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71.
目的:检测γ-氨基丁酸(gamma-aminobutyricacid,GABA)和谷氨酸脱羧酶(glutamicaciddecarboxylase,GAD)在大鼠降结肠上皮的表达及分布特征,并探讨GABA与上皮细胞分化增殖的关系.方法:用免疫荧光及激光共聚焦显微扫描技术,检测GABA、GAD65及GAD67在大鼠降结肠上皮中的表达,并以麦芽凝聚素组织化学染色与免疫荧光结合的双重染色显示GABA和GAD65表达细胞的分布特征.同时,用RT-PCR和原位分子杂交方法检测GADmRNA的表达.此外,用3H-胸腺嘧啶放射自显影法显示降结肠上皮的增殖带.结果:RT-PCR显示降结肠黏膜中GAD65及GAD67mRNA均阳性,原位杂交显示阳性杂交信号主要分布在上皮细胞的隐窝和腔面,且GAD65信号较GAD67强.GABA及GAD65免疫反应阳性细胞主要分布在降结肠的腔面和隐窝的上1/3上皮细胞的胞质,而GAD67阳性细胞仅分布腔面,此外,GABA及GAD65阳性染色也见于黏膜固有层.双重染色显示杯状细胞中GABA及GAD65均阴性.3H-胸腺嘧啶标记阳性细胞主要在隐窝的中下段.结论:GABA及GAD65分布在大鼠降结肠上皮的成熟带及功能带,GABA系统可能参与上皮细胞的分化与增殖的调节. 相似文献
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74.
Keita Kano Kahori Kawamura Tatsuro Miyake 《Medicina oral, patología oral y cirugía bucal》2021,26(1):e64
Background The efficacy of preemptive analgesia in managing postoperative pain remains controversial. The aim of this study was to compare the efficacy of intravenous (IV) acetaminophen administered before or immediately after the surgical extraction of an impacted mandibular third molar. Material and Methods This prospective randomized clinical trial included 120 patients. The patients were assigned to one of three groups: the preoperative-treatment group (pre-group), which received 1000 mg of IV acetaminophen 20 min before surgery; the postoperative-treatment group (post-group), which received 1000 mg of IV acetaminophen after surgery; the no-treatment group (control-group), which did not receive any analgesic. Rescue analgesic (60 mg loxoprofen) was issued to each patient, with instructions on self-administration if needed. For the rescue medication usage, the time of first loxoprofen usage and the total amount of loxoprofen consumption were obtained for a 17-hour period after surgery. We measured pain using the visual analogue scale at 1 hour and at 2, 3, 4, 5, and 15 hours after surgery. Results There was no significant difference in pain level among the three groups at any time interval. However, the pre-group demonstrated significantly lower rescue analgesic consumption and longer time until initial administration. Conclusions Administration of IV acetaminophen before third molar surgery provides more effective pain control than postoperative administration and no treatment. Key words:Preemptive analgesia, acetaminophen, impacted third molar, pain relief, randomized controlled trial. 相似文献
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76.
