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91.
Activity at 5-HT1 and 5-HT2 receptor sites influences sexual behavior in male and female rats. 5-HT3 antagonists reportedly have no effect on copulatory activity in rats of either sex although they influence a variety of other behaviors. The effects of 5-HT3 agonists on sexual behavior are unknown. The following experiments were undertaken to assess the influence of the 5-HT3 agonists 1-phenylbiguanide (PBG) and 2-methyl-serotonin (2-Me-5-HT) on sexual behavior, when administered intracerebroventricularly. Consistent with earlier reports indicating that 5-HT1 and 5-HT2 receptor activity influences reproductive activity in a sex-dependent manner, PBG was found to facilitate male, but not female, rat sexual behavior. 2-Me-5-HT, however, failed to modify either female or male rat sexual activity. Evidence that PBG, but not 2-Me-5-HT, induces carrier-mediated dopamine release suggests that the effect of PBG in male rats is due to dopaminergic mediation. Overall, the present data indicate that 5-HT3 receptor activation has only slight effects on rat sexual behavior. 相似文献
92.
This experiment was undertaken to provide a pharmacological characterization of performance on a task involving food-related instrumental and consummatory behavior. Rats were tested in an operant chamber in which there was a choice between pressing a lever to receive a preferred food (Bioserve pellets) or approaching and consuming a less-preferred food (Lab Chow). The lever pressing schedule was a fixed ratio 5 (FR5). Rats usually pressed the lever at high rates to obtain the preferred food, and typically ate little of the lab chow even though it was freely available in the chamber concurrently with the lever pressing schedule. Previous work has shown that injection of dopamine (DA) antagonists, or depletion of DA in the nucleus accumbens, caused a substantial shift in behavior such that lever pressing was reduced but chow consumption increased. In the present study it was shown that the DA antagonist haloperidol decreased lever pressing and increased chow consumption at doses of 0.1 and 0.15 mg/kg. The D1 antagonist SCH 23390 (0.05, 0.1 and 0.15 mg/kg) and the non-selective DA antagonistcis-flupenthixol (0.3 and 0.45 mg/kg) decreased lever pressing and produced substantial increases in chow consumption. The D2 antagonist sulpiride decreased lever pressing, but produced only slight increases in chow intake at the highest dose. Pentobarbital reduced lever pressing and increased chow consumption at 10.0 mg/kg. The muscarinic agonist pilocarpine produced dose-related decreases in lever pressing, but failed to increase chow consumption. Amphetamine produced dose-related decreases in both lever pressing and chow consumption. These results indicate that low/moderate doses of the DA antagonists haloperidol,cis-flupenthixol and SCH 23390 can suppress lever pressing in doses that leave the animal directed towards food acquisition and consumption. 相似文献
93.
化工行业职业性机械伤害危险因素的病例-交叉方法研究 总被引:6,自引:0,他引:6
目的 研究化工行业机械伤害的有关诱发因素,估计其作用强度。方法 采用病例-交叉设计的方法。以操作和检修时受伤的化工工人为研究对象,每个对象在受伤后2d内完成调查,收集他们受伤前10min、上一工作日同一段时间和受伤前1周内有关诱发因素暴露的信息,用配对时间段方法和一般频数法进行分析,评估各种诱发因素的危险度。结果 一般频数法分析的结构表明,操作方法异常、设备工具缺陷、工作紧迫、注意力不集中、不使用防护用品、精神状况较差、与同事配合不协调、工作环境发生变化等瞬时危害因素的RR值及95%可信限的下限均大于1。配对时间段方法分析的结果与其相拟,但95%可信限较宽。结论 化工行业职业性机械伤害的发生存在着诸多诱发因素。病例-交叉研究中的一般频数法与配对时间段方法相比,前者所得结果较为可靠,研究的相对效率较高。建议进一步使用多个时间段方法进行研究,以减小混杂因素的影响。 相似文献
94.
