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991.
病毒性肝炎患者血清一氧化氮变化及其临床意义 总被引:6,自引:1,他引:5
0 引言 一氧化氮 (NO)是近年来认识的一种新型的细胞间信息交换的重要载体 ,兼有第二信使和神经递质的功能 ,广泛参与生理功能的调节和病理过程的发生 .一氧化氮与病毒性肝炎二者的关系已引起医学界的广泛关注 ,为此 ,本实验测定了病毒性肝炎患者血清一氧化氮的含量 ,并初步探讨其在病毒性肝炎中的临床意义 .1 材料和方法1.1 病例选择 病例均为唐都医院住院患者 87(男 6 2 ,女2 5 )例 ,年龄 10~ 6 3岁 ,平均 31岁 .87例住院患者包括急性黄疸性肝炎 37例 ,慢性肝炎 38例 ,重型肝炎 12例 .诊断全部符合 1995 - 0 5北京全国病毒性肝炎会… 相似文献
992.
TS RAGHU RAMAN RA GUPTA AK GUPTA B RAVICHANDER SL SOOD 《Medical Journal Armed Forces India》1997,53(2):99-103
One hundred, non-consecutive, non-randomized, cases of tuberculosis divided in 2 groups i.e. Group A including 50 BCG vaccinated children and Group B including 50 unvaccinated children were studied to determine the pattern of tuberculosis and the role of protein energy malnutrition in the pathogenesis of tuberculosis. Thirty four per cent of Group A and 52 per cent of Group B had severe protein energy malnutrition. Sixty eight per cent in Group A and 76 per cent in Group B had intrathoracic forms of tuberculosis. Twelve (24%) patients in Group A and 11 (22%) in Group B suffered from serious forms of tuberculosis including tubercular meningitis, miliary tuberculosis and disseminated tuberculosis. The difference was not statistically different (p>0.05). However, in severe form of tuberculosis, the morbidity in vaccinated group was less. Sixty six per cent of vaccinated children with disseminated forms of tuberculosis had features of severe protein energy malnutrition. BCG is not effective in preventing tubercular infection in children of preschool age. It is effective to a certain extent in localizing the infection to a particular organ. Severe protein energy malnutrition is a contributing factor in the genesis of tuberculosis in preschool children vaccinated with BCG at or immediately after birth.KEY WORDS: BCG vaccine, Protein energy malnutrition, Tuberculosis 相似文献
993.
Song PY Washington M Vaida F Hamilton R Spelbring D Wyman B Harrison J Chen GT 《International journal of radiation oncology, biology, physics》1996,34(1):213-219
PURPOSE: To determine the variability of patient positioning during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer treated with no immobilization or one of four immunobilization devices, and to determine the effects of patient body habitus and pelvic circumference on patient movement with each individual inmobilization technique. METHODS AND MATERIALS: To see whether our immobilization techniques have improved day-to-day patient movement, a retrospective analysis was carried out. A total of 62 patients treated at one facility on a single machine with 3D-CRT via a four-field box technique (anterior-posterior and opposed laterals) in the supine position with either no immobilization or one of four immobilization devices. Five groups of patients were compared: (a) group 1-no immobilization; (b) group 2-alpha cradle from the waist to upper thigh; (c) group 3-alpha cradle from waist to below the knees; (d) group 4-styrofoam leg immobilizer (below knees); and (e) group 5-aquaplast cast encompassing the entire abdomen and pelvis to midthigh with alpha cradle immobilization to their lower legs and feet. Prior to starting radiotherapy, portal films of all four treatment fields were obtained 1 day before treatment. Subsequently, portal films were then obtained at least once a week. Portal films were compared with the simulation films and appropriate changes were made and verified on the next day prior to treatment. A deviation of greater than 0.5 cm or greater was considered to be clincally significant in our analysis. We studied the difference among the types of immobilization and no immobilization by looking at the frequency of movements (overall, and on each of the three axes) that a patient had during the course of his treatment. Using a logistic regression model, the probability of overall and individual directional movement for each group was obtained. In addition, the effects of patient body habitus and pelvic circumference on movement were analyzed. RESULTS: The maximum deviation was 2 cm and the median deviation was 1.2 cm. For each patient, the probability of movement ranged from 0 to 76%, with a mean of 39%. There was no significant difference seen in overall movement with any of the immobilzation devices compared to no immobilization, but there was less vertical (9 vs. 18%; p = 0.03) and AP (6 vs. 15%; p = 0.14) movement with the aquaplast than any other group. However, when examining the lateral direction, the aquaplast had significantly more movement (32 vs. 9%; p < 0.001). When