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11.
To investigate whether the phosphorylation of extracellular signal-regulated kinase (ERK) is involved in autoimmune injury of the peripheral nervous system (PNS), the expression of phosphorylated ERK (p-ERK) was analyzed in experimental autoimmune neuritis (EAN) in rats. Western blot analysis showed that the level of p-ERK was increased significantly in the sciatic nerves of rats on days 14 (p<0.05) and 24 (p<0.01) post-immunization, compared with controls, and its reaction declined at day 30 post-immunization. Immunohistochemistry showed that p-ERK protein was weakly expressed in Schwann cells and vascular endothelial cells in the sciatic nerves of CFA-immunized control rats. In EAN-affected sciatic nerves, p-ERK immunoreactivity was found mainly in ED1-positive macrophages on days 14 and 24 post-immunization. Moreover, on days 24 and 30 post-immunization, p-ERK immunoreactivity increased gradually in the Schwann cells of rat sciatic nerves with EAN. Based on these results, we postulated that the phosphorylation of ERK has an important role in the differentiation and survival of cells, including inflammatory cells and Schwann cells, in the rat sciatic nerve in EAN. Specifically, the activation of ERK in the recovery phase of EAN paralysis seems to be related in the survival of Schwann cells.  相似文献   
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Intrapontine microinjections of serotonin in acutely decerebrated cats resulted in the bilateral augmentation of the postural muscle tone of the hindlimbs. Optimal injection sites were located in the dorsomedial part of the rostral pontine reticular formation corresponding to the nucleus reticularis ponds oralis (NRPo). In this study, attempts were made to elucidate the cellular basis for the serotoninergically induced augmentation of postural muscle tone by recording the electromyographic (EMG) activity of hindlimb extensor muscles, the monosynaptic reflex responses evoked by electrical stimulation of group Ia muscle afferent fibres and the membrane potentials of hindlimb alpha-motoneurons (MNs). Serotonin injections resulted not only in the augmentation of the EMG activity of gastrocnemius soleus muscles, but also in the restoration of EMG suppression, which was induced by previous injection of carbachol into the NRPo. Extensor and flexor monosynaptic reflex responses were facilitated by serotonin injections into the NRPo. Such reflex facilitation was not induced by serotonin injections into the mesencephalic or the medullary reticular formation. Intrapontine serotonin injections resulted in membrane depolarization of extensor and flexor MNs with decreases in input resistance and rheobase. Spontaneous depolarizing synaptic potentials (EPSPs) increased in both frequency and amplitude. Peak voltage of Ia monosynaptic EPSPs also increased. Serotonin injections which followed carbachol injections resulted in membrane depolarization of MNs along with an increase in the frequency of spontaneous EPSPs and a decrease in carbachol-induced inhibitory postsynaptic potentials. Following pontine carbachol injections, antidromic and orthodromic responses in MNs were suppressed. Discharges of MNs evoked by intracellular current injections were also suppressed, but were restored following serotonin injections. These results indicate that postsynaptic excitation, presynaptic facilitation and disinhibition (withdrawal of postsynaptic inhibition) simultaneously act on the hindlimb MNs during serotonin-induced postural augmentation and restoration.  相似文献   
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ObjectiveThis study aimed to compare longitudinal changes in ovarian reserve markers after cesarean section (CS) with and without bilateral salpingectomy (BS).Study designWe prospectively enrolled women >35 weeks’ gestation scheduled for CS alone or CS + BS and obtained blood samples for anti-Müllerian hormone prior to surgery and at 3 and 6 months after surgery. At the 3-month visit, we similarly performed transvaginal ultrasound for antral follicle count.ResultsWe enrolled 50 women; 30 underwent CS only and 20 underwent CS + BS. Although anti-Müllerian hormone level increased over 6 months of follow-up in both groups, no clinically important differences in the geometric mean (interquartile range) (ng/mL) were observed at any timepoint (baseline [0.69 {0.36?1.21} {CS only} vs 0.49 {0.32?2.10} {CS + BS}, p = 0.64]; 3 months [1.35 {0.58?3.13} vs 1.45 {1.04?2.25}, p = 0.79]; and 6 months [1.74 {0.93?4.45} vs 2.60 {1.41?5.10}, p =0.27]). Similarly, we detected no difference in antral follicle count.ConclusionBS at the time of CS does not have a negative impact on ovarian reserve 6 months after surgery.ImplicationWhile our results provide reassuring data that bilateral salpingectomy for permanent contraception at the time of cesarean section does not impact ovarian reserve, longer adequately powered studies are needed.  相似文献   
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Paradoxical inward rib cage movement in children is quantified by the labored breathing index (LBI) on the respiratory inductive plethysmography. Labored breathing index during rapid eye movement sleep (REMS) in 59 children without obvious sleep disordered breathing (SDB) declined with age, and decreased to the mature low level at 35 months of age. The LBI was also found to reflect well the severity of SDB. Paradoxical inward rib cage movement, which was quantified by LBI, is concluded to be an important finding in diagnosing SDB in child patients.  相似文献   
16.
