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41.
Serum vitamin A status in acute lymphocytic leukemia of childhood   总被引:1,自引:0,他引:1  
Serum vitamin A status was assessed at the diagnosis in 31 children with common acute lymphocytic leukemia (CALL) and seven with T-cell leukemia (T-ALL). A control population consisting of 22 children was established to serve as one basis for comparison. Mean concentrations of vitamin A, retinol-binding protein (RBP) and prealbumin (PA) were significantly less (p less than 0.01) in the sera of patients with T-ALL when compared with the controls. Similarly, mean RBP and PA levels were reduced (p less than 0.01) in the sera of patients with CALL. In addition, "euretinolemic" and "hyporetinolemic" subgroups of CALL were identified comprising 74.2 percent and 25.8 percent of the patient population, respectively. The latter differed from the euretinolemic patients by being younger and showing an even greater decrease in the serum concentrations of RBP and PA. These findings indicate that there are factors affecting carrier proteins of vitamin A in childhood T-cell and common ALL; also, the data provide further evidence of the heterogeneity of common acute lymphocytic leukemia of childhood.  相似文献   
42.
The findings of the study did support the faculty's hypotheses. First, only 50% of the hospitals retain responsibility for the statistical function. This finding was, however, affected by the size of the hospital, with 100% of the hospitals of 400 beds or less retaining such responsibility. Second, the findings showed that only 12.5% of the hospitals had entirely manual statistical systems. However, 50% of the hospitals did compile some statistics manually, including the daily hospital census and discharge service statistics. Finally, in looking at the UT Memphis statistics curriculum and those of 14 other medical record administration programs in the Southeast, the hypothesis that curricula did not mirror this changing practice was confirmed. Although 100% of the programs surveyed had students memorize statistical formulas, only 36% had students working with computers in the statistics course. Of the 14 programs, only 6 specifically covered QA of statistical data in the statistics course, and 9 did not deal at all with how to assess the adequacy of policies and procedures for gathering statistical information. As a result of these findings, UT Memphis has modified its statistical course to increase the emphasis on computerization, QA, and assessment of statistical policies and procedures. These changes will better prepare the UT Memphis graduate for the statistical responsibilities that they will face in the workplace.  相似文献   
43.
Samples of human allograft skin prepared without freezing ("fresh skin) were found to have electrical and sodium ion transport properties which differed only slightly from those of skin which had been similarly treated but stored frozen (frozen skin). The fresh skin samples were less permeable to sodium ions during passive diffusion and less conductive than frozen skin at low current levels. They were more permselective for sodium versus chloride during constant-current iontophoresis and showed slightly more asymmetry in their current–voltage properties. Overall, the electrical behavior of the two tissues was similar enough to support the use of frozen tissue in iontophoresis studies. However, caution should be exercised when considering the use of frozen skin for applications, such as those based on electroosmosis, where the observed differences could have a major impact on the results.  相似文献   
44.
45.
A 193 base pair repeat polymorphism in the human poly(ADP-ribose) polymerase (PADPRP) pseudogene found on chromosome 13 has been associated with lung cancer, endemic Burkitt lymphoma, B-cell lymphoma, breast cancer and colorectal carcinoma. We investigated the frequency of the PADPRP genetic polymorphism in a hospital-based case-control study of lung cancer for 54 cases and 47 controls. There was a statistically significant difference in allelic frequency between Caucasians and African Americans (p<0.001). For African Americans, the odds ratio for lung cancer and the 'B' allele was 2.38 (95% C.I.=0.73, 7.69) and for Caucasians 0.44 (95% C.I.=0.11, 1.77). The results for the African Americans, however, were not in Hardy-Weinberg equilibrium, although the Caucasians were. Thus, this study, albeit small, does not find that the PADPRP pseudogene duplicated region located on chromosome 13 is a risk factor for lung cancer.  相似文献   
46.
Bowman H 《Health systems review》1995,28(4):12, 14, 16
Health providers have long assumed that they serve buyers only in their local markets, but the demands of multi-state employers are making nationwide health care purchasing more than just a distant possibility.  相似文献   
47.
An analysis of bone tumor occurrences among male and female beagles given monomeric 239Pu or 226Ra was not able to establish a difference in sensitivity to induction of bone malignancy by radium or plutonium exposure. This is in contrast to the situation reported for mice. Female mice are substantially more sensitive to 239Pu irradiation than males, but this difference is obliterated by gonadectomy, females becoming less sensitive and males becoming more sensitive. Although there may be some nonuniformity between human males and females for radiation-induced bone sarcoma occurrence, analysis of data sets containing both men and women exposed to 224Ra, 226Ra, 228Ra, or 226+228Ra appears not to reveal substantial differences in sensitivity by gender, a situation similar to that reported herein for beagles.  相似文献   
48.
When parents with AIDS become too ill to care for their children, or pass away, it is too late to insure that their wishes regarding caring for their children are followed. Legal and financial aspects relating to this type of decision are discussed. Different types of guardianship are described, including temporary care and permanent custody.  相似文献   
49.
BACKGROUND: RNs in North Carolina were surveyed to determine their current knowledge and to determine if educational preparation, practice setting, or clinical specialty influenced their knowledge levels and attitudes. METHOD: A stratified random sample of 1,000 practicing RNs in North Carolina were surveyed using the Nurses' Knowledge and Attitudes Survey Instrument developed by McCaffery and Ferrell. RESULTS: The mean score was 64.58 based on the percentage of correct responses from the 260 subjects who participated. No statistically significant difference was found in scores based on educational preparation, practice setting, or clinical specialty. CONCLUSION: The findings of this study support the concern of inadequate knowledge and inappropriate attitudes regarding pain management. It reveals the need for intensive continuing education and staff development.  相似文献   
50.
Atrial morphologic features in tricuspid atresia.   总被引:1,自引:0,他引:1  
We studied the atrial morphology in 110 hearts removed at autopsy from patients with tricuspid atresia. Ten of the patients had had a Fontan operation. We compared the findings in these hearts with those in 30 normal hearts. Prominent eustachian valves were common (40%). The tricuspid "dimple," present in 33 of 100 specimens, denoted the membranous atrioventricular septum and was never related to the right ventricle. Most interatrial communications (85/100) were nonobstructive. A minority of patients with obstructive interatrial communications (13/100 = small, 2/100 = severely obstructive) would be expected to benefit from balloon atrial septostomy early in life. Right atrial hypertrophy was greatest in specimens with restrictive interatrial communications (severely obstructive = 3.2 +/- 0.3 mm, small = 2.1 +/- 0.6 mm) and in those that had been subjected to a Fontan operation (3.2 +/- 0.7 mm), but thickness was also increased in hearts with nonobstructive interatrial communications (1.6 +/- 0.5 mm) compared with normal hearts (1.1 +/- 0.2 mm; p less than 0.001 versus all groups). Of the patients in the series, 11 of 100 had left juxtaposition of the atrial appendages, which may have important implications for the Fontan operation.  相似文献   
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