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71.
Noboru Sakai Noriko Nishizawa Jun-ichi Matsushima Hideo Kurihara Takehiko Kokubun Ken-ichi Koichi Shiroh Maguchi Yukio Inuyama 《Artificial organs》1996,20(8):951-954
Abstract: To prevent side effects from a silicone shim in Isshiki thyroplasty type I, we used a ceramic shim in 10 patients with unilateral recurrent laryngeal nerve paralysis. No published reports have described the use of ceramic in this type of surgery. According to the degree of glottic insufficiency, ceramic shims of various heights were inserted into the fenestration made in the thyroid ala. All patients experienced subjective improvement of voice postoperatively. Laryngoscopies in most cases showed that glottic insufficiency improved postoperatively. In the postoperative examination, the maximum phonation time improved an average of 3.7 s, and the mean flow rate improved an average of 331 ml/s. We have analyzed the relationship of these improvements to the degree of glottic insufficiency and have compared our results with those of other investigators. 相似文献
72.
The effects of lung volume and respiratory airflow on airway resistance were studied in five anesthetized and paralyzed patients. Airway resistance measured during the inspiratory phase with intermittent constant airflow inflatoins decreased in inverse correlationship to increases in lung volume. Airway resistance measured during the expiratory phase with an airway interruption technique, on the other hand, increased with a linear relationship to the expiratory airflow as expressed by a function of Y = K1 + K2X. K1, calculated from the values of airway resistance corresponding to three different airflows, was unaffected by intentional expiratory resistance loading. Thus, simultaneously with the measurement of airway resistance by this method, expiratory gas sampling with a Douglas bag can be done if necessary. Since the K2 value of the endotracheal tube used in this study (Portex® I.D. 8mm, length 26cm) was quite high (5.0cmH2O·1–2·sec2), depending on the airflow, the presence of the endotracheal tube strongly affected the measurement of airway resistance during general anesthesia. K1 measured by the above method, however, may be considered as the best way to evaluate the lower airway resistance independent of either lung volume or expiratory airflow.(Sakai T, Yoshida H, Yano H et al.: Measurement of airway resistance in anesthetized and paralyzed subjects: proposal for evaluation of K1 values. J Anesth 2: 139–145, 1988) 相似文献
73.
T Kitade Y Odahara S Shinohara T Ikeuchi T Sakai K Morikawa M Minamikawa S Toyota A Kawachi M Hyodo 《Acupuncture & electro-therapeutics research》1988,13(2-3):87-97
It has been claimed that the mechanism of acupuncture analgesia can be explained in part by endogenous opioids. If so, it might be possible to enhance the analgesic effect of acupuncture by the administration of endorphins. If D-phenylalanine (DPA), an inhibitor of the endorphin degrading enzyme, is administered, the analgesic effect of acupuncture should be prolonged due to the increased level of endorphins. From the changes of the pain threshold (PT), we investigated whether or not the pre-administration of DPA can enhance the analgesic effect of acupuncture in humans. In addition, we examined the inhibitory effect of naloxone. 1) In all five subjects whose PT was raised after acupuncture anesthesia (respondents), the rise in PT was significantly prolonged by DPA. 2) Out of 10 subjects whose PT remained almost unchanged after acupuncture anesthesia (non-respondents), the PT was increased by DPA in 5 cases. 3) The rise in PT was most prominent when DPA was administered 30 minutes before the start of acupuncture anesthesia. 4) In all 4 respondents in whom the rise in PT persisted after DPA and acupuncture anesthesia, their raised PT dropped after the intravenous injection of naloxone (10 mg). 5) These findings show that DPA enhances the analgesic effect of acupuncture by the "endorphin mechanism." 相似文献
74.
Two patients with "my hand" sign in association with tactile extinction from callosal lesion, one due to left anterior cerebral artery occlusion, the other due to right anterior cerebral artery aneurysm rupture, were reported. The examination of "my hand" sign was performed with the methods proposed by Brion et al. Our patients correctly responded when they grasped their own or the examiner's thumb with their left hand. But they replied "my finger"when they grasped not only their own but also the examiner's thumb with their right hand. Left tactile extinction was observed after a routine extinction test in one patient, and it was observed in the other after the following method: both patient's index fingers were disposed in his midline position. In these methods of extinction test, they made errors in saying "right" when both fingers were touched simultaneously. However, they said "both" when their right index finger alone was touched (synchiria) during an extinction test using the following method: both index fingers of patients were approached by examiner to touch each other or for one of them to touch the examiner's finger. When they were asked whose finger they touched in this method (whose finger test), they made the same errors as seen in "my hand" sign test. These test results suggest that there is a common underlying mechanism in the "my hand" sign and extinction, because the sense of double stimulations felt when only one stimulation is given (synchiria), is a possible explanation for the "my hand" sign and the pathogenesis of synchiria appears to be related to extinction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
75.
