摘要:

Fetal hemoglobin, the predominant hemoglobin of the fetus, is good for sickle cell anemia. This hemoglobin inhibits the polymerization of sickle hemoglobin. Clinical studies have shown that at any level of fetal hemoglobin, the more that is present, the better off is the patient. We are now able to increase fetal hemoglobin levels by pharmacologic means. We should know shortly if this is associated with clinical benefit.

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The synergistic effects of combining fish oil (FO) diet, which reduces thromboxane A production, with the free radical scavenger, dimethylthiourea (DMTU), were evaluated in acute adriamycin nephrosis, because proteinuria in adriamycin nephrosis is mediated by increased renal thromboxane A and free radical production. The effects of combined evening primrose oil (EPO) and DMTU were compared with the DMTU + FO combination because EPO increases prostaglandin E but not thromboxane A. After 7, 14, and 21 days, proteinuria was significantly (p < 0.05) reduced in rats receiving either DMTU + corn oil (CO) or DMTU + FO compared with untreated control rats. However, after 21 days, rats receiving DMTU + FO had significantly reduced urine protein excretion compared with those receiving DMTU + CO (103.9 ± 20 mg daily vs 351.8 ± 29.8 mg daily;P< 0.05). In contrast to FO, rats receiving EPO + DMTU had similar urine protein excretion to rats receiving DMTU + CO after 21 days (170.2 ± 20.34 mg daily vs 179.45 ± 26.38 mg daily). The mean serum cholesterol concentration was significantly (P< 0.01) reduced in rats receiving DMTU + FO (195.2 ± 23.8 mg/dL) compared with DMTU + CO (377.9 ± 28.5 mg/dL). Serum triglyceride levels also were significantly (P< 0.01) reduced in rats receiving DMTU + FO (52.5 ± 26.4 mg/dL) compared with DMTU + CO (100.5 ± 36.9 mg/dL). No significant differences in serum cholesterol concentrations or triglycerides occurred between rats receiving DMTU + CO and DMTU + EPO. Renal glutathione content was significantly (P< 0.05) increased by 23% in normal rats receiving FO diet and by 34% in rats receiving combined DMTU + FO compared with CO alone. Evening primrose oil did not enhance renal glutathione content. The authors conclude that FO diet, but not EPO, is synergistic with DMTU in reducing proteinuria and hyperlipidemia in adriamycin nephrosis, possibly by enhancing the free radical scavenging ability of DMTU.

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The prevalence of hypertension in rural African communities has been reported previously to be relatively low, with prevalence rates ranging between 2.5% and 10.9%. The authors obtained blood pressure recordings in 3,588 adult residents (age > 20 years) of the Liberian Agricultural Company rubber plantation, located in rural Liberia, West Africa. Blood pressures were obtained using automated digital blood pressure machines in a house-to-house survey. Individuals with a systolic blood pressure greater than 139 mm Hg or a diastolic blood pressure greater than 89 mm Hg were referred to a central site, where three subsequent blood pressure determinations were made, the mean of which was used to determine whether people were hypertensive. The overall prevalence of hypertension (blood pressure > 139/89 mm Hg) was 12.5%. Hypertension was most common in the older women (prevalence 5.7% in women age 20–24 years old, 50% in women older than 55). Using more stringent criteria for hypertension, systolic blood pressure greater than 159 mm Hg or diastolic blood pressure greater than 94 mm Hg, 20% of women between 50–54 had hypertension and 26% of the women older than 55 had hypertension. In some ethnic groups, the prevalence of hypertension was as high as 25%. Based on these results, the prevalence of hypertension in some rural African communities may be higher than reported previously, particularly in older women and among certain ethnic groups, possibly suggesting a strong hereditary component.

