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31.
Tomoyuki Kawada M.D. Yasuo Kiryu M.D. Shigenobu Aoki Ph.D. Shosuke Suzuki M.D. 《Psychiatry and clinical neurosciences》1992,46(4):937-940
Abstract: The possibility on placing electrodes at Fpz-A2 instead of C3 -A2 was investigated to obtain a more stable configuration avoiding obstruction by the hair. Our original system of alpha wave detection by a microcomputer was used, and a total of 22 all-night hypnograms of five healthy young students waa recorded. Pearson's moment correlation coefficients of alpha wave % between the two positions were 0.780–0.948. Except for one subject, alpha wave % taken at Fpz-A2 tended to be 3–5% lower than that at C3 -A2 . The above analysis indicates that using EEG electrode position of Fpz-A2 is valid and useful as a stable electrode configuration for a long-time monitoring. 相似文献
32.
Binding of sulfaethidole to bovine serum albumin was studied by equilibrium dialysis, fluorescence probe technique, uv difference
spectrophotometry and circular dichroism. Equilibrium dialysis method enabled us to estimate the total number of drug binding
sites of albumin molecule. For sulfaethidole, albumin had 6 primary and 40 secondary binding sites. The primary and secondary
binding constants were 0.9×105 M−1 and 0.2×106 M−1, respectively. 1-Anilino-8-naphthalenesulfonate (ANS) and 2-(4′-hydroxylbenzeneazo)-benzoic acid (HBAB) were used as the
fluorescence probe and the uv spectrophotometric probe, respectively. In fluorescence probe technique, results indicated that
the number of higher affinity drug binding site of albumin was 1 and the number of lower affinity drug binding sites of albumin
was 3, and the primary and secondary drug binding constants for bovine serum albumin were 2.15×105 M−1 and 1.04×105 M−1, respectively. In uv difference spectrophotometry, binding sites were 3 and binding constant was 1.88×105 M−1. The above results suggest that several different methods should be used in ompensation for insufficient information about
drug binding to albumin molecule given by only one method. 相似文献
33.
Akihiro Ito Tadateru Takahashi Hiromitsu Watanabe Peter Osa Ogundigie Taro Okamoto 《Cancer science》1992,83(10):1052-1056
Mouse liver tumors occurring in C3H/HeN, C57BL/6N and C3B6F1 hybrid (C3H × C57BL) were studied following 252 Cf fission neutron irradiation. Three strains of mice of both sexes (about 30 mice/group) were irradiated once with 252 Cf at doses of 0,12.5, 50 and 200 cGy. The groups were observed for 13 months after irradiation. The incidence of liver tumors in the non-irradiated controls was 0% in both sexes of CS7BL/6N, 11.7% in males and 0% in females of C3B6F1 and 39.5% in males and 11.4% in females of C3H/HeN mice. In the four strains of mice thus far studied, including B6C3F1 hybrid (CS7BL × C3H) which was previously studied, 252 Cf irradiation has increased the tumor incidence dose-dependently in males and in females, but less effectively in females. The mean number and size of liver tumors were clearly correlated with tumor incidence. The incidence was always highest in C3H/HeN mice of both sexes, followed by B6C3F1, C3B6F1 and C57BL/6N mice. The influence of sex hormones was studied in B6C3F1 mice of both sexes after 200 cGy of 252 Cf irradiation. In males, the incidence of liver tumors was significantly decreased from 55.2% to 23.3% and 25.9% after orchidectomy, and in females it was slightly decreased from 27.6% to 14.8% and 18.8% after ovariectomy. Supplementation of testosterone in orchidectomized mice did not restore the occurrence of liver tumors. 相似文献
34.
应用体视学方法对卵巢浆液性肿瘤进行研究,从定量的角度对卵巢良性、交界性及恶性肿瘤的五项指标进行比较,包括(1)细胞核长短轴之比;(2)结缔组织间质与上皮细胞体积密度之比;(3)细胞核与细胞浆体积密度之比(核浆比);(4)细胞核平均直径;(5)乳头的上皮厚度。结果表明恶性肿瘤核浆体积密度比明显高于交界性及良性肿瘤(p<0.01);恶性肿瘤结缔组织间质与上皮细胞体积密度之比明显小于交界性及良性肿瘤(P<0.01)。 相似文献
35.
During the years 1959 to 1983 a doubling in the rate of homicide took place in Copenhagen. This increase was exclusively due to an increasing number of male offenders. By comparing with another Danish material, the frequency of female homicide as well as that of homicide combined with suicide was found practically unchanged since 1946, indicating that both of these kinds of homicides seem to have a background different from those of other offences of fatal violence. During the years 1959 to 1983, the criteria of selection of the defendants for a psychiatric examination for the court were fairly consistent. Examinations were performed in practically all cases, where a charge of murder raised by the police was followed by a legal trial for homicide. Less and less of the defendants, however, were hospitalized for the examination, while more were examined in The Clinic of Forensic Psychiatry in Copenhagen. 相似文献
36.