accounting for body habitus and pelvic circumference, no immobilization device was effective in reducing movement in obese patients or in patients with pelvic circumference greater than 105 cm. The aquaplast group had a significantly increased amount of lateral movement with obesity (42 vs. 23%; p < 0.05), and with pelvic circumference >105 cm (33 vs. 29%; p < 0.05). CONCLUSIONS: There was no significant reduction in overall patient movement noted with any of the immobilization devices compared to no immobilization. The aquaplast group had reduced vertical and AP movement of greater than 0.5 cm. There was significantly more lateral movement with aquaplast appreciated in obese patients or patients with pelvic circumferences greater than 105 cm. The aquaplast immobilization appears to be useful in reducing movement in two very clinicaly important dimensions (AP and vertical). Despite our findings, other immobilization may still be useful especially in the treatment of nonobese patients. It is clear that the optimal immobilization technique and patient positioning are yet to be determined. 相似文献
994.
Campbell MK Symons M Demark-Wahnefried W Polhamus B Bernhardt JM McClelland JW Washington C 《American journal of health promotion : AJHP》1998,12(3):185-191
PURPOSE: This study examined the relationship between stages of change, other psychosocial factors, and fruit and vegetable (F&V) consumption among rural African-Americans participating in a 5 a Day study. DESIGN: The cross-sectional design assessed associations between F&V intake, stage of change, self-efficacy, beliefs, barriers, and social support. SETTING: Participants were surveyed by telephone. SUBJECTS: Subjects were 3557 adult church members (response rate, 79.1%), aged 18 and over from 10 North Carolina counties. MEASURES: A seven-item food frequency measured F&V intake. Stage of change was measured using four items; other psychosocial variables were measured using Likert scales. Chi-square tests and analysis of variance were used in statistical analyses. RESULTS: The majority of participants (65%) were in the preparation stage of change. Individuals in action/maintenance consumed an average of 6.5 daily F&V servings compared to 3.3 to 3.5 servings for those in precontemplation, contemplation, and preparation. Self-efficacy, social support, and belief about how many daily F&V servings are needed, were positively associated with stage. Barriers were most prevalent among precontemplators. CONCLUSIONS: The findings support the applicability of the stages-of-change model to dietary change among rural African-Americans. The relationship between stage, self-efficacy, social support, and barriers supports using a multicomponent intervention strategy. 相似文献
995.
996.
Macrophages are necessary for maximal nuclear factor-kappa B activation in response to endotoxin 总被引:6,自引:0,他引:6
Koay MA Gao X Washington MK Parman KS Sadikot RT Blackwell TS Christman JW 《American journal of respiratory cell and molecular biology》2002,26(5):572-578
To define the role of macrophages in regulating the lung's response to Escherichia coli endotoxin (lipopolysaccharide [LPS]), depletion of macrophages was accomplished by administration of dichloromethylene diphosphonate (clodronate) delivered via intratracheal (i.t.) and/or intravenous (i.v.) routes. Clodronate reduced the number of macrophages in lung lavage 48 h after either i.t. or i.v. administration, but combined i.t. + i.v. clodronate achieved the most profound depletion (90%). Although i.t. clodronate alone had little effect on the evolution of lung inflammation, combined i.t. + i.v. clodronate treatment decreased neutrophilic alveolitis 4 h after exposure to aerosolized LPS by 80% compared with mice treated with empty liposomes. This decrease was associated with impaired activation of nuclear factor (NF)-kappa B and lower concentrations of tumor necrosis factor (TNF)-alpha in lung lavage fluid. Combined i.t. + i.v. clodronate markedly reduced lung NF-kappa B activation and the intensity of neutrophilic alveolitis after intraperitoneal (i.p.) LPS; however, i.v. clodronate alone had no effect on NF-kappa B activation in either liver or lung tissue or the development of neutrophilic alveolitis. We conclude that generalized macrophage depletion reduces NF-kappa B activation, generation of cytokines, and neutrophilic lung inflammation in response to gram negative bacterial endotoxin. These findings define the role of the macrophage as a critical component for initiation of the NF-kappa B-dependent innate immune response. 相似文献
997.
