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231.
Ohmatsu H Higashi Y Nehashi S Kodama R Yoshizaki S Numai T 《Masui. The Japanese journal of anesthesiology》2007,56(11):1365-1367
A 46-year-old man suspected of spurious polycythemia received nephrectomy. Spurious polycythemia patients with high blood pressure as a complication have a high possibility of developing cerebral vascular disease. For its prevention, it is important to decrease blood viscosity by phlebotomy and to perform anticoagulation therapy. It is also necessary to deal with these patients as a high-risk group of cerebral vascular disease even if there is no symptoms. We were able to manage this case safely without any complication by aggressive perioperative phlebotomy and anticoagulation therapy. 相似文献
232.
Repeated or chronic stress is known to produce structural and functional changes in the rat brain, and in particular, alter the response of the hypothalamic–pituitary–adrenal (HPA) axis to subsequent new stress. Occlusal disharmony via placement of acryl cap on the lower incisors of rats is perceived as chronic stress. To determine the response of the HPA axis to subsequent new stress in rats with occlusal disharmony, we measured plasma corticosterone levels in these rats after subjecting them to new stress. Plasma corticosterone levels in rats with and without incisal cap increased and reached a peak 30 min after exposure to the new stress. However, a later decrease in plasma corticosterone levels from peak levels was found in rats with incisal cap compared with rats without incisal cap. This finding suggests that occlusal disharmony alters the response of the HPA axis to subsequent new stress. 相似文献
233.
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235.
Fang-Yen C Wyart M Xie J Kawai R Kodger T Chen S Wen Q Samuel AD 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(47):20323-20328
To navigate different environments, an animal must be able to adapt its locomotory gait to its physical surroundings. The nematode Caenorhabditis elegans, between swimming in water and crawling on surfaces, adapts its locomotory gait to surroundings that impose approximately 10,000-fold differences in mechanical resistance. Here we investigate this feat by studying the undulatory movements of C. elegans in Newtonian fluids spanning nearly five orders of magnitude in viscosity. In these fluids, the worm undulatory gait varies continuously with changes in external load: As load increases, both wavelength and frequency of undulation decrease. We also quantify the internal viscoelastic properties of the worm's body and their role in locomotory dynamics. We incorporate muscle activity, internal load, and external load into a biomechanical model of locomotion and show that (i) muscle power is nearly constant across changes in locomotory gait, and (ii) the onset of gait adaptation occurs as external load becomes comparable to internal load. During the swimming gait, which is evoked by small external loads, muscle power is primarily devoted to bending the worm's elastic body. During the crawling gait, evoked by large external loads, comparable muscle power is used to drive the external load and the elastic body. Our results suggest that C. elegans locomotory gait continuously adapts to external mechanical load in order to maintain propulsive thrust. 相似文献
236.
Koji Ikegami Showbu Sato Kenji Nakamura Lawrence E. Ostrowski Mitsutoshi Setou 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(23):10490-10495
Airway epithelial cilia protect the mammalian respiratory system from harmful inhaled materials by providing the force necessary for effective mucociliary clearance. Ciliary beating is asymmetric, composed of clearly distinguished effective and recovery strokes. Neither the importance of nor the essential components responsible for the beating asymmetry has been directly elucidated. We report here that the beating asymmetry is crucial for ciliary function and requires tubulin glutamylation, a unique posttranslational modification that is highly abundant in cilia. WT murine tracheal cilia have an axoneme-intrinsic structural curvature that points in the direction of effective strokes. The axonemal curvature was lost in tracheal cilia from mice with knockout of a tubulin glutamylation-performing enzyme, tubulin tyrosine ligase-like protein 1. Along with the loss of axonemal curvature, the axonemes and tracheal epithelial cilia from these knockout (KO) mice lost beating asymmetry. The loss of beating asymmetry resulted in a reduction of cilia-generated fluid flow in trachea from the KO mice. The KO mice displayed a significant accumulation of mucus in the nasal cavity, and also emitted frequent coughing- or sneezing-like noises. Thus, the beating asymmetry is important for airway ciliary function. Our find-ings provide evidence that tubulin glutamylation is essential for ciliary function through the regulation of beating asymmetry, and provides insight into the molecular basis underlying the beating asymmetry. 相似文献
237.
Toki A, Tamura R, Sumida M. Long-term ventilation for high-level tetraplegia: a report of 2 cases of noninvasive positive-pressure ventilation.Ventilator-dependent patients with tetraplegia rarely use noninvasive positive-pressure ventilation (NPPV) for long-term ventilation. We report 2 patients with high-level traumatic tetraplegia who were able to return home after being changed from traditional ventilation to NPPV. When they were referred to our hospital from acute care hospitals 2 to 6 months after injury, both were on tracheostomy ventilation with a cuff inflated 24 hours a day, and tidal volume (Vt) settings were low. In case 1, a man with complete C1 tetraplegia was admitted to our hospital 6 months after injury. We changed ventilator settings to high Vt and introduced NPPV. He was discharged home with NPPV with a volume-setting ventilator. Case 2 involved a man in his late twenties with complete C1 tetraplegia who was discharged home with NPPV. After discharge, he trained in glossopharyngeal breathing by himself, enabling him to breathe up to 1900mL of maximum insufflation capacity. Both have lived nearly 1 year without pulmonary complications in the community. They use visiting nurses 3 times a week and services of visiting caregivers. Further study is needed to determine the usefulness of NPPV for long-term ventilatory management. 相似文献
238.