In situ Ca2+ dynamics of Purkinje fibers and its interconnection with subjacent ventricular myocytes
Hamamoto T Tanaka H Mani H Tanabe T Fujiwara K Nakagami T Horie M Oyamada M Takamatsu T 《Journal of molecular and cellular cardiology》2005,38(4):561-569
Purkinje fibers play essential roles in impulse propagation to the ventricles, and their functional impairment can become arrhythmogenic. However, little is known about precise spatiotemporal pattern(s) of interconnection between Purkinje-fiber network and the underlying ventricular myocardium within the heart. To address this issue, we simultaneously visualized intracellular Ca(2+) dynamics at Purkinje fibers and subjacent ventricular myocytes in Langendorff-perfused rat hearts using multi-pinhole type, rapid-scanning confocal microscopy. Under recording of electrocardiogram at room temperature spatiotemporal changes in fluo3-fluorescence intensity were visualized on the subendocardial region of the right-ventricular septum. Staining of the heart with either fluo3, acetylthiocholine iodide (ATCHI), or di-4-ANEPPS revealed characteristic structures of Purkinje fibers. During sinus rhythm (about 60 bpm) or atrial pacing (up to 3 Hz) each Purkinje-fiber exhibited spatiotemporally synchronous Ca(2+) transients nearly simultaneously to ventricular excitation. Ca(2+) transients in individual fibers were still synchronized within the Purkinje-fiber network not only under high-K(+) (8 mM) perfusion-induced Purkinje-to-ventricular (P-V) conduction delay, but also under unidirectional, orthodromic P-V block produced by 10-mM K(+) perfusion. While spontaneous, asynchronous intracellular Ca(2+) waves were identified in injured fibers of Purkinje network locally, surrounding fibers still exhibited Ca(2+) transients synchronously to ventricular excitation. In summary, these results are the first demonstration of intracellular Ca(2+) dynamics in the Purkinje-fiber network in situ. The synchronous Ca(2+) transients, preserved even under P-V conduction disturbances or under emergence of Ca(2+) waves, imply a syncytial role of Purkinje fibers as a specialized conduction system, whereas unidirectional block at P-V junctions indicates a substrate for reentrant arrhythmias. 相似文献
77.
Motoyasu Ishii Yutaka Miyazaki Takeshi Yamamoto Masahito Miura Yoshiyuki Ueno Tohru Takahashi Takayoshi Toyota 《Liver international》1993,13(4):227-231
ABSTRACT— A 50-year-old woman suffered from a diffuse skin rash, high fever and jaundice immediately after a second injection of glutathion and Stronger Neo-minophagen C which contains glycyrrhizin. Liver biopsy performed 11 months after the onset showed mild spotty hepatocyte necrosis, marked cholestasis in parenchyma, and some lymphocyte infiltration in the portal area. Interlobular bile ducts had undergone vacuolar degeneration or were absent in some portal tracts. In her hospital course, unremitting jaundice persisted and biliary cirrhosis developed with signs of portal hypertension; she died from liver failure 26 months after the onset. A liver specimen at her death revealed that most of the interlobular bile ducts had vanished. Based on the clinical course and pathology, drug-induced ductopenia, possibly due to an adverse reaction to glycyrrhizin, is the most likely diagnosis. While drug-related biliary cirrhosis is rarely fatal, this case presented an unusually rapid course of fatal biliary cirrhosis. 相似文献
78.
Clinical outcome of endoscopic aspiration mucosectomy for early stage gastric cancer 总被引:10,自引:0,他引:10
Tanabe S Koizumi W Mitomi H Nakai H Murakami S Nagaba S Kida M Oida M Saigenji K 《Gastrointestinal endoscopy》2002,56(5):708-713
BACKGROUND: Endoscopic mucosal resection is an established treatment option for early stage gastric cancer. However, several problems with endoscopic mucosal resection remain to be solved, such as appropriate treatment for recurrence and incomplete tumor resection. The outcome for patients undergoing endoscopic aspiration mucosectomy (endoscopic mucosal resection) by a modification of the cap-fitted technique was evaluated retrospectively to determine factors associated with complete resection and tumor recurrence. METHODS: Endoscopic mucosal resection was performed in 106 patients with early stage gastric cancers up to 20 mm in diameter that were well or moderately differentiated adenocarcinoma. All were superficial lesions without ulceration, distinct signs of submucosal invasion, or a poorly demarcated border. En bloc (tumors <10 mm in diameter) or piecemeal (tumors 10-20 mm in diameter) resection was performed. Follow-up endoscopy was performed at 2, 6, 12, 18, and 24 months and thereafter once per year. Outcome and factors associated with complete resection and tumor recurrence were assessed retrospectively. RESULTS: Sixty-eight patients (64%) underwent en bloc resection and 38 (36%) piecemeal resection. The mean longest dimension (SD) of the resected lesions was significantly greater after piecemeal resection (12.3 [4.0] mm) than after en bloc resection (7.6 [4.0] mm; p < 0.01). In patients with tumors completely resected, there was no recurrence after either en bloc or piecemeal resection. Six of 8 patients found to have submucosal invasion after endoscopic mucosal resection underwent surgery. Patients with incompletely resected intramucosal lesions underwent additional endoscopic treatment. Cancer recurred in 3 patients (2.8%), all of whom had lesions measuring more than 15 mm in diameter. CONCLUSIONS: Endoscopic mucosal resection is safe and useful for the management of early stage gastric cancer. Further improvement in outcome requires more accurate preoperative diagnosis and postoperative histopathologic evaluation. Patients with incompletely resected lesions should undergo aggressive additional treatment. 相似文献
79.
