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41.
42.
A peculiar case of “nevus on nevus” was reported. A 67-year-old man had had a pigmented lesion in the left hypochondrial area since birth. The clinicopathologic findings of the pigmented lesion revealed a combination of speckled lentiginous nevus and patch-type blue nevus. This case of “nevus on nevus” is not described under the term of combined nevus as is current in the literature; it was considered to be a subtype of the type II atypical blue nevus described by Kawamura. 相似文献
43.
Select types of supporting cell in the inner ear express aquaporin-4 water channel protein 总被引:14,自引:0,他引:14
Yutaka Takumi Erlend Arnulf Nagelhus Jo Eidet Atsushi Matsubara Shin-ichi Usami Hideichi Shinkawa Søren Nielsen Ole Petter Ottersen 《The European journal of neuroscience》1998,10(12):3584-3595
Aquaporins (AQPs) confer a high water permeability on cell membranes and play important parts in secretory and absorptive epithelia in kidney and other organs. Here we investigate whether AQPs are expressed in the sensory epithelia of the inner ear, where a precise volume regulation is crucial. By use of specific antibodies it was found that the inner ear contains AQP1 and 4 while being devoid of detectable levels of AQP2, 3 or 5. Immunofluorescence and postembedding immunogold labelling revealed a strictly non-epithelial distribution of AQP1, confirming previous data. In contrast, AQP4 protein and mRNA (visualized by in situ hybridization) were concentrated in select types of supporting cell, including Hensen's cells and inner sulcus cells. Immunogold particles signalling AQP4 were confined to the basolateral plasma membrane of Hensen's cells and to the basal plasma membrane of Claudius cells and inner sulcus cells. AQP4 was also found in supporting cells of the vestibular end organs, but was absent from transitional epithelial cells and dark cells. Strong labelling for AQP4 and AQP4-mRNA was associated with the central part of the cochlear and vestibular nerves. Hair cells were consistently unlabelled. Our findings indicate that AQP4 may facilitate osmotically driven water fluxes in the sensory epithelia of the inner ear and thus contribute to the volume and ion homeostasis at these sites. 相似文献
44.
We report herein the cases of two infants who developed right pneumonectomy syndrome, both of whom were born with gross C-type esophageal atresia (EA/TEF), and a hypoplastic right lung arising from the lower esophagus, being a bronchopulmonary foregut malformation (BPFM). Appropriate and well-timed treatments for a variety of sequelae primarily caused by the mediastinal shift must be considered after right pneumonectomy in early childhood. 相似文献
45.
Katsuo Kamata Akemi Sakamoto Yutaka Kasuya 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(4):401-406
Summary The characteristics of the non-adrenergic, noncholinergic inhibitory response of the rat stomach fundus to transmural nerve stimulation were compared with the relaxation induced by vasoactive intestinal polypeptide (VIP). Treatment with -chymotrypsin (5 U/ml) or VIP antiserum (1:200) significantly reduced the relaxation induced by transmural nerve stimulation at 30 Hz, indicating that the possible transmitter in the non-adrenergic, non-cholinergic nerves is a peptide and may be VIP or a closely related peptide. VIP was able to relax, fully and dose-dependently, the stomach fundus that had previously been constricted by treatment with 10–6 M serotonin, and the IC50 value for VIP was 2.4 × 10–9 M. VIP elevated levels of cyclic AMP in a dose-dependent manner and the EC50 value was 2.8 × 10–9 M in the presence of 10–6 M atropine and 10–6 M guanethidine. The stomach fundus was relaxed by transmural nerve stimulation (30 Hz, 50 mA) and transmural nerve stimulation also caused production of cyclic AMP in the rat stomach in the presence of atropine and guanethidine. The basal level of cyclic AMP in the stomach was 8.7 ± 0.26 pmole/mg protein. When transmural nerve stimulation was applied for 5 min, the contraction of the stomach, induced by 10–6 M serotonin, was inhibited by 54% in the presence of atropine and guanethidine and the level of cyclic AMP was increased to 13.0 ± 0.73 pmol/mg protein. Apamin inhibited the transmural nerve stimulation-induced relaxation and shifted the dose-response curve for VIP to the right. These results suggest that one of the putative neurotransmitter from non-adrenergic, non-cholinergic nerves in the rat stomach is VIP and that VIP-induced relaxation may be mediated by the production of cyclic AMP and by the opening of apamin-sensitive K+-channels.Send offprint requests to K. Kamata at the above address 相似文献
46.
