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91.
马庆久  石景森  要秀  邱随民  罗健 《医学争鸣》2002,23(21):1926-1928
目的 探讨耳穴脉冲电刺激治疗胆石症 ,胆绞痛的机制 .方法 选用 15条成年杂种犬 ,进行耳穴体表脉冲刺激与缩胆素 (CCK)对在体狗胆囊张力 ,Oddi括约肌张力及肌电活动影响的对比研究 .结果 耳穴脉冲电刺激对胆囊张力无明显影响 [(1.2 7± 0 .2 6 ) k Pa与 (1.2 4± 0 .2 2 ) k Pa,P<0 .0 5 ],CCK注射液能明显提高胆囊张力 [(1.2 7± 0 .2 6 ) k Pa与 (1.91± 0 .39) k Pa,P<0 .0 5 ],CCK注射液能明显降低Oddi括约肌张力 [(2 .2 4± 0 .5 5 ) k Pa与 (1.5 8± 0 .5 6 ) k Pa,P>0 .0 5 ]及肌电活动 .结论 耳穴脉冲电刺激同 CCK一样 ,均对 Oddi括约肌的张力有显著的降低作用 ,并减少 Oddi括约肌的肌电峰电位爆发波的频率与电压值 ,推测其对胆绞痛有治疗作用 ,并有助于胆结石的排石过程 .  相似文献   
92.
庆大霉素对豚鼠前庭上皮IGF-1及其受体表达的影响   总被引:1,自引:0,他引:1  
目的:研究庆大霉素对豚鼠前庭上皮胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)及其受体(insulin-like growth factor-1 receptor,EGF-1R)表达的影响,并探讨其生物学特性。方法:采用免疫组织细胞化学方法,以抗IGF-1及IGF-1R抗体为标记物,检测庆大霉素损伤后豚鼠前庭上皮自发修复期IGF-1及IGF-1R的表达变化和分布特点;采用Brdu体内标记和抗Brdu抗体免疫组化染色,检测庆大霉素损伤后豚鼠前庭上皮增殖的变化。结果:IGF-1及IGF-1R在正常成年豚鼠前庭上皮细胞中有低水平表达,庆大霉素损伤后,其表达增多。在1d组IGF-1及IGF-1R表达最强,其后逐渐减少。在正常对照组中无Brdu阳性细胞。各实验组均观察到Brdu阳性细胞,7d组最多。结论:庆大霉素损伤后,豚鼠前庭上皮IGF-1及IGF-1R表达增强,其时程变化与细胞增殖活动密切相关。IGF-1在豚鼠前庭上皮损伤后的细胞增殖中可能起重要信号转导作用。  相似文献   
93.
94.
We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers.  相似文献   
95.
PURPOSETo use functional MR imaging to measure the effect of frequency (pitch), intensity (loudness), and complexity of auditory stimuli on activation in the primary and secondary auditory cortexes.METHODSMultiplanar echo-planar images were acquired in healthy subjects with normal hearing to whom auditory stimuli were presented intermittently. Functional images were processed from the echo-planar images with conventional postprocessing methods. The stimuli included pure tones with a single frequency and intensity, pure tones with the frequency stepped between 1,000, 2,000, 3,000, or 4,000 Hz, and spoken text. The pixels activated by each task in the transverse temporal gyrus (TTG) and the auditory association areas were tabulated.RESULTSThe pure tone task activated the TTG. The 1,000-Hz tone activated significantly more pixels in the TTG than did the 4,000-Hz tone. The 4,000-Hz tone activated pixels primarily in the medial TTG, whereas the 1,000-Hz tone activated more pixels in the lateral TTG. Higher intensity tones activated significantly more pixels than did lower intensity tones at the same frequency. The stepped tones activated more pixels than the pure tones, but the difference was not significant. The text task produced significantly more activation than did the pure tones in the TTG and in the auditory association areas. The more complex tasks (stepped tones and listening to text) tended to activate more pixels in the left hemisphere than in the right, whereas the simpler tasks activated similar numbers of pixels in each hemisphere.CONCLUSIONAuditory stimuli activate the TTG and the association areas. Activation in the primary auditory cortex depends on frequency, intensity, and complexity of the auditory stimulus. Activation of the auditory association areas requires more complex auditory stimuli, such as the stepped tone task or text reading.  相似文献   
96.
