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41.
Adult rats emit 22 kHz ultrasonic vocalizations (USVs) in response to aversive stimuli, and these sounds are suggested to have communicative information among conspecifics. It is conceivable that social environment during development of rats has relevance to the emission of 22 kHz USVs. To examine the effects of social environment after weaning on production of stress-induced USVs, we compared the amount of emission of USVs among three groups of rats reared under different conditions after weaning. One group of rats was housed individually, and the other two groups were housed in pairs, in which social hierarchy of the pair was determined by social dominance-subordination relationships. The USVs were induced by acute mild somatic stimuli on the back and neck. Individually reared rats emitted much fewer USVs than pair-reared rats. In addition, socially subordinate rats emitted more USVs compared with socially dominant ones. These results suggest that not only social interaction but also the status in social hierarchy may play an important role in the process of the development of USVs induced by somatic stimuli. 相似文献
42.
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
43.
Clinical, parasitological and immunological features of canal cleaners hyper-exposed to Schistosoma mansoni in the Sudan
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M Z SATTI S M SULAIMAN M M A HOMEIDA S A YOUNIS H W GHALIB 《Clinical and experimental immunology》1996,104(3):426-431
The present work was a longitudinal study on Schistosoma mansoni infection in occupationally hyperexposed canal cleaners in the Sudan and the influence of therapy on the parasitological and humoral immune parameters. Chronically infected canal cleaners (n = 28) were more resistant to reinfection (Fisher's exact test, P < 0.05) than newly recruited canal cleaners (n = 17). Chronically infected canal cleaners had a significantly higher degree of Symmers' fibrosis (χ2 = 19.1, P < 0.0001), significantly larger portal vein diameter (P < 0.05) and enlarged spleen (χ2 = 4.2, P < 0.05) than recently infected, newly recruited canal cleaners. ELISA was used to detect IgG, IgA and IgM in response to whole worm homogenate (WWH) and cercarial homogenate (CH). Chronically infected canal cleaners had significantly higher IgG to WWH antigen than newly recruited canal cleaners and normally exposed individuals (P < 0.05), while both chronically infected and newly recruited canal cleaners had higher IgG levels to CH antigen than normally exposed individuals (P < 0.05). The newly recruited canal cleaners had a significantly higher IgM level to CH antigen than chronically infected canal cleaners (P < 0.05). The IgG level to WWH antigen increased significantly after treatment in newly recruited canal cleaners and normally exposed individuals (P < 0.05). The IgA level to CH antigen increased significantly after treatment in the chronically infected group (P < 0.05). Comparison of the serological parameters between the different study groups with regards to infection and treatment is discussed. 相似文献
44.
Behavioral and neurochemical effects induced by subchronic combined exposure to toluene at 40 ppm and noise at 80 dB-A in rats 总被引:1,自引:0,他引:1
We investigated whether exposure to noise, in addition to its well-known potentiating effect on toluene-induced ototoxicity, may also exacerbate behavioral disturbances and brain neurochemical alterations produced by subchronic exposure to low toluene concentration. To test this hypothesis, we evaluated whether subchronic combined exposure (16 weeks, 104 h per week) to noise at 80 dB-A and toluene at 40 ppm potentiates the recently reported neurotoxic effects of subchronic exposure to 40 ppm toluene. Locomotor and rearing activities, sensitization to narcosis induced by acute toluene at high concentration, and tyrosine and tryptophan hydroxylase activities in the caudate-putamen and hippocampus were investigated in both male and female rats. Our results confirm that subchronic exposure to 40 ppm toluene significantly decreases rearing activity and leads to a sensitization to toluene-induced narcosis, as evaluated by loss of righting reflex, but fails to demonstrate any adverse effect of noise, alone or in combination with toluene. Given that toluene has addictive properties, the lack of potentiating behavioral and neurochemical effect of noise is discussed with regards to a recent study that has shown that methamphetamine neurotoxicity is potentiated by exposure to loud noise. 相似文献
45.
Summary Testicular spermatozoa are functionally immature in that they cannot fertilize ova. It was first demonstrated by Young [171, 172] that spermatozoa undergo certain changes as they migrate through the epididymis. He proposed that spermatozoa ripen during epididymal transit. It is now known that specific maturational changes occur in spermatozoa during epididymal transit which result in their developing the ability to fertilize ova. Concomitant with this functional maturity are changes in spermatozoal morphology, motility, chemistry, permeability, density and metabolism. It is apparent that in some way not understood these changes are necessary for sperm to achieve the ability to complete the fertilization process. When these mechanisms are understood, we may be able to effectively treat conditions such as necrospermia or abnormally low sperm motility. Furthermore, with the development of the hamster-egg penetration test a new type of male infertility has become evident in recent years; the inability of otherwise normal sperm to penetrate an ovum. It is during epididymal transit that this ability is normally acquired. Thus, any insight into how sperm attain the capacity to penetrate an ovum could lead to an effective treatment of patients whose sperm do not have this ability. In addition, the epididymis holds significant promise as the site of action for a male contraceptive. Thus, it is the purpose of this review to describe the structure and function of the mammalian epididymis with particular emphasis on the factors regulating sperm maturation. 相似文献
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目的 通过已建立的小鼠睾丸体外培养系统,研究四种内分泌干扰物(Endocrine Disrupting Chemicals,EDCs)对男性内分泌系统的影响。 方法 将新生小鼠的睾丸组织在体外环境中培养24h,而后在培养基中分别加入浓度为0.1μM, 1μM, 10μM and 100μM的四种(DEHP、MEHP、NP、p, p’-DDE)内分泌干扰物并培养72h,同时设置对照组;培养结束后进行组织学观察,测定冻存培养基中睾酮和抑制素βB (INH-βB)的分泌水平,同时测定细胞色素P450侧链裂解酶(P450Scc)、3β-羟基类固醇脱氢酶(3β-HSD)、细胞色素P45017α-羟化酶(P450C17)和波形蛋白(vimentin)的基因表达情况。 结果 所有剂量组中睾酮的分泌水平均发生改变;P450Scc、3β-HSD、P450C17和INH-βB蛋白质的表达及mRNA水平均受到四种内分泌干扰物的影响(P<0.05);DEHP和MEHP降低了波形蛋白的mRNA水平(P<0.05),而NP和p, p’-DDE对波形蛋白没有显著影响(P>0.05)。 结论 本研究建立的体外培养新生小鼠睾丸模型中,所选的四种已知EDCs改变了两种睾丸激素水平,三种类固醇合成酶以及与支持细胞功能相关的波形蛋白的表达。 相似文献
48.
中国男性新兵MMPI测查结果与分析 总被引:15,自引:1,他引:15
协作组对来自21个省、自治区的男性汉族新兵进行MMPI测查,并与中国男性、16~25岁组及中学学历组常模进行比较,发现①中国男性新兵有紧张、焦虑、情绪不稳、易激惹,夸张或表现自己,强迫思维或强迫行为,或为兴趣狭窄、自责、过分关心自身健康或有较多躯体不适等心理卫生问题;②外向性和神经症性的个性倾向较突出;③新兵组的Hs、Pa、Pt、Ma分均值显著高于常模组,Mf、Si、D、Pd、Sc分均值显著低于常模组。提示部队的心理卫生工作应始于新兵入伍时。 相似文献
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50.
《Journal of pediatric urology》2022,18(2):236.e1-236.e7