D. Thiébaud P. Burckhardt M. Costanza D. Sloutskis D. Gilliard F. Quinodoz A.-F. Jacquet B. Burnand 《Osteoporosis international》1997,7(5):457-462
The relative importance of vitamin D deficiency, secondary hyperparathyroidism, nutritional deficiency and low bone mineral
density (BMD) as risk factors for hip fracture is not definitely established. In the framework of a case-control study of
risk factors for hip fractured, biochemical markers of bone metabolism and nutrition and femoral BMD data were compared in
136 female and 43 male hip fracture patients, 126 female and 44 male age-matched hospitalized controls, and 47 healthy elderly
women (8 men). Patients with hip fracture had lower albumin (−10%9 and 25(OH)-vitamin D (25(OH)D; −19%) compared with hospitalized
controls, and lower albumin (−28%) and 25(OH)D levels (−52%) compared with the elderly controls. Serum values of IGFBP-3 were
also significantly lower (−33%) in hip fracture patients than in community controls. BMD of femoral neck was lower (p < 0.001) in patients than in hospitalized and community controls. In hip fracture patients, parathyroid hormone (PTH) correlated
weakly with BMD (neck: r = −0.19, trochanter: r = −0.17; both p < 0.05). When all women were pooled (n = 233), albumin correlated significantly (age-adjusted) with BMD at all sites (neck: r = 0.27, trochanter: r = 0.25; all p < 0.001). Albumin, but not 25(OH)D, also correlated with skinfold thickness (r = 0.19, p < 0.0025) and with body mass index (BMI) (r = 0.14, p < 0.05). Male patients with hip fracture had lower BMD and albumin (both p < 0.001), 25(OH)D (p = 0.02) and IGFBP-3 levels (p <: 0.005) compared with the controls. When male patients and controls were pooled together, albumin, skinfold thickness and
BMI were significantly correlated with each other, but not with BMD. IGFBP-3 was highly correlated with albumin (p < 0.0001), 25(OH)D (p < 0.005) and, less significantly, with PTH (p < 0.05), but not with BMI or skinfold thickness. IGFBP-3 was significantly correlated with BMD at all sites (neck: r = 0.27, p < 0.05); trochanter: r = 0.40, p < 0.0005). In conclusion, low albumin and low BMD were both important risk factors for hip fracture. Low serum albumin was
the strongest independent variable correlated with hip fractures. In men, IGFBP-3 was correlated with BMD. The femoral BMD
depended only weakly on PTH and 25(OH)D, but was correlated at all sites with albumin, a non-specific parameter of nutrition
and general health. 相似文献
95.
The treatment of neoplasia with interleukin-2 (IL-2) can be complicated by neurological deficits resembling transient Ischemic attack and stroke. We investigated whether interleukin-2 contributes to the natural course of cerebrovascular ischemia and particularly to the pathogenesis of infection-associated stroke. Plasma levels of interleukin-2 were below the level of detectability in almost all measurements. Patients with and without previous infection (n = 11, 805 ±445 U/ml vs n = 19, 824 ± 501 U/ml) did not have significantly higher levels of soluble interleukin-2 receptors than control subjects with (n = 14, 667 ± 229 U/ml) or without vascular risk factors (n = 17, 567 ± 176 U/ml). Receptor levels increased in patients during the first week after stroke (n = 15, 1157 ± 1013, p < 0.02). Levels of soluble T8 antigen (sT8) were higher in patients (n – 26, 320 ± 112 U/ml) than in healthy control subjects (n = 15, 246 ± 92 U/ml; p < 0.05) and sT8 levels increased during the first week after stroke (p < 0.05). These results reflect an immunological response to the cerebral infarct; they do not indicate a general role of the IL-2 system in the pathogenesis of ischemic stroke with or without previous infection. 相似文献
96.
Reyna O. Calderon B. Maggio T. J. Neuberger G. H. Devries 《Journal of neuroscience research》1993,34(2):206-218
The axolemma membrane forms a stable and reproducible monomolecular layer at the air-aqueous interface. The major lipids and proteins are present in this monolayer in molar ratios similar to the original membrane. Acetylcholinesterase and Na-K-ATPase activities are preserved in the monolayer to levels of 64% and 25%, respectively. The total lipid fraction forms a homogeneously mixed phase. The presence of proteins in the monolayer introduces surface inhomogeneties. Among other features, this is revealed by the presence of two values of lateral pressure at which the monolayer shows partial or total collapse: a broad partial collapse at surface pressures between 13 to 30 mN/m and a sharp collapse point at 46 mN/m. The average molecular areas, the broad collapse point, and the variation of the surface potential per molecule suggest the relocation of protein components at surface pressures between 13 to 30 mN/m. The behavior is consistent with the extrusion and exposure of proteins toward the aqueous medium that depends on the lateral pressure. Schwann cells grown on coverslips coated with axolemma monolayers at 13 mN/m (beginning of the broad collapse) and 34 mN/m (above the broad collapse) recognize the difference in the surface organization of axolemma caused by the lateral pressure which affects their proliferation, morphology, and spatial pattern of organization. Our results show for the first time that response of Schwann cells depends on the intermolecular organization of the axolemma surface with which they interact. These results suggest that the local expression of putative surface molecules of axolemma that may mediate membrane recognition and the signalling of morphological and proliferative changes can be modulated by long range supramolecular properties. © 1993 Wiley-Liss, Inc. 相似文献
97.