为探讨钙调素在慢性缺氧性肺动脉高压发病中的作用,将40只Wistar大鼠随机分为四组,I组为正常对照组,不接受任何处理。Ⅱ、Ⅲ、Ⅳ组为实验组,分别间断缺氧1、2、3周,而后采用火焰原子吸收分光光度法及磷酸二酯酶法测定四组大鼠肺组织Ca^2+含量及CaM活性。  相似文献   
97.
本文报道了我院收治的卵巢恶性畸胎瘤31例,随访中2例失访,随访率为93.53%。并讨论了卵巢恶性畸瘤的治疗方式为手术加联合化疗,对年轻的I期患者可行患侧单侧附件切除术,术后化疗极为重要。化疗方法采用VAC或PVB方案联合化疗,本文还 影响预后的重要因素为临床分期期和病理学特点.  相似文献   
98.
Eighty-nine cases of chronic bronchitis were matched against167 asymptomatic controls from the glass bangle industry ofFirozabad. Factors of age, social status, smoking habit andduration of exposure were studied. Duration of exposure wasfound to be a factor contributing significantly to the causationof disease. Requests for reprints should be addressed to: Dr B. N. Gupta, Division of Epidemilogy, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow P.O. Box 80, 226001, India  相似文献   
99.
BACKGROUND: Biliary tract lesions pose a dreaded complication of laparoscopic cholecystectomy. In a retrospective study we analyzed the clinical presentation, diagnostic and therapeutic management and outcome of 28 patients presenting with iatrogenic bile duct injuries. PATIENTS AND METHODS: Between 1994 and 2001 we treated 28 patients with bile duct lesions following laparoscopic cholecystectomy at our center. Operation notes and charts of all patients were reviewed systematically. A follow-up examination of each patient was performed after a median of 12 months (range 1-90). RESULTS: Twenty-two patients presented with major circumferential bile duct defect lesions. Less severe injuries (n=6) were two minor bile leaks, one bile duct stricture and three tangential lesions. Twenty-six patients were referred to our institution within 16 days (range 0-226 days). Six patients were treated by nonsurgical procedures: endoscopic stenting in four and percutaneous intervention in two. In one of the remaining patients a cystic duct leak was closed via laparotomy, and in 21 a hepaticojejunostomy was performed. Reconstruction of a hepaticojenunostomy was performed in two of these patients. Patients were dismissed from the hospital after a median of 13 days (range 4-156). Four patients presenting with generalized biliary peritonitis required prolonged intensive care. One or more episodes of cholangitis were seen in five patients during follow-up examinations. CONCLUSIONS: Major iatrogenic bile duct injuries are associated with high morbidity and prolonged hospitalization. Interdisciplinary cooperation and early referral to an experienced center is crucial in the management of patients suffering from this affliction. Cholangitis is a marked problem in the follow-up.  相似文献   
100.
棕榈油对成人血脂和血小板功能的影响   总被引:3,自引:0,他引:3  
张坚  王春荣 《营养学报》1997,19(2):186-190
报道了棕榈油(PA),花生油(PE)对血清总胆固醇水平(TC)在5.5~7.0mmol/L的受试者血脂和血小板功能的影响。51名受试者(男31人,女20人,年龄30~66岁之间)分为两组,一组男15人,女11人,称PE组;另一组男16人女9人,称PA组,预备期3周,膳食以当地日常食用的花生油烹调,实验期6周。PA组受试者食用以棕榈油烹调的实验膳;PE组受试者仍食花生油烹调的膳食。脂肪约占膳食能量的30%,其中60%~65%来自实验油。实验结果表明:与起始值相比,6周末PA组受试者血清TC,低密度脂蛋白胆固醇(LDL-C)和总胆固醇与高密度脂蛋白胆固醇比值(TC/HDL-C)显著下降,血浆血栓素B2(TXB2)/6-酮前列环素F1α、(6-keto-PGF1α)比值显著下降,全血血小板聚集率未见显著变化。PE组受试者的血脂、血浆TXB2、6-keto-PGF1α及全血血小板聚集率等指标均未出现显著变化。提示,棕榈油作为我国居民家庭烹调用油并不会增加发生心血管疾病的危险。  相似文献   
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