Yoshizawa K Shirakawa H Ichijo T Umemura T Tanaka E Kiyosawa K Imagawa E Matsuda K Hidaka E Sano K Nakazawa Y Ikegami T Hashikura Y Miyagawa S Ota M Nakano M 《Clinical transplantation》2008,22(3):385-390
Abstract: Since first being described in 1998, de novo autoimmune hepatitis (AIH) after liver transplantation has been reported in several cases suffering from non-autoimmune liver diseases and primary biliary cirrhosis (PBC). Glutathione S-transferase (GST) T1 genotype mismatches between donor and recipient have also been suggested to constitute a risk factor for de novo AIH. Here, we report a 33-yr-old woman who presented complaining of marked fatigue and jaundice four yr after living-donor liver transplantation for PBC. On examination, transaminase levels were highly elevated and ANA and antimitochondrial antibody M2 were positive. Histological findings showed zonal necrosis with lymphoplasmacytic infiltration closely resembling AIH. She had pretreatment AIH score of 16 and 19 points after relapse of de novo AIH. Two color fluorescence in situ hybridization with X and Y chromosome-specific probes clearly revealed that the hepatocytes were of donor origin and lymphocytes were of patient origin. The GSTT1 genotype of the patient and the donor were the same null type, suggesting that mechanisms other than GSTT1 mismatches may exist in de novo AIH development. In conclusion, recipient immune cells attacked the allogeneic transplanted liver of the patient via de novo AIH, although the exact participation of autoimmune mechanisms is unclear. 相似文献
239.
Meguro M Soejima Y Taketomi A Ikegami T Yamashita Y Harada N Itoh S Hirata K Maehara Y 《Surgery today》2008,38(5):463-468
We herein present a case of unresectable giant hepatic hemangiomas with Kasabach-Merritt syndrome which was successfully treated
by living donor liver transplantation using a left lobe graft. The patient was a 45-year-old woman who complained of abdominal
distension. Two sessions of transarterial embolization were performed, but failed to reduce the size of the tumor. The hepatic
tumors were thus judged untreatable and the only option for a cure was to offer living donor liver transplantation, because
of the tumor size, its location, and the association with Kasabach-Merritt syndrome. A left lobe graft with the middle hepatic
vein donated by her 47-year-old brother was transplanted under venovenous bypass. The postoperative course of the recipient
was complicated by small-for-size graft syndrome, which developed after episodes of acute cellular rejection on postoperative
day 8 and sepsis on day 31. The patient successfully recovered from the complications and was discharged on day 72, and she
remains well at 10 months after transplantation. In conclusion, living donor liver transplantation was found to be an effective
option for the treatment of a patient with unresectable giant hepatic hemangiomas complicated by Kasabach-Merritt syndrome. 相似文献
240.
Nii A Shimada M Ikegami T Mori H Imura S Arakawa Y Morine Y Kanemura H 《Journal of Hepato-Biliary-Pancreatic Surgery》2008,15(5):522-527
BACKGROUND/PURPOSE: The efficacies of vessel sealing system (VSS) devices for major Glisson bundles and major bile ducts have not yet been determined. METHODS: Male pigs (n = 6) and a LigaSure V device and an Atlas 20 (Valleylab, Boulder, CO, USA) device were used in this study. After laparotomy, the common bile duct and the right and left first-degree Glisson bundles were sealed by the VSS. The lower and upper parts of the common bile ducts were also sealed. Macro-and microscopic examinations were performed for the analysis of specimens taken just after VSS application. In an analysis of bile duct specimens taken 1 week after the VSS application, both burst pressure tests and histological examinations were performed. RESULTS: (1) In the analysis of the specimens (Glisson bundles and bile ducts) obtained just after the VSS application, the macroscopic changes included permanent, flattened changes of the Glisson bundles and bile ducts, without showing any blood or bile leakage. Histological examination of the transverse sections of the Glisson bundle after VSS application revealed that not only the blood vessels but also the bile ducts were fused together. (2) In the analysis of the specimens (bile ducts) obtained 1 week after the VSS application, second-look laparotomy showed extrahepatic bile duct obstruction. The mean burst pressure of the sealed bile ducts was 74.4 +/- 20.1 mmHg. Histological examination revealed that the lumen of the bile duct was completely sealed and the duct was surrounded by dense connective tissues. CONCLUSIONS: The VSS is useful for the safe sealing of not only the major Glisson bundles but also the major bile ducts. 相似文献