Long-term effect of urokinase therapy in IgA nephropathy 总被引:4,自引:0,他引:4
Effects of urokinase (UK) therapy in patients with moderate to advanced degrees of IgA nephropathy (IgAN) were examined. Twenty-seven patients were treated by "two weeks" UK administration, 14 patients were treated by "consecutive" UK administration and 16 patients were treated by antiplatelet drugs. There were marked improvements in urinary protein concentration, serum creatinine and blood urea nitrogen after UK therapy, especially in patients treated by "consecutive" UK administration which was performed by "single shot" UK injection. Clinical prognosis was favorable in patients treated by UK administration compared with those given antiplatelet treatment. It was concluded that "consecutive" UK administration might be useful for treatment of IgAN with moderate to advanced renal injuries. 相似文献
76.
Activation of protease-activated receptor 2 stimulates proliferation and interleukin (IL)-6 and IL-8 secretion of endometriotic stromal cells 总被引:3,自引:0,他引:3
Hirota Y Osuga Y Hirata T Harada M Morimoto C Yoshino O Koga K Yano T Tsutsumi O Taketani Y 《Human reproduction (Oxford, England)》2005,20(12):3547-3553
BACKGROUND: Inflammation has been proposed to play essential roles in the pathophysiology of endometriosis, in which neutrophils and mast cells have been suggested to be involved. We studied whether the protease-activated receptor 2 (PAR2), which is activated by enzymes from neutrophils and mast cells, in endometriotic stromal cells (ESC) has any implication in the development of the disease. METHODS: Cultured ESC were stimulated with various concentrations of a specific PAR2 agonist peptide. Proliferating activity of the cells was determined using immunostaining of proliferating cell nuclear antigen (a cell proliferation marker), 5-bromo-2'-deoxyuridine incorporation into DNA and cell count. The concentrations of interleukin (IL)-6 and IL-8 were measured using specific enzyme-linked immunosorbent assay kits. The phosphorylation of three mitogen-activated protein kinases (MAPK), i.e. p38 MAPK, p42/44 MAPK and stress-activated protein Kinase/c-jun N terminal Kinase, in ESC was examined with Western blot analysis. RESULTS: Activation of PAR2 stimulated the proliferation of ESC and the secretion of IL-6 and IL-8 from ESC in a dose-dependent manner. Activation of PAR2 stimulated the phosphorylation of all three MAPK, and inhibitors of each MAPK suppressed the PAR2 activation-induced proliferation of ESC. CONCLUSIONS: The activation of PAR2 in ESC may be involved in the pathophysiology of endometriosis by inducing the growth and inflammation of endometriotic lesions. 相似文献
77.
Katsumi Inoue Kenichi Abe Kenji Ando Shinichi Shirai Kei Nishiyama Michio Nakanishi Takashi Yamada Koyu Sakai Yoshihisa Nakagawa Naoya Hamasaki Takeshi Kimura Masakiyo Nobuyoshi Tadaomi Alfonso Miyamoto 《Cardiovascular pathology》2004,13(2):109-115
BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability. 相似文献
78.
Osamu Sakai Yasuhide Nakayama Yasushi Nemoto Yoshihiro Okamoto Taiji Watanabe Keiichi Kanda Hitoshi Yaku 《Journal of artificial organs》2005,8(2):119-124
A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application. 相似文献
79.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
80.
Miwa N Hayakawa S Miyazaki S Myojo S Sasaki Y Sakai M Takikawa O Saito S 《Molecular human reproduction》2005,11(12):865-870
Recent data demonstrated that CD4+CD25+ regulatory T (Treg) cells and an enzyme called indoleamine 2,3-dioxygenase (IDO) mediate maternal tolerance to the fetus. Interestingly, Treg cells express the CTLA-4 molecule on their surface, and B7 (CD80/86) ligation by CTLA-4 enhanced IDO activity of dendritic cells (DCs) and monocytes by the induction of interferon gamma (IFN-gamma) production. In this study, we studied the IDO expression on peripheral blood monocytes and decidual monocytes or DCs after treatment with CTLA-4/Fc fusion protein or IFN-gamma using flow cytometry. IDO expressions on both peripheral blood DC and decidual DC and monocytes were up-regulated during normal pregnancy. On the other hand, both IDO expression on DC and monocytes after IFN-gamma treatment or CTLA-4 treatment were decreased in spontaneous abortion cases. The expression of CD86 on peripheral blood and decidual monocytes and DC in spontaneous abortion cases was lower compared with those in normal pregnancy subjects. Also, IFN-gamma production by decidual and peripheral blood mononuclear cells after CTLA-4/Fc treatment in spontaneous abortion cases was significantly lower than those in normal pregnancy subjects. These data suggest that CTLA-4 on Treg cells up-regulates IDO expression on decidual and peripheral blood DC and monocytes by the induction of IFN-gamma production. 相似文献