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The authors' objective, with this study, was to determine the use in routine clinical practice of the cobalamin serum assay in evaluating patients suspected of having cobalamin deficiency. The design was a prospective observational study of a diagnostic test compared with a criterion gold standard. The setting was the Veterans Affairs hospital inpatient wards and outpatient clinics. The authors prospectively identified all patients who had serum cobalamin measured and enrolled all those with cobalamin < 133 pmol/L (180 pg/mL) and a random sample of patients with cobalamin greater than or equal to 133 pmol/L (N= 168). There were no interventions.To identify cobalamin deficiency, subjects underwent blinded clinical and laboratory examinations, Schilling test, and urinary methylmalonic acid assay, with a trial of cobalamin replacement, if needed. Of 1,599 patients assayed, 84 (5.2%) had low cobalamin levels. After evaluation, 16 of those with low cobalamin levels, but none of those with normal cobalamin levels, were confirmed as deficient. Positive predictive value of a low cobalamin level in this population was 22.2% (95% confidence interval, 12.6–31.8%). After correcting for sampling procedure, the calculated sensitivity rate was 100% (95% confidence interval, 20.6–100%), and specificity rate was 95.8% (95% confidence interval, 95.2–100%). The authors conclude that in routine use, the positive predictive value of the cobalamin assay is low. Low cobalamin levels should not be used alone to justify a lifetime of parenteral therapy or to rule out other conditions that mimic cobalamin deficiency.

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

In this article, the authors explore senior medical students' specialty preferences and investigate factors that influence those preferences. The design of the study was a written questionnaire. The setting was a large, state-supported university-based southern medical school. The patients/participants were students entering the fourth year of medical school. One hundred seventy-six students (97% of the class) completed the questionnaire. Of those students, 12.5% were interested only in primary care, 43.2% were interested in both primary and nonprimary care, and 44.3% were interested in nonprimary care careers. Most students considering both primary and nonprimary care careers were interested in general internal medicine or general pediatrics and subspecialties within those fields. Career choice was influenced most strongly by several factors—clerkship experiences, the fact that it fit with skills/abilities, physician role models, the challenge, and intellectual content. Encouragement from family and other students, prestige, and income potential had the least impact on career choice. Students interested in primary care careers valued providing continuity of care much higher than did those interested in nonprimary care specialties. The authors conclude that students' experiences in medical school, particularly during the clerkships, have a significant impact on their specialty choice.

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Hereditary predisposition to colorectal cancer assumes two well-defined forms: familial adenomatous polyposis and hereditary nonpolyposis colon cancer. These tumors segregate as autosomal dominant conditions whose penetrance increases with age; cancer is expected to develop ultimately in as much as 50% of the offspring of affected individuals. These traits account for less than 1% and approximately 5% of all colorectal cancer, respectively. In addition, first-degree relatives of patients with common (sporadic) colorectal neoplasia are at increased risk of colorectal cancer. This relative risk averages approximately twofold but is significantly higher for relatives of younger patients (age at diagnosis, <55 years). Familial adenomatous polyposis and a major subset of hereditary nonpolyposis colon cancer are due to loss-of-function germline mutations of genes located on chromosomes 5q and 2p, respectively. Both of these genes have been cloned recently. The gene affected in familial polyposis,APC, encodes a protein of unknown function that normally is found on the surface of maturing cells in the upper colonic crypts. The relevant gene in many hereditary nonpolyposis colon cancer kindreds ishMSH2. This gene encodes the human homologue of a bacterial protein MutS, which is part of a system known to repair base mismatches in newly replicated DNA. Loss ofhMSH2function may explain the strikingly erroneous replication of short DNA repeats (microsatellites) in colon tumors from patients with hereditary nonpolyposis colon cancer. Because this error-prone replication is found in approximately 13% of nonfamilial colon cancers, defective mismatch repair may contribute to the development of both hereditary and sporadic colon neoplasia. Molecular genetic assays to detect mutated alleles of these genes will facilitate pre-symptomatic identification of carriers in families with familial polyposis and hereditary nonpolyposis colon cancer. Current recommendations for surveillance of family members are presented in the light of the new genetic understanding of these diseases.

ISSN:0002-9629    

出版商:OVID    

年代:1994

数据来源: OVID