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1.
A rare case of a maxillo-mandibular band in a 21 year female patient is reported. Possibility of its being a remnant of buccaphary geal membrane is discussed in the light of clinical and histological findings. 相似文献
2.
Of 132 children with bladder stones seen in 1 year, 94% were boys and 73% were aged between 1 and 5 years. Significant malnutrition and evidence of vitamin deficiency were absent. Wheat bread was the dietary staple, while the intake of milk and dairy products, eggs and meat was very low. Analysis of 29 stones showed them to consist mainly of calcium oxalate and uric acid, with small amounts of calcium phosphate and magnesium ammonium phosphate in some cases. The composition of the surface and central parts of the stones, examined in 20 cases, was usually different. The nucleus was formed almost entirely of calcium oxalate and uric acid in four and three cases respectively, whereas the surface layers were composed of other ingredients. In another case the nucleus was composed entirely of xanthine, which indicated a diagnosis of xanthinuria. 相似文献
3.
4.
D C Holmes W R Grigsby V K Goel J C Keller 《The International journal of oral & maxillofacial implants》1992,7(4):450-458
Using the finite element method, this study modeled a 4.0 x 13.0-mm IMZ implant, restored with a cast gold crown, to examine the influence of the polyoxymethylene (POM) intramobile element (IME) on the transmission of vertical and oblique forces. Stress concentrations in the bone and in components of the implant system were much greater under a 30-degree load than under an equal vertical load. Stress transmission to bone occurred chiefly in the crestal region, and these stresses were not reduced when the IME was modeled in POM rather than in titanium. Maximum stress concentrations occurred in the fastening screw. 相似文献
5.
D P Muzumdar A Goel R Mistry S Gujral S Fattepurkar 《Journal of clinical neuroscience》2004,11(5):534-537
An 18-year old boy presented with a tumour involving a large part of the petrous bone. A radical resection of a petrous bone 'aneurysmal bone cyst' was achieved. A large defect in the dura adjoining the posterior surface of the petrous bone was made during surgery. Post-operative MR imaging showed complete tumour resection but herniation of cerebellum into the operative defect, a phenomenon probably assisting to seal the site of cerebrospinal fluid fistula. 相似文献
6.
Dynamic response of the occipito-atlanto-axial (C0-C1-C2) complex in right axial rotation. 总被引:2,自引:0,他引:2
H Chang L G Gilbertson V K Goel J M Winterbottom C R Clark A Patwardhan 《Journal of orthopaedic research》1992,10(3):446-453
The torque-angular deformation in right axial rotation until failure of the ligamentous occipito-atlanto-axial complex subjected to variable loading rate (dynamic) axial torque was characterized using a biaxial MTS system. A special fixture and gear box that permitted right axial rotation of the specimen until failure without imposing any additional constraints were used to obtain the data. The specimens were divided into three groups and tested until failure at three different dynamic loading rates: 50, 100, and 400 degrees/s. A previous study by the authors provided data for quasi-static (4 degrees/s) loading conditions. The torque versus rotation curves can be divided into two straight regions and two transition zones. The plots clearly indicated that at loading rates higher than 4 degrees/s, the specimens became stiffer in the region of steadily increasing resistance prior to failure. The increase in stiffness was maximum at 100 degrees/s. The stiffness decreased somewhat at 400 degrees/s in comparison with 100 degrees/s, but this decrease was not significant. The resulting torque-right axial rotation curves were also examined to estimate the magnitude of maximum resistance (torque) and the corresponding angular rotation value. The average maximum resistance torque increased from 13.6 Nm at 4 degrees/s to 27.8 Nm at 100 degrees/s. The corresponding right angular rotation data (65-78 degrees), however, did not show any significant variation with loading rate. Posttest dissection of the specimens indicated that the type of injury observed was related to the rate of axial loading imposed on a specimen during testing.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
To study the effects of electroconvulsive therapy (ECT) on hormone release, we measured circulating concentrations of adrenocorticotropic hormone (ACTH), prolactin (PRL), growth hormone (GH) and cortisol (CORT) immediately before and at 2 min, 5 min, 15 min, and 30 min following ECT. Compared to pre-ECT concentrations, there were significant increases in post-ECT plasma ACTH, PRL and CORT. GH did not change consistently. No significant difference between unilateral and bilateral ECT was observed. Compared to the first ECT, repeated treatments were associated with a significant decrease in the magnitude of hormone surge. These hormonal changes induced by ECT may reflect changes at the neurotransmitter level. 相似文献
8.
