway compromise. However, failure to appreciate such injuries in survivors may lead to permanent voice complications. A full understanding of the spectrum of strangulation is also required if the otolaryngologist is called to testify as an expert witness in such cases.
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473
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Haust MD, Gordon BA, Hong R, Choi JH, Langer LO, Spranger J, Opitz JM. Clinicopathological conference: an adolescent girl with severe mental impairment and mucopolysacchariduria. AMERICAN JOURNAL OF MEDICAL GENETICS 1985; 22:1-27. [PMID: 2931979 DOI: 10.1002/ajmg.1320220102] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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474
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Thorson WR, Choi JH, Knudson SK. Novel theory of the HD dipole moment. I. Theory. PHYSICAL REVIEW. A, GENERAL PHYSICS 1985; 31:22-33. [PMID: 9895449 DOI: 10.1103/physreva.31.22] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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475
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Thorson WR, Choi JH, Knudson SK. Novel theory of the HD dipole moment. II. Computations. PHYSICAL REVIEW. A, GENERAL PHYSICS 1985; 31:34-42. [PMID: 9895450 DOI: 10.1103/physreva.31.34] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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