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991.
992.
Breast implant capsules are a foreign body immune response to breast implants. It has been proposed that capsulectomy after breast implant removal was unnecessary, as the body resorbs the capsule when the implant, the impetus for the foreign body response, is removed. We report eight women with persistent capsules 10 months to 17 years after silicone breast implant removal. 相似文献
993.
CA Smith 《Canadian Metallurgical Quarterly》1997,42(4):334-346
This study uses lifespan and ecological frameworks to investigate the factors associated with early adolescent sexual activity. Data from a longitudinal study of urban teenagers of color address three issues: (1) the prevalence and pattern of sexual activity among boys and girls ages 15 and younger, (2) the link between early sexual activity and high-risk sexual behavior, and (3) the life contexts linked with early sexual activity. Results from 803 African American and Hispanic adolescents suggest a high prevalence of early sexual activity, which is associated with higher rates of childbearing and risky sexual behavior than sexual activity initiated in later adolescence. Somewhat different factors are associated with early sexual activity for boys and girls, although family composition, parent attachment, and substance use are important for both genders. Implications for intervention are discussed. 相似文献
994.
SP Kantrow DE Taylor MS Carraway CA Piantadosi 《Canadian Metallurgical Quarterly》1997,345(2):278-288
We hypothesized that cellular oxygen consumption is abnormal during sepsis as a result of increased oxidative stress and selective mitochondrial damage. In a rat model of sepsis (cecal ligation and puncture), we studied the respiratory characteristics of isolated hepatocytes and liver mitochondria 16 h after onset of septic injury. Endogenous respiration by isolated cells was decreased during sepsis, while cyanide-resistant (nonmitochondrial) respiration was unaffected. Maximal oxygen consumption in ADP-supplemented, permeabilized hepatocytes was decreased with succinate as the substrate, but not with malate + glutamate or TMPD + ascorbate. In contrast, maximum oxygen consumption (State 3) by isolated liver mitochondria increased up to 35% during sepsis using either succinate or malate + glutamate as substrate. The electrophoretic features and mobility of nondenatured mitochondrial respiratory complexes were similar in control and septic hepatocytes, with the exception of decreased Complex V protein in sepsis. Structural evaluation of mitochondria in fixed liver slices by electron microscopy showed mitochondrial swelling in most of the septic animals. Measurements of oxidative stress during sepsis suggested an increase in hydroxylation of salicylate by isolated hepatocytes, and mitochondrial protein carbonyl content was increased significantly. Induction of iNOS in hepatocytes after 16 h of sepsis was variable, and little release of the oxidation products of NO. was detected. These findings are interpreted to mean that hepatocytes contain a mixed population of injured and hyperfunctional mitochondria during sepsis. 相似文献
995.
YL Cao E Lach TH Kim A Rodríguez CA Arévalo CA Vacanti 《Canadian Metallurgical Quarterly》1998,102(7):2293-2298
We describe a simple, effective approach to the creation of autologous tissue-engineered cartilage in the shape of a human nipple by injecting a reverse thermosensitive polymer seeded with autologous chondrocytes in an immunocompetent porcine animal model. A biodegradable, biocompatible copolymer of polyethylene oxide and polypropylene oxide (Pluronic F-127), which exists as a liquid below 4 degrees C and polymerizes to a thick gel when it is exposed to physiologic temperatures (body temperatures), was used as a vehicle for chondrocyte delivery and as a scaffold to guide growth. Autologous chondrocytes isolated from porcine auricular elastic cartilage and suspended in 30% (weight/volume) Pluronic F-127 were injected on the ventral surface of the pigs from which the cells had been isolated. A circumferential subdermal suture was used to support the contour of the implant and assist in its projection in the form of a human nipple. After 3 weeks, the skin over and surrounding the implant was tattooed to create the appearance of a human nipple-areolar complex. As controls, an equal number of injections were made using either cells alone (not suspended in hydrogel), or hydrogel alone. After 10 weeks, all specimens were excised and examined both grossly and histologically. Before harvesting, visual inspection of the tattooed chondrocyte-Pluronic F-127 hydrogel implant sites revealed that they closely resembled a human female nipple-areolar complex. Nodules were similar in size, shape, and texture to a human nipple at each injection site. Glistening opalescent tissue was surgically isolated from each implant site. Hematoxylin and eosin, safranine o, trichrome blue, and Verhoeff's stains of the experimental implants showed nodules with the characteristic histologic signs of elastic cartilage. Control injections of copolymer hydrogel alone exhibited no evidence of cartilage formation. Control injections of chondrocytes alone showed evidence of dissociated microscopic nodules of elastic cartilage. 相似文献
996.
