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151.
目的研究引起安氏Ⅲ类错牙合畸形的病因。方法对50例安氏Ⅲ类错牙合患者和50例正常牙合人作病因问卷调查,将结果用logistic法分析,提取有效病因。结果共有慢性扁桃体炎、遗传因素、咬上唇3项病因进入方程。结论按贡献大小,长期慢性扁桃体炎、经常咬上唇和遗传因素是导致安氏Ⅲ类错牙合畸形的危险因素。 相似文献
152.
Many epidemiological studies have shown the magnitude and seriousness of mental disorders in developing countries. However, mental health care remains unsatisfactory owing to lack of skilled manpower and many other social and medical priorities. General practitioners and other health personnel can significantly help in extending mental health care provided they receive adequate training during their medical curriculum. With this aim, the Department of Psychiatry at Addis Ababa University runs a 6-week full-time course for undergraduate medical students. Its chief objectives, teaching methods, achievements and shortcomings are discussed in the paper. 相似文献
153.
154.
Correlation between 5-HT7 receptor affinity and protection against sound-induced seizures in DBA/2J mice 总被引:2,自引:0,他引:2
Anne Bourson Véronique Kapps Catherine Zwingelstein Alain Rudler Frank G. Boess A. J. Sleight 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(6):820-826
Audiogenic seizures can be induced in DBA/2J mice following intense auditory stimulation. A number of neurotransmitters, including
5-hydroxytryptamine (5-HT), are believed to be involved in mediating this effect since it has been shown previously that depletion
of 5-HT or blockade of 5-HT receptors protects DBA/2J mice from these audiogenic seizures. The present study was undertaken
to determine whether antagonism of the newly identified 5-HT7 receptor may protect DBA/2J mice from audiogenic seizures by attempting to correlate in vivo potency of compounds with their
affinity at the 5-HT7 receptor. All compounds used in the correlation were shown to be antagonists at the 5-HT7 receptor and a statistically significant correlation was observed between 5-HT7 affinity and doses for half-maximal response (ED50) for protection of DBA/2J mice from sound-induced seizures (r = 0.80; P < 0.05). No significant correlation was observed between in vivo activity and affinity at either 5-HT1A, 5-HT2A or 5-HT2C receptors. It is also unlikely that interactions between the 5-ht5 receptor will protect DBA/2J mice from audiogenic seizures since metergoline and mesulergine which are both active in this
in vivo model have no affinity for the 5-ht5 receptor. There are similarities between the pharmacology of the 5-HT7 receptor and that of the 5-HT1A receptor, however the correlation between the in vivo potency in DBA/2J mice and 5-HT1A affinity was not significant. Furthermore, the 5-HT1A receptor antagonist WAY 100135 did not protect DBA/2J mice from audiogenic seizures at doses that antagonise 5-HT1A receptor-mediated effects in mice. These data suggest that antagonism of 5-HT7 receptors may protect against audiogenic seizures in DBA/2J mice although a definitive conclusion must await studies with
selective 5-HT7 antagonists.
Received: 20 March 1997 / Accepted: 10 August 1997 相似文献
155.
特异性荧光偏振免疫法监测521例肾移植后环孢素A全血浓度3275次 总被引:2,自引:0,他引:2
目的通过监测肾移植后病人环孢素A(CsA)全血浓度 ,提出CsA在三联免疫抑制用药方案中的理想治疗窗。方法用特异性荧光偏振免疫法测定CsA全血浓度 ,对521例病人监测3275次 ,按术后时间及临床表现分组比较。结果肾移植后<1 ,、1~3、3~6、6~12个月、1~2和>2年的CsA全血谷浓度的理想治疗窗应分别为250~450、200~400、150~300、100~250、100~200和100~180μg/L。结论CsA全血浓度在上述范围内 ,中毒反应和排异反应明显减少 相似文献
156.
维甲酸硅油的视网膜毒性实验研究 总被引:1,自引:0,他引:1
目的:了解维甲酸硅油对视网膜是否产生毒性。
方法:12只新西兰白兔的24只眼,随机分为3组,行气体压迫玻璃体手术3天后,分别向玻璃体腔内注入硅油(4只眼)、5μg/ml维甲酸硅油(10只眼)、10μg/ml维甲酸硅油(10只眼)各
0.5m1,用检眼镜、光漳和电镜检查来观察视网膜变化情况。
结果:注入硅油28天后,未发现各浓度的维甲酸硅油对视网膜产生毒性作用。结论:浓度为5、10μg/ml的维甲酸硅油注入玻璃体腔4周,对视网膜不产生毒性作用。
(中华眼底病杂志,1997,13:81-82) 相似文献
157.