G. V. S. Murthy N. Janakiramaiah B. N. Gangadhar D. K. Subbakrishna 《Acta psychiatrica Scandinavica》1998,97(5):321-325
Consecutive male (n=100) and female (n= 100) DSM-IV schizophrenics newly registered for treatment in a large psychiatric hospital were examined with regard to age at onset of the first psychotic symptom. Age at onset of the first psychotic symptom did not differ between the sexes regardless of whether schizophrenia was diagnosed by DSM-IV or by several alternative systems. Age at onset defined by other criteria, namely age at first contact with a physician, and age at first admission for psychiatric care, also did not show any differences between the sexes. Survival analysis of subjects having a documented date of birth revealed a female preponderance at younger ages. A higher positive symptom score predicted older age at onset of the first psychotic symptom in the total sample. These findings call into question the universality of the traditional view of a younger age at onset of schizophrenia among males. Tentative neurodevelopmental and cultural explanations are presented to explain why there is no sex difference in age at onset of schizophrenia in India. 相似文献
37.
Sex differences in home range size and spatial ability are predictive of sex differences in the relative size of the hippocampus in rodents. Such differences in behavior and hippocampal volume are presumed to be, in part, the result of differences in perinatal exposure to hormones. We predicted from differences in the size of home ranges of male and female Mongolian gerbils (Meriones unguiculatus) in the wild that the hippocampus of male gerbils would be relatively larger than that of females. We examined the effect of prenatal hormonal influences on hippocampal size by comparing hippocampal volume of males and females from 2F and 2M intrauterine positions to that of randomly selected males and females. We found that, as predicted, randomly selected males had a significantly larger hippocampus, relative to telencephalon, than did randomly selected females. However, males and females from 2F and 2M intrauterine positions did not differ in relative hippocampal size. Possible explanations for the absence of a sex difference in hippocampal size in male and female gerbils from 2F and 2M intrauterine positions are discussed. 相似文献
38.
Ene I. Ette 《Computers in biology and medicine》1996,26(6):505-512
There is no method available to compare the fit of two non-hierarchical non-linear mixed effects models, although the common practice is to select the model with the lower objective function. Bootstrapping the log-likelihood differences (LLDs) of non-hierarchical models and constructing a bootstrap confidence interval on the LLDs is proposed for comparing the goodness-of-fit of such models. This is illustrated with different parameterizations of clearance models for an anti-infective agent in a longitudinal pharmacokinetic study which are compared. Additive and exponential models of creatinine clearance as a predictor of clearance are used as examples. 相似文献
39.
513例住院精神分裂症患者临床特点的性别差异 总被引:5,自引:0,他引:5
目的 :比较男性及女性精神分裂症住院病人的起病年龄、症状特点、病程演变特点及社会功能等指标的差异。方法 :选择 5 13例住院精神分裂症患者 ,详细收集临床资料 ,并进行《阳性及阴性症状评定量表》 (PANSS)及《大体功能量表》 (GAF)的评定 ,以此为依据进行性别间的比较分析。结果 :(1)总体上看 ,男性患者的起病年龄 (2 5 6± 7 3岁 )显著早于女性患者 (2 7 5± 8 6yrs) (P <0 0 1) ,但有家族史的患者间起病年龄差异不显著 (2 6 3± 6 9岁vs 2 6 8± 8 4岁 ) ;与男性相比 ,女性患者具有如下倾向 :症状模式较多为持续阳性症状 ,多为发作性波动或轻度恶化病程 ,阳性及情感症状更明显 ,且未婚或离婚的比例(5 3 9% )显著低于男性 (67 2 % )。结论 :男性及女性精神分裂症患者在发病年龄、症状特点及病程转归等多方面均存在显著差异 ,提示在制定治疗康复方案方面 ,应有所区别 相似文献
40.
Direct tubular effects of arginine vasopressin (AVP) on water and NaCl transport across the medullary thick ascending limb of Henle (MAL) were examined by the in vitro perfusion of isolated nephron fragments of mice, rats, and rabbits. Osmotic water permeability of the MAL of mice and rats was low and remained unchanged with 2 mU/ml AVP added to the bath. A dose-dependent increase in transepithelial electrical potential difference (PD) with AVP was observed in the mouse MAL when the ambient medium was isotonic. A similar result was also obtained when 2×10–4 mol/l dibutyryl adenosine 3,5-cyclic-monophosphate was added to the bath. In this preparation, AVP also caused an increase in the unidirectional Cl efflux from 323±45 to 398±61 pmoles·mm–1 ·min–1 (n=6,P<0.05). In contrast, under similar condition, we could not demonstrate any effect of AVP on PD, Cl efflux, or net Na flux in the rat MAL and on PD and Cl efflux in the rabbit MAL. Both PD and Cl efflux in the rat MAL were unaffected by AVP when the perfusate was made hypotonic. However, when the ambient medium was made hypertonic by adding NaCl and urea, a significant increase in PD was observed. In addition, we confirmed that AVP stimulated adenylate cyclase activity in the MAL as well as in the collecting tubule of mice and rats. We conclude that AVP stimulates Cl transport across the MAL of mice and rats by activating adenylate cyclase-cyclic AMP system. However, this effect of AVP may quantitatively vary among species. 相似文献