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Ryo Wakita Yuka Ohno Saori Yamazaki Hikaru Kohase Masahiro Umino 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(6):e28-e32
Two cases of vasovagal syncope (VVS) during venous access are reported. Both patients had a history of fainting episodes and experienced bradycardia with asystole, hypotension, and fainting. Pain and phobic stress during venous access triggered an increase in parasympathetic tone, resulting in bradycardia with asystole and hypotension in both cases. Hypotension and bradycardia likely caused cerebral hypoperfusion, leading to fainting. The intense parasympathetic tone triggered by somatic or emotional stress was likely responsible for directly depressing the sinus node, leading to asystole and bradycardia. Bradycardia with asystole progressing to syncope is a potentially fatal dysrhythmia in patients with cardiovascular disease or older patients with decreased cardiac function. Appropriate treatment for VVS includes the administration of intravenous fluids, vagolytics, ephedrine, and the rapid use of the Trendelenburg position. Intravenous fluids and atropine were used to treat the present patients. 相似文献
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Yoshinobu Okabe Osamu Tsuruta Yoshiki Naito Hideya Suga Michio Sata 《Digestive endoscopy》2007,19(Z1):S121-S125
Regarding peroral cholangioscopy (POCS) for biliary disease, due to the recent appearance of a video cholangioscope that can obtain high‐quality images, it is possible to observe subtle changes of the biliary mucosa. In addition to the conventional observation method using POCS, the biliary mucosa with also observed with narrow band imaging (NBI) in one case of chronic cholangitis and four cases of extra hepatic bile duct tumor (three surgical cases). In the conventional observation method, the vessels in the surface layer of the biliary mucosa could be observed more clearly using NBI. In one case in which a tumor was observed, the irregularity of the biliary mucosa became clear on NBI, and the vessels inside a papillary tumor could also be easily observed. In another case of bile duct tumor, the conventional observation method showed a region in the proximity of the tumor where the vessels could not be seen clearly, but they could be seen clearly on NBI. In all of the cases, the bile juice was seen as red on NBI, which disturbed the observation. With POCS using NBI, it was possible to observe the vessels and irregularities in the surface layer of the biliary mucosa more clearly than with conventional observation methods. 相似文献
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Masafumi Fujimoto Tuneaki Sakata Yuji Tsuruta Shoji Iwagami Hiroshi Teraoka Shin-ichi Mihara Yonetaka Fukiishi Misao Ide 《Biochemical pharmacology》1990,40(12):2661-2670
Bradykinin-stimulated prostacyclin synthesis in porcine aortic endothelial cells was enhanced by pretreatment of the cells with pertussis toxin or islet-activating protein (IAP) for 5 hr or longer. Although ADP-ribosylation of a protein with a molecular weight of 41–42 kD in the cell membranes was completed by 3 hr after the addition of IAP into the incubation medium, there was good correlation between enhancement of bradykinin-induced prostacyclin synthesis and ADP-ribosylation of the IAP substrate over a wide range of IAP concentrations. Furthermore, even if IAP was removed from the incubation medium at 3 hr, bradykinin-induced prostaglandin synthesis at 24 hr was still potentiated. Cycloheximide and actinomycin D enhanced bradykinin-induced prostacyclin synthesis and apparently blocked the effect of IAP. Since this result suggested the involvement of an inhibitor protein(s) of prostacyclin synthesis in the IAP effect, we studied the effect of IAP on the level of lipocortin I which is known to inhibit phospholipase A2. Western and Northern blot analyses revealed that IAP decreased the amounts of protein and mRNA of lipocortin I. These results suggest that the enhancement of bradykinin-induced prostacyclin synthesis by IAP is associated with a decrease in the level of lipocortin I. 相似文献
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Attenuation of lung injury in allograft rejection using NF-kappaB decoy transfection-novel strategy for use in lung transplantation. 总被引:5,自引:0,他引:5
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Mariko Hosono H. Kobayashi Ryota Fujimoto Kazushige Tsutsui Yoshihiko Kotoura Tadao Tsuboyama Hikaru Hayashi Takashi Nakamura Junji Konishi 《Skeletal radiology》1997,26(9):525-528
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with
plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast
T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense
rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have
this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant
disease, so as not to misinterpret it as a chondroid tumor or bone metastasis. 相似文献
9.
Akihiro Hagiwara Masashi Sano Emiko Asakawa Hikaru Tanaka Ryohei Hasegawa Nobuyuki Ito 《Cancer science》1992,83(9):949-954
The modifying potential of two nephrotoxic agents, harman and norharman, on N-ethyl-N-hydroxyethylnitrosamine (EHEN)-induced renal and hepatic carcinogenesis was investigated in male F344/DuCrj rats. Animals were given 0.1% EHEN in their drinking water for the first 2 weeks as an initiator. Subsequently, starting 3 weeks from the commencement, they were fed diet containing these compounds at concentrations of 1000, S00 or 0 ppm until week 26, and then killed for light microscopic examination. The mean numbers of renal tubular cell hyperplasias/cm2 and those of tumors/cm2 in rats given harman and norharman at 1000 ppm after initiation, but not at 500 ppm, were significantly increased as compared to the control values. However, neither compound modified liver carcinogenesis. It is concluded that harman and norharman show enhancing effects on rat kidney carcinogenesis, when ingested at dose levels which cause renal tubular damage. 相似文献
10.
In order to investigate how the ganglia in ganglionated plexus were distributed throughout the overall region of the gallbladder, the gallbladder was dissected from guinea-pig and washed with Krebs solution via the cystic duct. This gallbladder was distended with 2 ml of the mixed solution of OsO4 and ZnI2 injected with a syringe via the cystic duct and the cystic duct was immediately tied with a thread. The gallbladder was placed in excess of the mixed solution for 7-10 hours. The gallbladder was longitudinally divided into two approximately equal parts and each was prepared for microscopic investigation. The one preparation was the ventral side of the gallbladder and the other preparation was its dorsal side. These preparations were viewed through a photomicroscope. The obtained results were as follows: 1. Ganglia which involved several nerve cells were observed. Ganglia and nerve bundles connecting the fellow ganglia formed an irregular network, that is, the so-called ganglionated plexus. These nerve bundles were connected with the perivascular nerves which ran parallel to and around blood vessels in several places of the wall of the gallbladder. 2. Ganglia were full of variety in size and shape. That is to say, the shape of ganglia is arranged in various patterns such as oval, spherical, triangular, square and so on. When the size of ganglia were shown by surface area of ganglia which were viewed within the sweep of photomicroscope, the size of ganglia were divided into three large groups, the small ganglia in the range of 1,400 microns2-3,500 microns 2, the large ganglia in the range of 3,500 microns2-10,000 microns2 and the extra-large ganglia in the range of 10,000 microns2-38,000 microns2. Per one gallbladder, 240 +/- 41 (n = 3) small ganglia, 263 +/- 28 (n = 3) large ganglia and 8 +/- 1 (n = 3) extra-large ganglia were found. And these ganglia were irregularly scattered all over the wall of gallbladder. Small ganglia were found more numerous than large ganglia in the cervical portion of the gallbladder. On the other hand, small ones were slightly fewer than large ganglia in the remainder portion of the gallbladder. 3. The ganglionated plexus contained 511 +/- 69 (n = 3) ganglia.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献