The FI (partially frozen injectate) system, a new closed-system devised by the authors for thermodilution cardiac output determinations, has two major features: 1) it needs no ice-filled receptacle to keep injectate cold because it uses partially frozen injectate, and 2) it can go without monitoring the injectate temperatures during the whole process of cardiac output determinations. The author evaluated the accuracy and reproducibility of cardiac output determinations with the FI system in 10 critically ill patients, as compared with another closed-system (which is commercially available) and the standard open method. The injectate temperatures in the FI system were also measured in vitro. The mean injectate temperature in the FI system was 0.71 ± 0.26°C and 80% of the injectate temperatures were lower than 1.0°C. Even when no monitoring of injectate temperatures was made, the predicated error in the calculated cardiac output resulted as low as 2% with the FI system. The mean cardiac output values were not statistically different between the FI system and the other two systems.(Maruta H, Usuda Y, Okutsu Y et al.: A new closed-system using partially frozen injectate for thermodilution cardiac output determinations. J Anesth 3: 35–39, 1989) 相似文献
47.
Suzuki Hisamitsu; Ota Kazuo; Ohno Ryuzo; Masaoka Toru; Shibata Hirotoshi; Kimura Ikuro; Amaki Ichita; Miura Yasusada; Uzuka Yoshiro; Kawato Masafumi; Shirakawa Shigeru; Hirota Yutaka; Maekawa Tadashi; lmai Kuniyuki; Takaku Fumimaro; Shimoyama Masanori; Kitahara Takeshi; Oguro Masao; Kozuru Mitsuo; Kawagoe Hiroya; Nakamura Toru; Yamada Kazumasa 《Japanese journal of clinical oncology》1989,19(4):338-347
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 19711975 to 62.3%during 19811985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 19711975and 69.7% during 19811985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 3740 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe. 相似文献
48.
Uchida Y Ohshima T Sasaki Y Suzuki H Yanai S Yamashita N Nakamura F Takei K Ihara Y Mikoshiba K Kolattukudy P Honnorat J Goshima Y 《Genes to cells : devoted to molecular & cellular mechanisms》2005,10(2):165-179
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins. 相似文献
49.
Endo Y Yamauchi K Tsutsui Y Ishihara Z Yamazaki F Sagawa S Shiraki K 《The Japanese journal of physiology》2002,52(5):421-427
To investigate the possible involvement of the sympathetic nervous system in pressor response during water drinking, muscle sympathetic nerve activity (MSNA), blood pressure (BP), and heart rate (HR) were continuously measured in healthy young volunteers throughout the experiments of a 5-min control, 2 min of drinking 500 ml water, and a 28-min recovery. To avoid the effects of water passing through the oropharyngeal and esophageal regions and/or effects of swallowing, an equal amount of water was directly infused to the stomach through a stomach tube for 2 min. Water drinking caused a transient increase in mean arterial pressure (MAP) and HR immediately after drinking (DeltaMAP, 12.6 +/- 2.1 mmHg; DeltaHR, +19.9 +/- 1.7 beats/min at the peak). An abrupt decrease of MSNA was observed directly during water drinking (Deltaburst rate, -6.9 +/- 1.3 bursts/min; Deltatotal activity, -2,606 +/- 491 U/min), and it increased to the baseline level thereafter. Gastric infusion had little or no effect on MAP, HR, and MSNA. The present study demonstrated that a pressor response during water drinking was associated with the attenuation of MSNA and not generated by gastric infusion of water at the same rate as in this drinking manner. In conclusion, the rapid rise in BP might be caused through stimulations from the oropharyngeal region, swallowing-induced factors, and/or a feedforward mechanism by a central descending signal from the higher brain centers. 相似文献
50.
Takashi Sekine Keiko Fukutani Tomiko Motegi Hiroshi Hayakawa Takashi Tamura Shigeo Nagafuchi Yutaka Nakahori Yasuo Nakagome 《Journal of human genetics》1992,37(2):157-162
Summary Results of DNA study on two patients of gonadal dysgenesis with a 45,X/46,X,Ynf (non-fluorescent Y chromosome) karyotype are described. In one patient who developed gonadoblastoma, all 12 loci on the non-fluorescent part of Yq were detected. Another patient did not have gonadoblastoma at 20 years, and only the proximal 6 loci out of 12 were detected. 相似文献