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1.
Between January 1966 and August 1981, 159 patients with previously untreated squamous cell carcinomas of the anterior faucial pillar or retromolar trigone received definitive radiation therapy at The University of Texas M. D. Anderson Hospital and Tumor Institute. All except 11 patients were treated by external radiation including combination of electron beams with high-energy photons or 60Co to doses ranging from 60 Gy to 75 Gy. In the N0 patients, as a rule, only the ipsilateral subdigastric nodes were treated electively to a dose of 50 Gy. The 5-year determinate survival rate for the overall group was 83%. The cumulative recurrence rate showed that 92% of the patients had recurrence by 2 years. Therefore, all patients except those who died with no evidence of local disease less than 2 years after treatment were evaluated for local control. The failure rate for the evaluable patients was 29% for T1 lesions, 30% for T2 lesions, 24% for T3 lesions, and 40% for T4 lesions. After salvage surgery, which consisted of intraoral resection in one-third of the patients and of a composite operation in the other two-thirds, the ultimate failure rate was 0% for T1 lesions, 6% for T2 lesions, 8% for T3 lesions, and 20% for T4 lesions. Whereas stage was a poor indicator for treatment outcome, there was a significantly higher failure rate for infiltrative and/or ulcerated lesions (35%) than for exophytic or superficial lesions (15%). Histologic grade was of no prognostic significance, nor was there any significant difference in the failure rate for lesions originating on the anterior faucial pillar versus that for lesions on the retromolar trigone. Following radiotherapy, 30% of the patients developed some degree of bone exposure but only 5.6% (9 patients) required a segmental mandibular resection. The probability of bone exposure was not dose related and more likely reflected tumor location on the mucoperiosteum. Of the whole group, 16 patients (10%) experienced a neck failure with 8 ultimate failures after salvage surgery. Among the 16 patients who had neck failures, 13 were originally staged N0; 6 of these patients had failures that occurred in the electively treated ipsilateral subdigastric area, but the field was too small to cover the nodes adequately. Aspects of the radiotherapy techniques with combined electron and photon beams that may influence the treatment outcome are discussed.  相似文献   
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BACKGROUND. The distribution and correlates of serum levels of total cholesterol were studied in cross-sectional analyses of 7,439 1 to 4 year olds examined through the Arizona Department of Health Services. RESULTS. Mean cholesterol levels increased with age, and levels among 2 year olds approached those seen in adolescents. Racial and ethnic differences in cholesterol levels were observed: mean (age-adjusted) levels were 147 mg/dl among American Indians (n = 622), 153 mg/dl among Hispanics (n = 3165), 154 mg/dl among non-Hispanic whites (n = 3448), and 163 mg/dl among blacks (n = 204). Cholesterol levels were not associated either with obesity, as assessed by relative weight or the Quetelet index, or with breast-feeding during infancy. Very overweight (greater than or equal to 20 kg/m2) 3 and 4 year olds, however, tended to have higher mean levels of cholesterol than did other children. The proportion of children with borderline (170 to 199 mg/dl) or high (greater than or equal to 200 mg/dl) levels of cholesterol varied by race/ethnicity: borderline (high) levels were seen among 14% (3%) of American Indians and 29% (11%) of blacks. The proportions of white and Hispanic children having cholesterol levels between 170 and 199 mg/dl or greater than or equal to 200 mg/dl were midway between those seen among American Indians and blacks. CONCLUSION. Additional information on the interrelationships of lipids and lipoproteins may aid in the identification of children who will be at increased risk for cardiovascular disease in adulthood.  相似文献   
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Selachyl alcohol (SA) is a mono-oleyl glyceryl ether. It has certain biologic activities similar to those of the antihypertensive neutral renomedullary lipid (ANRL) derived from the renal papilla and its renomedullary interstitial cells (RIC). These include a vaso-depressor effect following bolus injection and a requirement for hepatic activation for the development of biological activity. In view of this similarity to ANRL, it appeared worthwhile to test the antihypertensive action of SA when given via the GI tract. Accordingly, pure SA was given either by gavage or by tube into the stomach or duodenum of one-kidney, one-clip hypertensive rats (5-10 mg per dose). The role of hepatic activation was demonstrated by comparing the BP response to bolus injection of SA and ANRL with and without the presence of an intact circulation to the liver. Administration of SA via the GI tract resulted in a significant decline in BP without tachycardia or weight loss. In the absence of a circulation to the liver, neither SA nor ANRL was active. SA appears to be an effective antihypertensive agent when given via the GI tract.  相似文献   
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Cases of AIDS among women of reproductive age have increased dramatically since 1981; nearly a third of all cases among females were reported in 1990 alone. Surveillance of human immunodeficiency virus (HIV) infection among women is essential for monitoring the spread of HIV over time and identifying specific populations and geographic areas in need of HIV counseling, testing, and prevention services. Blinded (unlinked) serologic surveys were conducted in the United States and Puerto Rico in sentinel clinics providing reproductive health services to women, including family planning, prenatal care, and abortion services. Seventy-eight of 94 clinics (83%) in 30 cities conducting surveys during 1988 and 1989 detected at least one HIV-positive woman. Clinic-specific prevalence ranged from 0-2.28% (median 0.22%), with rates over 1% occurring in clinics predominantly on the East Coast and in Puerto Rico. Seroprevalence varied by primary type of service, race-ethnicity, and age group. Median rates were higher in clinics offering prenatal services and lower in abortion and family planning clinics in the same cities. In general, women 25-29 years of age showed the highest median rate of infection (0.32%), and rates were higher among black women (median 0.34%) than among Hispanic (median 0.11%) and white women (median 0%). Our data indicate the need to educate women about recognizing and reducing their risk of HIV infection. Reproductive health clinics with high seroprevalence should implement voluntary HIV counseling and testing with appropriate follow-up clinical evaluation and referral for infected women. Clinics with low prevalence should seize the opportunity to enhance HIV education and prevention efforts.  相似文献   
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The A chain of the toxin ricin has been conjugated by a disulfide bond to a murine monoclonal antibody that recognizes the CD5 (T,p67) antigen present on 95% of peripheral blood T lymphocytes. This immunotoxin was used to treat a patient with severe grade III-IV, steroid-resistant, acute graft-vs-host disease (GvHD) after an allogeneic, human leukocyte antigen-identical bone marrow transplant for acute myelogenous leukemia. Immunotoxin therapy produced a complete clinical response in the skin and gastrointestinal tract. The patient tolerated a 14-day course without symptoms or signs of toxic effects. After two days of therapy, circulating T cells could not be demonstrated by indirect immunofluorescence. After therapy, acute GvHD did not recur. However, seven months after therapy the patient demonstrated mild signs of chronic GvHD that were easily controlled with low-dose immunosuppressive therapy. These findings indicate that an anti-T-cell ricin A chain immunotoxin can be given safely for treatment of acute GvHD and may be an effective therapy for this significant posttransplant complication.  相似文献   
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