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131.
本研究采用先进的三维超声成像技术及多普勒技术对正常育龄妇女月经周期中心血管功能进行研究。结果:月经周期中HR、BP无变化;血清E2是周期性变化,排卵前达高峰。SV、CO、EF在排卵前期升高达峰值,显著高于月经期和黄体期;SVR排卵前期最低,而Ved、Ves无变化。Vmax、A、E在内源性E2高峰时明显加快,而E/A比值无明显变化。结果提示:月经周期中随内源性E2的周期性变化,心脏功能也发生周期性变化。E2高峰时,心输出量、心搏量和射血分数达最高。外周阻力最低,心脏内血流速度加快。 相似文献
132.
133.
Previous studies have demonstrated that progressive growth of the weakly immunogenic MCA 106 murine sarcoma stimulated, in the draining lymph nodes, the production of tumor-sensitized but not fully functional preeffector lymphocytes. These lymphocytes could develop into specific immune effector cells after sequential in vitro activation with anti-CD3 monoclonal antibody and interleukin 2 (IL-2). In this study, we analyzed cellular requirements for in vivo sensitization of preeffector cells, for generation of immune effector cells by the method of anti-CD3/IL-2 activation, and for adoptive immunotherapy mediated by activated cells. By selective depletion of T-cell subsets in vivo, we found that tumor regression after systemic adoptive immunotherapy required the collaboration of activated CD4+ and CD8+ cells. It was further demonstrated that CD8+ immune cells alone could mediate antitumor effects if exogenous IL-2 was provided in vivo. These results suggest that CD8+ cells served as immediate effector cells, whereas CD4+ immune cells provided a helper function via the secretion of IL-2. During in vitro anti-CD3/IL-2 activation, generation of effector cells depended on the collaborative interaction between previously sensitized CD4+ and CD8+ preeffector cells. At the stage of in vitro activation, the addition of IL-2 could not substitute the function of CD4+ cells. We next examined whether the sensitization of preeffector cells in the draining lymph nodes required cellular interactions between CD4+ and CD8+ T-cells. By in vivo depletion of T-cell subsets during tumor growth, we found that CD4+ cells were sensitized independently of CD8+ cells. More interestingly, in vivo sensitization of CD8+ preeffector cells also occurred independently in the absence of a CD4+ helper cell response. The lack of T-cell-T-cell interactions in vivo may explain the failure of effector cell generation during progressive tumor growth. Taken together, these results demonstrate that the anti-CD3/IL-2 activation defines an immune response distinct from many previously described mechanisms of antitumor immune responses. 相似文献
134.
Comparison of polychlorinated dibenzodioxin levels with hepatic mixed-function oxidase induction in great blue herons 总被引:3,自引:0,他引:3
G D Bellward R J Norstrom P E Whitehead J E Elliott S M Bandiera C Dworschak T Chang S Forbes B Cadario L E Hart 《Journal of toxicology and environmental health》1990,30(1):33-52
As part of the Canadian Wildlife Service monitoring of great blue herons in British Columbia, eggs were collected from three colonies with low, intermediate, and high levels of PCDD and PCDF contamination: Nicomekl, Vancouver, and Crofton, respectively. One egg from each nest was used for chemical analysis by GC-MS; the others were hatched. Liver microsomes were prepared from the heron chicks and used for determination of cytochrome P-450-dependent activities. No erythromycin N-demethylase activity was found in any sample. Ethoxyresorufin O-dealkylase activity in the Nicomekl group was similar to that in pigeons, a control altricial species. The ethoxyresorufin activity in the herons from the Crofton colony was 2.6-fold higher than in the Nicomekl group. The Vancouver colony was intermediate. No difference among the three heron colonies was found in pentoxyresorufin O-dealkylase activity, although levels were 20-33 times that in the pigeon. Chemical analysis was carried out on paired heron eggs. Vancouver and Crofton eggs contained 13.5 and 21 times the levels of 2,3,7,8-TCDD compared to the Nicomekl group. The Crofton eggs contained higher levels of several other contaminants also. A highly significant correlation (p less than .001) was found between ethoxyresorufin O-dealkylase and 2,3,7,8-TCDD concentrations. The correlation coefficient did not change when ethoxyresorufin O-dealkylase was compared to total chemical contamination using several toxic equivalency factors. Multiple regression analysis resulted in only one predictor variable for ethoxyresorufin O-dealkylase: 2,3,7,8-TCDD. 相似文献
135.