Toxic shock syndrome (TSS) in children 总被引:1,自引:0,他引:1
Toxic shock syndrome is uncommon in the prepubertal age group. Two children presented with pyrexia, macular erythroderma, vomiting, hypotension and rapid deterioration of consciousness. One child had severe neurological involvement. The diagnosis of toxic shock syndrome was established in both cases by the exclusion of other causes and by culturing staphylococcus aureus. We postulate that the neurological manifestations were caused by a direct neurotoxic action of the staphylococcal-produced toxin. Both children made a complete recovery. 相似文献
9.
Madhu Bala Harish Chandra Goel 《Journal of environmental pathology, toxicology and oncology》2004,23(2):139-144
Recent reports showed that whole extract of Podophyllum hexandrum was radioprotective in mice. Podophyllotoxin is one of the major constituents of the whole extract of Podophyllum. In this study we report on the radioprotective action of podophyllotoxin in Saccharomyces cerevisiae yeast. Proliferating yeast cells pretreated with podophyllotoxin (2.5-5.0 microg/mL) for > or =3 hours showed a higher surviving fraction after (60)Co-gamma-irradiation (200-600 Gy) than did the irradiated cells not pretreated with podophyllotoxin. The maximum increase (2.0 times) in surviving fraction was observed in cells treated with 2.5 microg/mL podophyllotoxin, 5 hours before (60)Co-gamma-irradiation (400 Gy). Podophyllotoxin was not mutagenic or recombinogenic at radioprotective doses (2.5 microg/mL). A post-irradiation decrease in revertants and gene convertants was observed in cells treated with podophyllotoxin (2.5 microg/mL podophyllotoxin, -5 hours, 400 Gy). This study indicates that podophyllotoxin is radioprotective in yeast, and its radioprotective effects in higher eukaryotes would be worth investigating. 相似文献
10.
Perla A Vargas Pippa M Simpson Margo Bushmiaer Rajiv Goel Craig A Jones James S Magee Charles R Feild Stacie M Jones 《Annals of allergy, asthma & immunology》2006,96(6):787-793
BACKGROUND: Children with poorly controlled asthma are at high risk of airway remodeling, sleep disruption, school absenteeism, and limited participation in activities. OBJECTIVE: To determine asthma prevalence and characterize disease severity and burden in school-aged children. METHOD: A case-finding study was conducted via a multiple-choice questionnaire and asthma algorithm. Items used for analysis include physician diagnosis of asthma, symptom severity, and health care utilization. The chi2 test was used to determine the significance of differences among cases. Logistic regression was used to evaluate the association of patient factors and asthma indicators. RESULTS: Of the 5,417 children surveyed, 1,341 (25%) were classified as being at risk of asthma. Of these asthma cases, 55% were positive by diagnosis and algorithm (active), 10% were positive per algorithm alone (suspected), and 35% were positive per diagnosis alone (nonactive). Only 14% of all asthma cases reported experiencing no respiratory symptoms (< 1% active, 2% suspected, and 40% nonactive) compared with 75% of noncases. Also, 75% of noncases reported never missing school compared with 19%, 33%, and 54% of active, suspected, and nonactive asthma cases. African American race, Medicaid enrollment, and male sex were independent predictors of asthma risk. Similarly, African American race, Medicaid enrollment, age, and persistent asthma were independent predictors of emergency department use among asthma cases. DISCUSSION: Prevalence of active symptoms suggestive of poor asthma control was extremely high among urban, minority children enrolled in Arkansas' largest public school district. Poor asthma control greatly affects quality of life, including school attendance and performance. Interventions should raise expectations and emphasize the importance of achieving asthma control. 相似文献