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11.
Summary Influences of the wake-sleep states on spontaneous activity of thalamic ventro-basal neurons have been studied in the chronic cat using the following analyses for cell discharges: mean firing rate, interspike histogram and joint interval histogram (J.I.H.). While slow wave sleep is accompagnied by a characteristic firing pattern it is more difficult to compare spontaneous unit activity during wakefulness (W) and desynchronised sleep (D).A detailed analysis (especially of the J.I.H.) of the same neuron during the three states indicates marked differences between W and D; on the contrary, the intraburst pattern shows definite similarities between D and S. The greatest stability in the firing pattern of a given neuron is found during S on long recording. During D the variability in the firing pattern is mainly due to phasic activity but may also be related to tonic changes.  相似文献   
12.
Neuromedin B (NMB) is a mammalian bombesin (BN)-like peptide that exerts its function via the neuromedin B receptor (NMB-R). The NMB/NMB-R system is involved in stress response, and therefore we examined behavioral properties in female mice lacking NMB-R using a restraint-induced stress paradigm. Thirty minutes of restraint in a wire mesh cage constituted a sufficient stress stimulus for mice as evidenced by elevated blood glucose concentrations in stressed wild-type and NMB-R-deficient mice. Using a one-trial passive avoidance test, stressed NMB-R-deficient mice exhibited a marked reduction in memory performance. NMB-R-deficient mice exhibited elevated spontaneous activity in a novel environment compared to non-stressed mutant mice after 30-min stress, and a similar difference was also observed between stressed/non-stressed wild-type mice. An elevated plus maze test showed that the stress stimulus had no effect on anxiety in either wild-type or NMB-R-deficient mice. Furthermore, pain response of wild-type and NMB-R-deficient mice induced by electric foot shock was not affected under either stressed or non-stressed conditions. These results indicate that impaired memory performance in stressed NMB-R-deficient mice is not a consequence of changes in spontaneous activity, anxiety, or pain response, and suggest that the NMB/NMB-R pathway may play a role in regulating the stress response via the neural system that controls learning and memory.  相似文献   
13.
Abstract Spontaneous lymphvascular reanastomosis (SLR) following small bowel transplantation in rats is of clinical relevance for the resorption of long chain fatty acids. Detailed morphological and molecular data concerning the process of lymphvascular reanastomosis are not available in the literature. In this study SLR was investigated using microradiology and scanning electron microscopy. Between the 8th and 21st postoperative days following transplantation SLR does not occur between the intestinal trunk of the transplant and the thoracic duct of the recipient. Instead, an indirect connection was observed between the inserted advential lymphatic vessels of the mesenteric artery and lymphatic vessels of the aorta or ductus deferens, which are connected with the thoracic duct.  相似文献   
14.
Spontaneous recurrent abortion (SRA) has been treated by means of immunization with paternal or third-party white blood cells, yet the immunological basis for SRA and for the role of immunization protocols in pregnancy outcome remains controversial. To elucidate this question, nine women with SRA were immunized with paternal mononuclear cells and studied before and 2 weeks after immunization. Seven women who became pregnant gave birth to live newborns. Secretion of the T helper 1 cytokines IL-2 and interferon- by patients' mononuclear cells decreased, while production of IL-10 increased. The levels of natural killer and lymphokine-activated killer cell-mediated cytotoxicity were markedly decreased. Monocyte functions such as secretion of IL-l, tumor necrosis factor a, IL-6, and cytotoxic activity decreased concurrently with elevations in IL-10 and transforming growth factor secretion. Production of IL-12, a pivotal regulatory cytokine, decreased. Furthermore, B7/1 expression on patients' mononuclear cells was downregulated. This resulted in a decrease in monocyte costimulatory activity of purified T cells with soluble anti-CD3, paralleled by a decline in allogeneic proliferative responses. These results suggest that the improved pregnancy success rate in women with SRA following immunization may be partly related to suppression of cell-mediated immunity and monocyte and natural killer cell activity.  相似文献   
15.
