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991.
Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml-1 and 244 to 3,906 pg ml-1, respectively.  相似文献   
992.
993.
994.

Background  

The prebiotic potential of lactulose is well established and preclinical studies demonstrated a protective effect of lactulose in murine models of colitis. The aim of the present study was to investigate the clinical and histological efficacy of lactulose in patients with inflammatory bowel disease (IBD), for which probiotic therapy yielded promising results.  相似文献   
995.
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c…  相似文献   
996.
Previous experiments have revealed sex-dependent effects of inescapable shock in rats. Behavior of male rats was more severely disrupted by inescapable shock than behavior of female rats. These sex differences were found after 1- and 24-hour intervals but not after a 72-hour interval. The present experiment was designed to study various physiological parameters at 1-, 4- and 24-hour intervals after inescapable footshock. The predictability of shock was manipulated by adding a compound light and tone stimulus that preceded shock presentation for one group but was not correlated with shock presentation for another group of subjects. Noradrenaline, dopamine, serotonin, and metabolites of these 3 transmitters were measured in the frontal cortex. Transient shock-induced increments in dopamine and metabolites of dopamine and serotonin were found, but the sex of the animal did not differentially affect this neurotransmitter response. In addition to neurotransmitter concentrations in the frontal cortex, levels of corticosterone were measured in plasma. The pituitary-adrenal axis was activated for a longer period in females than males after shock. The present data do not provide evidence that behavioral sex differences induced by inescapable shock are paralleled by sex differences in neurotransmitter activity. In addition, sex-dependent effects of predictability of shock on neurotransmitter activity were not detected. The relevance of the observed sex-dependent responses in the pituitary-adrenal system is discussed.  相似文献   
997.
OBJECTIVE: Very few studies have examined post-operative morbidity after resection of oesophageal carcinoma, especially in patients treated with induction chemo- and radiotherapy for locally advanced stages. This study assessed the effects of induction chemoradiotherapy on post-operative course after resection of locally advanced oesophageal carcinoma (cT3-4 + cM1lymph). METHODS: Induction therapy consisted of 5-fluorouracil days 1-5 and days 21-25, cisplatin day 1 + day 21 and concomitant radiotherapy 18-20 fractions of 2Gy (total dose 36-40Gy). Induction chemoradiotherapy was completed in 109 patients. Surgery was performed in 90 patients (operability: 90/109 = 83%): 85 patients underwent resection with curative intent (resectability: 85/109 = 78%), bypass operation was performed in five patients. Nineteen patients could not be operated on. Results were compared to a matched group of pT3M1LYM/pT4 patients (n = 86) who underwent primary surgery in the same period. RESULTS: Resection was complete (R0) in 68 patients (68/90 = 76%). Mean duration of surgery was 428 min (range: 240-690). Peroperative complications were haemorrhage in three patients (3/90 = 3.3%), tracheobronchial perforation in three patients (3/90 = 3.3%). Median total hospital stay was 20.5 days (range: 8-355). Mean duration of intubation was 7 days (range: 1-190); 67 patients (67/90 = 74.4%) were intubated for less than 24 h. Non-tumour related hospital mortality after resection was 8.3% (7/84 patients). Mortality after two-field lymphadenectomy was 5.2 versus 11.7% after three-field lymphadenectomy. After primary surgery (n = 86) overall mortality was 2.3% (P = 0.015) and nil after two- and three-field lymphadenectomy (P = 0.011). Medical morbidity consisted of pneumonia in 43 patients (43/90 = 48%), atelectasis in ten patients (10/90 = 11%), dysrhythmia in 21 patients (21/90 = 23%), sepsis in 11 patients (11/90 = 12%) and adult respiratory distress syndrome in ten patients (10/90 = 11%). Surgical morbidity included pleural effusion in 16 patients (16/90 = 18%), tracheal fistula in two patients (2/90 = 2%), chylothorax in two patients (2/90 = 2%) and acute pancreatitis in one patient (1/90 = 1%). Ten patients (10/90 = 11%) had a radiologically confirmed anastomotic leak; however only in four out of them with clinical manifestation; treatment was conservative in all four patients. Major morbidity occurred in 27 patients (27/90 = 30%). Overall rate of morbidity was significantly higher after three-field lymphadenectomy (85%) as compared to two-field lymphadenectomy (68.7%; P = 0.023). CONCLUSIONS: Chemoradiotherapy followed by resection of cT3-4 +/- cM1lymph oesophageal carcinoma is feasible with acceptable mortality. Mortality, however, seems to be significantly higher when compared to a group of pT3M1LYM/pT4 patients who underwent primary surgery (8.3 versus 2.3%; P = 0.015) in the same period in our department.  相似文献   
998.
心脏瓣膜置换术后中远期疗效分析   总被引:8,自引:0,他引:8  
目的 分析探讨心脏瓣膜置换术的中远期疗效。方法  1978年至 2 0 0 1年 12月 ,行瓣膜置换手术 2 14 1例 ,同期随访 16 81例 ,计 80 2 1 1人·年 ,平均 4 77人·年。通过回顾病因、手术方式、瓣膜类型等因素 ,观察术后病人心功能改善情况 ,病死率及并发症等 ,采用t检验 ,多因素回归等统计学方法分析。结果  92例死亡。总体生存率 5年为 (92 3± 2 2 ) % ,10年生存率为 (90 1± 2 7) %。并发症有血栓栓塞、机械瓣膜功能障碍、瓣周漏、溶血、机械瓣膜感染性心内膜炎。术后心功能 (NYHA)与术前比较有明显的提高。结论  1.机械瓣置换术后中远期疗效满意 ,病死率及并发症均较低 ;与术前心功能和手术种类直接相关 ;2 .使用保留瓣下结构及三尖瓣成形术对术后心功能恢复有明显效果 ;3.术中良好心肌保护是提高手术成功率的关键。  相似文献   
999.
We report on a case of esophageal atresia following cervical spine surgery. A swallowing examination was performed using fibre-optic endoscopy and videofluoroscopy. There was scar tissue fixation of the larynx and esophagus to the cervical spine. Operative mobilization of the larynx and esophagus and formation of a sliding layer using a platysma-fascia flap was done. The PEG and tracheal cannula were removed; oral nutrition was initiated after 3 months. Swallowing disorders following operations on the upper cervical spine should be investigated. Careful preparation that preserves the layers should be carried out. Fixation of tissues as a result of scarring should be treated with a sliding layer.  相似文献   
1000.
The bactericidal and sporicidal activities of a peracetic acid disinfectant commonly used in hospitals (Acetoper 200) was studied using three bacterial species recovered in water from hemodialysis machines and humidifiers, i.e., Pseudomonas aeruginosa, Serratia liquefaciens, and Bacillus subtilis (spores). The method used was derived from AFNOR norms NF T 72-151 and NF T 72-231. For each strain, three concentrations of disinfectant were tested. Counts were performed every five minutes for one hour to evaluate killing kinetics. For both Gram-negative organisms, survival curves were biphasic, whereas B. subtilis counts decreased logarithmically. Both concentration and time influenced the 5 log10 decrease in counts. With S. liquefaciens and B. subtilis (spores), the 5 log10 decrease was not reached with low levels of disinfectant. In every case, the D value decreased substantially with increasing levels of disinfectant.  相似文献   
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