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81.
糖尿病雄性大鼠性腺5α-还原酶Ⅱ型活性变化 总被引:5,自引:0,他引:5
目的 :探讨大鼠青春期和成年期糖尿病时性腺 5α 还原酶Ⅱ型的活性变化。 方法 :取 4 0d和 90d龄雄性Wistar大鼠各 30只 ,分别分为对照组 (C)、糖尿病组 (D)和胰岛素治疗糖尿病组 (ID)。采用薄层层析法测定各组附睾头、附睾尾、前列腺和睾丸组织内 5α 还原酶 Ⅱ型的活性。 结果 :①青春期大鼠性腺的各部位内 ,5α 还原酶 Ⅱ 型的活性D组均明显低于C组 (P <0 .0 1) ,而ID组明显高于D组 (P <0 .0 1) ;②成年期大鼠性腺的各部位内 ,5α 还原酶 Ⅱ型的活性在C、D和ID组各组间差异无显著性 (P均 >0 .0 5 )。 结论 :青春期大鼠性腺内 5α 还原酶 Ⅱ型的活性更易受代谢环境、激素水平及局部特异性因素的影响 ,而成年期大鼠性腺内 5α 还原酶Ⅱ 型的活性相对稳定 相似文献
82.
Josef Parvizi Jeffrey Joseph Daniel Z Press Jeremy D Schmahmann 《Movement disorders》2007,22(6):798-803
In the cerebellar type of multiple system atrophy (MSA-C), the burden of pathological changes involves the cerebellum and its associated brainstem structures in the basis pontis and the inferior olivary nucleus, and as a result, the clinical phenotype is dominated early on by the cerebellar dysfunction. We report our clinical and post mortem findings in a patient with MSA-C who exhibited pathological laughter in the absence of any congruent changes of mood. A review of the clinical notes of 27 other patients with MSA-C revealed a problem with pathological laughter, or crying, or both in 9 more patients. Our finding of about 36% occurrence suggests that the problem of dysregulation of emotional expression is more prevalent in MSA-C than the paucity of reports in the literature suggests. Our findings are consistent with the view that the cerebellum and its interconnected structures may be involved in the regulation of emotional expression. 相似文献
83.
目的:了解性病患者对安全性行为知识的知晓情况。方法:采用问卷方式对256例性病门诊患者进行安全套问题调查,并对所得数据进行统计分析。结果:从不使用安全套患者由初诊117例(45.7%)降到复诊时86例(33.6%);得知自己患性病后不用安全套与他人性交初诊118例(46.1%)下降到复诊时97例(37%);不用安全套与无性病症状的人性交会否感染性病回答不知道的由初诊58例(22.7%)下降到复诊时14例(5.5%)。结论:加大提倡使用安全套的宣传力度,提高人们对安全性行为的认识水平,提高安全套的使用率,是控制和预防性病及爱滋病经性接触传播流行的关键。 相似文献
84.
目的 观察行为干预对慢性乙型肝炎患者健康行为的影响。方法 将300例慢性乙型肝炎患者作为目标人群进行健康教育,建立目标人群管理档案,进行目标人群健康行为干预,比较教育前后相关行为的改变。结果 慢性乙型肝炎患者8项健康行为和8项危险健康行为有明显改观,差异具有统计学意义(P〈0.01)。结论 通过行为干预,有效地使慢性乙型肝炎患者完全遵从医嘱合理用药,完全依从健康行为,从而减少危险行为的发生。 相似文献
85.
Endogenous opioid-immunoreactive neurons of the ventromedial hypothalamic nucleus concentrate estrogen in male and female rats 总被引:1,自引:0,他引:1
Estrogen stimulates expression of proenkephalin mRNA in neurons of the hypothalamic ventromedial nucleus, and evidence is accumulating that synaptic release of one of the peptide end products, met-enkephalin, influences events that regulate reproductive behavior. To address the question of whether estrogen acts directly on neurons that synthesize met-enkephalin or indirectly through a separate neuronal population, we combined estrogen autoradiography with endogenous opioid peptide (EOP) immunohistochemistry. In agreement with previous studies, the ventrolateral subdivision of the hypothalamic ventromedial nucleus was densely packed with EOP-immunoreactive cells. In males, 48% of the estrogen-concentrating cells of the ventrolateral subdivision of the hypothalamic ventromedial nucleus contained EOP, and, in females, 27% of the estrogen-concentrating cells contained EOP. These findings indicate that estrogen acts directly on neurons that express EOP and suggest a mechanism that underlies sexually differentiated reproductive behavior. 相似文献
86.
东莞市正常儿童头发中微量元素含量参考值的研究 总被引:1,自引:0,他引:1
目的探讨东莞市区幼儿园3~7岁学龄前正常儿童头发中微量元素含量均值,以此作为东莞市区儿童头发中微量元素正常参考值.方法采取在群体自愿参加者中,选出经体检无重要脏器病变,营养一般,身高、体重在均值以上(称正常儿童).在枕后贴发根部剪0.5g头发检测其锌、铁、钙、铜、锰、铅元素含量.结果在1125例受检儿童中(称普查儿,占适龄儿95%).筛选出621例儿童,占总受检儿童的55.2%.这621例正常儿中,他们头发中锌、铁、钙、铜、锰、铅元素的含量分别为:93.473μg/g、29.710μg/g、779.50μg/g、9.773μg/g、3.222μg/g、9.251μg/g.结论检测的结果显示,2003年东莞市区正常儿童与2003年普查儿童相比,正常儿童发中微量元素含量明显升高,但差异无统计学意义.2003年东莞市正常儿童发中微量元素均值与广州市正常儿童相比,显著低于广州市正常儿童.由此可见,正常儿童发中微量元素含量均值受地域影响而有较大差异.东莞市区儿童发中微量元素含量应参照东莞市正常儿童发中微量元素含量均值较为合理. 相似文献
87.
