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941.
AR Farina A Tiberio A Tacconelli L Cappabianca A Gulino AR Mackay 《Canadian Metallurgical Quarterly》1996,21(5):904-909
Cis-urocanic acid (cUCA) has been suggested as a mediator of impairment of contact hypersensitivity induction by ultraviolet B (UVB) irradiation. We ascertained whether topical cUCA influences local lymph node activation during induction of contact hypersensitivity. Topical cUCA or vehicle was applied during the local lymph node assay to oxazolone. Local lymph node weight and cell number were assessed in all animals. Additionally, cell proliferation rate was studied in Hartley guinea-pigs and CBA/Ca mice, whereas activation of antigen-presenting cells was quantified in NMRI mice and Wistar rats. Topical cUCA suppressed all parameters of local lymph node activation due to oxazolone application in guinea-pigs. No effect, with the exception of a suppression of antigen-presenting cell activity, was seen in mice. No effect was seen in rats. The study shows that topical cUCA may suppress local lymph node activation during contact sensitization and suggests that differences between the effect of cUCA in different animal species may exist. 相似文献
942.
Benefit of a favorable cardiovascular risk-factor profile in middle age with respect to Medicare costs 总被引:3,自引:0,他引:3
ML Daviglus K Liu P Greenland AR Dyer DB Garside L Manheim LP Lowe M Rodin J Lubitz J Stamler 《Canadian Metallurgical Quarterly》1998,339(16):1122-1129
BACKGROUND: People without major risk factors for cardiovascular disease in middle age live longer than those with unfavorable risk-factor profiles. It is not known whether such low-risk status also results in lower expenditures for medical care at older ages. We used data from the Chicago Heart Association Detection Project in Industry to assess the relation of a low risk of cardiovascular disease in middle age to Medicare expenditures later in life. METHODS: We studied 7039 men and 6757 women who were 40 to 64 years of age when surveyed between 1967 and 1973 and who survived to have at least two years of Medicare coverage in 1984 through 1994. Men and women classified as being at low risk for cardiovascular disease were those who had the following characteristics at the time they were initially surveyed: serum cholesterol level, <200 mg per deciliter (5.2 mmol per liter); blood pressure, < or =120/80 mm Hg; no current smoking; an absence of electrocardiographic abnormalities; no history of diabetes; and no history of myocardial infarction. We compared Medicare costs for the 279 men (4.0 percent) and 298 women (4.4 percent) who had this low-risk profile with those for the rest of the study group, who were not at low risk. Health Care Financing Administration charges for services to Medicare beneficiaries were used to estimate average annual health care costs (total costs, those for cardiovascular diseases, and those for cancer). RESULTS: Average annual health care charges were much lower for persons at low risk - the total charges for the men at low risk were less than two thirds of the charges for the men not at low risk ($1,615 less); for the women at low risk, the charges were less than one half of those for the women not at low risk ($1,885 less). Charges related to cardiovascular disease were lower for the low-risk groups of men and women than for those not at low risk (by $979 and $556, respectively), and charges related to cancer were also lower (by $134 and $189). CONCLUSIONS: People with favorable cardiovascular risk profiles in middle age had lower average annual Medicare charges in older age. Having optimal status with respect to major cardiovascular risk factors may result not only in greater longevity but also in lower health care costs. 相似文献
943.
SC Nahas AR Imperiale SE Araújo AA Aisaka CW Sobrado Júnior A Habr-Gama HW Pinotti 《Canadian Metallurgical Quarterly》1998,53(4):162-168
Health care is increasingly driven by information, and consequently, patient care will demand effective management of information. The report of the Priority Expert Panel E: Nursing Informatics and Enhancing Clinical Care Through Nursing Informatics challenges faculty to produce baccalaureate graduates who use information technologies to improve the patient care process and change health care. The challenge is to construct an evolving nursing informatics curriculum to provide nursing professionals with the foundation for affecting health care delivery. This article discusses the design, implementation, and evaluation of an innovative nursing informatics curriculum incorporated into a baccalaureate nursing program. The basic components of the curriculum framework are information, technology, and clinical care process. The presented integrated curriculum is effective in familiarizing students with informatics and encouraging them to think critically about using informatics in practice. The two groups of students who completed the four-course sequence will be discussed. 相似文献
944.
