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31.
肺炎患儿白细胞变形能力和粘附功能的变化及临床意义   总被引:1,自引:2,他引:1  
肺炎患儿白细胞变形能力和粘附功能的变化及临床意义林荣军1刘成玉2潘玉娟3徐丽园研究表明,白细胞与急性肺组织损伤有密切关系[1],白细胞在肺内聚集是产生急性肺损伤的重要环节,而细胞粘附分子(cAms)介导的各种白细胞的粘附,特别是中性粒细胞粘附和跨膜转...  相似文献   
32.
The geroprotector activity of epitalon, a synthetic tetrapeptide Ala–Glu–Asp–Gly, was studied on the Drosophila melanogaster wild strain Canton-S. The substance was added to the culture medium only at the developmental stage (from egg to larva). Epitalon significantly increased the lifespan (LS) of imagoes by 11–16% when applied at unprecedented low concentrations — from 0.001×10–6 to 5×10–6 wt.% of culture medium for males and from 0.01×10–6 to 0.1×10–6 wt.% of culture medium for females. The increase in LS did not depend on the substance dose. Effective concentrations of epitalon were 16 000–80 000 000 times lower than those of melatonin. The possible mechanisms of the antioxidant and regulatory effects of epitalon are discussed.  相似文献   
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目的探讨前列腺液白细胞含量与精液主要参数和指标的关系。方法对入选的260例男性不育患者进行前列腺液(EPS)常规检查计数白细胞和解脲支原体培养,按照WHO人类精液实验室手册要求检测精液主要参数、精子形态分析、精子顶体酶活性、精浆抗体(AsAb)等,分析前列腺白细胞与男性不育相关因素的关系。结果260例中炎症组93例(EPS中WBC≥10个/HP):非炎症组(EPS中WBC〈10个/HP)167例。炎症组精液的精子密度、精子活动率、a+b级活力精子率、精子顶体酶阳性率均低于非炎症组(P〈0.05);而精液液化时间、精子畸形率、精浆抗体(AsAb)、前列腺液解脲支原体阳性率高于非炎症组(P〈0.05)。两组的精液量及pH值差异无显著性。结论前列腺液中白细胞含量对精液质量有一定的影响,慢性前列腺炎是导致男性不育的原因之一。  相似文献   
35.
目的为了研究细菌性腹膜炎时经腹腔蛋白质丢失的机制,阐明白细胞移行与蛋白质丢失的关系。方法给兔腹腔内注射大肠杆菌(E.coil)4×106CFU+生理盐水(35ml/kg),做成急性腹膜炎动物模型。通过测定实验6或8h期间腹透液中白细胞总数(WBC)及中性粒细胞(PMNs)计数情况以及腹膜对蛋白质的通透性(蛋白质D/P比值)。设立了两个系列的实验系列一,应用氮介(mustine),1.2mg/kg,实验前3天静脉注射,以耗尽循环血中的白细胞;系列二,用单克隆抗体(mAb)60.32mg/kg,实验前5min静脉注射,以阻滞PMNs上的粘附分子CD18,从而抑制PMNs向腹腔移行。同时设立了阳性对照组(即腹膜炎组)及阴性对照组(无腹膜炎组)。结果系列一中mustine降低87%循环血中白细胞及93%循环血中PMNs,此时即使腹腔内注射细菌,白细胞向腹腔的移行及腹腔蛋白质的渗出均较未注射mustine的腹膜炎组明显降低,而与无腹膜炎的正常对照组结果相似。系列二,静脉注射mAb60.3同样也明显降低白细胞及PMNs向腹腔的移行及经腹腔蛋白质的丢失。结论急性细菌性腹膜炎时白细胞向腹腔移行导致了经腹腔蛋白质的丢失。  相似文献   
36.
为了探讨缺氧,缺血及再灌注损伤的发生的机制,我们分别观察了缺氧(模拟海拔4000m高原)24h山羊血浆(HP),缺血1h(在上述条件下于缺氧24h末放血使血压维持在6.0kPa1h)山羊血浆(IP)和再灌注回输放出血液后24h)山羊血浆(RP)对中性粒细胞(PMN)及培养的肺动脉内皮细胞(PAEC)的作用,PMN在分别含HP、IP和RP的培养中温育1h末,细胞活力明显升高(P〈0.001),其升高  相似文献   
37.