Chretien Marie Francoise; Lebouvier Brigitte; Denis Alain; Chappard Daniel 《Human reproduction (Oxford, England)》1998,13(10):2767-2771
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments. 相似文献
158.
The present study was designed to examine the effects of a >30kDa fraction of medium conditioned for 2 days by adult rat seminiferoustubules on inhibin secretion by cultured tubules, and on spermatogenesisand fertility of male rats. Inhibin secretion was assayed byadding the >30 kDa fraction to 5 cm segments of adult ratseminiferous tubules and measuring inhibin by radioimmunoassayat 2 day intervals. Fertility was assayed by injecting malerats daily for up to 45 days with the >30 kDa fraction andthen mating them with a proestrus female, or by injecting for15 days and mating them with two female rats. The assay usedto evaluate the in-vivo effect of the >30 kDa fraction onthe testis involved an assessment of frequencies of seminiferoustubule stages scored by transillumination on intact tubules.The addition of the >30 kDa fraction to the adult rat seminiferoustubules cultured for 2 days resulted in an inhibition of inhibinsecretion into the medium. This effect was reversed when thefraction was removed and changed with fresh medium and culturedfor a further 4 days. The >30 kDa fraction administered i.p.to adult male rats resulted in a low fertilization rate comparedto control rats (67%) (P < 0.05). The assessment of frequenciesof seminiferous tubule stages scored by transillumination showedan increased frequency of stage VI and decreased frequency ofstages VII and VIII after treatment. The results of the presentstudy provide additional evidence that local regulation of Sertolicell function is mediated by a >30 kDa component or componentssecreted by adult seminiferous tubules which could arrest spermatogenesis. 相似文献
159.
泵式自体输血过滤引流系统在急症救护中的应用 总被引:5,自引:1,他引:4
自体输血、胸腔闭式引流,是缓解血源矛盾、赢得抢救时机、防治心肺衰竭及ARDS/MOF的重要措施。笔者研制成功的手控泵式储血过滤引流系列在战地、灾害现场,以及平时的心肺手术中,共应用3000余例,现重点对其功能设计和用于自体输血、紧急救护做讨论和评估。 相似文献
160.
C. Caramella F. Ferrari M. C. Bonferoni M. E. Sangalli M. De Bernardi Di Valserra F. Feletti M. R. Galmozzi 《Biopharmaceutics & drug disposition》1993,14(2):143-160
Six preparations were considered: three multiple unit dosage forms (micropellets in capsules) (D, E and G) and one matrix tablet (B) were experimental prolonged release formulations, two non-disintegrating tablets (A and C) were commercial products. The in vitro dissolution behaviour of the differing formulations was investigated using the USP XXII paddle apparatus. The in vivo study was effected on a panel of 12 healthy volunteers. The two commercial tablets (A and C) showed mean dissolution time (MDT) of 1.34 and 1.44 h and td of 91 and 92 min, respectively; for prolonged release formulations (B, E, D, and G) MDT ranged between 2.28 and 4.23 h and td between 149 and 291 min. The mean residence time (MRT) was 8.68 and 6.47 h for tablets A and C, respectively; it ranged between 9.62 and 10.24 h for the multiple unit formulations E, D, and G and was 11.27 h for matrix B. Formulation B also showed the higher apparent elimination half-life t1/2 (7.12 h), while apparent t1/2 for all the other formulations were very similar, ranging between 5.04 and 5.28 h. High variability between the various formulations was found for Cmax and AUC values, and no relationships could be established with the type of formulation. An in vitro/in vivo correlation was found for all the formulations examined on the basis of analogous parameters (MDT and MRT); (r = 0.83, p <0.05). In a few cases the Wagner-Nelson deconvolution method was applied to individual plasma level versus time curves and the corresponding absorption curves were obtained. In these cases the in vitro/in vivo correlation was tested on the basis of the comparison of the in vivo absorption curves with the in vitro dissolution profiles. This was accomplished using the ‘Levy's plot’ (per cent released versus per cent absorbed) approach and provided further support for the correlation found. 相似文献