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121.
To evaluate the sensitivity of a polymerase chain reaction (PCR) assay using nested primers in detectingHelicobacter pylori, gastric tissue biopsy specimens were collected on endoscopy from 17 patients with a duodenal ulcer. DNA was extracted by phenol/chloroform treatment or boiling in water, and then subjected to a nested PCR using two primer pairs from the urease gene ofHelicobacter pylori. Fourteen of the 17 patients were positive forHelicobacter pylori using DNA samples extracted by either method. The PCR results correlated well with the results of an enzyme immunoassay to detect IgG antibody. However, there were two culture negative patients. The three PCR negative patients were both culture negative and serologically negative. DNA from 9 of the 14 patients was randomly selected and subjected to semiquantification by serial dilutions, and then PCR. The results showed that phenol/chloroform extraction yielded 10–1000 times more DNA than the boiling method. It is concluded that the PCR assay is a rapid and sensitive method for detectingHelicobacter pylori, and that phenol/chloroform extraction is superior to simple boiling in obtaining DNA samples for PCR.  相似文献   
122.
本文根据Svennerholm和蒋谷人等的方法略加改良,测定了蚌埠地区113例正常人,71例恶性肿瘤患者和82例非肿瘤疾病患者血清脂质结合唾液酸(LSA)的含量。正常值为12.4mg/dl(SD=±3.6mg/dl),71例不同肿瘤患者的平均值为28.2mg/dl(SD=±9.7mg/dl),阳性率为88.7%,82例非肿瘤疾病患者的平均值为16.82mg/dl(SD=±5.4mg/dl),假阳性率为17%。方法的灵敏度,重复性(平均CV=3.6%)和回收率(平均回收率=101.4%)测定结果是满意的。本研究的初步结果表明,血清LSA测定对肺癌、白血病、胃癌和食管癌具有一定的临床诊断价值。  相似文献   
123.
Twenty-one patients, under 6 years of age, with root avulsion of the brachial plexus were treated from 1975 to 1987. Among them, 9 had root avulsion of the upper trunk, 2 root avulsion of the lower trunk with middle trunk broken, and 10 root avulsion of the whole brachial plexus. Follow-up of 16 patients showed excellent results in 2 patients, good in 11, fair in 1 and poor in 2. It is suggested that good results can be obtained if multi-paired nerve transfer is adopted in treatment. We conclude that owing to anatomical and physiological characteristics of the respiratory system in children, it is harmful to perform phrenic nerve transfer concomitantly with intercostal nerve transfer. Advisably, two-stage operation is required, otherwise dyspnea and pneumonia are liable to occur. In addition, the time of the operation could be extended to 4-5 years after injury in children, but best results are obtained if the operation is performed within 1 year.
  相似文献   
124.
Ductal adenoma of the breast   总被引:1,自引:0,他引:1  
Ductal adenoma is a recently described benign tumour of the breast that can be mistaken for carcinoma in both frozen and paraffin sections. Such a case is presented. Fortunately a mastectomy was not performed, but the patient did undergo axillary node dissection. Surgeons and pathologists should familiarize themselves with this lesion so that patients do not have to undergo unnecessary mastectomies and axillary node dissections.  相似文献   
125.
The hereditary characteristics of enzyme deficiency and dermatoglyphics in congenital color blindness (CCB) were studied. We propose that there is a linkage between the two loci on the X-chromosome determining CCB and glucose-6-phosphate dehydrogenase (G6PD), based on our study of a high incidence of G6PD deficiency in 156 male cases with CCB. The CCB gene is closely linked with that of G6PD deficiency from our pedigree investigations. The rise in the frequency of eight or more whorls, the low value of atd angle and the presenting rate of real palmar patterns of the thenar, hypothenar and I, areas presented the hereditary traits of congenital color blindness.  相似文献   
126.
本文采用高效液相色谱法测定氨甲环酸中的顺式异构体含量。先用衍生化试剂3,5-二硝基苯酰氯预处理氨甲环酸,然后通过HPLC,以喹啉为内标,YMC-PackAM-302ODS为色谱柱,甲醇-0.02mol/L醋酸铵溶液(4:7)为流动相,在254nm波长处检测,顺式异构体在1~2.5μg/ml范围内线性关系良好(r=0.9961),最低检测限为0.02%。  相似文献   
127.
By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162.  相似文献   
128.
报告应闭合式玻璃体切除术治疗7例(7眼)因视网膜静脉阻塞所致的玻璃体出血。所有病人术后眼底清晰可见,视力明显提高。术后4例出现再出血,经药物治疗后出血吸收,加用氩离子激光视网膜光凝,无再出血。随访3至18个月所有病人无新生血管性青光眼及牵引性视网膜脱离出现。认为玻璃体切除术不但能使屈光间质恢复透明,视力提高,预防牵引性视网膜脱离,而且为明确诊断和进一步激光治疗提供条件。  相似文献   
129.
1. The electrophysiological effects of dicentrine, an aporphine alkaloid isolated from the root of Lindera megaphylla, were examined in the Langendorff perfused rabbit heart and rabbit isolated cardiac cells. 2. Standard electrophysiological characters were measured in the Langendorff perfused rabbit heart (control study) and after 5 min exposure to 1, 3 and 9 microM of dicentrine and during the subsequent recovery phase sequentially (n = 7). The same study protocols were performed in 0.5 to 4.5 microM quinidine (n = 7), 18 to 162 microM procainamide and N-acetylprocainamide (n = 7) for comparison. 3. The results showed that the spontaneously beating heart rate and the sinoatrial (SA) and atrioventricular nodal (AH) conduction time were not significantly affected by dicentrine but were significantly suppressed by the higher doses of quinidine (4.5 microM) and procainamide (162 microM). 4. The His-Purkinje conduction time was significantly increased by the higher dose of dicentrine, quinidine and procainamide. 5. The ventricular repolarization time and its effective refractory period were significantly increased by the higher dose of dicentrine and the other agents. 6. The effective refractory period of the atrium, AV node and His-Purkinje system were also significantly increased by dicentrine and the other agents. 7. A voltage clamp study revealed that the prolongation of atrial action potential duration by dicentrine (9 microM) was associated with a significant inhibition of the transient potassium outward current. As well as inhibition of the transient outward current, a significant inhibition of the sodium inward current by dicentrine was found.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
130.
苯作业工人白细胞降低者的总估校正现患率   总被引:7,自引:0,他引:7  
选择乡镇工业苯作业工人4次外周血白细胞计数中的间隔半年的两次数据,应用俘获再俘获法,计算其白细胞降低者的总估校正现患率(ACPR)。结果苯接触组为36.8l%(29.14%~44.48%),对照组为12.71%(7.20%~18.22%)具有显著差异,其相对危险度为2,9。用常规法求得的4次检出率分别是:苯接触组为26.37%,18.73%,27.93%,36.76%;对照组为6。85%,7.38%,7.94%,15.00%。均在其ACPR之95%可信限内,可见ACPR计算方法简便、结果准确,值得推广。对于稳定的人群,可用其每年一次的健康监护资料计算ACPR。  相似文献   
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