Abstract We report here a case of neonatal hyperthyroidism born to a mother, whose pregnancy was complicated by poorly controlled Graves' disease. The patient demonstrated exophthalmos and marked goiter at birth, indicating the existence of thyrotoxicosis in utero. The mother's Graves' disease was well controlled in the third trimester, resulting in a slightly lower level of free thyroxine (FT4) in the umbilical cord blood serum; however, thyroid-stimulating hormone (TSH) was undetectable. Thyroid-stimulating hormone remained undetectable for 2 months, while FT4 levels varied in the course. This case suggests that severe and prolonged thyrotoxicosis in utero, due to poor control of pregnancy with Graves' disease, might induce unresponsiveness of the hypothalamo-pituitary system in the newborn.  相似文献   
17.
We calculated the standardized mortality ratios (SMRs) of biliary tract cancer (BTC) in Japan from 1981 to 1990 and statistically analyzed the results according to 333 Secondary Areas of Medical Care, as well as sex and subsite [gallbladder cancer (GBC) and extrahepatic bile duct cancer (BDC)], in order to examine geographic clustering patterns of BTC. In GBC in both sexes, the Secondary Areas of Medical Care with high SMRs were clustered in the eastern part of Japan. In BDC in both sexes, the Areas with high SMRs were clustered between the northern and eastern parts of Japan. In comparison with GBC, this clustering favored the northern part of Japan. In males, the clustering pattern in mortality from BTC was mainly due to the occurrence of BDC. In females, the clustering pattern in mortality from BTC reflected that of GBC. The clustering of BTC, especially GBC, seems to be related to the distribution of plains, basins, and rivers.  相似文献   
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Objectives: To compare three positions for defecation by measuring abdominal pressure and the anorectal angle simultaneously. Methods: We recruited six healthy volunteers. The videomanometric measures included simultaneous fluoroscopic images, abdominal pressures, subtracted rectal pressures and anal sphincter pressures. Three positions were used: sitting, sitting with the hip flexing at 60 ° with respect to the rest of the body, and squatting with the hip flexing at 22.5 ° with respect to the rest of the body. Results: Basal abdominal pressure before defecation on hip‐flex sitting was lower than that with normal sitting, although the difference did not reach statistical significance. Basal abdominal pressure before defecation on squatting (26 cmH2O) was lower than that with normal sitting (P < 0.01). Abdominal pressure increase (strain) on hip‐flex sitting was lower than that with normal sitting, although this difference did not reach statistical significance. Similarly, the abdominal pressure increase on squatting was smaller than that with normal sitting, and yet the difference did not reach statistical significance. The rectoanal angle on defecation on hip‐flex sitting did not differ from that with normal sitting. The rectoanal angle on defecation on squatting (126 °) was larger than that with normal sitting (100 °) (P < 0.05), and was also larger than that with hip‐flex sitting (99 °) (P < 0.01). Conclusion: The results of the present study suggest that the greater the hip flexion achieved by squatting, the straighter the rectoanal canal will be, and accordingly, less strain will be required for defecation.  相似文献   
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