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21.
Sympathetic skin response (SSR) and R–R interval variation (RRIV) were studied in 36 chronic, nondiabetic uremics to compare with their nerve conduction studies (NCS) and clinical dysautonomia. Abnormal SSR was noted in 5 (13.9%) patients, abnormal RRIV in 14 (38.9%), and abnormal NCS in 26 (72.2%). The patients were classified into three groups: group (GP) 1: “normal,” n = 21 (58.3%), normal RRIV and SSR; GP 2: “isolated parasympathetic dysfunction,” n = 10 (27.8%), abnormal RRIV and normal SSR; and GP 3: “sympathetic sudomotor dysfunction,” n = 5 (13.9%), abnormal SSR. A significant difference in age was found among the three groups (GP 3 > GP 2 > GP 1; P < 0.0001, ANOVA). After controlling the age factor, we still noted a tendency toward increasing NCS disturbances (distal latency and nerve conduction velocity of peroneal nerve; P < 0.05, multiple regression analysis) and frequencies of clinical autonomic symptoms (postural dizziness and impotence; P < 0.05, Mantel–Hanszel test) from GP 1 to GP 3. Patients with abnormal SSR (GP 3) displayed significantly higher frequencies of postural dizziness and impotence, indicating the relationship between an absence of SSR and clinical dysautonomia. © 1994 John Wiley & Sons, Inc.  相似文献   
22.
Abstract: The Self-Rating Body Image (SRBI) test was used to determine whether the patients with eating disorders such as anorexia nervosa or bulimia showed their body image disturbance or not. The SRBI was completed by 120 subjects who consisted of 30 low weight (LW) controls, 30 normal weight (NW) controls, 30 high weight (HW) controls, 18 anorexic patients (AN) and 12 bulimic patients (BN). The AN group had a significantly greater dissatisfaction with the scales of the body shape, visceral organ and face image of the SRBI than the weight-matched LW group. The BN group had a significantly greater dissatisfaction with the visceral organ image than the weight-matched NW group. However, no significant difference in the body shape and face images between the BN and NW groups was found. Our results suggest that the anorexic patients may disturb more parts of the body image than the bulimic patients though both the anorexic and bulimic patients showed the disturbance of body image.  相似文献   
23.
Peripheral and central injections of recombinant human interleukin-1β (IL-1β) have been shown to decrease social exploration and to induce body weight loss in rats. To characterize the receptor mechanisms of these effects, we used as a tool a specific antagonist of the receptors of IL-1, IL-1ra. Intraperitoneal (i.p.) administration of IL-1ra (8 mg/kg) blocked the effect of i.p. injection of IL-1β (4 μg/rat) on social behaviour but not on body weight. Central administration of IL-1ra (60 μg/rat, i.c.v.) abrogated the effects of centrally administered IL-1β (30 ngn/rat, i.c.v.) on both social behaviour and body weight. Central injection of IL-1ra (4 μg/rat, i.c.v.) also attenuated the effects of i.p. administered IL-1β (4 μg/rat) on social behaviour but not on body weight. These results suggest that the effects of IL-1β on social behavior are mediated centrally and that its effect on the loss of body weight involves different receptor mechanisms.  相似文献   
24.
25.
The microstructure of the calls and songs of four generations of Roller canaries was analyzed and compared. Many of the characteristics of the internal structure of the syllable show distributions in the progeny that suggest quantitative inheritance. The presence or absence of an underharmonic and the presence of a block underharmonic show a qualitative type of inheritance.  相似文献   
26.
Summary An analysis of autopsy data shows that during the period 1928–1972 the relative frequency of carcinoma of the stomach has remained practically unchanged. A similar trend is apparant from the mortality statistics for Vienna from 1955 to 1972. Whereas for the lower and middle age groups there is a real decrease during the period 1928–1952, an opposite trend is visible for the highest age group. The stomach and the lower parts of the large intestine are the most frequent sites of carcinoma of the alimentary canal. The frequency distribution is explained on the basis of the contact hypothesis.  相似文献   
27.