目的:探讨前列腺基质增生的发病机制与性激素以及相关生长因子的关系。方法:应用RT-PCR的方法研究了在人前列腺不同细胞类型中Smoothelin的表达,研究了雄、雌激素受体及相关生长因子在前列腺基质细胞中的表达,以及它们在前列腺基质细胞分化中表达的变化。结果:Smoothelin是前列腺平滑肌细胞特异性的标记蛋白;雄激素受体(AR)、碱性成纤维细胞生长因子(bFGF)、角化细胞生长因子(KGF)主要在前列腺成纤维细胞中表达,而雌激素受体(ER)、转移生长因子β1(TGFβ1)主要在平滑肌细胞中表达。结论:前列腺基质增生与雌激素受体和转移生长因子β1的过度表达密切相关。 相似文献
88.
We review evidence that schedule-controlled intracranial self-stimulation (ICSS) has properties in common with conventional reinforcements, such as food and water, but unlike the latter, animals will respond for ICSS for long periods of time at a near-constant rate. Schedule-controlled ICSS has proven to be more sensitive to drug-induced changes than has ICSS on a continuous reinforcement schedule, and it permits a more fine-grained analysis of the pattern of responding that results in the reinforcement. Evidence is accumulating that the schedule of ICSS itself leads to neurochemical changes in areas of the brain, such as the nucleus accumbens, in which reward processes occur. Results obtained from schedule-controlled ICSS would complement those obtained by drug self-administration studies which generally use intermittent reinforcement. A systematic examination of ICSS schedules at different brain sites would greatly facilitate our interpretation of drug effects and this would have utility for behavioral pharmacology. 相似文献
89.
C. Gupta 《Urological research》1997,25(4):277-281
Previous studies from this laboratory indicated a role for epidermal growth factor (EGF) in androgen-dependent male reproductive tract differentiation of the fetal mouse. Expression of an EGF-like protein during Wolffian duct differentiation was indicated from the determinations by radioimmunoassay (RIA) and radioreceptor assay. To further characterize the protein and to assess its role in male sexual differentiation, expression of the protein has been analyzed by Western blot assay and its tissue-specific cellular expression has been determined by immunocytochemical assay in the present study. Western blot analysis of the 18-day fetal male reproductive tract detected an immunoreactive band of the predicted 6-kDa size. Immunocytochemical analysis also detected EGF-specific immunostaining in the Wolffian duct derivatives. At day 18 of gestation, the staining was localized predominantly in the epithelial nuclei of the Wolffian duct derivatives whereas at days 14 and 16 of gestation, the staining was equally distributed in the mesenchymal and epithelial sites of the Wolffian duct derivative. The intensity of the staining increased with progression of differentiation during the 14th–18th days of gestation. Prenatal exposure to the antiandrogen flutamide significantly reduced the immunostaining of the duct. Thus, a role for EGF in Wolffian duct differentiation is indicated. 相似文献
90.
Henryk Barthel Michael Wiener Claudia Dannenberg Simone Bettin Bernhard Sattler Wolfram H. Knapp 《European journal of nuclear medicine and molecular imaging》1997,24(10):1245-1252
This study addresses the question of whether the normal range for distribution of local cerebral blood flow (lCBF) in adults
can be transferred to the 4- to 15-year-old age group. Twenty-three children (age: 4–15 years; mean 11±3 years, group I) and
10 adults (age: 27–56 years; mean 45±10 years, group II) without evidence of cerebrovascular disease or other brain diseases
underwent technetium-99m ethyl cysteinate dimer single-photon emission tomography. Counts in cortical and subcortical regions
of interest (ROIs) were related to those in cerebellar ROIs (= 100%). Relative cortical activity in group I exceeded that
in group II, particularly in left parietal (107.6%±9.8% vs 84.1%±12.4%), left frontal (97.7%±6.7% vs 79.4%±8.9%) and left
temporal areas (99.7%±7.4% vs 84.9%±10.1%) and in the cingulate cortex (112.1%±9.1% vs 95.9%±10.1%, P<0.05). Cerebral activity uptake per injected dose was inversely correlated with age in 19 children of group I (r = –0.77, P<0.001). In group I, there was also an inverse correlation between age and the relative local count density in the parietal
(r = –0.42 to –0.57), frontal (r = –0.48), temporal (r = –0.42 to –0.58) and occipital cortex (r = –0.44). In these cortical regions relative counts differed when subgroups of children aged 4–10 and 11–15 years were analysed.
It is concluded that there are systematic differences between 4- to 15-year-old children and adults with regard to normal
lCBF. Diagnostic use of perfusion agents has to consider age-adjusted normal flow maps; normal ranges should be determined
separately for the age groups 4–10 and 11–15 years.
Received 23 March and in revised form 11 July 1997 相似文献