Although it is well documented that child maltreatment exerts a deleterious impact on child adaptation, much less is known about the precise etiological pathways that eventuate in child abuse and neglect. This paper reports on a multimethod ecological study of the relationship between neighborhood structural factors and child maltreatment reports in African American and European American census tracts. The study had two major components. First, in an aggregate analysis, the effects of four measures of community structure (impoverishment, child care burden, instability, and geographic isolation) on child maltreatment report rates were examined separately for predominantly African American (n = 94) and predominantly European American (n = 189) census tracts. Impoverishment in particular had a significantly weaker effect on maltreatment rates in African American than in European American neighborhoods. Second, focused ethnographies were conducted in four selected census tracts with child maltreatment report rates in the highest and lowest quartiles. Ethnographic data point to the importance of the social fabric in accounting for differences in child maltreatment report rates by predominant neighborhood ethnicity. 相似文献
945.
A case of a symptomatic colonic lipoma causing recurrent abdominal pain and intestinal obstruction, not treated is reported. Lipomas are the most common mesenchymal benign tumors that can be found in the colon and are second as frequence only to the adenomatous polyps. In 65% of cases the lipomas are located in the large bowel and represent the most common cause of intestinal intussusception in the adult. Lipomas are most frequent in the right colon (40%-68%) an opposite distribution in comparison with adenocarcinomas and adenomatous polyps. When their diameter is more than 3 cm, lipomas become symtomatic. In lipomas less then 2 cm in diameter it is possible an endoscopic removal while for bigger sizes the surgical laparoscopic approach is recommended. 相似文献
946.
The distribution of muropeptides formed by muramidase digestion of peptidoglycan from Staphylococcus aureus H was determined by gel-filtration HPLC. The observed crosslinking pattern supports the conclusion that incorporation of peptidoglycan in S. aureus proceeds by a similar mechanism to that proposed earlier for Bacillus megaterium. In this mechanism single glycan-peptide strands are incorporated into the sacculus by crosslinking reactions that take place only between the monomer muropeptide units of the incoming glycopeptide and muropeptides present in the innermost region of wall at the wall-membrane interface: such crosslinking reactions take place only during incorporation and no other crosslinking reactions occur. This assembly process has now been termed restricted monomer addition. The present analysis shows that the distribution of muropeptides in S. aureus peptidoglycan is in excellent agreement with that predicted by this mechanism. We propose that cell wall assembly in S. aureus proceeds via restricted monomer addition without any requirement for the secondary crosslinking reactions that have been suggested to occur in this organism. The high degree of crosslinking in S. aureus, 80% in this study, may result mainly from the freedom for crosslinking provided by the pentaglycine bridge peptide. 相似文献
947.
948.
949.
Histological and biochemical changes in the testis of rats treated with the leaf powder of A. indica are reported. The pattern of recovery is also studied at 8, 16 and 24 day after withdrawal of the treatment. In the treated rats, a general reduction in the diameters of seminiferous tubule, nuclei of the germinal elements and a mass atrophy of the spermatogenic elements has been observed. The Leydig cells are found to be atrophic. Biochemically, a decrease in the protein content and the activity of acid phosphatase and an increase in the total free sugar, glycogen, cholesterol contents and the activities of alkaline phosphatase and lactate dehydrogenase have been observed. A gradual recovery is observed in both the histological and biochemical parameters after 8.16 and 24 day of cessation of the treatment. The result suggest a possible reversible antiandrogenic property of the leaves of A. indica in male albino rats. 相似文献
950.