Keisuke Itotani Masahito Murakami Motoko Itotani Atsushi Nagai Yuzo Imabori Kazuyuki Fujimoto Mamoru Tanaka Junichi Kato 《Journal of Physical Therapy Science》2015,27(2):321-323
[Purpose] This study investigated the association between the weight-bearing ratio (WBR)
and gait ability of a paretic lower limb while walking using a shoe-type load-measuring
apparatus. [Subjects] The Subjects comprised 17 stroke patients who were classified into
the following two groups: the independent walking group, and the non-independent walking
group. [Methods] The 10-m walking time (inside and outside parallel bars) and the Berg
Balance Scale (BBS) were measured. The WBR of the paretic lower limb was measured during
static standing and while walking inside and outside parallel bars, and the coefficient of
variation (CV) was calculated. WBR was evaluated using the Step Aid. [Results] The BBS and
WBR were significantly decreased in the non-independent walking group, while the 10-m
walking time and the CV were significantly increased in the non-independent walking group.
[Conclusion] The CV and WBR of a paretic lower limb while walking appear to be important
indices of achievement of independent gait in hemiplegic stroke patients, and they may be
used in gait rehabilitation for diseases requiring weight-bearing training to follow the
course of training using a shoe-type load-measuring apparatus.Key words: Stroke, Weight-bearing ratio, Shoe-type load-measuring apparatus 相似文献
80.
Treatment of elderly patients with early gastric cancer by endoscopic submucosal dissection using an insulated-tip diathermic knife 总被引:3,自引:0,他引:3
Hirasaki S Tanimizu M Nasu J Shinji T Koide N 《Internal medicine (Tokyo, Japan)》2005,44(10):1033-1038
OBJECTIVE: In recent years, the number of elderly patients with early gastric cancer (EGC) has steadily been increasing. In our institute, endoscopic submucosal dissection (ESD) involving the use of an insulated-tip diathermic knife (IT-ESD) was introduced for the treatment of mucosal gastric carcinoma in 1996. The purpose of this study was to evaluate the effectiveness of IT-ESD for the treatment of elderly patients with EGC. MATERIALS AND METHODS: A total of 144 patients with EGC were treated at Shikoku Cancer Center in the 5-year period from January 2000 to December 2004, including 53 patients over 75 years old. The performance status (PS) for all patients was less than 2. We compared patient's backgrounds, the one-piece resection rate, complete resection (CR) rate, operation time, bleeding rate, perforation rate, blood pressure, and peripheral oxygen saturation (SpO(2)) between patients over 75 years of age (elderly group) and the remaining 91 younger patients (non-elderly group). RESULTS: The rate of having underlying disease was significantly higher for the elderly group (p<0.05) and we found no significant difference for the one-piece resection rate, CR rate, operation time, bleeding rate, and perforation rate between the 2 groups. There were also no significant differences for the frequency of the use of oxygen, pressor and depressor between the 2 groups. CONCLUSION: There was no significant difference in the outcome resulting from ESD between the 2 groups. Our study proves that ESD is a feasible treatment for elderly patients with EGC PS of less than 2. 相似文献