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71.
以P(St-Am·MG)对染料活性艳红(X-3B)溶液进行絮凝试验,考察了高聚物剂量及外加盐对絮凝效果的影响,并与无疏水基团的阳离子聚丙烯酰胺PAm·MG的絮凝能力进行了比较。发现絮凝体系无外加盐时,高聚物与染料的作用主要是通过静电力;有外加盐时,高聚物的电荷受到屏蔽,高分子链卷曲,PAm·MG的絮凝效果受到较大影响。而P(St-Am·MG)与X-3B之间存在疏水相互作用,受影响较小,此时P(St-Am·MG)的絮凝性能优于PAm·MG。用平衡渗析法研究了不同温度时甲醇和脲存在下P(St-Am·MG)与X-3B相互作用的热力学。证明了它们之间确实存在疏水相互作用。  相似文献   
72.
目的探讨活动性肺结核(APTB)患者血清Fad D9重组蛋白、可溶性白细胞分化抗原14亚型(sCD14-ST)、单核细胞P糖蛋白(Pgp)表达及其临床意义。 方法选取96例APTB患者(APTB组),按照肺部病灶有无空洞和病灶肺叶数分亚组。同期选择体检健康且经γ干扰素释放试验检测阴性者(健康对照组,HC组)及阳性者(结核潜伏感染组,LTBI组)各48例。比较各组血清Fad D9重组蛋白、sCD14-ST、Pgp水平。评估Fad D9重组蛋白、sCD14-ST、Pgp诊断APTB和鉴别APTB、LTBI的价值。 结果Fad D9重组蛋白、sCD14-ST、Pgp水平APTB组>LTBI组>HC组,且有空洞者高于无空洞者,病灶肺叶≥3个者高于<3个者(P<0.05)。Fad D9重组蛋白、sCD14-ST、Pgp对APTB诊断和APTB、LTBI鉴别有良好效能(P<0.05)。 结论APTB患者血清Fad D9重组蛋白、sCD14-ST及Pgp明显升高,且与肺部病灶的严重程度有关。  相似文献   
73.
[目的] 探索甘草地上部分活性部位对小鼠的急性毒性及大鼠的长期毒性,评价其安全性,为合理开发利用甘草地上部分资源以及临床应用提供可靠的理论依据。[方法] 甘草地上部分活性部位33.2 g/kg灌胃给予昆明种小鼠,24 h内两次(间隔5 h)经口灌胃给予受试物,持续观察14 d内小鼠的急性毒性反应;SD大鼠随机分为对照组和甘草地上部分低、中、高剂量组,按8.3、16.6、33.2 g/kg剂量连续灌胃甘草地上部分活性部位90 d,观察大鼠的一般状况,并分别于给药后45、90 d进行血液学指标检测与血清生化指标检测,给药后90 d进行大体解剖及病理学检查,观察甘草地上部分活性部位的长期毒性反应。[结果] 急性毒性实验中小鼠的一般状态、饮食、分泌物、排便未见异常,无小鼠死亡,肉眼尸检心、肝、脾等主要脏器组织未见明显异常;长期毒性实验中,各组大鼠与对照组比较,一般状况、血液学及血清生化指标未见明显差异;病理检查未见主要脏器组织形态学改变。[结论] 甘草地上部分活性部位无急性毒性和长期毒性,在治疗剂量范围内用药安全性高。  相似文献   
74.
目的 探讨血液肿瘤患者肛拭子耐碳青霉烯类肠杆菌(CRE)主动筛查情况及继发血流感染的影响因素。方法 选取2020年9月—2022年6月在苏州大学附属第一医院治疗的血液肿瘤患者1 258例,所有患者行肛拭子CRE主动筛查,分析CRE定植分布、血流感染情况及其影响因素。结果 共检出CRE 109株,以肺炎克雷伯菌、大肠埃希菌为主;10例患者发生CRE血流感染;CRE酶型分布中,主要以NDM、KPC为主;有中性粒细胞缺乏患者CRE定植发生率高于无中性粒细胞缺乏患者(P<0.05);有消化道症状患者CRE定植发生率高于无消化道症状患者(P<0.05);多因素逐步Logistic回归分析结果显示,中性粒细胞缺乏■是血液肿瘤患者CRE定植发生的影响因素(P<0.05)。不同性别、年龄、疾病类型及有无中性粒细胞缺乏、消化道症状患者的血流感染发生率比较,差异均无统计学意义(P>0.05)。结论 血液肿瘤患者肛拭子CRE主动筛查能有效筛出CRE感染者,CRE定植感染与中性粒细胞缺乏有关,临床应加以重视。  相似文献   
75.
We studied the histological and ultrastructural changes in the liver and alterations in the liver test results before, during, and after treatment with human interferon- from five patients with hepatitis B e antigen-positive chronic active hepatitis. A daily dose of 3×106 to 6×106 units of interferon- was given intravenously for four weeks. The total index of periportal and portal inflammation, intralobular degeneration, and focal necrosis before treatment was decreased significantly six months after treatment (P<0.05). Ultrastructurally, the structure of endoplasmic reticulum was irregularly shaped or fragmentally decreased during treatment, but these disappeared six or 12 months after treatment. Glycogen particles diminished greatly during treatment. The alanine aminotransferase concentrations in these patients increased during treatment. Serum albumin and cholinesterase levels decreased significantly at the fourth week of treatment (P<0.01) and at the third day (P<0.01) to the second week (P<0.05) of treatment, respectively. These results suggest that interferon- injures endoplasmic reticulum and glycogen areas and damages the cholinesterase activity in the early stage of treatment and protein synthesis in patients with hepatitis B e antigen-positive chronic active hepatitis.  相似文献   
76.