SC Kaste KP Hopkins D Jones D Crom CA Greenwald VM Santana 《Canadian Metallurgical Quarterly》1997,11(6):792-796
The purpose of this study was to define the therapy-associated dental abnormalities in survivors of acute lymphoblastic leukemia (ALL). We reviewed the clinical records and panoramic radiographs of 423 survivors of ALL who were treated on one of four consecutive protocols (1975-1991). Dental abnormalities included root stunting, microdontia, hypodontia, taurodontia (enlarged pulp chambers), and over-retention of primary teeth. The frequency of these factors was determined in relation to age at initiation of treatment (< or = 8 years vs > 8 years), addition of cranial irradiation, and chemotherapeutic protocol. A total of 423 patients met the study criteria. The abnormalities comprised root stunting in 24.4% (n = 103), microdontia in 18.9% (n = 80), hypodontia in 8.5% (n = 36), taurodontia in 5.9% (n = 25), and over-retention of primary dentition in 4.0% (n = 17). Patients who were < or = 8 years old at diagnosis or who received cranial irradiation therapy developed more dental abnormalities than did those > 8 years and those who did not receive cranial irradiation (42 vs 32%). Survivors of childhood ALL often have dental abnormalities that may affect their quality of life. Dental evaluation at diagnosis and frequent follow-up may help to ensure appropriate preventive measures and minimize dental and periodontal disease. 相似文献
997.
CP Heneghan CA Harrison 《Canadian Metallurgical Quarterly》1998,53(7):711; author reply 711-711; author reply 712
998.
A questionnaire was sent to all general practitioners (GPs) in Cambridgeshire asking them about their practice in telling patients with dementia or terminal cancer their diagnosis. Although the majority of GPs would always or often tell patients of a diagnosis of terminal cancer, this was not the case in dementia; uncertainty of diagnosis was cited as the most important factor in not giving the diagnosis. The implications of these findings are discussed in the light of the GP's role in dementia and the development of new anti-Alzheimer's drugs. 相似文献
999.
CA Stockmeier LA Shapiro GE Dilley TN Kolli L Friedman G Rajkowska 《Canadian Metallurgical Quarterly》1998,18(18):7394-7401
It has been hypothesized that a deficit in serotonin may be a crucial determinant in the pathophysiology of major depression. Serotonin-1A receptors are located on serotonin cell bodies in the midbrain dorsal raphe (DR) nucleus, and the activation of these receptors inhibits the firing of serotonin neurons and diminishes the release of this neurotransmitter in the prefrontal cortex. Repeated treatment with some antidepressant medications desensitizes serotonin-1A receptors in the rat midbrain. The present study determined whether the binding of [3H]8-hydroxy-2-(di-n-propyl)aminotetralin (8-OH-DPAT), an agonist at serotonin-1A receptors, is altered in the midbrain of suicide victims with major depression. Radiolabeling of the serotonin-1A receptor in the DR varied significantly along the rostral-to-caudal extent of the human midbrain. The binding of [3H]8-OH-DPAT to serotonin-1A receptors was increased significantly in the midbrain DR of suicide victims with major depression as compared with psychiatrically normal control subjects. In suicide victims with major depression, the increase in the binding of [3H]8-OH-DPAT to serotonin-1A receptors was detected in the entire DR and specifically localized to the dorsal and ventrolateral subnuclei. Enhanced radioligand binding of an agonist to inhibitory serotonin-1A autoreceptors in the human DR provides pharmacological evidence to support the hypothesis of diminished activity of serotonin neurons in suicide victims with major depression. 相似文献
1000.
DA Theodoro GK Danielson CJ Porter CA Warnes 《Canadian Metallurgical Quarterly》1998,65(1):149-53; discussion 153-4
BACKGROUND: Atrial fibrillation and flutter, commonly associated with congenital heart anomalies that cause right atrial dilatation, may cause significant morbidity and reduction of quality of life, even after surgical repair of the anomalies. METHODS: In an effort to reduce the incidence of atrial tachyarrhythmias after repair of right-sided congenital heart disease, we performed a concomitant right-sided maze procedure. RESULTS: Eighteen patients with paroxysmal atrial fibrillation or flutter (n = 12) or chronic atrial fibrillation or flutter (n = 6) aged 10.9 to 68.4 years (mean 34.9 years) underwent a right-sided maze in association with repair of Ebstein's anomaly (n = 15), congenital tricuspid insufficiency (n = 2), and isolated atrial septal defect (n = 1). There were no early deaths, reoperations, or complete heart block. Discharge rhythm was sinus (n = 16) or junctional (n = 2). Follow-up was complete in all 18 patients and ranged from 3.1 to 17.2 months (mean 8.1 months); all are in New York Heart Association class I. Early postoperative arrhythmias developed in 3 patients (all were converted to sinus rhythm by antiarrhythmic drugs). There were no late deaths or reoperations. CONCLUSIONS: The inclusion of a right-sided maze procedure with cardiac repair in patients having congenital heart anomalies that cause right atrial dilatation and associated atrial tachyarrhythmias is effective in eliminating or reducing the incidence of those arrhythmias. 相似文献