王林  李玉明  李皆 《河北医学》2001,7(8):675-678
目的:研究左旋精氨酸、牛磺酸、卡托普利单用及合用对自发性高血压大鼠的血压以及血神经肽Y、血脂水平的影响。方法:①用MRB-ⅢA型血压记录仪(上海第二医科大学高血压研究所),在大鼠清醒状态下,测鼠尾的尾动脉收缩压。②用酶法测定血清胆固醇(TC)、甘油三酯(TG)。③用^125I标记法和放射免疫法测血浆神经肽Y。结果:①经过四周药物治疗,左旋精氨酸且(L-arg)、牛磺酸组(Tau)血压均无变化(P>0.05)。卡托普利组(Cap )、三药合用组(L-arg Tau Cap)血压均下降(P<0.0005),L-arg Tau Cap组,血压下降比卡托普利组明显(P<0.01)。②经过四周药物治疗,牛磺酸组TC降低,TG无变化。L-arg Tau Cap组TC和TG均降低,左旋精氨酸组、卡托普利组TC和TG均无变化(P>0.05)。③经过四周药物治疗,左旋精氨酸组、牛磺酸组NPY无变化(P>0.05)。卡托普利组、L-arg Tau Cap 组NPY下降。用药前后,四组SHR大鼠血压高低与血浆神经肽Y的浓度均呈正相关(P<0.05)。结论:①四组大鼠治疗后,左旋精氨酸、牛磺酸组血压换变化;卡托普利组和合用组均出现血压降低,合用组降压效果经弹卡托普利明显。②牛磺酸治疗组血清胆固醇降低;三种药物合用组血清胆固醇和甘油三酯的降低。左旋精氨酸组、卡托普利组血脂无变化。③自发 性高血压大鼠的血压变化与血浆神经肽Y浓度的变化呈正相关,神经肽Y可能参与了高血压的发生发展。  相似文献   
16.
Summary The spontaneous activity of primary vestibular neurons was studied during postnatal development in the cat. Activities were categorized as regular, intermediate and irregular on the basis of the coefficient of variation. At birth, few regularly firing units were found while the percentage of intermediate and irregular units was high. During development, the percentage of units meeting the criterion of regularity increased steadily with age. At the same time the number of intermediate and irregular units decreased. The average resting rate of all categories of unit showed an increase in firing from birth up to the adult stage, i. e., around the second postnatal month. The mean firing rate of regularly firing units was always higher than the two other categories throughout all the stages of development. These results were compared with similar work performed in the rat.Supported by grants from the C.N.R.S. (E.R.A.-187) and D.G.R.S.T. (no. 79-7-1073)  相似文献   
17.
18.
对32例顽固性复发性气胸患者用60%泛影葡胺进行胸膜腔造影,确定裂口后作硬化剂治疗,并作复张后胸部CT对照及手术追踪对照,取得满意效果。  相似文献   
19.
We prospectively studied thoracoscopic suturing of apical bullae in the management of primary spontaneous pneumothorax. From June 1993 to July 1994, we performed 29 such procedures in 27 patients. (All males ranging in age from 15 to 40.) Bullae less than 2 cm in diameter were imbricated (18), while larger bullae were resected and repaired with 3/0 polypropylene suture (11). Postoperative morbidity was minimal. Averaged postoperative parenteral narcotic (Pethidine) requirement was 88 mg, chest drainage was 1.7 (range 1–4) days, and hospital stay was 2.5 (range 1–7) days. There was no recurrence after a mean follow-up of 10 months. In comparison, 32 patients prior to this study period underwent staple resection of apical bulla. Demographic data in the two groups were similar. Averaged Pethidine requirement in the staple group was 98 mg, chest drainage was 1.8 (range 1–5) days, and hospital stay was 2.6 (range 1–7) days. There was no statistical difference in the two groups with respect to pain medication, chest drainage, or hospital stay. The technique of thoracoscopic suturing can be easily acquired. In view of the high cost of staple-cutters, endoscopic suturing should be considered as a viable alternative to staple resection of apical bullae in the treatment of primary spontaneous pneumothorax.Presented in part at the 4th World Congress of Endoscopic Surgery, Kyoto, Japan, June 16–19, 1994 [6]  相似文献   
20.
Following systemic administration of the noradrenaline (NA) neurotoxin, DSP4 (50 mg/kg), rats were found to be retarded in the rate at which they acquired the "right-turn" running response in a modified T-maze choice situation, as measured by the total number of errors per session and median latency to reach the goal box. Desipramine (DMI, 20 mg/kg), injected 30 min before DSP4 blocked the acquisition retardation. DSP4 was found to have a short-lasting effect upon spontaneous motor activity, while food and water intake recovery was complete within 7 days of the injection. Both the NA-accumulation data and endogenous NA concentrations indicated profound NA, but not 5-hydroxytryptamine (5-HT) and dopamine (DA), depletions in the cortex, hippocampus and cerebellum. These data seem to confirm the role of the locus coeruleus-noradrenaline (LC-NA) system in an instrumental learning situation.  相似文献   
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