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41.
42.
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
43.
Yaping Deng huashang Zhou Junguo DuanDepartment of Ophthalmology the Teaching Hospital of Chengdu College of TCM Chengdu China 《眼科学报》1994,(1)
Twenty five cases, including 26 eyes with retinal vein occlusion (RVO) were examined by means of the electro-oculogram. The results showed that 23 of the 26 eyes suffering from RVO exhibited abnormalities of the electro-oculogram (EOG). The potential difference and Arden ratio in the RVO eyes were lower than those in the normal eyes (P<0.01). The more the visual acuity of ill eyes was decreased, the higher the abnormal rate of EOG in ill eyes was. 14 eyes had the visual acuity less than 0.1, whose EOGs were abnortmal. Six eyes had the visual acuity from 0. 2 to 0. 4, in which the EOGs of 5 eyes were abnormal. Six eyes had the visual acuity more than 0. 5, a-mong which the EOGs of 4 eyes were abnormal. Based on the above observations, it may be considered that the circulatory disturbance resulting from RVO damages not only the internal layer but also the external layer of the retina. We suggest that EOG is a useful method for distingquishing lesions caused by RVO and may reflect the functional condition 相似文献
44.
报告应闭合式玻璃体切除术治疗7例(7眼)因视网膜静脉阻塞所致的玻璃体出血。所有病人术后眼底清晰可见,视力明显提高。术后4例出现再出血,经药物治疗后出血吸收,加用氩离子激光视网膜光凝,无再出血。随访3至18个月所有病人无新生血管性青光眼及牵引性视网膜脱离出现。认为玻璃体切除术不但能使屈光间质恢复透明,视力提高,预防牵引性视网膜脱离,而且为明确诊断和进一步激光治疗提供条件。 相似文献
45.
Maryla Z Stelmach MB BS Justin O'Day FRACO FRACS † Hugh Ryan FRACO FRACS ‡ 《Clinical & experimental ophthalmology》1994,22(2):139-143
The history and clinical findings are presented of a patient who suffered from the uveal effusion syndrome over a 10-year period from 1956. The funduscopic appearance is illustrated both at the time of initial presentation and 36 years later. This condition typically affects healthy middle-aged men and causes recurrent, spontaneous, serous retinal and ciliochoroidal detachments, often resulting in significant visual impairment. Two separate hypotheses have been postulated to explain the pathogenesis of the uveal effusion syndrome, one relating to abnormally thickened sclera, the other to chronic bulbar hypotony. Both are discussed, as is the rationale behind the current management of this unusual condition. 相似文献
46.
Hiroshi Ujike Kazuo Tsuchida Kazufumi Akiyama Yutaka Fujiwara Shigetoshi Kuroda 《Pharmacology, biochemistry, and behavior》1995,50(4):613-617
The ontogeny of the behavioral effects of acute cocaine administration and behavioral sensitization to cocaine in rat pups was investigated. Acute behavior stimulating effects of cocaine were observed in pups as young as 7 postnatal days (PND) old, although they needed a higher dose of cocaine than adult rats to evoke the same motor effects. An adult dose-response curve pattern of stereotypy and locomotion to acute cocaine treatment was observed at PND 21, and of rearing at PND 28. Rats aged PND 7, 14, 21, 28, and 56 received repeated injections of saline or cocaine (15 mg/kg) twice a day for 5 consecutive days. After a 3-week period of abstinence, sensitization to a challenge dose of cocaine was assessed. Cocaine-induced stereotyped behavior was enhanced significantly only in rats in which cocaine pretreatment was initiated on PND 21, 28, and 56, but not earlier on PND 7 and 14. Adult female rats given repeated cocaine injections on PND 56–60 showed significantly greater sensitization than males, but no such sex difference was observed in pups given cocaine repeatedly on PND 21–25 or 28–32. These results show clearly that cocaine-induced behavioral sensitization in rats occurred only when subchronic cocaine administration was commenced on PND 21 or later. 相似文献
47.
L Peichl 《The Journal of comparative neurology》1992,324(4):590-602
The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium-sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores. Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160-200 microns to about 1,100 microns diameter, and beta cell fields from 25 microns to about 360 microns diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk-transient (Y), and dog beta cells brisk-sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the cat. 相似文献
48.
用辣根过氧化物酶标记的AcLDL2培养小白鼠腹腔巨噬细胞,直观地显示了巨噬细胞表面AcLDL受体的存在,此受体只特异性的识别修饰的LDL,其识别作用与配体分子荷大量负电荷有关。 相似文献
49.
F. R. Robert H. Martens N. Cormann A. Benhida J. Schoenen V. Geenen 《Clinical & developmental immunology》1992,2(2):131-140
Neuropeptide signals and specific neuropeptide receptors have been described in the
thymus supporting the concept of a close dialogue between the neuroendocrine and the
immune systems at the level of early T-cell differentiation. In this paper, we review
recent data about neurohypophysial (NHP)-related peptides detected in the thymus
from different species. We suggest that we are dealing in fact with other member(s) of
the NHP hormone family, which seems to exert its activity locally through a novel
model of cell-to-cell signaling, that of cryptocrine communication. This model involves
exchange of signals between thymic epithelial cells and developing thymocytes. The
NHP-related peptides have been shown to trigger thymocyte proliferation and could
induce immune tolerance of this highly conserved neuroendocrine family. 相似文献
50.
C. W. Pagenkopf J-P. Bourreau C. E. Challice 《Clinical and experimental pharmacology & physiology》1990,17(8):557-565
1. Age-related changes in prejunctional alpha 2-adrenoceptors were examined in the rat vas deferens using pharmacological techniques. 2. B-HT 933 (1 x 10(-8) - 1 x 10(-6) mol/L) caused a concentration-dependent inhibition of isometric contractions (tetrodotoxin-sensitive) induced by stimulation with single field-stimulus pulses, in both the epididymal and prostatic regions of rat vas deferens. The concentration-response curve to B-HT 933 was shifted to the right with age in the prostatic regions of the vas deferens. 3. In high concentrations (10(-6) - 3 x 10(-4) mol/L), B-HT 933 caused concentration-dependent enhancement of the contractile response to stimulation and evoked spontaneous contractile activity. No significant difference in this postjunctional activity occurred with age in either the prostatic or epididymal regions of the vas deferens. 4. Schild analysis revealed no significant differences in pA2 values for the antagonisms of the prejunctional inhibitory effect of B-HT 933 by rauwolscine in either the prostatic or epididymal regions of vas deferens between young and old rats. 5. These results could be interpreted as a decrease in alpha 2-adrenoceptor number with age. The more marked decrease in the prejunctional inhibitor potency of B-HT 933 in prostatic regions of vas deferens with aging may be due to a smaller receptor reserve in this region of the vas deferens. 相似文献