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71.
Vo2max and daily productivity (metric tons/day) have been measured in 46 sugar cane cutters 18 to 34 years of age. A multiple regression analysis demonstrated that productivity was simultaneously related to VO2max, height and body fat (r=0.685;P less than 0.001). The multiple regression equation was: productivity (tons/day)=0.81 VO2max-0.14 percent fat +0.03 height -1.96. The data indicate that productivity is affected indirectly by nutritional status through the influence of the latter on height, fat content and VO2max. The decrease in VO2max that occurs with age was similar to that reported in the literature. Evidence is presented that, as the worker ages, a higher percent VO2max has to be utilized to maintain productivity.  相似文献   
72.
Between 1945 and 1970, 101 children (86 girls and 15 boys) with systemic lupus erythematosus were evaluated at the Mayo Clinic. Only 9 children were less than 9 years old at the time of diagnosis. The most frequent presenting complaint was arthralgia; fever, fatigue, and a "butterfly" malar rash also were common. Renal involvement, found in more than 76 per cent of patients, was a prognostically poor sign. The overall survival of children with renal involvement is improved by the use of adequate steroid therapy.  相似文献   
73.
Some cytologic specimens may be limited in quantity, and this may hamper or preclude the performance of immunocytochemistry (ICC) in cases where more than one antibody (ab) is required by ICC to arrive at a definitive diagnosis. There is very little information in the cytology literature regarding the use of ICC for specimens that are limited in quantity. In this study, we describe a method, derived from the principles of double immunolabelling, whereby more than one ab test can be repeatedly used on the same Papanicolaou stained slide. Multiple cytologic scrape preparations fixed in 95% ethanol were obtained from fresh surgical specimens including carcinomas of the breast, endometrium, stomach, ovary and colon. Nonneoplastic tissues included tonsil (2), lymph node (2) and myometrium. Papanicolaou stained slides or unstained slides were subjected to two sequential ICC procedures, the first in which the ab was known to be nonreactive with the cells (insulin, glucagon, or somatostatin) and the second in which the ab was known to be positive in the cells. Positive controls for the known positive abs included a single-step ICC procedure as well as the tissue section. The test abs included CAM 5.2, AE1/3, K903, LCA, L26, UCHL-1, s-100, mCEA, GCDFP-15, vimentin, muscle specific actin and desmin. Identical two-step ab procedures were carried out on the tissues from the same surgical specimens. For Papanicolaou stained cytologic specimens, abs were reactive and gave excellent results for the repeat second-step ICC method. There was no false positive or false negative staining. This "repeat ICC" method also gave excellent results on the tissue sections. Immunocytochemistry can be performed more than once on the very same cytologic specimen if the initial ICC antibody attempt is negative. This method may be especially useful in situations where more than one antibody is needed on a very limited cytologic sample size.  相似文献   
74.
In vivo passage of a poorly replicating, nonpathogenic simian-human immunodeficiency virus (SHIV-HXBc2) generated an efficiently replicating virus, KU-1, that caused rapid CD4(+) T-lymphocyte depletion and AIDS-like illness in monkeys (S. V. Joag, Z. Li, L. Foresman, E. B. Stephens, L.-J. Zhao, I. Adany, D. M. Pinson, H. M. McClure, and O. Narayan, J. Virol. 70:3189-3197, 1996). The env gene of the KU-1 virus was used to create a molecularly cloned virus, SHIV-HXBc2P 3.2, that differed from a nonpathogenic SHIV-HXBc2 virus in only 12 envelope glycoprotein residues. SHIV-HXBc2P 3.2 replicated efficiently and caused rapid and persistent CD4(+) T-lymphocyte depletion in inoculated rhesus macaques. Compared with the envelope glycoproteins of the parental SHIV-HXBc2, the SHIV-HXBc2P 3.2 envelope glycoproteins supported more efficient infection of rhesus monkey peripheral blood mononuclear cells. Both the parental SHIV-HXBc2 and the pathogenic SHIV-HXBc2P 3.2 used CXCR4 but none of the other seven transmembrane segment receptors tested as a second receptor. Compared with the parental virus, viruses with the SHIV-HXBc2P 3.2 envelope glycoproteins were more resistant to neutralization by soluble CD4 and antibodies. Thus, changes in the envelope glycoproteins account for the ability of the passaged virus to deplete CD4(+) T lymphocytes rapidly and specify increased replicative capacity and resistance to neutralization.  相似文献   
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In this paper, the electromagnetic and thermal behavior of interstitial applicators was analyzed by using the Finite-Difference Time-Domain method. Two configurations were considered: a simple insulated dipole antenna radiating in a layered tissue, and an air cooled applicator radiating in a tissue-equivalent phantom. The proposed approach allows a detailed modeling of the complete structure of the applicator. Furthermore, Specific Absorption Rate and temperature distributions can be determined considering real clinical or experimental conditions. The temperature distribution for the air cooled applicator has been compared with experimental results.  相似文献   
78.
Human peripheral blood granulocytes previously were found to contain opioid delta 2-receptors mediating stimulation by opioid peptides of chemotaxis. Studies presented in this work indicate that granulocytes also contain opiate alkaloid-selective, opioid peptide-insensitive receptors mediating inhibition by morphine and other opiates of cytokine-induced activation and chemotaxis. Binding studies with [3H]morphine and [3H]diprenorphine ([3H]DPN) indicated the presence of receptor sites, at considerable density with affinities and selectivity for opiates comparable with those of the mu 3-receptor of human peripheral blood monocytes (macrophages). The influence of the guanosine 5'-triphosphate (GTP) analogue GppNHp on binding indicated that the granulocyte receptor was linked to a G protein. Morphine but not opioid peptides interfered with activation and/or chemotaxis of the granulocytes induced by TNF-alpha, IL-1 alpha, IL-8, and FMLP (chemotactic peptide). These effects of morphine were blocked by the antagonist naloxone. Levorphanol inhibited TNF-alpha-induced activation, and also potentiated the inhibition by morphine. Furthermore, in binding assays, levorphanol enhanced the affinity of the receptor for morphine. Dextrorphan had no effect on activation or chemotaxis, and it also had no effect on binding, indicative of stereoselectivity for the effect of levorphanol. It is concluded that human granulocytes contain opiate alkaloid-selective mu 3-receptors that mediate inhibitory effects of morphine on cellular activation by cytokines.  相似文献   
79.
80.
A two-color flow cytometric technique was developed to analyze poly(ADP-ribose) polymerase (PADPRP) in different individuals as a function of different physiological or pathological conditions and to establish the basis for determining whether enzyme deficiency may predispose to degenerative or malignant disorders. Peripheral blood granulocytes were devoid of enzyme activity, whereas mononuclear cells had variable amounts. PADPRP was highest in B cells, intermediate in T cells, and lowest in monocytes. This pattern of enzyme distribution and relative enzyme content of different types of cells was remarkably constant in normal subjects. In a series of 66 normal donors there was no significant biological variation in enzyme content as a function of age, race, or sex. The mean PADPRP values in peripheral blood mononuclear cells from 81 random patient samples obtained from an ambulatory oncology clinic did not differ significantly from normal subjects. However, groups of patients with breast cancer, lymphocytic malignancies, and esophageal cancer were observed to have below normal levels for peripheral blood mononuclear cell PADPRP.  相似文献   
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