Four consecutive studies comparing commercially prepared bottles that contained brain heart infusion, brucella (vented and unvented), and Trypticase soy broths with Tryptic soy broth failed to demonstrate significant differences in rates of isolation of organisms from blood. Statistically significant differences between bottles were limited to the average times required to detect growth of viridans streptococci in one study and of all organisms in another. 相似文献
998.
We have examined the distribution of alpha beta and gamma delta T cells, together with B cells, in a range of lymph nodes and blood before and after birth. The proportions of blood-borne alpha beta and gamma delta T cells changed markedly during development with a wave of increasing numbers of blood-borne gamma delta T cells occurring in the fetus during the last month of gestation and early postnatal life. gamma delta T cells constituted 18% of T cells in the blood of fetal lambs one month before birth and 60% of T cells in the blood of lambs one month after birth. There were also changes in the numbers of alpha beta T cells circulating through lymph nodes after birth. The proportion of CD4+ and CD8+ cells in mesenteric nodes increased substantially after birth, whereas that of gamma delta T cells decreased. Although B cells were present in much larger numbers in ileal lymph nodes in both the fetus and lamb, there was a large increase in the concentration of B cells in all lymph nodes in lambs after birth. In addition to the differences in the distribution of lymphocyte subsets circulating in fetal and postnatal lambs, markedly different growth patterns were also observed between lymph nodes before and after birth. 相似文献
999.
Lymphocyte subset-specific and tissue-specific lymphocyte-endothelial cell recognition mechanisms independently direct the recirculation of lymphocytes from blood to lymph in sheep.
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Tissue-specific and lymphocyte subset-specific lymphocyte recirculation patterns have been analysed simultaneously. Lymphocytes obtained from one lymph compartment were directly labelled with fluorochrome in vitro and returned to the blood of the same animal. Over the next 48-72 h, the recirculation of these cells into both the same lymph compartment and at least one different lymph compartment was monitored. The cells in all of these lymph collections, as well as an aliquot of the cells used for direct fluorescent labelling, were then phenotyped with monoclonal antibodies (mAb) which define the mutually exclusive small CD4+ and CD8+ T-lymphocyte subsets in sheep. All cell samples were analysed by flow cytometry and CD4/CD8 ratios were determined for the recirculated, fluorochrome-labelled population in each lymph collection. The mean CD4/CD8 ratio calculated for each lymph compartment was then compared with the CD4/CD8 ratio calculated for each lymph compartment was then compared with the CD4/CD8 ratio of the transfused, starting population. In one experiment employing efferent prescapular lymph cells, three experiments employing efferent intestinal lymph cells, and two experiments employing afferent intestinal lymph cells, tissue-specific recirculation was observed. In all of these experiments, the pattern of recirculation of small CD4+ and CD8+ T lymphocytes was non-random. Moreover, in each experiment, this non-randomness was completely unrelated to tissue-specific phenomena, since the mean CD4/CD8 ratio of the recirculated population was higher than the CD4/CD8 ratio of the transfused, starting population regardless of the lymph compartment examined. These data are therefore consistent with the hypothesis that tissue-specific and lymphocyte subset-specific lymphocyte-endothelial cell recognition mechanisms independently direct the recirculation of small lymphocytes from blood to lymph. 相似文献
1000.
The proliferative response after partial hepatectomy is inhibited in rats denied food. Following a starvation period of 48 hr the initial evidence of proliferative activity is delayed some five hours after which the response steadily increases but does not reach the value obtained for the fed animals.The inhibition is more marked and the mitotic index is further depressed when the period of starvation before partial hepatectomy is increased to 72 hr.The factors responsible for the inhibition operate early in the mitotic cycle and delay DNA synthesis. The inhibition is not affected by the administration of glucose or glucagon nor by reducing the severity of the operation. 相似文献