The purpose of this double-blind, placebo-controlled study was to determine and compare the clinical efficacy and tolerance of human leukocyte -interferon (incorporated 2 × 106 IU/g) in hydrophilic cream to cure genital warts. Preselected Asian female patients (n=150) aged 18–40 years (mean 22.5), with the clinical and biopsy-confirmed diagnosis of genital warts (mean 2.64), predominantly flat vaginal condylomas, were randomly allocated to 3 parallel groups. Each patient was given a coded tube containing 80 g placebo/active preparation with a graduated applicator. Patients were instructed to inject 6 g of the either alloted placebo/active cream deep into the vagina thrice a day for 3 consecutive days (group A) or 4 consecutive days (group B) per week, and if not cured the same treatment was extended to 3 more weeks (maximum 4 weeks active treatment). To assess the clinical efficacy patients were examined on a week-to-week basis. A total clearance of warts (biopsy-confirmed) was evaluated as a complete cure. Patients cured during the treatment were spared further treatment and were requested to visit us after 16 weeks for relapse control. As for the remaining patients, empty tubes were collected, and similarly coded replacement tubes were given for further treatment (in total 588 tubes were used). By the end of the treatment 57.2% lesions (227/397) were eliminated in all the groups: 48% patients in group A, 90% patients in group B, and 10% patients in placebo groups taken as completely cured. Of the 150 patients 128 (85.3%) did not complain of any drug-related adverse symptoms. Transitory increase in body temperature (mean 38.4°C), accompanied by headache (14.6%) and generalized itching (6.6%) were the most frequently reported side effects; however, treatment was well tolerated by all the patients, and there were no dropouts. Our findings indicate that clinical efficacy is dose dependent, that is, the results of group B were significantly superior to that of group A (P < 0.05). Of the 49.3% cured patients (74/150) followed up for 6 months (monthly basis) seven had a relapse, and none had reinfection. It is concluded that clinical efficacy of leukocyte interferon-a to cure genital warts is dose dependent. These results further support the view that leukocyte interferon-a incorporated in hydrophilic cream can be considered a reliable, safe, and home-based treatment to cure vulvar and vaginal warts.Abbreviation HPV human papillomavirus  相似文献   
38.
为研究急性坏死性胰腺炎(ANP)早期白细胞粘附强弱和肿瘤坏死因子(TNF)的变化及其与肺损伤的关系,以及大承气汤能否减轻肺损伤的程度,将14 只家犬随机分成承气汤组(n= 5,ANP模型+ 大承气汤治疗),盐水组(n= 5,ANP模型+ 生理盐水治疗)和假手术组(n= 4)3 组。术后在流室系统下观察白细胞与内皮细胞的粘附强弱,并测定血清及支气管肺泡灌洗液(BALF)TNF活性和肺损伤程度。结果显示:实验犬ANP时白细胞粘附活性增强,外周血及BALF中TNF活性升高;承气汤组白细胞粘附活性低于盐水组(P< 0.05),血清及BALF的TNF活性低于盐水组(P< 0.01);承气汤组肺损伤程度轻于盐水组。结果提示:白细胞粘附和TNF的过度分泌参与ANP病理生理及肺损伤的发生,大承气汤能够减轻二者介导的肺损伤。  相似文献   
39.
To study the effect of moderately elevated gonadotrophin releasinghormone (GnRH) baseline concentrations during the luteal andthe follicular phase, pseudopregnant rats were infused s.c withGnRH at several doses for 5 days. These rats were also treatedwith oestradiol or sham-treated during the last 3 days of GnRHtreatment GnRH infusions started on day 7 or day 3 of the lutealphase of the ovulatory cycle; in the rat, the luteal phase orpseudopregnancy lasts about 10 days. Luteinizing hormone (LH)and follicle stimulating hormone (FSH) responses were inducedby i.v. injection of GnRH on day 12 (after expected luteolysis)or on day 8 (before expected luteolysis). In normal rats theLH and FSH responses induced by GnRH on day 12 were higher thanon day 8 (160 and 50% respectively). In GnRH-infused rats theLH and FSH responses were not increased. In these rats the lutealphase was extended (the plasma progesterone concentrations remainedhigh) and the onset of the follicular phase was postponed (plasmaoestrogen concentrations did not increase). Oestradiol increasedthe day 12 LH and FSH responses; this effect of oestradiol wassuppressed by GnRH infusion. On day 8, exogenous oestradiolalso increased the LH and FSH responses, but again the effectof oestradiol was suppressed when the animals were concomitantlyinfused with GnRH. These data may suggest that in the rat, GnRHbaseline concentrations participate in the neuroendocrine systemcontrolling gonadotrophin secretion and hence the ovulatorycycle.  相似文献   
40.
Anti-CD3 antibodies induce a quick and profound depletion of peripheral blood mononuclear cells (PBMCs) that is not well understood. We studied the effect of OKT3, a mouse monoclonal antibody againts the human CD3 complex, on the in vitro adhesion of human PBMCs to monolayers of fresh and fixed human umbilical vein endothelial cells (HUVECs). OKT3 induced an increased adhesiveness of PBMCs. This phenomenon was blocked with anti-CD18 antibodies, indicating the participation of 2 integrins. As this increased adhesiveness could explain the lymphopenia by adhesion of PBMCs to endothelial cells and their sequestration in some peripheral vascular beds, we studied the effect of anti-CD18 antibodies in vivo on mice injected with 145/2C11, a hamster monoclonal antibody against murine CD3. Mice treated with 145/2C11 presented with a transient granulocytopenia and a sustained reduction in PBMCs. A monoclonal anti-CD18 antibody prevented the granulocytopenia but had no effect the drop in PBMCs. Consequently, the in vivo depletion of PBMCs after administration of an anti-CD3 monoclonal antibody involves CD18-independent mechanisms, while the transient drop in polymorphonuclear cells appears to be CD18-dependent.  相似文献   
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