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91.
This study sought to determine whether persons of French-Canadian heritage in northern New England are at high risk for the lethal infantile form of Tay-Sachs disease. In order to accomplish this, death records and laboratory diagnostic records were surveyed to ascertain Tay-Sachs deaths in a cohort of 372,000 live births between 1977-1986. The proportion of the total population with French-Canadian or Jewish heritage was determined from census and birth records, and the ethnic background of Tay-Sachs cases was determined from the corresponding birth records. In 1,860 births, both parents were of Ashkenazi Jewish heritage. One of those children was diagnosed with Tay-Sachs disease. In 41,000 births, both parents were of French-Canadian heritage, and in an additional 93,000 births, one parent was of French-Canadian heritage. No cases of Tay-Sachs disease were identified in the offspring of those individuals. Approximately 14 cases (95% confidence interval 8-20) would be expected, if the gene frequency approximated that reported for individuals of Ashkenazi Jewish heritage. Based on the results of this study, routine testing for Tay-Sachs disease heterozygosity is not indicated for persons of French-Canadian heritage in northern New England. This conclusion may not necessarily be valid for persons of French-Canadian heritage residing in other states. Further studies of Tay-Sachs disease mutations and prevalence among persons of French-Canadian heritage will be important to determine possible regional variations in gene frequencies. 相似文献
92.
93.
B Nygaard L Hegedüs FN Bennedbaek A Veje JO Faber JE Hansen 《Canadian Metallurgical Quarterly》1998,160(37):5349-5352
Traditional treatment modalities of diffuse nontoxic goitre are thyroid hormone suppression or surgery. When treating nodular nontoxic goitre with 131I treatment, a reduction in thyroid volume to about 50% is seen. In the present study we evaluated the effect of 131I treatment in 21 patients treated for a diffuse nontoxic goitre and followed by evaluation of thyroid volume measured by ultrasound. Thyroid volume declined in all patients from median of 66 ml (range 27-160 ml) to 21 ml (9-108 ml) over a year, a reduction of 62%. Three patients developed hypothyroidism in the follow-up period (14%), one of these had a temporary hyperthyroid fase. In conclusion, 131I treatment of diffuse nontoxic goitre reduces thyroid volume by approximately 60% within 12 months. Hypothyroidism developed in 14% during a limited follow-up period. 相似文献
94.
JE Max SL Koele SD Lindgren DA Robin WL Smith Y Sato S Arndt 《Canadian Metallurgical Quarterly》1998,79(8):893-899
BACKGROUND: In an effort to intensify osteosarcoma therapy, systemic ifosfamide was added pre- and postoperatively to an already aggressive three-drug regimen. In a subgroup of patients, loco-regional treatment intensification was attempted by using the intraarterial route to give cisplatin. PATIENTS AND METHODS: Patients < or = 40 years at diagnosis of a localised, de novo high-grade central extremity osteosarcoma were eligible for inclusion into study COSS-86 if registered within three weeks from biopsy. Doxorubicin, high-dose methotrexate, and cisplatin were given to all patients. Patients who fulfilled one or more of three defined high-risk criteria received early systemic treatment intensification by adding ifosfamide as the fourth agent. Preoperatively, these high-risk patients received cisplatin either intraarterially or intravenously. RESULTS: 171 eligible patients were entered, of which 128 were stratified into the high-risk group. When all 171 were analysed by intention-to-treat, actuarial overall and event-free survival rates at ten years were 72% and 66%, respectively. No benefit of intraarterial cisplatin application was detected. Cumulative treatment toxicity was considerable. CONCLUSIONS: In a multicenter setting, intensive treatment of osteosarcoma according to protocol COSS-86 led to long-term disease-free survival for two thirds of patients. We saw no benefit of using the intraarterial route to administer cisplatin. 相似文献
95.
96.
A nonlinear regeneration pulsed oscillator driven by a monochromatic source has been built. Subharmonics of the resonance carrier/modulation are measured with an accuracy of 10-10 thanks to the use of a double beats measurement set-up. The multiscale analysis of frequency readings reveals a rich fine structure which is in agreement with the nonlinear topological approach of synchronized states. 相似文献
97.
Postoperative ventilatory depression is common in patients who have received intravenous and inhalational anesthetic agents. Prompt assessment and treatment of ventilatory depression are essential to minimize morbidity and mortality. 相似文献
98.
99.
KB Reddy P Gascard MG Price EV Negrescu JE Fox 《Canadian Metallurgical Quarterly》1998,273(52):35039-35047
Signaling across integrins is regulated by interaction of these receptors with cytoskeletal proteins and signaling molecules. To identify molecules interacting with the cytoplasmic domain of the beta3-integrin subunit (glycoprotein IIIa), a placental cDNA library was screened in the yeast two-hybrid system. Two identical clones coding for a 96-amino acid sequence were identified. This sequence was 100% identical to a sequence in skelemin, a protein identified previously in skeletal muscle. Skelemin is a member of a superfamily of cytoskeletal proteins that contain fibronectin-type III-like motifs and immunoglobulin C2-like motifs and that regulate the organization of myosin filaments in muscle. The amino acid residues in the isolated clones encompassed C2 motifs 4 and 5 of skelemin. A recombinant skelemin protein consisting of C2 motifs 3-7 interacted with beta1- and beta3-integrin cytoplasmic domains expressed as glutathione S-transferase (GST) fusion proteins, but not with GST-beta2-integrin cytoplasmic tail or GST alone. The skelemin-binding region was in the membrane proximal cytoplasmic domains of the integrins. Full-length skelemin interacted with integrin in intact cells as demonstrated by the colocalization of hemagglutinin-tagged skelemin in Chinese hamster ovary (CHO) cells containing alphaIIbbeta3-integrin and by the finding that microinjection of C2 motif 4 of skelemin into C2C12 mouse myoblast cells caused spread cells to round up. A skelemin-like protein was detected in CHO cells, endothelial cells, and platelets, and this protein colocalized with beta1- and beta3-integrins in CHO cells. This study suggests the presence of a skelemin-like protein in non-muscle cells and provides evidence that it may be involved in linking integrins to the cytoskeleton. 相似文献
100.
This study investigates within-subject variations and associations of salivary viscosities and flow rates in a test panel of healthy adults. After several practice sessions, unstimulated and stimulated whole saliva samples were collected 5 times daily (at 0800, 1100, 1400, 1700, and 2000 h) from 30 university students. There was a significant within-subject variation in viscosity and flow rate of unstimulated saliva (P<0.001). Intra-item correlations were significantly different for salivary flow rates (r= 0.82 for unstimulated, r= 0.88 for stimulated, P< 0.001) and viscosity of unstimulated saliva (r= 0.54, P< 0.05), but viscosity of stimulated saliva was different in this respect. Our results indicate that there is a significant within-subject variation in viscosity of unstimulated saliva. 相似文献