Bo Sikström M.D. Dan Hellberg M.D. Ph.D. Staffan Nilsson M.D. Ph.D. Christina Brihmer M.D. Ph.D. Per-Anders Mårdh M.D. Ph.D. 《Archives of sexual behavior》1996,25(4):361-372
In a study of 972 women, sexual characteristics of 66 women with a cervical human papillomavirus infection (CHPI) were compared
to the remaining study population. Among a number of sexual variables that were significantly correlated with CHPI were number
of lifetime sexual partners, short partnerships, many recent partners, infidelity, casual travel sex, sexual début abroad,
oral and anal sex, and sexual abuse. In multifactorial analyses four variables remained significantly correlated with CHPI,
i.e., number of lifetime sexual partners, casual travel sex, sexual début abroad, and infidelity. It is concluded that CHPI
shows most of the epidemiological characteristics of a sexually transmitted disease. 相似文献
98.
Yukio Fukuyama Tohru Seki Chikaya Ohtsuka Hisao Miura Michiko Hara 《Brain & development》1996,18(6):144-484
Recent studies have shown that adequate medication can prevent the recurrence of febrile seizures (FS). It has also been clarified that the vast majority of, though not all, FS patients follow a benign course. Then, questions arise as to whether or not FS should be prevented, particularly in light of the risks of side effects from drugs. Which kinds of FS can be prevented, if necessary? The guidelines presented here are aimed primarily at helping general practitioners in considering how to manage FS most appropriately. The guidelines stress that judgements should be individualized, while referring to a few specific ‘warning factors’. The guidelines follow a ‘laissez-faire’ principle for the majority of FS cases, whereas intermittent therapy with diazepam and continuous medication with either phenobarbital or valproate are indicated in other limited cases meeting respective definite criteria. 相似文献
99.
目的 评价直接置入药物洗脱支架 (CYPHERTM,codis)在A或B1 型病变的冠心病患者治疗中的安全性、可行性。方法 6 2例接受CYPHERTM 支架直接置入的患者 (直接支架组 )和一般情况匹配的 5 1例球囊扩张后行冠脉支架术的患者 (常规支架组 ) ,比较两组的一般情况 ,冠脉造影及介入治疗即刻和临床随访结果。结果 直接支架组介入操作时间明显短于常规支架组 [(17.2± 8.6 )比 (2 6 .3± 7.1)min ,P <0 .0 1],直接支架组平均扩张压明显高于常规支架组 [(14± 3)比 (12± 1.9)atm ,P<0 .0 1],两组无一例发生介入治疗相关的严重心脏事件。随访期间两组严重心脏不良事件发生率无显著差异。结论 A或B1 型病变的冠心病患者CYPHERTM 支架直接置入术可缩短介入操作时间 ,即刻效果、并发症及中期临床随访与常规支架组差异无显著性意义 相似文献
100.
目的 了解本社区高血压患者的危险因素现状,探讨干预对策。方法 采用分层整群抽样的方法,随机抽取社区4个里委2级、3级高血压患者402例作为研究对象,收集各项危险因素如性别、年龄、血脂、血糖、吸烟、饮食、体育锻炼、体重等,并进行统计分析。结果402例高血压患者1年内进行所有相关辅助检查者有14例,占3.48%;1年内进行相关辅助检查一项者306例,占76.12%。饮食控制及进行体育锻炼有300例,占74.43%;吸烟62例,占15.42%。结论 高血压患者对饮食控制及体育锻炼、吸烟有害的知晓率明显提高,而对相关辅助检查认识不足。 相似文献