本文报道老年非何杰金氏淋巴瘤(NHL)59例并与同期非老年患者138例相比。老年患者占同期NHL总数的29.9%。59例中有结内型43例,结外型16例;低度恶性与中度恶性各12例,高度恶性35例。与非老年组比较,老年组的就诊原因、病变部位、恶性程度、细胞类型和预后等方面无何差别,提示年龄对上述特征无明显影响。 相似文献
136.
Expression of major histocompatibility complex class II antigens was investigated in the normal lungs and in lung allografts of mongrel dogs after single-lung transplantation. Cryostat sections were stained with an indirect immunoperoxidase technique that used B1F6 and 7.5.10.1 as anti-MHC class II monoclonal antibodies. In the normal lungs and native lungs of the recipient dogs after single-lung transplantation, only some cells of lymphoid tissue and macrophages/dendritic cells were MHC class II-positive. During acute rejection, increased infiltration with MHC class II-positive cells in perivascular, peribronchial, and interstitial areas and intraalveolar spaces was found in lung allografts. In addition, expression of MHC class II antigens was induced on the bronchial epithelium and vascular endothelium. Induced expression of MHC class II antigens on the bronchial epithelium and vascular endothelium in rejecting lung allografts was found as early as two days after single-lung transplantation. The intensity of MHC class II antigen expression on bronchial epithelium and vascular endothelium in graft lungs increased with the progression of rejection response and directly correlated with the bronchoalveolar lavage fluid (BALF) levels of biochemical markers, as tumor necrosis factor alpha, gamma-interferon (IFN-gamma), interleukin 2 (IL-2) and soluble interleukin 2 receptor (SIL-2R). Abnormal expression of MHC class II antigens on bronchial epithelium and vascular endothelium and abnormal elevation of BALF levels of the cytokines in lung allografts could be prevented by cyclosporine (CsA) treatment. Our results suggested that MHC class II antigen expression could be induced on the bronchial epithelium and vascular endothelium of canine lung allografts during acute rejection. This abnormal expression of MHC class II antigens on bronchial epithelium and vascular endothelium of graft lungs may serve as a specific index for diagnosis of lung allograft rejection when infection as an inducing factor can be excluded. Furthermore, bronchial epithelium and vascular endothelium of lung allografts have become MHC class II-positive, and are likely to be the targets for low-grade rejection, resulting in the development of bronchiolitis obliterans and occlusive vascular disease in lung allografts. 相似文献
137.
J. K. Kang Sang Won Lee Min Woo Baik Byung Chul Son Yong Kil Hong Chul Ku Jung Keon Hee Ryu 《Child's nervous system》1998,14(7):297-301
Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult
owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair
over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion
practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell
mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate
if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was
used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and
EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients
(10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement
of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment
of the primary craniosynostosis.
Received: 16 February 1998 相似文献
138.
Gastrointestinal dysfunction among intensive care unit patients 总被引:3,自引:0,他引:3
This study used the Acute Physiological and Chronic Health Evaluation (APACHE II) system to select two groups of ICU patients with comparable risk of hospital death to evaluate the importance of GI dysfunction, defined as failure to tolerate enteral nutrition (EN), as a prognostic factor. In our ICU, patients who have not undergone recent bowel surgery are treated by EN. Those patients who cannot tolerate EN are treated by total parenteral nutrition (TPN). One hundred and eleven patients who tolerated EN (functioning gut) and 97 TPN patients who failed to tolerate EN (GI dysfunction) were studied. The mean APACHE II scores of the two groups were 17.7 +/- 6.5 (SD) and 17.7 +/- 5.1, respectively. The observed mortality of patients with GI dysfunction (51%) was significantly higher (p less than .0005) than that of patients with a functioning gut (25%). This was associated with significantly poorer APACHE II mean BP, oxygenation, and creatinine scores among the GI dysfunction patients. Our results suggest that shock, ischemia, and hypoxemia, in addition to causing impairment of renal function, may bring about changes in the GI tract, evident clinically only as a failure to tolerate EN, which have an adverse effect on the prognosis of ICU patients so affected. 相似文献
139.
Biosynthesis of the antibiotic actinorhodin. Analysis of blocked mutants of Streptomyces coelicolor 总被引:6,自引:0,他引:6
From two types of class V act mutants of Streptomyces coelicolor two monomeric precursors of actinorhodin have been isolated and their structures determined. One is the known antibiotic kalafungin and the other a new compound. Their relationship to actinorhodin biosynthesis is discussed. 相似文献
140.