Summary: Bis(phenoxy‐imine) Zr complexes with MAO activation can produce polyethylenes with well‐defined bimodal molecular weight distributions. Polymerization behavior indicates that minor changes in the ligand structures can have a significant effect on the modality of the resulting polyethylenes. Although there is no direct relationship between the bimodal catalytic behavior and the structure of a precatalyst complex in solution, a precatalyst complex having a methyl or methoxy group para to the phenoxy‐oxygen inclined to exhibit bimodal behavior whereas that with a pentafluorophenyl group on the imine‐nitrogen displayed unimodal behavior. Polymerization results suggest that bimodal behavior is linked to the presence of two kinds of cationic active species, which arise from different modes of ligand coordination. A qualitative correlation was found between the calculated amounts of possible cationic active species and the uni‐ and bimodal catalytic behavior. Based on the results obtained, we concluded that the bimodal polyethylenes are produced by two kinds of cationic active species having two available cis‐located sites with cis‐N, trans‐O and cis‐N, cis‐O arrangements. The results introduced herein are rare examples of the production of well‐defined bimodal polyethylenes using a single precatalyst.

Bis(phenoxy imine) Zr complexes can produce well‐defined bimodal polyethylenes.  相似文献   

28.
目的:观察白松片对慢性应激抑郁大鼠模型行为学和血浆CORT、ACTH含量的影响。方法:SD雄性大鼠28只随机分为空白对照组、模型对照组、氟西汀对照组及白松片试验组,选用慢性轻度不可预见性应激加孤养造模,观察各组大鼠敞箱实验和液体消耗等行为学指标变化,采用放射免疫方法检测大鼠血浆皮质醇(CORT)和促肾上腺皮质激素(ACTH)含量。结果:慢性应激抑郁大鼠体重增加缓慢,敞箱实验中的水平运动、垂直运动得分、清洁动作次数显著减少,中央格停留时间显著延长;糖水消耗明显下降,纯水消耗显著增多,而且其血浆皮质醇和促肾上腺皮质激素含量增加。氟西汀和白松片均显著改善慢性应激抑郁大鼠模型的行为学和神经内分泌变化。结论:慢性轻度不可预见性应激可使大鼠行为及神经内分泌发生异常改变,引起抑郁状态,白松片对此具有一定拮抗作用。  相似文献   
29.
The Oka vaccine strains of varicella-zoster virus (VZV) have a significantly different BgII DNA restriction pattern from that of American wild-type isolates of VZV. This difference consists primarily of an additional BgII site, which lies within the BamHI "D" fragment. In conjunction with a study of the efficacy of an experimental Merck/Oka VZV vaccine, the area of the genome from which the most marked restriction pattern alteration arises was studied more closely to determine if there are other significant differences between the Oka strains and American wild-type strains. BamHI "D" fragments from the DNA of the Oka parent strain (the progenitor of the vaccine strain), the RIT/Oka vaccine strain (a derivative of the Oka parent strain), the Merck/Oka vaccine strain, and the EF strain (an American wild type), were submitted to extensive endonuclease digestion studies to ascertain if additional unique restriction sites are present in the Oka parent or vaccine strains. The extra BgII restriction site characteristic of the Merck/Oka vaccine strain is also present in the DNA of the parent virus as well as its derivatives and was therefore not produced by the "attenuation" process. No other novel sites were found in the Oka parent or Oka-derived strains in this section of the genome. The Merck/Oka vaccine strain of VZV, despite its Japanese origin, is therefore quite similar to circulating American varicella-zoster virus strains. Varicella-zoster virus DNA, at least in the area of the BamHI D fragment, also appears to be remarkably stable from strain to strain.  相似文献   
30.
Studies on human T-cell lymphotropic virus types I (HTLV-I) and II (HTLV-II) are briefly reviewed from the viewpoint of molecular evolution, with special reference to the evolutionary rate and evolutionary relationships among these viruses. In particular, it appears that, in contrast to the low level of variability of HTLV-I among different isolates, individual isolates form quasispecies structures. Elucidating the mechanisms connecting these two phenomena will be one of the future problems in the study of the molecular evolution of HTLV-I and HTLV-II.  相似文献   
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