Summary It is a clinically and experimentally well supported working hypothesis that infection with hepatitis B virus may result in chronic active hepatitis in patients with suspected immune deficiencies. On this basis, a pilot study was performed in order to evaluate the effect of specific transfer factor (TF) in the treatment of HBs-Ag-positive chronic active hepatitis. From the leukocytes of 500 ml venous blood each of 40 volunteers that had completely recovered from acute virus hepatitis B within the last 6 months, a unique TF pool (40 units of TF) was prepared according to the method of Lawrence. Preexaminations indicated that this preparation was able to enhance cellular immune reactions in vitro. Thirteen patients with HBs-antigenemia and chronic active hepatitis (i.e., two liver biopsies within the last 6 or more months with the histological criteria of chronic aggressive hepatitis according to de Groote, elevated serum levels of bilirubin, alkaline phosphatase, transaminase activities, and/or -globulines) were randomized: Seven received s.c. injections of two units of TF each on days 1 and 15, the other six saline. Conversion of skin reactions to some ubiquitous antigens occurred in the TF group, but no significant and constant drop of HBs-Ag serum titers was observed. Although some of the biochemical parameters seemed to ameliorate in the TF group, the differences versus the control group did not prove to be significant within the limited number of patients under observation. The in vitro reactivity of patients' lymphocytes to HBs-Ag, tested by means of the3H-thymidine uptake, was never found enhanced after TF application. In the used doses, specific TF was not effective in the treatment of HBs-Ag-positive chronic active hepatitis; unfavorable side-effects were not observed.  相似文献   
77.
In rodents, intracolonic administration of ethanol 30% induces an acute colitis, while administration of 2,4,6-trinitrobenzene sulphonic acid (TNBS) in ethanol induces a longer lasting colitis. In the acute and chronic stages of experimental colitis, lymphoid and non-lymphoid cells were studied in the colon by immunohistochemistry. During the acute inflammation a high damage score of the colon was observed, which was related to an increase in the number of macrophages and granulocytes. Also a change in distributional patterns of macrophage subpopulations was found. The chronic stage of TNBS-ethanol-induced colitis was characterized by an increase in the number of lymphocytes, especially T cells. These data suggest that macrophages and granulocytes are important in the acute phase of experimental colitis, while lymphocytes play a pivotal role in the chronic stage. As most inflammatory bowel disease (IBD) patients have relapses during the chronic disease, we attempted to induce a relapse during experimental colitis by giving a second i.p. or s.c. dose of TNBS. This resulted in increased damage scores of the colon, new areas of ulceration and a further increase in macrophage numbers. No effect on the number of granulocytes was seen. These results indicate that it is possible to mimic relapses in experimental colitis by a second administration of TNBS, and suggest that the rats had been sensitized by the first dose of TNBS, given into the colon.  相似文献   
78.
The aim is to compare the mean values of the in vivo electrical characteristics of bioiogical active points (BAPs) with those of the surrounding human skin. The impedance measurements at BAPs and on the surrounding skin are carried out in vivo on ten young, healthy people. The results of the measurements show that the BAP resistance RP is smaller, and the capacitance CP is higher, than the corresponding values for skin, RS and CS, respectively, these differences are larger at low frequencies (at f=3 Hz, RS/RP=3.19 and CP/CS=3.2). The mean values of the impedance measurements at the BAPs are different from those measured on the skin. The dependence of RP and CP on the pressing force, in the range of about 1–5 N, for the BAPs, has a smaller slope than that observed for the surrounding skin. An equivalent circuit for the BAPs is proposed that describes sufficiently well the experimental results obtained. These results show that the large dispersion in the observed impedance characteristics of the human body measurements in different body regions can be related to the influence of the BAPs present under the electrodes.  相似文献   
79.
Seventy five patients with acute and chronic active hepatitis (CAH) were studied by indirect immunofluorescence with monoclonal antibodies for the presence of hepatitis B surface antigen (HBsAg) on peripheral blood mononuclear cells (PBMC). The viral surface antigen was detected in the PBMC of all the patients with hepatitis B virus (HBV)-induced CAH and in acute patients with more than 2 months of evolution. No HBsAg was detected in the samples obtained from 12 normal controls or from 14 non-A, non-B CAH patients. Analysis of PBMC subsets revealed that HBsAg was present in non-T cells; dual fluorescence studies showed HBsAg on surface Ig-positive lymphocytes. The binding of anti-HBs monoclonal antibodies was higher than that of a goat anti-HBs serum, and the highest reactivity was observed with an antibody against the pre-S(2)-region sequence. Both HBsAg and hepatitis B core antigen (HBcAg) were also detected in lysates of PBMC by dot blot analysis.  相似文献   
80.
Reconstitution of functional CD4(+) T cell responsiveness to in vitro stimuli is associated with continuous highly active antiretroviral therapy (HAART). Thirty-six antiretroviral naive patients received HAART over 16 weeks. Antigen-specific, mitogen and interleukin (IL)-2 induced lymphocyte proliferative responses and specific IL-2 and IL-4 production were assessed at each time-point, together with quantification of HIV-1 RNA load and lymphocyte populations. Reconstitution of recall responses was limited largely to persistent antigens such as Herpes simplex virus and Candida, rather than to HIV-1 or neo-antigens. Recall antigens, mitogens and IL-2-induced renewed responses were associated with in-vitro production of IL-2, but not IL-4. Differential responsiveness to low versus high concentration IL-2 stimulus increases in a stepwise manner, suggesting normalization of IL-2 receptor expression and improved functionality. These increases in in-vitro proliferative responses thus probably reflect short lived effector clones, driven by ongoing antigenic stimulus associated with persisting long-term organisms. In this context non-responsiveness to HIV-1 antigens suggests ongoing HIV-1 specific clonal T cell anergy.  相似文献   
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